Textiles and Environment 938030899X, 9789380308999

Table of contents :
Content: Preface. Role of chemical management services in industries. Eco-processing of textiles. Ecological dyeing process. New concepts in eco-friendly processing. Environmental impact solutions. The world of eco-fibres and other textiles. Herbal dyeing process. Carbon footprint in textile industry. New technologies and in textile dyeing and finishing. Dyeing technologies for the future. Importance of blue sign in textile industry. Processing of recycled polyester fiber in textile industries. Waterless dyeing process. Role of green technologies in industries. Salt-free reactive dyeing of cotton. Electro-coagulation process for the waste water treatment. AirDye technology. World of recycled fibres. Application of green chemistry in industries. Life Cycle Assessment (LCA) of textiles. What is ZDHC (Zero Discharge Hazardous Chemicals)? What is Higg Index? All about Mark and Spencer Plan A. Greenpeace and its toxic campaigns. Restricted substances lists (RSLs). Sustainable fibres. Importance of Compliances for brands and retailers. The importance of SIN (Substitute It Now!) List. Index.

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Textiles and environment

Textiles and environment

Dr. N N Mahapatra

WOODHEAD PUBLISHING INDIA PVT LTD New Delhi

Published by Woodhead Publishing India Pvt. Ltd. Woodhead Publishing India Pvt. Ltd., 303, Vardaan House, 7/28, Ansari Road, Daryaganj, New Delhi - 110002, India www.woodheadpublishingindia.com

First published 2015, Woodhead Publishing India Pvt. Ltd. © Woodhead Publishing India Pvt. Ltd., 2015 This book contains information obtained from authentic and highly regarded sources. Reprinted material is quoted with permission. Reasonable efforts have been made to publish reliable data and information, but the authors and the publishers cannot assume responsibility for the validity of all materials. Neither the authors nor the publishers, nor anyone else associated with this publication, shall be liable for any loss, damage or liability directly or indirectly caused or alleged to be caused by this book. Neither this book nor any part may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, microfilming and recording, or by any information storage or retrieval system, without permission in writing from Woodhead Publishing India Pvt. Ltd. The consent of Woodhead Publishing India Pvt. Ltd. does not extend to copying for general distribution, for promotion, for creating new works, or for resale. Specific permission must be obtained in writing from Woodhead Publishing India Pvt. Ltd. for such copying. Trademark notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation, without intent to infringe. Woodhead Publishing India Pvt. Ltd. ISBN: 978-93-80308-56-2 Woodhead Publishing India Pvt. Ltd. e-ISBN: 978-93-80308-99-9

Contents

Preface

xv

1. Role of chemical management services in industries

1



1 6

1.1 1.2

Introduction to chemical management Chemical management services (CMS)

2. Eco-processing of textiles

7

2.1 Eco-processing 2.2 Eco-bleaching 2.3 Eco-dyeing 2.4 Eco-finishing 2.5 Eco-printing

7 9 10 11 12

3. Ecological dyeing process

13

3.1 Introduction 3.2 CO2 dyeing 3.3 Polyester CO2 dyeing machine 3.4 CO2 dyes

13 15 15 16

4. New concepts in eco-friendly processing

20

4.1 Introduction 4.2 Researches for organic processing 4.3 Introduction to eco-friendly processes

20 21 22



23 27

4.4 4.5

Serving resources in textiles Dow Corning and denim processing

vi

Textiles and environment

5. Environmental impact solutions

29



29 30 31

5.1 5.2 5.3

Introduction Protect your data and your planet A commitment to the environment

6. The world of eco-fibres

33

6.1 Introduction 6.2 Characteristics of eco-fibres 6.3 Classification of eco-fibres 6.4 Natural origin eco-fibre 6.5 Hemp bio-commodities 6.6 Regenerated fibres 6.7 Recycled synthetic fibres 6.8 Recycled polyester 6.9 Recycled nylon 6.10 Fibres from waste products 6.11 Blends 6.12 Drawbacks of using eco-fibre products 6.13 Verification 6.14 Comparison of fibres

33 33 34 34 36 38 39 39 39 40 40 40 41 41

7. Hazardous substances in clothing and other textiles

42

7.1 Introduction 7.2 Alkylphenols 7.3 Phthalates 7.4 Brominated and chlorinated flame retardants 7.5 Azo dyes 7.6 Organotin compounds 7.7 Perfluorinated chemicals 7.8 Chlorobenzenes

42 46 46 46 47 47 47 48

Contents vii



7.9 Chlorinated solvents 7.10 Chlorophenols 7.11 Short-chain chlorinated paraffins 7.12 Heavy metals: cadmium, lead, mercury and chromium (VI)

48 48 48 49

8. Herbal dyeing process

50

8.1 Introduction 8.2 Facts of chemical processing 8.3 Desizing 8.4 Bleaching 8.5 Mordanting 8.6 Dyeing 8.7 Finishing 8.8 Recycling plant 8.9 Major differences between various dyes 8.10 Major herbal dyes available

50 52 52 52 53 53 53 53 54 55

9. Carbon footprint in textile industry

57

9.1 Introduction 9.2 Greenhouse gases and global warming 9.3 Global warming and the textile industry 9.4 Primary and secondary footprint 9.5 Carbon footprint and the textile industry 9.6 Strategies for reducing carbon footprint 9.7 Revolutionary dyeing technologies 9.8 Indian textile industry oblivious

57 57 58 58 59 60 61 61

10. New technologies and in textile dyeing and finishing

65

10.1 Introduction 10.2 Requirements

65 66

viii



Textiles and environment

10.3 10.4 10.5 10.6

Electrochemical process technology Supercritical fluid dyeing technology Plasma treatment technology AirDye technology

66 67 68 69

11. Dyeing technologies for the future

71

11.1 Introduction 11.2 Options to overcome the environmental problems in the future 11.3 AirDye technology 11.4 Conclusion

71 72

12. Importance of blue sign in textile industry

80



80 80 81 83 84 85 86 87

12.1 Introduction 12.2 Blue is for clean 12.3 First products in the marketplace 12.4 The principles of bluesign 12.5 Three steps to achieving bluesign standard 12.6 What’s blue and what’s black 12.7 Ecology and high-tech go hand-in-hand 12.8 Science – A better tailor than nature

75 78

13. Processing of recycled polyester fiber in textile industries

88



88 89 89 91

13.1 Introduction 13.2 Manufacturing process 13.3 Properties of recycled polyester fiber 13.4 Uses

14. Waterless dyeing process

92

14.1 Introduction

92

Contents ix



Supercritical fluid CO2 / supercritical fluid dyeing technology 14.3 Dyeing polyester and other synthetics 14.4 Reductions in operating costs 14.5 Availability

94 94 95

15. Role of green technologies in industries

96



14.2

15.1 Introduction 15.2 Goals of green technology 15.3 Types of green technology 15.4 The future of chemistry

92

96 97 97 100

16. Salt-free reactive dyeing of cotton

101

16.1 Introduction 16.2 Modification of cotton fiber

101 101

17. Electro-coagulation process for the waste water treatment

106

17.1 Introduction 17.2 What is chemical coagulation? 17.3 What is electro-coagulation?

106 106 106



17.4

107



17.5



17.6

ETP operating for 1000 m3 per day (electro-coagulation plant) ETP operating for 1000 m3 per day (physical chemical plant) Comparison of chemical coagulation and electro-coagulation

108 108

18. AirDye technology

110

18.1 Introduction 18.2 How is AirDye different? 18.3 Take a very close look

110 111 111

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Textiles and environment

18.4 Advantages of AirDye technology 18.5 Conclusion

113 114

19. World of recycled fibres

115



115 116 116 117 118 118 119 119

19.1 19.2 19.3 19.4 19.5 19.6 19.7 19.8

Recycling processes Special processes Recycling facts Benefits of textile and clothing recycling Recycled polyester Recycled nylon/polyamide Recycled cotton Recycled wool

20. Application of green chemistry in industries

125



Introduction to green chemistry Developments in green chemistry Applications of green chemistry

125 125 127

21. Life Cycle Assessment (LCA) of textiles

129



129 130 132 133



20.1 20.2 20.3

21.1 Introduction 21.2 LCA calculator 21.3 Life Cycle Assessment of cotton fibre 21.4 LCA: A decision-making tool for recycling processes in textile industry 21.5 Life cycle of a T-shirt 21.6 The life cycle of making a T-shirt

134 134

22. What is ZDHC (Zero Discharge Hazardous Chemicals)?

136



136 136

22.1 22.2

Introduction Main successes of ZDHC Group

Contents xi



22.3 22.4 22.5 22.6

Main challenges to the ZDHC Group Working with Greenpeace The Joint Roadmap Benefits to participation

137 138 139 140



22.7

141



22.8 22.9 22.10 22.11 22.12 22.13

Governance policies and procedures of the zero discharge programme Greenpeace slams latest ZDHC Roadmap ZDHC identifies key transparency tool ZDHC Group reports latest progress H&M commitment towards ZDHC Actions taken so far PUMA Roadmap towards zero discharge of hazardous chemicals

142 142 142 142 143 143

23. What is Higg Index?

145



23.1 Introduction 23.2 Vision 23.3 Mission 23.4 Current focus

145 146 147 147



23.5 Where we are: the Higg Index 1.0 23.6 A new yardstick 23.7 Scope 23.8 The Higg Index 23.9 Higg Scoring 23.10 Who’s on Board? 23.11 Where we’re headed? 23.12 How does the Higg Index work?

147 147 149 149 150 150 150 151

24. All about Mark and Spencer Plan A

153



153

24.1

Introduction

xii

Textiles and environment



24.2



24.3

Giving back: a charity partnership between M&S and Oxfam Next phase of Plan A

156 158

25. Greenpeace and its toxic campaigns

159

25.1 Introduction 25.2 Detox campaign 25.3 LV, Versace, Dolce&Gabbana fail in Greenpeace’s toxic chemicals test 25.4 Gap pledges to eliminate toxic chemicals, but Greenpeace isn’t happy 25.5 Heros or zeros? 25.6 Different strokes 25.7 H&M pledges to eliminate toxic chemicals from supply chain by 2020 25.8 Detoxing H&M 25.9 Greenpeace targets Zara in global Detox campaign

159 161 161

26. Restricted substances lists (RSLs)

168



168 170 173 173 174 174 175 175

26.1 Introduction 26.2 Methodology 26.3 Amines 26.4 APEO and NPEO 26.5 Benzotriazole (MBT) 26.6 Chloro-organic carriers 26.7 Chrome VI 26.8 Flame retardants

162 163 163 164 164 165

27. Sustainable fibres

176

27.1 Cotton

176

Contents xiii



27.2 HEMP 27.3 Bamboo 27.4 Soya 27.5 Eucalyptus Tencel

27.6 Recycled PET 27.7 Wool

177 177 178 178 178 179

28. Importance of Compliances for brands and retailers 181

28.1 28.2

Toxic avengers Greenpeace study

181 183

29. The importance of SIN (Substitute It Now!) List

185



185 185 188

29.1 29.2 29.3

Introduction Substitute It Now! What is the SIN List vs. the SVHC List?

Index

190

Preface

The book is written based on my 30-year experience of working in various textile mills in India and abroad. This book includes my knowledge and experience on modern topics which I have highlighted in many textile conferences in India and abroad. This book would be very helpful to textile students, textile scientists, textile research scholars, and textile designers who are the thinkers and future of the Indian textile industry. In this book, I have also attended various burning problems in the textile industry. I have emphasized on the different environmental requirements being followed in the textile manufacturing units. Nowadays all big retailers and buyers are prescribing new environmental compliances. I have discussed on how to handle all these norms. I am proud to say that I have taken special training in Hong Kong and China regarding all new certificates and ecological considerations. I am thankful to Mr Dilip Gianchandani, former director of Intertek India Pvt Ltd for giving me the scope to visit these two countries and know more about the certifications. I would like to convey my sincere gratitude to Mr Subhash Bhargava, MD, COLORANT LTD, Ahmedabad for giving me permission to attend national and international conferences and deliver talks on environmental issues. I would also like to put my special thanks to Mr S.N. Goyal, President, BMD LTD (LNJ BHILWARA GROUP), Banswara, Rajasthan for sending me to take further training on Ecological Standards at Melba Industries, Melbourne, Australia. I am also grateful to my wife Seemani and Daughters Nittisha and Sanchitta for giving me moral support to fulfill my dream. Last

xvi

Textiles and environment

but not the least my sincere thanks to Mr Krishnan, Editor, Dyechem Pharma, Mumbai and Mr. Dilip Raghava, Editor, Colourage, Mumbai for giving me permission to include in this book few of my already published articles in journals. I want to dedicate this book to my Late father Prof Dr Gokulananda Mahapatra (Retd Prof of Chemistry and well-known Popular Science writer) and my Late mother Mrs Kumudini Mahapatra. Dr N N Mahapatra

1 Role of chemical management services in industries

1.1

Introduction to chemical management

It is a business model where a customer engages with a service provider in a strategic, long-term contract to supply and manage the customer’s chemicals and related services. Both have to work together to streamline and automate their chemical sourcing and management. The CMS programs include elements from sourcing materials, electronic MSDS management, and point-of-use replenishment to hazardous waste management and tracking. The model provides customers access to an automated, online materials catalogue for quick and easy ordering. Additional services, such as point-ofuse replenishment, can also be established to further streamline the process and improve environmental tracking and reporting of chemicals. Aggregating demand, purchasing and inventory with suppliers under such programs will reduce cost in material spend and significantly decrease material management expenses. Following services can be utilized in a customized chemical management services offering: • Hazardous material gate keeping – Develop and maintain an Approved Products List (APL), which documents materials authorized for the site and provides a web-based electronic chemical authorization request form that can be automatically routed to the proper approvers. • Forecasting – Accurately predicting future customer requirements/ demand patterns based on historical demand, real-time consumption rate information and production schedules. • Procurement/purchasing – All actions related to acquisition planning, solicitation, evaluation, negotiations, contract award, contract administration, and contract management functions. • Monitor compliance with original material requisition and purchase order, certificate of analysis or conformance review, labelling, special testing or source inspection requirements, and ongoing shelf-life and storage tracking. • Inventory management/storage/warehousing – All warehouses must be regulated material-storage compliant and managed by trained

2

Textiles and environment

personnel equipped to handle HAZMAT. Warehouses should provide climate controlled storage for time-and-temperature sensitive (TATS) materials. • Delivery to dock – Items should be picked and packaged according to requirements for DOT (if shipping via ground) and IATA (if shipping via air). Materials must be labelled with usage area and building cabinet location. All packaging and shipping tasks must be performed by trained and certified personnel only. • Delivery to point of use (POU) – Avchem unpacks materials from delivery vehicle, stages the material, and removes all dunnage, packing material, and excess pallets from property. Material is delivered directly to the POU, existing product is rotated to promote FIFO usage prior to expiration and expiring product is removed from POU. • Environmental, safety, and occupational health (ESOH) services – These services provide an effective, sound environmental, safety and occupational health management system. Avchem tracks and provides reporting down to the CAS-constituent level to satisfy Federal, state and local storage/consumption reporting requirements. • Waste management – Set up, collect and maintain satellites manage 90-day storage location, coordinate manifest and transport to TSDF, and provide waste generation and reporting tools. Pursue waste reduction opportunities and recycling. The RIGHT Material, at the RIGHT Place, at the RIGHT Time, in the RIGHT Way, at the RIGHT Cost. “Chemical Management Services create savings and process improvement”. Chemical Management Services program (CMS) is a unique approach to the chemical management services concept that more and more manufacturing companies are leveraging for a better bottom line. We see chemical management services as a comprehensive way to deliver value to our customers. We use our extensive industry knowledge and process expertise to understand your specific issues, solve your particular problems, and implement demonstrated solutions. As a result, you experience improvements in productivity, quality, and profitability, immediately and into the future. Adding value to your company • Chemical procurement for reduced costs • Environmental tracking and reporting for improved compliance • Process monitoring for increased production • Leveraged best practices for increased profitability



Role of chemical management services in industries

3

The four different levels of integration: 1. Starting with chemical procurement – This assumes responsibility for the entire inventory of process chemicals. That means one will get rid of placing orders and will be ensured of delivery and control of inventory; thus saving lot of time and money. This will help you in getting rid from the basic efficiency of CMS, as the lowest costs for chemical supply are ensured – regardless of the source. 2. Health, safety and environmental tracking and compliance – With its commitment to environmental protection and health and safety standards, one can be assured of compliance and industry leading product stewardship, based on ChemTRAQ™ software. ChemTRAQ™ is a comprehensive database developed to meet regulatory standards. This will ensure quick and efficient MSDS and environmental reporting always. 3. Turning knowledge into value with process monitoring – The onsite team at your plant will be committed to working with your plant management organization to optimize your production processes. The team will use its product knowledge and analytical capabilities to leverage the knowledge and experience of your plant staff to resolve problems and optimize processes quickly and efficiently. 4. Leveraging improvements – At this level, CMS becomes a true partnership, with services such as benchmarking of best practices and associated costs per unit, as well as R&D for process improvement – and guaranteed results. In this new model, manufacturers shift away from a traditional supplier relationship to a strategic alliance with a chemical service provider. Results to date indicate that this service model has proven to achieve resource efficiency, process innovation, and significant cost savings. The on-site team serves as your eyes and ears, capturing data and analyzing the results to provide you with reports and recommendations on how to reduce costs and improve performance. • Chemical management services – or CMS – This is an evolving business segment of the chemical supply business. In essence, CMS is providing a cradle-to-grave management of chemical inputs to (generally) a nonchemical company so that the following benefits are provided: – Minimum volumes of chemicals are used – Minimum waste is produced – Waste produced is dealt with effectively – Regulatory actions are fulfilled and regulatory entities are satisfied

4

Textiles and environment

– Technical know-how is provided – Inventory is minimized – Paperwork is minimized or dealt with by the supplier as much as possible – Chemical flows and financial results are regularly monitored and reported to the customer And the overall effect of these services is: – Bottom-line chemical costs are lowered. –  The risks of dealing with chemical materials, especially hazardous chemicals, are minimized. – The supply of critical materials – or moreover, the function the material provides – is assured. Virtually every supplier of chemicals would claim to provide these services and benefits. And in reality, most do supply some or many of these services. This is what competition is often based on, especially in the specialty chemical businesses. The avenues by which products get to market have always been several. The differentiation of these ways is many, but useful criteria include the level of involvement of the supplier of goods with the user of these goods. Effective use of different types of products – or in this case, chemicals – requires different levels of interaction between suppliers and users. There is a spectrum of interaction intensity levels in the chemical industry and one’s placement in this spectrum depends on the sophistication of the supplier, the user and the complexity of use of the product. It is that last point – the product and all the issues surrounding it – that has been a major factor in the rise of a new group of companies that are increasing their share of chemical sales – and service – at a high rate. Many factors are contributing to increasing sales for CMS providers. Perhaps chief among them is the increasing complexity of regulations concerning the use of chemicals and especially regulations concerning the disposal of used chemicals and any by-products that might arise from their use. While chemical companies as a necessary requirement of doing business must deal with these regulations and the paperwork/documentation that is ultimately required, companies that consume small amounts of chemicals find these regulations especially burdensome. The chemical materials are essential to their business but require time and effort to meet legal requirements sometimes out of proportion to the volume of use. CMS companies can provide substantial alleviation of these burdens. Avoidance of such burden is hardly the only motivator. Small volumes of chemicals can have a profound impact on the quality of the products that the using companies are manufacturing (or even the services they are providing).



Role of chemical management services in industries

5

But broad knowledge – and the research and development necessary to expand that knowledge – is simply not available to these users through their own resources. Some CMS providers focus on a limited number of applications and markets, but provide a wide range of products – and customer service offerings – within these markets. Users can benefit from these endeavours and leverage that knowledge into product performance, low cost and other benefits. Similarly, the CMS provider can bring the expansive expertise of their suppliers as well (except where competition limits such exchanges). Bottom line cost is also a major factor. Indeed, if this were not so, this business model would not likely exist, and manufacturers and distributors would fill most supply requirements adequately. All suppliers strive to provide the best “bottom-line” cost solution to a customer’s supply needs. Indeed, this is what most suppliers of specialty – especially functional specialty – chemicals try to do. But CMS suppliers often extend this to a broader range of products in an industry or application focus and are organized to do so when the customer requires relatively small volumes of chemical products. The following chart illustrates how the CMS company provides various services throughout the use cycle in the purchasing company. It is important to note that the level of these services will vary among the various types of suppliers of chemicals, including CMS companies as well. In general the level of supply of these services will increase from the commodity supplier to the specialty provider. The major differentiator of CMS companies from other chemical suppliers is the intensity of the service, especially during the end-ofuse phase, which is recycling or waste disposal. Aspects of CMS Few provide all

Pre-Use – Supply – Suggest potential alternatives – Warehousing

Use

Post-Use

– Waste disposal – Monitoring use and its transportation – Inventory control – Regulatory issues – EHS issues • Compliance • Compliance • Verification • Paper work – Training – Systematic – Recycling communication – Maintenance – Waste issues • Cost minimization • IT programs – IT systems development

6

Textiles and environment

It should be noted that the CMS market is not limited to suppliers of chemicals. A number of significant players in the market do not supply chemicals. While these companies are of secondary interest to this report, they nonetheless play a significant role in CMS. Included in this category of suppliers are most notably software suppliers. The role of these companies can be several. They can allow for some companies to essentially be a provider of their own CMS through use of techniques and products that are developed by this set of suppliers. Another major factor that differentiates CMS companies from other types of chemical suppliers is the nature of the customers. A majority of chemical sales is to other chemical companies. If the value of interplant transfers is taken into account, this number rises to a very high percentage. And if the sales of polymers to polymer processors are included, then the amount of chemicals and related materials sold to chemical companies is likely well in excess of 90%. This new Safe & Sustainable Chemicals report discusses the dynamics of this evolving market, provides a discussion of regulatory factors impacting the chemical industry, and analyzes current and potential markets for CMS. A list of current CMS providers as well as chemical distributors is included. Brief profiles of seventeen major CMS companies are also provided.

1.2

Chemical management services (CMS)

Integrated chemical services, also called total chemical management or CMS, include the development of chemicals according to customer requirements, the provision of logistics solutions, administration, process development, chemical application, and waste management. The majority of chemical management services in Europe are large international chemical companies such as Dow, Castrol, Quaker, PPG, and BASF that were able to broaden their market share or become the sole providers of CMS by extending the range of their chemicals and adding information management and technical services to their chemicals business.CMS customers in Europe and America are primarily large, multinational Fortune 500 companies in the automotive, metalworking, aerospace, and electronics sectors. Automotive companies such as Volkswagen, Daimler Chrysler, Volvo, Ford, Toyota, and General Motors have been outsourcing the management of their paint shops in Europe, and some of these facilities are now also moving toward total outsourcing of chemical management. Prominent companies in the semiconductor industry, such as STMicroelectronics, Micron Technologies, and Motorola, have also been using chemical management services for many years. New areas of CMS growth in Europe include the pulp and paper industry and the life sciences industry.

2 Eco-processing of textiles

2.1 Eco-processing Eco-friendly processing is also called as eco-processing. Eco-processing is a suitable textile processing method that delivers not only eco-friendly finished products but also does not hamper the surrounding atmosphere and environment by way of polluting the air and water respectively, due to emissions and effluent water discharges. We are already fully aware of the implications of the damages already done to water and environmental resources by gas and effluent discharges from polluting industries such as textile and leather processing. Textile Industries use different chemicals in different processes like, dyeing, finishing, scouring, bleaching, softening, washing, etc. The textile chemicals & dyeing industry consume large quantities of water and produce large volumes of wastewater in different processes. Wastewater from textile processing and dyeing containing residues requires appropriate treatment before being released into the environment. The increasing awareness of environmental issues has led to interest in eco-friendly processing of textiles. In this global competition, ‘quality’ and ‘ecofriendliness of process and product’ play a key role. To save the environment by reducing pollution from various industries, automotives etc., several world organizations have been established and many stipulated norms and standards have been formulated. Throughout the world, almost all countries have set up certain rules and regulations for importing and exporting processed textile goods. Similarly, there are many certifying organizations that test and certify the finished goods to match the importing standards. The certification by these organizations either for the product or for process is called eco-labelling. Few of eco-limits and eco-parameters are listed below: • Prohibited amines in azo dyes • Chlorinated phenols • Formaldehyde • Extractable heavy metals • Residual pesticides • Allergic dyes

8

Textiles and environment

• Chlorinated benzene and toluene compounds • Phthalates • Organo tin compounds The presence of above-mentioned chemicals beyond certain prescribed limits is banned in textiles meant for civilian use. With reference to these banned chemicals, certain parameters have been fixed by various stipulating bodies. Eco-label products are being produced adhering to the above parameters. There are many organizations in different parts of the world which specify certain criteria for importing textile goods from other exporting countries. The following organizations are some of important ones in this list. Government organizations

Commercial organizations

Eco Mark – Japan

Okeo Tex 100, Germany, Austria

Green Seal – USA

Tox Proof _TUV, Germany

Flower – EV

GuT, Carpets, Germany

EKO-Seal (Holland)

Steilmann

Environmental Choice (Canada)

Otto Versand

Green Mark (China, Taiwan)

Hess Natur

Eco-Mark (India)

Green Cotton

The following regulatory laws prevail in Germany concerning ecology of textiles. • Food & Consumer Products law – Allergic disperse dyes and chromium IV • Consumer Products Ordinance – Flame retardants, azo dyes, nickel and formaldehyde • Chemical Prohibition Ordinance – DDT, dioxins and furons, mercury, PCB, PCT, PCP, flame retardants and azo dyestuffs. There are two types of criteria for eco-labelling: • Product based: This pertains to the limits of harmful chemicals used in various textile processes. – Group I includes clothes and textiles for babies below age 3. The limits (stringent) are the lowest for this category. – Group II includes materials that come in direct skin contact or worn next to skin; for e.g. underwear, bed sheets and night dresses. – Group III includes materials that do not come in direct skin contact; for e.g., textiles worn as second layer dresses, coats, articles with linings.



Eco-processing of textiles

9

– Group IV includes furnishing articles and accessories for decorative purposes; for e.g., table wear, upholstery, curtains, textile flooring and mattresses. • Process based: This includes recommendations for textile processes to be avoided such as: – Bleaching with hypochlorites – Use of chlorinated organic compounds as carriers in polyester dyeing – Optimum use of water and energy Dyestuffs when exhausted on fibre are fixed only to the extent of 50– 90%; the unfixed exhausted dye along with additive chemical impurities contaminates the effluent; hence, there is a need to ensure that the dyestuff and dye additives that are used in the dyeing process are eco-friendly. Ecological norms for the dye are considered assuming its concentration up to 10% in textiles and 2% dye diluted to 1:2500 in effluent. Fastness properties of dyes on finished textiles also form part of econorms considering their possible transfer on the skin. Some of the eco-friendly suggestions for textile processing are: • Reduce water and energy consumption during preparation, coloration and finishing • Reduce aqueous waste and off-gases • Improve process efficiency • Reduce exposure to hazardous chemicals Serving resources in textiles: Some dyes and chemical manufacturers like Huntsman delivers a range of innovative effects, which: • reduce the amount of energy required in the care of garments • keep clothes fresher without washing • keep garments looking new for longer • reduce or eliminate the need to tumble dry or iron • eliminate the need to dry clean

2.2 Eco-bleaching The bleaching process that is most suitable and within the norms of eco-label standards is called eco-bleaching. Some of the useful tips one may consider are: 1. Use only APEO and NPEO free wetting and scouring agents. 2. Do not use ethoxylate-based surfactants. 3. Do not use phosphate-containing surfactants.

10

Textiles and environment

4. Instruct your sizing department to avoid using PCP, TCP and Copper Sulphate or Nickel salts as preservative for their size material. 5. Do bio-scouring. 6. Do not go for hypochlorite bleaching. Do only hydrogen peroxide bleaching. 7. Do consult your enzyme suppliers for a suitable process for enzyme scouring/bleaching and adopt the process at least for RFD quality fabric/yarn. 8. Do not let out the processed liquor go directly to ground. Emphasize on zero discharge system of effluent treatment.

2.3 Eco-dyeing The dyeing process that is most suitable and within the norms of eco-label standards is called eco-dyeing. Some of the useful tips you may consider are: 1. Select dyestuff that does not contain chlorinated benzene and toluene. 2. Avoid using carcinogenic dyestuffs in combinations. 3. Avoid using allergic dyestuffs (some selected disperse dyes are allergic). 4. Do not use chelating agents that contain phosphates. 5. Use APEO and NPEO free surfactants as dispersing agents. 6. Ascertain that your surfactant does not contain any ethoxylated products. 7. Use formic acid for neutralization purposes rather than acetic acid. 8. Do not use formaldehyde containing dye fixing agents after reactive/ direct dyeing. 9. Prefer natural dyes or dyes that do not have heavy metals, etc. 10. Most important is to control and limit the use of water for all purposes. 11. If reactive dyeing is carried out, where ever possible go for low salt and no salt dyeing/trials. 12. Avoid reprocessing, save energy, money and water. 13. Try and establish a system of Right First Time practice in dyeing. 14. In reactive dyeing, where ever possible you may try cold dyeing to save energy. Preconditioning method is one such procedure. 15. In disperse dyeing, avoid using phenolic carriers. Select dyestuffs carefully. 16. In wool and silk dyeing, metal complex dyes’ selection should be optimistic. 17. In all cases of wet processing, establish a suitable system of water recycling either with an R.O. system or Nano system.



2.4

Eco-processing of textiles

11

Eco-finishing

Finishing process that is most suitable and within the norms of eco-label standards is called eco-finishing. Some of the useful tips you may consider are: 1. Do not use formaldehyde-based crease resist/anti-shrinking/ wrinklefree finish substances. 2. If you are using any binder type of resins for stiff finish, check for free formaldehyde. 3. Have the practice of stocking the finish liquor used in stenter padding mangles. 4. Please go into the details of chemicals in every finishing agent, such as anti-pilling agent, anti-microbial agents, etc. The presence of PCP, PCB and TCP should be checked and avoided. 5. Avoid using acetic acid in finishing recipes and better use formic acids where ever possible. 6. Vapors and fumes of Ammonia, Formaldehyde, Benzaldehyde, etc., are injurious to health. Some unique products of interest may be: 1. Cationic softener: Treated goods retain their wetting properties while their softness, hydrophilicity, breathability and anti-static properties are greatly enhanced. Most products are made from plant extracts; do not use which consists of animal extracts. 2. Antiozone softener: Effective cationic anti-ozone softness to treat premature yellowing of indigo denim garments. This imparts protective colloids over indigo dyes and softness to fibres. 3. Weak anionic softener: Made from advanced absorbent cosmetic raw materials. Treated goods will yield hydrophilic, fluffy, non-yellowing, high water absorbency, high wicking and extremely good lubricating effects. Ideal to be used for hosiery, 100% cotton knits, especially on white fabrics. 4. Non-ionic polymer softener: Prill-type concentrated softener which yields lubricating type, bulky soft hand feel with anti-static properties. Imparts anti-static, strong hydrophilicity and superior anti-tear, anti wear strength to treated fabrics. 5. Silicone softener: Micro to nano size amino reactive silicone softeners. Applicable from low to high temperatures, yields slick and soft hand feel to treated fabrics at economical costs. 6. Softonic Conc: Alkaline pH (up to pH 9.5), high temperature (up to 95°C) resistant, spot-free silicone emulsions with high active contents. Yields hydrophilic soft hand feel. Non-yellowing.

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2.5 Eco-printing The printing process that is most suitable and within the norms of eco-label standards is called eco-printing. Some of the useful tips you may consider are: 1. Water-based inks do not contain PVC or phthalates and you don’t need solvents to clean the screens down after they’ve been used – you can clean them with water. 2. They do not contain ozone-depleting chemicals such as CFCs and HCFCs, aromatic hydrocarbons or any volatile solvents. 3. They do not contain lead or any heavy metals. In fact, do not contain any toxic chemicals at all! Not even white spirits like other waterbased inks in the market. 4. It passed the Oekotex Class 1 standard (with 60% to spare!) and is safe to use on underwear, swimwear and even baby clothes. 5. Water-based inks can be difficult to use. They are air dry and can clog up the screen during printing. It takes a bit of getting used to but it’s worth it. 6. Traditionally, water-based inks were not as hardwearing and durable as plastisol inks and weren’t as opaque but things are different now. 7. It is highly durable to wash, wear and even to dry clean. Washing recommended up to 40°C but don’t recommend tumble drying. 8. The inks contain a superior pigment colour for brightness and opacity, which means that you can use water-based inks on dark colours without having to resort to bleaching the fabric using harmful discharge printing. 9. Water-based inks have the added benefit that they don’t have a rubbery feel like plastisol inks or transfer printing and are softer to the touch.

3 Ecological dyeing process

3.1 Introduction Most of the discussion in sustainable textiles has centred on the fibres – manufacturers switching to organic cotton, or creating fabrics from renewable materials like bamboo or hemp. But very little attention has been paid to the dyeing process, which can be a potentially devastating industry when it comes to chemicals, waste and water usage. AirDye, a new method created by Colorep for dyeing textiles, takes water almost out of the equation, using not only 90% less water but also reducing the emissions and energy use by 85%, since extreme heat is needed to dry the textiles after they are soaked in dye (and most fabrics then require a postrinse and yet another dry cycle). AirDye’s process begins with using all synthetic fibers for its material, which can be made from recycled PET bottles. Using dispersed dyes that are applied to a paper carrier, AirDye uses heat to transfer the dyes from the paper to the surface of the textiles, coloring it at the molecular level. All paper used is recycled, and dyes are inert, meaning that they can go back to their original state and be reused. The textile industry is believed to be one of the biggest consumers of water. In conventional textile dyeing, large quantity of water is used both in terms of intake of fresh water and disposal of waste water. On average an estimated 100–150 litres of water is needed to process 1 kg of textile material. Water is used as a solvent in many pre-treatment and finishing processes, such as washing, scouring, bleaching and dyeing. Water scarcity and increased environmental awareness are world-wide concerns causing a sharp rise in prices for intake and disposal of water. New legislation will even endanger the continuity of textile dyeing companies in the near future. Elimination of water process and chemicals are a real breakthrough for the textile dyeing industry. DyeCoo Textile Systems designs and manufactures machines using carbon dioxide (CO2) for dyeing of textile materials. It’s a complete waterfree dyeing process with considerable lower operational costs compared to the conventional dyeing processes.

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Advantages: • Elimination of water consumption • Elimination of wastewater discharges • Wastewater treatment process eliminated • Elimination of drying and dryer effluent • Reduction in energy consumption • Reduction in air emissions • Reduction in dyeing time • Surfactants and auxiliary chemicals in dyes eliminated • Dye utilization is very high with very little residue dye Unused dye can be recaptured • Approximately 95% of used CO2 will be recycled • Fewer redyes are required • Color correction is easier compared to aqueous dyeing. Quality, economic efficiency and, more and more, ecological methods are the prerequisites for up-to-date production in the dye house. Color shade and depth must be attainable, and there should be adequate levelness and accurate fastness properties. Appropriate mechanical and chemical processing is necessary to suit customer requirements as well as to create the required fabric with hand-and-surface characteristics. Economical and ecological efficiency involves minimization of costs and maximum profitability as well as reproducible quality with minimal environmental damage. Therefore, process optimization is a must to fulfil all parameters and requirements for right-first-time production. Western wet-finishing costs are more and more apparent in various Asian countries as well and can be divided into the following approximate cost proportions: • 42% labor • 29% dyestuffs and chemicals • 6% water • 12% energy • 6% environment and safety measures • 5% maintenance Requirements The catalogue of modern, up-to-date dyestuffs and dyeing and finishing equipments offers a blend of modern technology and chemistry. Major requirements are as follows: • Reduced water consumption • Varying load capacity • Time savings • Comparable economy and ecology • Highly optimized rinsing processes





Ecological dyeing process

• • • • •

15

Controller units Downstream processing advantages Wet finishing process Economical finishing Monitoring and controlling

3.2 CO2 dyeing When carbon dioxide is heated to above 31°C and pressurized to above 74 bar, it becomes supercritical, a state of matter that can be seen as an expanded liquid or a heavily compressed gas. Characteristic of a supercritical fluid is a high (liquid-like) density that enables dissolution of compounds. For dyeing in supercritical carbon dioxide, the CO2 is heated to 120°C and pressurized to 250 bar. The CO2 penetrates synthetic fibres, thereby acting as a swelling agent during dyeing, i.e. enhancing the diffusion of dyes into the fibres. In other words, the glass transition temperature of the fibres is lowered by the penetration of the CO2 molecules into the polymer. This accelerates the process for polyester by a factor 2. Finally, the CO2 is able to transport the necessary heat from a heat exchanger to the fibres. During the dyeing of polymer fibers, CO2 loaded with dyestuff penetrates deep into the pore and capillary structure of fibers. This deep penetration provides effective coloration of these materials which are intrinsically hydrophobic. The process of scouring, dyeing, rinsing, drying and removing the excess dye can be carried out in the same batch.

3.3

Polyester CO2 dyeing machine

Specification DyeOX 2250 series 1 (3 dyeing vessels) Working temperature −10 / 120OC Design temperature −10 / 130OC Working pressure 0–260 bar (g) Design pressure 0–300 bar (g) Vessel length Approx. 4500 mm Volume 2250 m3 Material carbon and stainless steel ANSI 316 Design code ASME /CE Material certification According to design code Finish all stainless steel parts Pickled and Passivated Positioning vessel Horizontal Medium supercritical Carbon Dioxide

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Total amount of pressure cycles (fatigue load) 25.000 (0–260 bar) Beam width 80 in. Max Load per dyeing vessel Approx 150–180 kg Average dyeing time 2.5–3.0 hours Test performed Hydrotest and NDT according to design code requirements Electrical power 3x400V, 50 Hz, -N, -PE Floor space needed (total machine) Approx. 12 × 12 × 5 Total weight Approx. 90 tons The dyeing machines are equipped with maximally 3 dyeing vessels and are connected to a CO2 recovery and supply unit. These three dyeing vessels are able to dye textile simultaneously, but sequentially pressurized or depressurized. A dyeing cycle is divided into five steps: Step 0: Atmospheric – the dyeing vessel is not under pressure Step 1: Pressurization – the dyeing vessel will be filled with CO2 Step 2: Dyeing and levelling – the textile will be dyed Step 3: Rinsing – the dyeing vessel and the textile will be rinsed Step 4: Depressurization – the dyeing vessel will be depressurized The operator has to choose which dyeing vessel should start with pressurization (step 1) and select the dyeing time. Then the control system takes it over and executes automatically the remaining steps (2, 3, 4, 0) for the activated dyeing vessel (s).

3.4 CO2 dyes Using supercritical fluid CO2, polyester and other synthetics can be dyed with modified disperse dyes. The supercritical fluid CO2 causes the polymer fiber to swell allowing the disperse dye to easily diffuse within the polymer, penetrating the pore and capillary structure of the fibers. The viscosity of the dye solution is lower, making the circulation of the dye solutions easier and less-energy intensive. This deep penetration provides effective coloration of polymers which are characteristically hydrophobic. Dyeing and removing excess dye are processes that are done in the same vessel. Residue dye is minimal and may be extracted and recycled. Supercritical CO2 dyeing gives excellent results as far as dye levelness and shade development, and the physical properties of dyed yarns are equivalent or better to conventional methods.



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Conventional textile dyeing is very water and energy intensive in pretreatment, dyeing, and post-treatment (drying). The supercritical CO2 process involves the use of less energy than conventional processes, resulting in a potential of up to 50% lower operating costs. At this moment the only overlap is in the pre-treatment process, which is essentially the same for both. Our type 2 dyeing machines will be able to avoid the pre-treatment step as well. Together with our partner Triade Chemicals in the Netherlands, we have a complete range of CO2 dyes available for our dyeing machines. Advantages: • Elimination of water consumption • Elimination of wastewater discharges • Wastewater treatment process eliminated • Elimination of drying and dryer effluent • Reduction in energy consumption • Reduction in air emissions • Reduction in dyeing time • Surfactants and auxiliary chemicals in dyes eliminated • Dye utilization is very high with very little residue dye. Unused dye can be recaptured • Approximately 95% of used CO2 will be recycled • Fewer redyes are required • Color correction is easier compared to aqueous dyeing. That might be a fitting twist on Nike’s iconic slogan after recent announcement that it is adopting a waterless dyeing technology that uses recycled carbon dioxide to color synthetic textiles. The process, which the company has been exploring for 8 years, could eliminate the use of countless billions of gallons of polluted discharges into waterways near manufacturing plants in Asia, where much of the world’s textile dyeing occurs. On average, an estimated 100–150 litres (about 26–40 gallons) of water is needed to process 1 kg (2.2 pounds) of textile materials. Industry analysts estimate that more than 39 million tons of polyester will be dyed annually by 2015. The waterless dyeing process, developed by Netherlands-based DyeCoo Textile Systems – the name “DyeCoo” comes from conflating “dyeing” with “CO2” – will begin to show up on Nike products later this year. It utilizes a supercritical fluid carbon dioxide, or SCF technology, so called because it involves heating carbon dioxide to above 31°C (88°F) and pressurizing it. At that stage, it becomes supercritical – a state of matter that can be seen as an expanded liquid or a heavily compressed gas. DyeCoo’s process was launched last fall after 11 years in R&D. Water is

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Textiles and environment

used as a solvent in many textile pretreatment and finishing processes, such as washing, scouring, bleaching, and dyeing. Water scarcity and increased environmental awareness are global concerns. Textile coloring and treatment accounts for between 17 percent and 20 percent of global industrial pollution, according to The World Bank, including 72 toxic chemicals in water solely from textile dyeing, 30 of which are cannot be removed using conventional treatment techniques. SCF CO2 technology already is utilized at scale in other industries such as the decaffeination of coffee and the extraction of natural flavors and fragrances. DyeCoo is believed to be the first company to successfully apply the SCF CO2 process to the commercial dyeing of polyester fabric, and research is underway to apply the technology to cellulosic and synthetic fabrics. Making the switch “wasn’t that difficult,” Eric Sprunk, Nike’s VP of Merchandising and Product, told me recently. “The biggest resistance was an investment in the way things are done today. But I don’t think it’s going to be difficult going forward to dye textiles using zero water. That’s an easy sell for anyone in the apparel industry.” Moreover, he said, the cost wasn’t prohibitive. While Sprunk wouldn’t disclose the price differential for the waterless technology, he said, “We’re not going to be at a cost-disadvantage almost from the get-go.” In conventional textile dyeing large quantities of wastewater are produced. This environmental and economical burden is avoided when supercritical carbon dioxide is used as dyeing medium instead of water. Separating residual dye from the CO2 and recycling of CO2 are easy. Energy is saved because textiles do not need to be dried after the dyeing process. An additional advantage of scCO2 is the high diffusivity and low viscosity that allow the dye to diffuse faster towards and into the textile fibres. This results in a faster dyeing process. Textiles can be classified into non-polar, synthetic polymers (e.g. polyester) and polar, natural textiles. The second category can be divided into polymers built from amino acids (e.g. silk and wool) or cellulose (e.g. cotton). In polyester dyeing, scCO2 penetrates and swells the fibres, thereby making them accessible for dye molecules. Upon depressurization, the dye molecules are trapped inside the shrinking polyester fibres. Polyester dyeing in scCO2 has been studied by several researchers [1–3]. In natural textiles, the dye molecules can be fixed by either physical (e.g. Van der Waals) or chemical (e.g. covalent) bonds. Since the dyes used in a scCO2 dyeing process are non-polar substitution as shown in reaction for hydroxyl containing textile: In the experiment, a small amount of water was added to the scCO2. This was done because it has been shown for vinylsulphone dyes that water facilitates the dyeing reaction and/or enhances the accessibility of the fibres



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by acting as a swelling agent. The water concentration in this work was so low that all the water was dissolved in the scCO2 and the textile. No liquid water was present in the dyeing vessel. Four factors play a role in reactive dyeing of natural fibres in scCO2: 1. Solubility of the dye in the scCO2 at the process pressure and temperature 2. Accessibility of the porous fibre structure to allow diffusion of dye molecules into the pores 3. Affinity or substantivity between the textile and the dye so that dye molecules can approach the textile surface close enough for the reaction to take place 4. Reactivity of dye with the textiles. The dye has to form a covalent bond with amino groups of proteins or with hydroxyl groups of cellulose. Since pressure has an influence on dye solubility, and temperature has an influence on at least solubility and reactivity, both parameters can be investigated. The aim of this work is firstly to test the applicability of a dichlorotriazine dye for polyester, silk, wool, cotton and aminated cotton in moist scCO2 and secondly to determine the influence of pressure and temperature on the dyeing process.

4 New concepts in eco-friendly processing

4.1 Introduction Now-a-days more and more textile and chemical companies are optimizing their corporate social responsibility (CSR) codes by producing green textiles. Among such chemical companies, DuPont is one such example of a successful CSR firm. Earlier it was relying heavily on fossil fuels to make paint, plastics and polymers. In the 1990s, it emphasized on its R&D activities and created products such as nylon; the company decided to spend billions of dollars on developing safe, environment-friendly products. Since then, it has cut greenhouse gas emissions by 72% and air carcinogen emissions by 92% at its facilities worldwide, according to Dawn Rittenhouse, DuPont’s director of sustainable development. The company vowed to generate revenue of US$2 billion a year by 2015 from 1,000 products that would save energy and reduce pollutants. “What’s good for business,” Rittenhouse said, “must also be good for the environment and for people worldwide.” For those who are reluctant to change, the pressure from the public is growing as more retailers are responding to a rising demand for eco-friendly textile and apparel goods from environment-conscious manufacturers. Wal-Mart, the world’s largest retailer, recently announced that it would soon expect its suppliers to utilize eco-friendly processing on products ticketed for its shelves. This proclamation would undoubtedly have a tremendous effect on the way future textile products are manufactured. There is considerable work currently being done in the area of ecoprocessing. Dr Fred Cook, professor and former director of the School of Polymer, Textile & Fiber Engineering at the Georgia Institute of Technology (Georgia Tech) and member of the operating board of the National Textile Center (NTC), suggested that the key for the eco-friendly processing in the chemical and auxiliary industry was the elimination of organic solvents. Other initiatives include the elimination of chemicals altogether. Some efforts are being made to eliminate water, utilizing liquid CO2 as the medium to carry dyes, pigments and more. Dr Cook said research was currently underway at Georgia Tech with “nano dots.” These extremely small metal particles are about 10–9 m in size, which makes the particles about the



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21

size of visible light. If the particles are of the same size as the blue rays, they would reflect yellow. When these particles are embedded in fibre, the resulting fabric becomes a color to the eye, without any use of dyes or pigments. By manipulating the size of these dots, researchers can then create virtually any color fabric. Georgia Tech has discovered that nano-sized scales on the wings of butterflies also cause a reflection of light in certain colors. By emulating this technology and etching nano-sized grooves in the fabric, researchers have been able to provide colorful fabrics with no dyes or pigments.

4.2

Researches for organic processing

Dr Martin Jacobs, Executive Director of the US National Textile Center (NTC), discusses some of the eco-friendly processing research under way at NTC. The NTC is a research consortium of eight US universities: Auburn University, Clemson University, Cornell University, Georgia Institute of Technology, North Carolina State University and Philadelphia University It serves the US industries of fibre technology, textiles and retailing. The NTC has been investigating organic liquids for fibre extrusion under the direction of Dr Roy Broughton of Auburn Engineering. Dr Broughton suggests that cellulose fibres are the most plentiful polymeric fibres in nature. Most cellulose fibres, however, are not long enough to make a fabric. Regenerating cellulose fibres including viscose rayon, cuprammonium rayon, cellulose acetate rayon and Iyocell can solve the length limitation of celluloses. Especially, N-methylmorpholine-N-oxide (NMMO) is acting as a good solvent for newly developed regenerated cellulose fibre, Iyocell except solvent stability and recovery. Applications for the anti-microbial properties on fabrics are diverse. Coating treatment with anti-bacterial chemical is referred as the mainstream of the antibacterial finishing. Due to the relatively low durability of surface treatments, coating of the surfaces is not the most desirable treatment. Other anti-microbials are more toxic or less effective than the halamines under investigation in laboratories. Environmental considerations are now becoming vital factors during the selection of consumer goods including textiles all over the world. However due to increased awareness of the polluting nature of textiles effluents, social pressure is increasing on textile processing units. Awareness about ecofriendliness in textiles is one of the important issues in recent times, since textiles are used next to skin and is called second skin. Owing to the demand of global consumer, researches are being carried out for new eco-friendly technology. Plasma, biotechnology, ultrasonic, super critical carbon dioxide

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Textiles and environment

and laser are quite new technologies for the textile industry. It offers many advantages against wet techniques. There are no harmful chemicals, wet processes, waste water and mechanical hazards to textiles, etc. It has specific action on the all types of fibres and textiles.

4.3

Introduction to eco-friendly processes

Increasing environment consciousness in textile processing has forced research and development efforts to search the safe methods for textile processing. The textile chemical processing plays an important role in controlling the pollution load for environment. Because the textile industry has long recognized that for a large number of process and applications, the surface property is a key aspect of the product and often needs to be quite different from those of the fabric bulk. New applications and improved applicability of many fibres used for clothing, industrial materials and interior decoration require the provisions of new properties in areas such as dyeability, static resistance, current control, stain resistance, water absorption, hydrophilicity, water repellency, adhesive ability and so on. There are surface treatment methods that additionally increase the value of textile materials. The methods can be classified as chemical treatment (wet) methods and physical treatment (dry) methods. Chemical treatment methods are most often used in actual practice. Because of the large amount of energy involved and the high consumption of water and consequently increase of pollution, these techniques are costly and not eco-friendly. In addition, these processes treat the fabric in bulk, something which is unnecessary and may adversely affect overall product performance. Problems related to toxicity and other health hazards have resulted in the replacement of chemical processing by more eco-friendly physical methods. The physical treatment processes are dry, which makes it possible to preserve certain properties intrinsic to textile materials; they are likely to affect the surface of the materials. Therefore the researchers are extensively studying the possibilities of physical surface treatments as alternatives to the chemical treatments. At the beginning, studies initially focused on electron beam irradiation and ultraviolet light irradiation, but electron beam irradiation required too much energy and as a result, properties deteriorated and graft polymerization sometimes occurred. In the latter case it was necessary to find a means of reducing the efficiency of grafting. Ultraviolet light irradiation was tried as a method of resin hardening, but never went beyond the scope of studies on methods of treating fibre surface. In all probability, this was because it offered no specific features superior to what could be obtained with chemical



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treatment. The industry is, therefore, strongly motivated to seek alternative surface engineering processes which could offer low cost, environmentfriendly processing, which is shortly called as eco-processing. Hence, it ecoprocessing is a suitable textile processing method that delivers not only ecofriendly finished products but also does not hamper the environment. Now world around us is fully aware of the implications of the damages already done to water resources and environment due to gas and effluent discharges from polluting industries such as textile and leather processing. In order to reduce and save earth from the pollutions of industries, automotives, etc., there comes in to existence so many world organizations and stipulated norms and standards for the finished goods and the way of operation. Throughout the world almost all countries have formed certain rules and regulations for importing and exporting processed textile goods. Similarly there are many certifying organizations which test and certify that finished goods are up to the mark of importing standards. The certification by these organizations either for the product or for process is called ecolabelling. Some of the eco-friendly suggestions for textile processing are: • Reduce water and energy consumption during preparation, coloration and finishing • Reduce aqueous waste and off-gases • Improve process efficiency • Reduce exposure to hazardous chemicals

4.4

Serving resources in textiles

Some dyes and chemical manufacturers like Huntsman delivers a range of innovative effects, which: • Reduce the amount of energy required in the care of garments • Keep clothes fresher without washing • Keep garments looking new for longer • Reduce or eliminate the need to tumble dry or iron • Eliminate the need to dry clean The goals of cotton textile processing for producing sustainable products are to reduce water use, energy use, and chemical use; use safer/ “greener” chemicals; and minimize inputs to the environment (air, water, solid waste). Post-harvest handling/processing of cotton includes: (1) Yarn manufacture The processes involved in textile manufacturing, such as opening, blending, carding, drawing, combing, if necessary, roving, spinning and winding, are becoming faster and more mechanized. Processing oils is not

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Textiles and environment

usually necessary because of the natural waxes on the surface of cotton. Sometimes biodegradable oils are used in ring spinning, but these oils are removed by fabric scouring and bleaching during preparation prior to dyeing/ coloration. (2) Fabric manufacture Weaving preparation (i.e., direct and indirect warping and sizing) is an important process in the production of woven fabric, especially for high speed weaving, and will continue to be dependent on the future technology of woven fabric production. It requires yarn to be coated with starch or some other ‘size’, prior to weaving for extra strength and abrasion resistance. Sizing is the only operation that may have some environmental concerns in weaving. The size has to be removed during preparation, prior to dyeing and finishing. If starch is used for sizing, it is normally removed with enzymes and scouring. The starch size is not recycled and has to be handled in a manner that does not cause water pollution or other environmental problems. Starch breaks down during the enzymatic treatment and is removed by washing. It consumes oxygen thus lowering oxygen (biological oxygen demand, ‘BOD’) in the wash-off water. Polyvinyl alcohol size, commonly used in conventional sizing, can be removed by scouring and can be recycled. It is, therefore, considered to be more environment-friendly than ‘natural’ starch. There is research underway on size-less weaving, but there are no commercially available processes. Sizing is not required in the manufacture of knitted fabrics, but knitting oils are usually used. They are removed during normal scouring and bleaching in preparation for dyeing/ coloration and finishing. Non-woven fabric manufacturing does not require the use of natural or synthetic sizes either but various additives when used would need to be considered natural. (3) Textile wet processing (preparation/pre-treatment, coloration (dyeing/ printing), and finishing) • Preparation/ pre-treatment – Typically, in preparation for dyeing or printing and finishing, raw (greige) fabric is singed, desized, scoured, bleached, and mercerized (Cotton Dyeing and Finishing: Technical Guide, Cotton Incorporated, Cary, NC, 1996). These treatments remove natural non-cellulosic constituents/impurities and increase the affinity of cellulose for dyes and finishes. • Singeing – This process involves removal of fibres projecting from the surface of the fabric to achieve a smooth surface or yarn. The fibres are normally removed by burning with a flame. • Desizing – Scouring removal of polyvinyl alcohol size which can be 99% recycled. Enzymatic removal of starch sizes. Desizing ingredients such as starch are used as strengthening and protection agents coating



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warp yarns during industrial weaving. Sizing ingredients must be completely removed prior to bleaching and dyeing or printing. This desizing step is critical to ensuring an even and consistent fabric finish. Desizing with Genencor’s amylase enzymes is much more effective, cost efficient, and eco-friendly for manufacturers than chemical desizing methods. Treatments with acids, hot alkali, or oxidizing agents tend to create waste of as much as 50 percent unusable water due to the high biological oxygen demand (BOD). • Scouring – Caustic soda (sodium hydroxide) is commonly used in scouring to remove natural waxes and impurities from the fabric. Enzymatic scouring with alkaline pectinase has been reported to be an environment-friendly alternative to conventional scouring that offers water and energy savings and higher whiteness (Ismal et al., 2007, ‘Oxidative and Activator-Agent Assisted Alkaline Pectinase Preparation of Cotton’, AATCC Rev 7(4), 34–39). • Bleaching – To achieve a true white or predictable dyed color, bleaching usually is necessary. Bleaching is done with hydrogen peroxide but without optical whiteners at a temperature over 60°C, which enhances energy consumption. Peracetic acid (Steiner N, 1995, ‘Evaluation of peracetic acid as an environmentally friendly alternative for hypochorite’, Textile Chemist Colorist 27 (8), pp. 29–32) as well as a waterless bleaching system that uses oxygen gas (Mowbray J 2008, ‘Light fantastic’, Ecotextile News No. 17 Aug/ Sep, pp. 22–24) have been reported as alternate and environment-friendly methods for bleaching cotton. Ozone also can be used as another waterless process to bleach cotton. Bleaching removes residual impurities and changes the natural color of cotton fabric to clear white rather than the off-white (i.e. various shades of yellow). Historically, the textile bleaching process requires temperatures of 95°C. In September 2009, Huntsman and Genencor announced the results of their joint development effort: Gentle Power BleachTM. Genencor’s new enzyme allows textile bleaching to occur at 65°C with neutral pH levels. The system is offered to the global textile processing industry by Huntsman and based on unique enzyme innovation by Genencor called Prima-Green® EcoWhite. Extensive applications research of the technology by Huntsman has resulted in the Gentle Power BleachTM system, which: • offers a versatile bleaching technology for all fibres that are temperature and pH sensitive • results in fabrics that have a superior handle compared to conventionally bleached goods, with a permanent soft and natural handle

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Textiles and environment

• provides better dyeing results, thus noticeably brighter shades and potential savings in dyeing cost • leads to savings in energy consumption due to lower treatment and rinsing temperatures • reduces fabric weight loss during the pre-treatment phase

Bleach cleanup

After fabric or yarn bleaching, residues of hydrogen peroxide are left in the bath and need to be completely removed prior to the dyeing process, using a step called bleach cleanup. Incomplete peroxide removal results in poor dyeing with distinct change of color shade and intensity, as well as patchy, inconsistent dye distribution. Bleachwin is the result of collaborative research efforts of GACL and ATIRA (Ahmedabad Textiles Industry’s Research Association) for ecofriendly, chlorine-free textile bleaching process exclusively developed for allhand processing units of India using special grade hydrogen peroxide in place of bleaching powder/sodium hypochlorite. Mercerization

The treatment of the fabric with strong aqueous solution of sodium hydroxide is performed to add lustre, strength and dye absorption properties of the fabric. Fabric appearance and strength are greatly enhanced by mercerization. Dyeing

Fabrics are dyed after preparation. Dyeing also can be done on raw stock /fibre and yarn. Cotton textiles are dyed with a number of dye classes, including reactive, azoic, direct, indigo, pigment, sulphur and vat dyes (Cotton Incorporated, Cotton Dyeing and Finishing: Technical Guide, Cotton Incorporated, 1996). Some current dyeing or printing operations can be substituted with more environment-friendly operations without the overuse of dyes or auxiliary chemicals. There are ‘non-toxic’ dyes that are used on conventional textiles, including some azo-reactive dyes. Low salt-reactive dyeing systems, low bath ratio dyeing machines, and pad batch dyeing systems are also available. Since some operations and treatments cannot be avoided, it is important that energy efficient processing with less use of toxic chemicals and low water usage be utilized. Printing

Printing methods based on water or natural oils are more environment friendly. Printing using heavy metals as discharging agents should be avoided. Digital printing can be done to reduce chemical use.



New concepts in eco-friendly processing

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Finishing

After dyeing/printing/coloration, fabrics are finished – i.e. treated with chemicals to convey attributes such as antimicrobial, softening, flame resistance, soil release, water repellence, stain resistance, durable press/wrinkle resistance/easy-care, cellulose enzymes to improve hand (biofinishing), etc. Finishing is the final step in the fabric manufacturing process – the last chance to provide the aesthetic properties to add to the customer values. Finishing completes the fabric’s performance and gives its special functional properties. Most dyeing and finishing processes cannot be avoided if cotton textiles are to have the acceptable aesthetics. The conventional dyeing and finishing processing systems at textile mills can pollute the environment if proper practices, including effluent guidelines and air emissions controls, are not followed. The resultant effluent should be treated in a waste water treatment process at the dyeing and finishing plant prior to being emitted as an effluent. Some textile facilities are using biological waste water treatment systems. The effect of chemicals on workers’ health can also be a concern if proper labor/workplace occupational health and safety regulations are not followed. Genencor’s cellulases improve fabric appearance by removing surface fibrils and pills and reducing dead and immature cotton. This prevents subsequent pilling during wash and wear upgrading overall textile quality. Biofinishing creates a smoother fabric surface resulting in fabric that is softer to the touch and drapes better. In addition, PRIMAFAST® LUNA products preserve fabric color by minimizing shade changes during biofinishing and improving fabric strength retention. These benefits allow biofinishing to be completed after the dyeing process.

4.5

Dow Corning and denim processing

Dow Corning has a water- and energy-saving eco-solution for denim processing and a premium hydrophilic softener. Dow Corning GP 8000 Eco Solution has been designed to save up to 50 litres of water on every pair of jeans. Using a unique combination of properties, the new softener is said to eliminate separate washing requirements, thus reducing water usage, energy requirements, utility costs, and processing time, while at the same time increasing productivity. Genencor has recently launched its new range of ‘PrimaGreen’ cellulase, laccase and esterase enzyme products for textile processing. These allow combined denim abrasion, color adjustment and bleaching processes at lower temperatures, mild pH conditions and with significant less use of water. They operate from the vision that they can enable the textile processing industry

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to be more sustainable, and all their research efforts are geared towards this. They are currently developing new finishing technologies for the textile industry, which reduce chemicals, water usage, energy consumption and work under much milder conditions – their solutions tackle specific needs and enhance performance – e.g. their recent first-to-market enzymatic bleaching technology – the key component in the Huntsman Gentle Power Bleach system – yields better product results than existing technologies.

5 Environmental impact solutions

5.1 Introduction Today’s consumers demand that manufactured goods must not only meet quality and safety requirements, but also be sourced and manufactured using sustainable practices that do not adversely impact the environment, community, society or economy. In the current global economy, consumers look for environment-friendly products and packaging produced by companies that uphold environmental best practices, creating added pressure to assess and manage carbon footprint and environmental impact. Whether focusing on greenhouse gas (GHG) emissions or the wider environmental impact of your products – be it water footprint, waste consumption or energy consumption – measuring and communicating your environmental impacts is essential to design your product, packaging and environmental strategy in order to maintain a competitive advantage and to meet market demands. Many countries have their own local carbon label initiatives that require the placement of environmental information on products. As a result, retailers, brands and suppliers need to understand the various requirements from country to country in order to collect appropriate information along their supply chains. The new Sustainable Solutions Suite helps companies reduce the environmental impact of their supply chain processes by offering a range of services from package design to network optimization and simulation, to Greenhouse Gas (GHG) footprinting. In a 2007 survey by the nonprofit group Sustainable Packaging Coalition and Packaging Digest magazine, 73% of 1,255 respondents who are involved in packaging reported that their companies had increased the emphasis on sustainable packaging. However, most of the attention has been focused on minimizing the carbon footprint through creative transportation, alternative fuels and sustainable packaging efforts. The new solution applies that same methodology to its sustainability efforts by reducing all GHGs rather than just the dominant element of carbon. A common misconception that plagues sustainability programs today is that implementing more sustainable processes translates to an increase in cost, when in fact it can significantly reduce the total landed cost of a product.

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By considering things such as GHG emissions during manufacturing and logistics, along with package design, material costs and recycling of returned products or parts, many companies can achieve a cost savings. Using the Sustainable Packaging tool and in conjunction with other industry standard tools, we can measure and analyzes the amount of carbon emissions of various packaging types and provide customers with feedback as to whether or not their traditional packaging is eco-friendly. Environmental and climate challenges are global, and all our customercountries face the daunting task of having to address them as a major priority. In February 2011, the EU reaffirmed its goal to reduce greenhouse gas emissions by 80–95 per cent by 2050 to avoid a temperature increase of 2°C. Taking into account the measures developing countries will have to take, this represents a global reduction in emissions of 50 per cent by 2050. Moreover, 50 per cent of the world’s population currently lives in urban environments. In 20 years, this is expected to grow to 60 per cent. Cities devour energy and resources and produce large volumes of waste. For escalating urbanisation to be sustainable, new solutions and ideas will be needed. Every industry is looking for ways to effectively transition to a more sustainable society. As a result, energy-efficient solutions are in growing demand, regardless of the energy source. Information and communication technology (ICT) is thought to have excellent potential to reduce CO2 emissions if used optimally. It has to be facilitated a leap into the greentech market. New concept is to create and introduce sustainable solutions for various situations where people impact of the environment. This includes cities, energy supplies, transports and traffic on land, at sea and in the air. Transport, energy, water, waste management and huge amounts of information flow in various directions. Several of the players responsible for this in society are the customers. There are systems that can optimise these flows and represent an important step toward a sustainable society. Examples include: • Intelligent transport solutions for air, land and sea • Solutions that improve logistical and maintenance efficiency • Communication and decision-making systems • Surveillance systems for land and sea • Data processing and visualisation for better decision guidance • Waste and energy

5.2

Protect your data and your planet

Learn how a multitier architecture can help the environment and your bottom line. If you’re like most organizations, you’re faced with rising costs, reduced



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budgets, and concerns about staying eco-friendly. Data center power, cooling, and space requirements are becoming a challenge. And the demands for data protection, including improved restore performance, longer data retention times, and integrating technology such as deduplication, are growing exponentially.

5.3

A commitment to the environment

It is dedicated to minimizing the environmental impact on both the development and delivery of its solutions. It is in full compliance with RoHS restrictions, tracks the removal of several materials beyond the RoHS requirements, and is pursuing the removal of all brominate materials in new product designs. It has established WEEE compliance in August 2005, and planning is under way to implement the EU Energy Efficiency Action Plan, which seeks to reduce energy consumption by improving energy efficiency. It is a member of multiple industry associations that focus on minimizing environmental impact. Simply by using an innovative multitier architecture, you can stay environment-friendly while maximizing your resources and your budget. In the conscience-focused marketplaces of the 21st century, the demand for ecofriendly products is increasing amongst end-users. Local and international environmental regulations have emerged, obliging manufacturers and retailers to re-evaluate their environmental and carbon footprint. Adopting an ecodesign approach can help you improve the environmental impacts of your products and therefore enable you to comply with the legislation. So how can you comply and benefit. The Electrical and Electronics (E&E) market has been using Environmental Assessments (Product Life Cycle Assessment (LCA) Footprints) and Declarations (Product Ecological Profiles – PEPs) to demonstrate environmental impacts, and improvements, for their E&E products for many years. Clients in other consumer product sectors are also now using LCA footprints and software to identify a product’s environmental impact – including carbon footprint – in order to develop improvement solutions. Complying with the EU’s Ecodesign for Energy using Product (EuP) Directive requires you to demonstrate knowledge about your product’s environmental assessment (LCA Footprint) as well as the energy usage. The LCA software can assist in simply identifying impact and energy usage whilst advising on how to improve the impact. Designing “green” products is a first step: you also need to let your customers know about it. The environmental experts will help you define a relevant communications strategy, assisting you with the labelling of consumer products and with your Environmental Product Declarations (ISO 14025).

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EIS is a design management process that takes into account the environmental impacts of a product during its whole lifecycle, including the following phases: procurement, manufacturing, distribution, use and end of life. To help our customers implement a comprehensive approach, Intertek offers a range of environmental impact solutions that include: • Product life cycle assessment (LCA) – Intertek offers Simplified LCA, Streamlined LCA and Full LCA studies according to ISO 14040:44 to meet your specific needs. LCAs can allow brands, manufacturers and retailers to better understand the environmental impacts of their products like Carbon Footprint, GHG, Water Footprint during all of the stages of a product’s life cycle. LCAs can be used to facilitate more informed decision making in product development, identify opportunities for optimization and cost reduction in the supply chain and help validate environmental claims and compare products. • Chemical and wastewater management for textile and apparel industry – Intertek offers seamless implementation of a comprehensive chemical management program based on the 3 key elements: people, product, and facility / mill. It includes training and capacity building, assessing and mitigating chemical risks through Chemical Inventory Assessment, testing wastewater effluents, product safety regulation testing such as Registration, Evaluation, Authorisation and Restriction of Chemical substances (REACH) and Substances of Very High Concern (SVHC), Consumer Product Safety Improvement Act (CPSIA) and Restricted Substances Lists (RSL), and Intertek Chemical Certification to make sure chemicals used in manufacturing do not contain hazardous substances. • Eco-product certification – Intertek’s Green Leaf Mark for consumer goods can be licensed by customers to communicate the environmental activities and claims of their products and processes. Intertek also evaluates, certifies and verifies environmental claims about materials used in their products. Intertek also facilitates eco-labeling, product declaration certifications and environmental labeling services to enable customers to make validated claims as well as comply with the Federal Trade Commission. • Intertek’s Recycled PET (R-PET) certification – It is used to ensure that textiles claiming to contain R-PET versus virgin PET are making an accurate representation.

6 The world of eco-fibres

6.1 Introduction The concept of eco-fibres is not new – Henry Ford of the Ford Motor car company wore a suit made of [soya] fabric in the 1940s. He even considered a car made of soy plastic. The subsequent rise of man-made fabrics and plastics put the development of these fabrics on the back burner. As a result of this, not much has been heard of these [natural fibres] until recently. Recognition of the environmental problems caused by man-made fibres has resulted in the emergence of a large number of alternate yarns, and an increasing numbers of producers and consumers are eager to explore these options. An eco-fibre is simply a textile [fibre] that does not employ pesticides and/ or chemicals in the process of growth. The core philosophy of its development is minimal ecological damage. Several new age fabrics have been developed from natural and renewable resources and many more are in the pipeline. But is the production of these fibres actually as benign as is made out? The current lack of a common definition for eco, sustainable, and green fibres makes it difficult for organizations to make informed fibre choices. In accordance with their company objectives, organizations will need to determine and define what goals and parameters to set around their choice of sustainable fibres.

6.2

Characteristics of eco-fibres

Eco-fibres are



• naturally disease-free, resistant to fungal infestations, moulds, mildews and other such infections • often better insulators than man-made fibres • more absorbent than man-made fibres • do not contain chemicals and are naturally less irritating than manmade fibres • often hypo-allergenic • eco-friendly • made from renewable resources

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The advantages listed above most often apply to more traditional EcoFibres extracted from natural plants like [bamboo], [hemp], [soy] and so on.

6.3

Classification of eco-fibres

Eco-fibres are of four broad types:





1. Natural origin eco fibre – Organic cotton, organic silk, Ahimsa silk, organic wool, Hemp, bamboo, Kenaf, jute, Sasawashi, Nettle, Sisal, Coconut fibre or Coir, [Banana] fibre, Ramie and Mesta/Roselle. 2. Highly processed natural origin fibre – Rayon type: Modal, Lyocell/ Tencel, Ingeo, Seacell. 3. Fibres from waste products – These are often obtained from food waste products. For example, crab shell fibre or chitin from crab shells and soy fibre from soy kernels after tofu has been made. Recycled plastic bottles are also a source or fibre for 100% recycled clothing. 4. Eco-fibre blends – Creora, Lycra blends

6.4

Natural origin eco-fibre

Natural fibres are subdivided into two classifications: animal (protein) fibres and plant (cellulose) fibres. (a) Protein fibres include wool, cashmere, alpaca and even silk. (b) Cellulose fibres are produced by plants, and are products of agriculture. Fibres are either bast fibres (the fibre surrounding the stem of the plant such as flax or hemp), or seed fibres such as cotton. The varieties of natural fibres are: • Cotton is arguably the world’s most comfortable and versatile fabric. Its present production technique however is extremely environmentally damaging. The growing of cotton uses 25% of the world’s annual pesticides employed. • Organic cotton is grown to a certified organic standard, without the use of toxic and persistent pesticides or fertilizers, sewage sludge, irradiation or genetic engineering, and is certified by an accredited independent organization. It is a system of farming that strives for a balance with nature, using methods and materials that are of low impact on the environment. The impact on people and ecosystems is considerably less than in the production of conventional cotton. As with all organic fibres, certification may apply only to the way the fibre is grown, or to the full production process. • Recycled cotton – Cotton can be recycled from two sources: spinning waste is recycled in the same spinning plant; this is often mixed with



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virgin cotton to achieve a usable yarn. Various types and percentages of waste fibres – scrap yarn, scrap fabric, garment – fall out and scrap garments can be processed and recycled into yarn. • Pakucho or colour grown cotton – This is amazing precoloured organic cotton that comes from a traditional Andean source. The cotton plant produces precoloured cotton that grows in the natural shades of white, tan, green, yellow, red, and brown. This cotton was unsuited to modern cotton spinning and weaving machinery and was not used as a result. It is only in the 1990s that this was employed to provide low impact, exceptionally lovely fibre. The most amazing thing about this is that colour grown cotton is actually colour fast! • Silk – Wild silk, sometimes known as “Tussah Silk” is produced from silkworms that feed on the leaves of dwarf oak trees and are allowed to live out a complete lifecycle in their natural habitat. The silkworms are humanely cultivated, meaning the wild silk cocoons are only processed using natural methods and only after the moth emerges naturally from the cocoon. Humanely produced silk is also known as “Peace Silk.” Conventional silk is derived from silkworms that feed largely on mulberry leaves, usually indoors in large trays. This type of silk is called “cultivated” and is produced on large, industrial run farms. Cultivation includes the boiling of the cocoon with the worm inside in order to kill the worm before it becomes a moth and emerges from the cocoon. • Organic silk is silk that is cruelty, chemical and dye free. • Silk Noil is silk fibre reconstituted from waste silk and broken silk yarn. This is un-bleached and un-dyed and is available is various natural shades ranging from off-white to deep gold. • Ahimsa silk is also referred to as vegetarian peace silk. • Wool is the protein fibre that is typically from sheep, although other animals such as goats or llamas can also produce wool. In order for wool to be certified as organic, the animals must be raised according to an accredited organic standard for organic livestock production. There are other environmental forms of wool that address animal husbandry, land management and processing. These tend to be private company standards and will vary accordingly. • Alpaca wool is a highly prized woollen fibre because of its natural hollow core. This provides superior insulation and warmth. The produce of Alpaca herds reared only for their wool (not their meat), in areas that are close to weaving and spinning centres would classify as eco-fibres. • Organic wool, according to the USDA or the United States Department of Agriculture, is wool that is sheared off sheep raised

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•



•



•



•

6.5

without hormones, grazed on land that has not seen [pesticide] usage and has not been overgrazed. Additionally, the sheep feed is required to be organic, and the rearing must be under continuous organic management from the last third of gestation forward. Linen – Flax, also known as linseed, is the plant that produces the bast fibre that is made into linen. In the United States, certified organic flax seed for oil is grown, however, textile-grade flax fibre is imported. Certified organic flax fibre is mostly grown in Europe and China. Organic flax can by certified by any accredited third party certification organization. Bamboo is one of those amazing plants that needs very little water, fertilizers, is naturally regenerative and grows very fast – up to one foot per day. It is also naturally pest resistant. It can produce one of the world’s most exquisite fibres, silky, with a linen-like drape. It is therefore not surprising that it is extremely popular with the producers of green fabrics and clothing. Qoperfina Copper is either high quality certified organic cotton or sometimes organic cotton mixed with organic Alpaca wool. This is in turn is blended with 2% Angelina Copper (metal fibres). The cotton has a [SKAL] or [EKO certification] as does the wool. Products with an EKO certification preclude chemical ingredients on either the land or in association with the animals raised thereon. The fabric is undyed, hypoallergenic and lightweight. The hollow fibre core affords great warmth and therapeutic qualities. Qoperfina is from a registered [fair trade] source. Hemp is one of the most versatile eco-fibres available. Uses of hemp range from fibres for textile products, animal bedding, plastics, paper pulp, clothing and building products. While the idea of hemp does evoke images of rope and dull home-spun clothes, nothing could be further from its modern day avatar! Hemp products include automotive accessories, cosmetics, animal bedding products, fabrics and textiles, papers, oil flavourings, lighter and stronger [biodegradable] polycomposites and many other products. Industrial hemp is also very versatile. Almost all parts of the plant including the [bast fibre], the hurd (inner stem fibres), the seed, the seed oil and other plant extracts are used in industry.

Hemp bio-commodities

Hemp bio-commodities are the processed fractions of hemp stalks. The outer fibre (bast) and interior pith (hurd) can be processed in many ways to produce



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raw materials, or a significant component, in a multiplicity of manufactured Alpaca Wool is a highly prized woollen fibre because of its products. Hemp based bio-commodities have many formats, from crude raw fibrous material through to a highly refined fibre and treated cellulose materials. • Kenaf/ Mesta / Hibiscus/ Rosella is a hemp-like member of the hibiscus family. The cellulose of Kenaf is extracted for the production of green fibres. It is known to be one of the greenest alternatives to [paper] making and has large commercial applicability. There is evidence that Kenaf was domesticated as far back as 5000 BC in Egypt. • Sisal is a variety of hemp and is usually used to make floor coverings. It can be blended with cotton and wool and used in several applications including clothing. • Jute is traditionally used to make rope and has a naturally coarse texture. The finer threads of jute are sometimes used to create imitation silk; and it is being increasingly viewed as an alternative to wood-pulp [paper]. • Sasawashi is a blend of Japanese paper and the Japanese kumazasa herb. It is a fabric that was introduced onto the fashion scene by the clothes designer Linda Loudermilk and is now made into many consumer products including towels. The drape of Sasawashi is very similar to Linen. • Nettle fishing drag-nets were used in Britain up to post-medieval times. The fibre was used in the First World War as a substitute for cotton, to weave soldier’s uniforms. In recent times the nettle has made a comeback and village communities in Nepal and India are weaving exquisite fashion accessories like bags and scarves for international markets. • Ramie is a relative of Nettle and has been similarly used throughout history. A native of China, it is essentially a cloth fibre used as a substitute for cotton. It is also said to have anti-bacterial properties. • Coconut fibre or coir has many uses. It is used to make rope and yarn, aquarium filters, car seat covers, flower pots, used as a soundproofing material, as mulch for plant growing, to provide heat insulation, to make brushes, bristles, mattresses, door mats, matting, rugs, [hand knotted carpets]. • Banana fibre is made from waste banana trees, and is a completely natural, extremely strong fibre. An Australian technology enabling this also ensures that the final product uses no chemicals, bleaches or glues. The product uses banana sap as glue. Since the product

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does not work on a pulping technique, it uses very little or no water (compared to 55,000 litres of water for every tonne of pulp paper). In addition, the machinery uses very little horsepower so the production can easily utilise solar and wind energy. The product is primarily directed at creating a packaging product. It is grease-proof, water and fire resistant, and totally bio-degradable, meaning it can be fed to livestock or fish after use.

6.6

Regenerated fibres

Regenerated fibres are sometimes known as man-made fibres. This group of fabrics is bio-based rather than natural. These are fibres that have been created artificially by using the building blocks provided by nature (e.g. proteins or cellulose) as opposed to fibres made entirely by nature (e.g. cotton). These products are also bio-degradable. A regenerated fibre would typically be a natural material that has been converted by wet chemical processing that allows the production of continuous filaments that can then be spun into fibre (e.g. viscose). There are two primary types of regenerated fibres: Regenerated fibres from cellulose – Rayon and viscose are regenerated cellulosic fibres. The issue that is often brought up about regenerated fibres is that the processing uses harsh chemicals and is environmentally damaging. Tencel is considered a more environment-friendly regenerated fibre, and it has different properties from rayon. Lyocell/ Tencel is a cellulose-based fabric from farmed trees. It is a solvent spun fibre in which the cellulose is directly dissolved keeping the cellulose much closer to that found in nature. The fibre is sourced from Forest Stewardship Council (FSC) certified forests, and the processing is done in a closed-loop system where very little pollution escapes into the environment. • Modal is a Beech tree based fibre that has a soft and smooth texture that is similar to cotton or silk. • Seacell is also a similar fibre made from seaweed and sea algae. It reputedly has therapeutic qualities. • Regenerated fibres from protein sources are called Azlons and sources of the proteins include soy, corn, peanuts and even milk. Bamboo is used as feedstock to produce rayon. As one of the fastest growing plants in the world, bamboo grows to its maximum height in about 3 months and reaches maturity in 3–4 years. It spreads rapidly across large areas. Because of relatively quick growing time and the ability to be grown without fertilizers or pesticides, the fibre source is currently being marketed as an ‘eco ‘green’ sustainable fibre.’



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There are potential risks associated with using bamboo as a polymer source for rayon, since there is currently a lack of transparency in the supply chain. It is not always clear which type of bamboo is used for fibre, where it is grown, how it is cultivated, how it is harvested, etc. To date, there is no known organic certification of bamboo. The process to make viscose or rayon fibre from bamboo is the same process used to produce viscose/rayon from any other plant source. The cellulose is extracted from the bamboo, and then mixed with chemicals to convert the plant pulp into textile quality fibre. This process can be very polluting unless it is carefully controlled, and can be influenced by the age and condition of the equipment as well as whether there is any by-product recycling or effluent treatment. Note that in most countries, the fibre cannot be called bamboo, only rayon or viscose from bamboo.

6.7

Recycled synthetic fibres

There are fundamentally three questions that should be asked about recycled textiles: what is the origin of the waste, what is the method of converting waste to chips and how do you know the product is produced from recycled materials.

6.8

Recycled polyester

Recycled polyester is polyester that has been manufactured by using previously used polyester items such as PET bottles or used polyester clothing. The benefits of recycling polyester come from the reduced energy needed to produce the final fibre, reduced dependence on oil, and the diversion of waste from landfills. One consideration in the recycling of PET is antimony, which is present in 80–85 percent of all virgin PET. It is converted to antimony trioxide at high temperatures that are necessary during recycling, releasing this carcinogen from the polymer and making it available for intake into living systems.

6.9

Recycled nylon

Like polyester, virgin nylon fibre is made from crude oil. Recycled nylon comes from post-industrial waste fibre and yarn collected from spinning and processed into reusable nylon fibre. The benefits of recycling nylon come from the reduced energy needed to produce the final fibre, reduced dependence on oil, and the diversion of waste from landfills. The final product can be recycled again at the end of its life.

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6.10

Textiles and environment

Fibres from waste products

• Crab shell fibre – Chitosan or Chitin as it is also known, is an amazing fibre made from discarded crab shells. This is most often made into medical bandages. This fibre helps the healing process and helps avoid the formation of scar tissue. • [Soy] fibre is an extremely beautiful fibre that is hand or machine spun from leftover edible soy-bean protein. The fibre is soft and silky and can be bleached or dyed at will. Its natural colour is a lovely gold. Soy bean fibre has antibacterial qualities and has proteins and minerals which apparently improve human health. It does not require chemical fertilizers and is therefore environmentally friendly as well. It is an ecologically friendly alternative to silk. • Recycled plastic bottle fibre – Plastic waste is arguably the most visible environmental scourge of our time. So it is with some relief that consumers have greeted the introduction of fibres made from recycled plastic bottles. Marks and Spencers, the well known British store launched its range of 100% recycled polyester garments made from plastic bottles in 2007. There is a whole range of children’s school wear and fleece wear in this range.

6.11 Blends New products that offer blends of spandex and lycra like materials with eco-fibres like Modal, Lycell, Seacell and so on are also now available. Manufacturers are rethinking their production processes so as to minimise environmental risk and still provide consumers fashionable fits and fall. While these fabrics are not 100% environmentally safe, they are a step in the right direction.

6.12

Drawbacks of using eco-fibre products

• Maintenance: The single largest issue with Eco-Fibres is maintenance. The downside to several novelty fabrics such as Qoperfina is that they contain copper that degenerates if exposed to acids, or chlorine bleaches. They must be hand washed with bio degradable detergents and no bleach. • Reaction to heat: Certain eco-fibres do not react well to heat application including ironing. • Shape retention: Some fibres like bamboo tend to lose shape and stretch too much. • Durability: Some reports state that eco-fibre products are not long lasting. The edges fray and the fabric retches up after some sustained use.



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• Cost: Eco-fibres like bamboo and soy derivatives tend to be priced between 30% and 40% more than their cotton (non-organic) equivalents. • Dyeing: Some eco-fibres do not take well to dyeing.

6.13

Verification

There are now several standards in place that support recycled content claims, developed by third-party certification bodies (e.g., INTERTEK). Some companies provide their own guarantees, while others do not provide any validation and should be treated with care.

6.14

Comparison of fibres

It is very difficult to evaluate the overall environmental impact of one fibre over another; some information is very difficult to access or applies only to a specific region and judgments have to be made on how to weigh the different impacts of the source, production and use of the product. The factors that are generally considered in a full life-cycle assessment of a fibre include energy use, green house gas emissions, water use, land use, toxicity to humans and ecosystems, useful life of the product and final disposal.

7 Hazardous substances in clothing and other textiles

7.1 Introduction Hazardous chemicals are substances that are dangerous to people, wildlife and the environment at any stage of their lifecycle, from production to use to disposal. Many hazardous chemicals are used in factories during the production process, after which they are dumped into rivers and lakes. They can also be an ingredient in the final product, such as plasticizers in plastics or heavy metals in electronics. In 2011, Greenpeace International published two reports: one investigating the discharge of hazardous substances from textiles manufacturing in China linked to major clothing and sportswear companies. The manufacturers of the textiles sector produce clothing and other textiles which enter into the lives of almost all persons on the planet. The sector is an important one for the global economy: in 2003 more than 140 economies produced clothing and textiles for export, and many are highly dependent on these exports for employment. The sector is also one of the most globalized. The series of steps in producing and selling a garment – fabric production, fabric treatment, cutting and final product assembly and transport to market – frequently involve international or intercontinental movements of products. With the global movement of clothing and textiles comes the global movement of whatever they contain. In recent years increased attention has been given to the chemicals which are contained in textiles products. This could be explained by the existing knowledge of the intense use of chemicals by the sector – chemicals are used both for fibre production and during the manufacturing process. Some of the world’s best known fashion retailers are selling clothing contaminated with hazardous chemicals that break down to form hormone-disrupting or cancer-causing chemicals when released into the environment, finds a report issued recently by Greenpeace International in Beijing. Greenpeace International’s investigation report, “Toxic Threads – The Big Fashion Stitch-Up,” covers tests on 141 clothing items and exposes the links between textile manufacturing facilities using hazardous chemicals and the presence of chemicals in final clothing. Tests at Greenpeace Research Laboratories at Exeter University in the United Kingdom and at independent



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accredited labs found hazardous chemicals in clothing from 20 well-known fashion brands. The tests were conducted on jeans, trousers, t-shirts, dresses and underwear designed for men, women and children and made from both artificial and natural fibres. “Hazardous chemicals are both incorporated deliberately within the materials or left as unwanted residues remaining from their use during the manufacturing process,” said Greenpeace International, releasing the report. The clothes tested for the study were sold by fashion companies: Armani, Benetton, Blazek, C&A, Calvin Klein, Diesel, Esprit, Gap, H&M, Jack & Jones, Levi’s, Mango, Marks & Spencer, Metersbonwe, Only, Tommy Hilfiger, Vancl, Vero Moda, Victoria’s Secret. Fashion retailer Zara is the only company that researchers found selling clothes that can give rise to chemicals that are both hormone disrupting and cancer causing when released into the environment. “Some of the Zara items tested came out positive for substances that break down to form cancer-causing or hormone-disrupting chemicals which is unacceptable for both consumers and the people living near the factories where these clothes are made,” said Martin Hojsik, Detox Campaign coordinator at Greenpeace International. One of the world’s largest international fashion companies, Zara says on its website that the company employs an “eco-friendly management model,” working towards energy and waste reduction and recycling. “Zara supports organic farming and makes some of its garments out of organic cotton (100% cotton, completely free of pesticides, chemicals and bleach). They have specific labels and are easy to spot in our shops,” the company says on its site. Hojsik is urging Zara to do more. “As the world’s largest clothing retailer, Zara needs to take the lead and take urgent, ambitious and transparent action to detox their clothes and supply chains.” For the Greenpeace study, a total of 141 items of clothing were purchased in April 2012 in 29 countries and regions worldwide from authorized retailers. All tested brands had at least several items containing nonylphenol ethoxylates, or NPEs. Greenpeace warns that some of the chemicals released, when NPEs break down in water treatment plants or in rivers, were hormonedisrupting chemicals. NPEs were found in 89 garments – just under two-thirds of those tested. The highest concentrations of NPEs – above 1,000 parts per million – were found in clothing items from Zara, Metersbonwe, Levi’s, C&A, Mango, Calvin Klein, Jack & Jones and Marks & Spencer. High levels of toxic phthalates were found in four of the garments. Cancer-causing amines from the use of certain azo dyes were detected in two garments. Both products were manufactured in Pakistan for Zara and sold in either Lebanon or Hungary. The environmental group is asking that manufacturers require their suppliers to disclose all releases of toxic chemicals

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from their facilities to the communities at sites of water pollution. Greenpeace is calling on governments to adopt a political commitment to “zero discharge” of all hazardous chemicals within one generation, based on the precautionary principle and including a preventative approach by avoiding production and use and, therefore, exposure to hazardous chemicals. Greenpeace says in the report, “As a vital first step to this process, a dynamic list of hazardous chemicals should be established and include chemicals like NPEs and phthalates for priority action, and have a publicly available register of data on discharge emissions and losses of hazardous substances.” The items tested were manufactured mainly in Africa, Central and Latin America, and most of Asia, collectively known as the Global South. “Major fashion brands are turning us all into fashion victims by selling us clothes that contain hazardous chemicals that contribute to toxic water pollution around the world, both when they are made and washed,” said Yifang Li, senior toxics campaigner at Greenpeace East Asia. “The textile industry continues to treat public waterways as little more than their private sewers. But our fashion doesn’t have to cost the Earth: Our clothes don’t have to be manufactured with hazardous chemicals,” said Li. Greenpeace is demanding that fashion brands commit to zero discharge of all hazardous chemicals by 2020 – as brands including H&M and M&S have already done. A RSL is a list of chemical substances which a company wishes to eliminate or to keep below a required concentration in their products. Generally it is the company who puts the products on a market, frequently a brand name, which specifies the RSL program parameters and mode of functioning. Suppliers to the company must put in place measures to ensure their manufactured products comply with the RSL’s requirements. These initiatives often entail training of suppliers, routine and random product testing, certification of compliance that suppliers further upstream are supplying appropriate chemicals and other measures designed to ensure the program’s integrity are common features of an RSL program. It is notable that under an RSL program the information on what chemicals are not in the product – that is the product’s “negative content” information – does not accompany the product itself, but is often made available through other channels (e.g. the company’s website). Ecolabels can have many of the same features as a RSL program. Indeed, a chemical-oriented textile ecolabel must derive the validity of its claim for ‘safer products’ from a rigorous set of requirements, including oversight and reliable testing. As ecolabels are generally attached to the finished article, the negative-content information does accompany the product. The study focused predominately on clothing, laundry, and another detailing the presence of



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NPEs in clothing and footwear of 15 leading brands (Dirty Laundry: Hung Out to Dry). With the publication of these reports Greenpeace challenged global brands to eliminate all releases of hazardous chemicals from their supply chains and products by 2020. The Detox Campaign, as it is now known, is especially targeting Chinese manufacturers. With nearly 50,000 textile factories, the “factory of the world” is in fact the first victim of textile water pollution, prompting even the government to face up to the problem. “China is moving toward legislation where each company is responsible for its wastewater,” said Ulrike Kallee. “Awareness is now very high.” The manmade chemical by-products of the textile industry are shown to have long-term effects on the environment and potentially devastating impacts on human and animal life. Furthermore, when testing clothing from 15 corporate brands, Greenpeace found that the chemicals used in the textile production process continue to be released when contaminated clothing is purchased and washed by consumers across the world. These tests demonstrate the truly global danger posed by these toxic chemicals as they are released into rivers and water sources from the point of production to the consumer. I don’t know why there is not an outcry about the clothing which is continuing to contaminate wash water – doesn’t it occur to people that clothing contains chemicals which are being absorbed by our skin and causing us harm? For that matter, think about the fabrics we subject ourselves to intimately every day, like sheets and towels. Where is the disconnect here? Greenpeace’s Detox Campaign is helping create a greener economy by challenging major global brands to rid their textile production processes of hazardous chemicals. The Detox Campaign has already successfully demonstrated the power of grassroots activism and social media in pressuring corporations to clean up their production practices. Only months into the Detox Campaign, major retailers H&M, Puma, Adidas and Nike committed to eliminating discharges of hazardous chemicals across their supply chains by 2012; most recently Marks & Spencer joined the group. In addition to pressuring corporations to adopt greener production practices, Greenpeace is pursuing legislative changes within the textile industries in several Asian countries and the European Union in order to protect rivers and the communities and ecosystems they support. Patty and Leigh Anne founded this company to make the whole world safer while making our personal environments more beautiful. After forming O Ecotextiles in 2004, they began a world-wide search for manufacturing partners interested in a cradle-to-cradle process of creating no-impact, perfectly safe, incredibly luxurious fabrics.

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They began working with people around the world: Romanian farmers who dew- or field-ret hemp stalks; a Japanese mill owner committed to “green” processes, even new methods such as using ozone to bleach fabric; a 100-year-old Italian mill that produces no wastewater; a Chilean mill shifting to entirely green processes; an Italian dye house that produces biodegradable, heavy metal free textiles. The first fabrics coming out are, as the sisters envisioned, sophisticated, stylish and “green.”

7.2 Alkylphenols Commonly used alkylphenol compounds include nonylphenols (NPs) and octylphenols and their ethoxylates, particularly nonylphenol ethoxylates. NPs are widely used in the textiles industry in cleaning and dyeing processes. They are toxic to aquatic life, persist in the environment and can accumulate in body tissue and biomagnify (increase in concentration through the food chain). Their similarity to natural oestrogen hormones can disrupt sexual development in some organisms, most notably causing the feminisation of fish. NPs are heavily regulated in Europe and since 2005 there has been an EU-wide ban on major applications.

7.3 Phthalates Phthalates are a group of chemicals most commonly used to soften PVC (the plastic polyvinyl chloride). In the textile industry they are used in artificial leather, rubber and PVC and in some dyes. There are substantial concerns about the toxicity of phthalates such as DEHP (Bis (2-ethylhexyl) phthalate), which is reprotoxic in mammals, as it can interfere with development of the testes in early life. The phthalates DEHP and DBP (Dibutyl phthalate) are classed as ‘toxic to reproduction’ in Europe and their use is restricted. Under EU REACH legislation, the phthalates DEHP, BBP (Benzyl butyl phthalate) and DBP are due to be banned by 2015.

7.4

Brominated and chlorinated flame retardants

Many brominated flame retardants (BFRs) are persistent and bioaccumulative chemicals that are now present throughout the environment. Polybrominated diphenyl ethers (PBDEs) are one of the most common groups of BFRs and have been used to fireproof a wide variety of materials, including textiles. Some PBDEs are capable of interfering with the hormone systems involved in growth and sexual development. Under EU law, the use of some types



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of PBDE is tightly restricted, and one PBDE has been listed as a ‘priority hazardous substance’ under European water law, which requires that measures be taken to eliminate its pollution of surface waters.

7.5

Azo dyes

Azo dyes are one of the main types of dye used by the textile industry. However, some azo dyes break down during use and release chemicals known as aromatic amines, some of which can cause cancer. The EU has banned the use of these azo dyes that release cancer-causing amines in any textiles that come into contact with human skin.

7.6

Organotin compounds

Organotin compounds are used in biocides and as antifungal agents in a range of consumer products. Within the textile industry, they have been used in products such as socks, shoes and sport clothes to prevent odour caused by the breakdown of sweat. One of the best-known organotin compounds is tributyltin (TBT). One of its main uses was in antifouling paints for ships, until evidence emerged that it persists in the environment, builds up in the body and can affect immune and reproductive systems. Its use as an antifouling paint is now largely banned. TBT has also been used in textiles. TBT is listed as a ‘priority hazardous substance’ under EU regulations that require measures to be taken to eliminate its pollution of surface waters in Europe. From July 2010 and January 2012 products (including consumer products), containing more than 0.1% of certain types of organotin compounds will be banned across the EU.

7.7

Perfluorinated chemicals

Perfluorinated chemicals (PFCs) are manmade chemicals widely used by industry for their non-stick and water-repellent properties. In the textile industry, they are used to make textile and leather products both water and stain-proof. Evidence shows that many PFCs persist in the environment and can accumulate in body tissue and biomagnify (increasing in levels) through the food chain. Once in the body some have been shown to affect the liver as well as acting as hormone disruptors, altering levels of growth and reproductive hormones. The best known of the PFCs is perfluorooctane sulphonate (PFOS), a compound highly resistant to degradation; it is expected to persist for very long periods in the environment. PFOS is one of the ‘persistent organic pollutants’ restricted under the Stockholm Convention, a global treaty to protect human health and the environment, and PFOS is also prohibited within Europe and in Canada for certain uses.

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7.8 Chlorobenzenes Chlorobenzenes are persistent and bioaccumulative chemicals that have been used as solvents and biocides, in the manufacture of dyes and as chemical intermediaries. The effects of exposure depend on the type of chlorobenzene; however, they commonly affect the liver, thyroid and central nervous system. Hexachlorobenzene (HCB), the most toxic and persistent chemical of this group, is also a hormone disruptor. Within the EU, pentachlorobenzene and HCB are classified as ‘priority hazardous substances’ under regulations that require measures to be taken to eliminate their pollution of surface waters in Europe. They are also listed as ‘persistent organic pollutants’ for global restriction under the Stockholm Convention, and in line with this they are prohibited or scheduled for reduction and eventual elimination in Europe.

7.9

Chlorinated solvents

Chlorinated solvents – such as trichloroethane (TCE) – are used by textile manufacturers to dissolve other substances during manufacturing and to clean fabrics. TCE is an ozone-depleting substance that can persist in the environment. It is also known to affect the central nervous system, liver and kidneys. Since 2008 the EU has severely restricted the use of TCE in both products and fabric cleaning.

7.10 Chlorophenols Chlorophenols are a group of chemicals used as biocides in a wide range of applications, from pesticides to wood preservatives and textiles. Pentachlorophenol (PCP) and its derivatives are used as biocides in the textile industry. PCP is highly toxic to humans and can affect many organs in the body. It is also highly toxic to aquatic organisms. The EU banned production of PCP-containing products in 1991 and now also heavily restricts the sale and use of all goods that contain the chemical.

7.11

Short-chain chlorinated paraffins

Short-chain chlorinated paraffins (SCCPs) are used in the textile industry as flame retardants and finishing agents for leather and textiles. They are highly toxic to aquatic organisms, do not readily break down in the environment and have a high potential to accumulate in living organisms. Their use has been restricted in some applications in the EU since 2004.



7.12

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Heavy metals: cadmium, lead, mercury and chromium (VI)

Heavy metals, such as cadmium, lead and mercury, have been used in certain dyes and pigments, which are used for textiles. These metals can accumulate in the body over time and are highly toxic, with irreversible effects including damage to the nervous system (lead and mercury) or the kidneys (cadmium). Cadmium is also known to cause cancer. Uses of chromium (VI) include certain textile processes and leather tanning. It is highly toxic even at low concentrations, including too many aquatic organisms. Within the EU, cadmium, mercury and lead have been classified as ‘priority hazardous substances’ under regulations that require measures to be taken to eliminate their pollution of surface waters in Europe. Uses of cadmium, mercury and lead have been severely restricted in Europe for some time, including certain specific uses of mercury and cadmium in textiles.

8 Herbal dyeing process

8.1 Introduction In India, people in ancient time used natural and also ayurvedic-based clothes, even now in South India there is a custom that a new born baby is kept in herbal and ayurvedic dyed towels; even Lord Gautam Buddha was wearing turmeric clothes; natural kavi textile was also popular; but unfortunately after 18th century due to the cheap chemicals dyeing materials, textiles manufactures used chemical dyeing and spoiled the land, water and environment, now the global warming is also due to this industrial pollution, increase in various diseases like cancer is also due to the harmful chemical contents in fabrics/ foods/environments. Today almost all the food items have been either polluted or gene modified, even the cow has been genetically modified, so even the milk is not organic. Now the growing awareness about organic and health consciousness among the people has created a big market for organic food / organic clothing etc. In 1996 Germany had banned the toxic chemically dyed fabrics because a research found that many skin diseases are due to toxic dyed clothing, as 50% of pesticides are used for cotton cultivation, and the pesticide is absorbed by the cotton and from the field to fashion all the process including the dyeing was toxic. Subsequently, more than 60 countries had banned chemical-based dyeing. Your skin is the largest, most absorptive organ of your body. What you put on the outside, ends up inside. Let’s wrap ourselves in the goodness of herbs and bring life back to our skin with the ancient knowledge of Ayurveda. The herbal dyeing process is one step ahead of organic textile. The core concept of growing organic cotton is to eliminate the impact of harmful chemicals and pesticides which are used in course of growing it. But does the story of using harmful and carcinogenic chemicals stop here? Certainly NOT. And this is the point from where organic story begins. We have to eliminate the entire conventional system from the said harmful impacts right from growing cotton to getting the end product in most natural and organic way.



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We know many facts of chemical dyeing and the major areas of concern and problems for people with chemical sensitivities purchasing clothing what we found was the dyes and garment finishing. Garment finishes for wrinklefree, stain resistant, flame retardant, anti-fungal, anti-bacterial, anti-static and odour-resistant, permanent-press, non-shrink, softening agents and the other easy care treatments that are applied to new clothing can be especially harmful for people with chemical sensitivities which are basically all of us – it is just the degree of sensitivity that varies. Apart from this, herbal-dyed textiles can also help in preventing the diseases which otherwise are common with conventional clothing. Dyes and garment finishes are known to result in problems like skin rashes, headache, trouble concentrating, nausea, diarrhoea, fatigue, muscle and joint pain, dizziness, difficulty breathing, irregular heart beat and seizures. Symptoms in children include red cheeks and ears, dark circles under the eyes, hyperactivity and behaviour or learning problems. In fact we visited some of the chemical dyeing plant and it was almost next to impossible for us to breath over there. So we were just wondering that under what circumstances the workforce/labours would be working there when we could not manage to stand even for a short while and how this kind of unhygienic and toxic environment would be hazardous and lead to various health related issues of those labours. In fact in the developing countries where industry norms are not followed strictly, we may find these kinds of industries releasing their residues and waste without treating them either directly in deep dug pits in the land or directly in the rivers. And the villagers who depend on river water as their only source become victims of these harmful chemicals and land up with many health-related problems. Clothing comes into prolonged contact with your skin, toxic chemicals are absorbed through your skin and skin pores are opened to permit perspiration. Once absorbed by humans, heavy metals tend to accumulate in the liver, kidney, bones, heart and brain. The effects on health can be significant when high levels of accumulation are reached. The effect is particularly serious in children due to effects on growth and their relatively low body mass. Toxic chemicals from dyes also create severe environmental havoc in form of air, water and soil pollution. Large amounts of water are used to flush conventional synthetic dyes from garments and then this waste water must be treated to remove the heavy metals and other toxic chemicals before it can be returned to water systems, sewers and rivers. And the way global warming is mounting, where textile industry is contributing a lot in terms of green house gases and before it creates havoc we need to generate awareness and take rigid and thoughtful steps against those things which are fuelling such issues.

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So all of the above things made us to think towards the concept called organic and herbal textile. We cannot separate these two concepts because they are incomplete without each other. They both are complementing. So when we say 100% organic or 100% natural, it has to be processed in this way or else there is no meaning of using organic cotton.

8.2

Facts of chemical processing

• Use of different 8000 chemicals in various stages in chemical dyeing. • As high as 40 times the weight of the fabric, water is required to process the same. • Most of the so-called eco-friendly dyeing or low impact dyeing available on organic as well as conventional cotton is still being dyed using huge amount of chemicals and dyes but in permissible limits. Thus they may be of low impact but certainly not ‘no’ impact. • The eco-cycle or organic textiles can only end with true organic processing where the waste is reused for e.g. in form of manure. Since most of the organic textile available in the market is still processed and dyed using loads of chemicals, even if it is so-called azo-free or low impact chemical dyes we searched further. The herbal dyeing process is completely chemical free and thus one step ahead of organic textile. The process of herbal dyeing starts with the grey cloth passing through several stages of treatment before it becomes colourful and ready to wear. The process of herbal dyeing was developed through extensive research during the age-old dyeing methods practiced since the days of the Indus civilization. The process of herbal dyeing starts with the gray cloth passing through several stages of treatment before it becomes colorful and ready to wear. During this entire treatment only natural processes are used. Fabric and yarns used are certified organic cotton, natural cotton, silk, wool, linen, jute, hemp, etc. and their natural blends.

8.3 Desizing The washing of processed greige cloth starts with removing sizing, gums and oils used in the course of weaving by washing with natural mineral-rich water and sea salts.

8.4 Bleaching Fabrics are exposed to direct sunlight, use of a natural grass base and animal manure starts the bleaching process.



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8.5 Mordanting To make the colors bright and fast, natural mordants (an element which aids the chemical reaction so that the fibre absorbs the dye, preventing the colour from either fading with exposure to light or washing out) such as Myrballams, rhubarb leaves, oils, minerals, alum, iron Vat, etc., are used. No heavy metal mordants like copper, chrome, zinc, tin, etc., have been used.

8.6 Dyeing Herbal dyes or as in Wikipedia: “Natural dyes are dyes or colorants derived from plants, invertebrates, or minerals. The majority of natural dyes are vegetable dyes from plant sources – roots, berries, bark, leaves, and wood – and other organic sources such as fungi and lichens.” These have considerate advantage over conventional dyes, where various 8000 chemicals are known to be used in textiles industry for getting today’s vibrant colors. Turmeric is a great example of a natural dye used in Asia for many years, and it is a fantastic herb to treat small cuts and wounds. It is actually an antiseptic and anti-inflammatory herb, which means that you can stick it right into your first-aid kit. Turmeric is an ideal dye for fabrics that touch the skin of people, especially those allergic to fabrics dyed conventionally and infused with chemicals. Medicinally rich herbal formulations using plant material, minerals and oils like, turmeric, Myraballm, castor oil, sea salt, etc., are used for dyeing of the fabric or yarn. The medicinal qualities of the herbs are retained by immersing the plant material directly in the dye bath. The cloth does not lose its medicinal effect even after constant use since the medical dyes (herbs) go into the yarn itself. The yarn is dipped into the herbs and the fabric is dipped again.

8.7 Finishing In herbal dyeing, finishing is done by sprinkling pure water on the cloth and then stretching under pressure, using hand rolls, aloe vera, castor oil etc. With advent of new technologies, the growing needs of the consumer in the wake of health and hygiene can be fulfilled without compromising the issues related to safety, human health and environment. Taping new potential antimicrobial substances, such as, Chitosan from nature can considerably minimise the undesirable activities of the antimicrobial products.

8.8

Recycling plant

Solid and liquid waste is separated through the process of filtration and used for farming purposes as manure and watering the fields.

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8.9

Major differences between various dyes

Commercial dyeing

Eco-friendly dyeing

Vegetable dyeing

Organic dyeing

Herbal dyeing

Since when

Developed 80 years ago

Developed 10–15 years ago

Developed 60 years ago

Developed 500 years ago. Time tested

Pollution

Leads to heavy pollution. Uses 8000 chemicals

Pollution under check, but still uses 8000 chemicals

Cheap synthetic chemicals and dyes are still used

No pollution whatsoever as colors are from herbs, flowers, stems and roots

Allergies

Mostly allergic, pro-microbial inflammatory and bad for respiration

Could be allergic, pro-microbial inflammatory and bad for respiration

Depends on The herbs used chemicals used cure allergies and have antimicrobial, antiinflammatory properties

Cancer

42 cancercausing chemicals could be present

Only 22 cancercausing amines are eliminated

Depends on No chemicals used carcinogenic amines present

Fabric quality

The fabric used may be synthetic or natural

The fabric used may be synthetic or natural

The fabric used may be synthetic if chemicals are used

The process is possible only on natural fibres, e.g. wool, cotton

Chlorine bleach

Chlorine bleach is used

Hydrogen peroxide is used

Mostly chlorine bleach is used

Only natural/ manure bleaching

Detergents

Mostly nonbiodegradable detergents are used

Mostly degradable detergents are used

Could be nonbiodegradable or biodegradable detergents

No detergents are used

Textile strength

Weakens the fibres as strong chemicals are used

Weakens the fibres as strong chemicals are used

Depends on Strengthens chemicals used the fibres and ensures longterm life Contd...



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Contd...

Commercial dyeing

Eco-friendly dyeing

Vegetable dyeing

Organic dyeing

Herbal dyeing

Ecological

Even if organic textile base, lots of lethal chemicals are used, so not 100% pure

Incomplete ecological textile cycle even if organic textile due lots of harmful chemicals in processing

Incomplete even if combined with organic textile base because in some stages chemicals are used

100% pure – organic textile base along with natural herbal dyeing completes the ecological cycle

Carbon credits

Low opportunity for earning carbon credits

Low opportunity for earning carbon credits

Low opportunity for earning carbon credits

Immense scope for earning carbon credits through clean development mechanism scheme

Carbon footprints

Large carbon footprint

Large carbon footprint

Large carbon footprint

Almost zero carbon footprint

8.10

Major herbal dyes available

Herb

Latin name

Description

Madder

Rubia Tinctorun

Madder’s leafy tops sprawl untidily over the ground and their clusters of yellow-green glowers are insignificant. Yet to the dyer, madder is a miracle of colour because its roots contain alizarin, one of the most valuable red dye pigments ever known

Harikaki

Terminilia Chebulla

Haritaki is so named because it grows in the abode of Hara (Himalayas); it is green (harita) natural colour and it cures (harayet) all diseases.

Cutch, Cutechu

Acacia Catechu

The dye stuff known as Cutch or Cutechu is an extract usually made from the heat wood of Acacia Catechu, a small thorny tree. It yields orange-brown dyes that are rich in tannins, and was used in India calico printing before its introduction to West. It is used mainly to dye cotton and silk. Contd...

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Contd...

Herb

Latin name

Description

Indigo

Indigofera Species

Indigo’s ability to produce and extensive range of beautiful blue shades has made it the most successful dye plant ever known. The commercially available indigo powder is made from the leaves of Indigofera tinctoria, which requires hot, sunny and humid conditions to flourish

Turmeric

Carcuma Longa

Turmeric belongs to the family as ginger. Sometimes also known as Indian Saffron. It is the source of the familiar yellow colour of many Asian Curry dishes. Both the culinary spice and the dye are obtained from its roots. Turmeric was and still is used as textile painting and printing in India.

Onion

Allium Cepa

The outer skin of this common vegetable is one of the most useful and readily available dyestuffs. It is ideal for the novice dyer’s first experiments since it reliable produced rich vibrant shade of yellow, orange, rust and brown on all fibres and does not impart any odour to the dyed material.

Pomegranate

Punica Granatum

The edible pomegranate fruit yields ocher-yellow dye and the skins are rich in tannin, which improves color fastness. The pomegranate dye lacks brilliance so it is often mixed with turmeric root to make the color brighter. In India and Southeast Asia, it is used as a mordant and dye.

9 Carbon footprint in textile industry

9.1 Introduction The term ‘carbon footprint’ has emerged the latest environment terminology to be used frequently in the media. Whether you are environmentally challenged or environmentally savvy, chances are you would probably not be aware that unlike footprints of a more mundane variety a carbon footprint is rather weighty stuff. For instance, the ‘carbon footprint’ of that fancy T-shirt you are wearing is estimated to be around 6 kg i.e. around 20 times its own weight! But what exactly is ‘carbon footprint’? Carbon footprint is a measure of the severity of the impact our activities have on the environment, and particularly on climate change. It measures the impact by the amount of greenhouse emissions, produced through the burning of fossil fuels for electricity, heating, etc., in our everyday lives. Activities that have a large carbon footprint produce large amounts of greenhouse gases and therefore have a large impact on the environment.

9.2

Greenhouse gases and global warming

As greenhouse gases produced by human activities accumulate and their concentration increases in the atmosphere, this causes global warming. The main contributor to global warming is carbon dioxide, which accounts for nearly 80 per cent of emissions from the industrialised countries. The gas is released from burning of fossil fuels: oil, petrol and natural gas. With the rising population and increasing demands on transport and energy, the rate at which carbon dioxide is being released is also accelerating. Other greenhouse gases that originate from industrial and agricultural processes are: • Methane • Nitrous oxide • Hydrofluorocarbons (HFCs) • Perfluorocarbons (PFCs) • Sulphur hexafluoride (SF6)

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As these gases accumulate, they absorb infrared radiation in the atmosphere, thus changing the dynamic balance between the energy received from the sun and the energy escaping. The net result of these changes is a rise in temperature. Climate models predict a global temperature rise in the range of 1.4–5.80°C by the year 2100 if current warming trends continue unchecked. This is expected to trigger catastrophic events including: • Flooding of low lying coastal areas • Seasonal changes in the Northern hemisphere with wetter, warmer winters and hotter dryer summers • Worldwide extreme weather conditions with frequent storms, drought and heavy rainfall

9.3

Global warming and the textile industry

Everything that we do has a direct or indirect impact on the environment, because all our activities right from commuting to work to flying on a vacation involves burning fossil fuels that causes the production of green house gases. The impact of our activities is not limited to commuting but extends to everything we consume right down to the food we eat and the clothes we wear. In fact, the modern textile industry is one of the biggest sources of greenhouse gases, given the myriad processes and products that go into the making of any item of clothing.

9.4

Primary and secondary footprint

Human activity impacts the environment in two ways – directly through processes that burn fossil fuels and indirectly through the products that we use. The carbon footprint is therefore made up of the sum of two parts: the primary footprint and the secondary footprint. The primary footprint is a measure of the direct emissions of carbon dioxide from fossil fuels we burn including domestic energy consumption and transportation (e.g. car and plane). We have direct control over these emissions. The secondary footprint is a measure of the indirect carbon dioxide emissions over the entire lifecycle of the products we use – emissions associated with their manufacture and eventual breakdown. Simply put – the more we buy the more emissions will be caused on our behalf. The primary footprint of your commute to the office and back is pretty straightforward to calculate or estimate, but the secondary footprint concept is a little more involved and tricky. To understand the concept, you need to



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understand what is meant by the lifecycle of a product. The lifecycle of a product spans the entire period from the time the raw materials are farmed, produced, etc., to the time the product is finally disposed. If that is not complicated enough, there is no universally accepted way to measure the carbon footprint. For example retailers in the United Kingdom might only consider the emissions in the UK distribution of the T-shirt, accounting for only part of the supply chain. But if the entire process from cotton growing and mass production in India and delivery to UK retailers is considered the footprint would rise significantly. But that is not all, research has shown that the size of your T-shirt’s carbon footprint also depends on how frequently it is washed, and the manner in which it is washed and dried. Over the lifecycle, around 75 per cent of the T-shirt’s carbon footprint will be caused by machine washing and drying. However, if you dry the T-shirt on a clothesline instead of frequently tumble drying it, the figure falls significantly.

9.5

Carbon footprint and the textile industry

According to estimates, textiles and clothing typically account for around 4 per cent of the secondary carbon foot print of an individual in the developed world. Thanks to a number of factors including the growing awareness of environmental concerns, and perhaps more importantly, the benefits the textiles industry hopes to reap from reducing its carbon footprint, the industry has taken several initiatives in the direction of reducing its carbon footprint. If the textile industry is now seeking to align more closely with the goals of reducing its carbon foot print, it is because of a growing realisation that a smaller carbon foot print is not only environment-friendly but also makes good business sense on a number of counts. • For starters there is the low-cost – a low carbon foot print means lower consumption of energy which often means more efficient use of energy. Low carbon foot print processes cut costs by reducing waste of raw materials and energy. • Many companies have read the writing on the wall – the future is green and tough environmental regulation will be a part and parcel of the new green paradigm. Not taking the right measures now could jeopardize operations a few years down the line. Instead of running the risk of supply chain disruptions at a future date are increasingly aligning with the green concerns and environmental regulations. • Another important factor in the switch to greener alternatives is consumer pressure and demand. Informed consumers are now

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demanding products that comply with environmental regulations; and in an age of growing competition and consumer assertiveness, it is the consumer who drives sales and profitability. Which company can today afford to deny the consumer what he demands?

9.6

Strategies for reducing carbon footprint

Spurred by these factors, the textile industry and players across the value chain have adopted various strategies for reducing the carbon footprint. Besides the textile industry’s switch to more energy efficient processes, companies across the supply chain have also pitched in with innovative products with smaller carbon footprints. DuPont, the US-based chemicals major, which revolutionised the fibre industry with the introduction of man-made fibres like nylon, rayon and spandex now offers Sorona, a polymer which is made with agricultural feedstock instead of petrochemicals. Sorona has high renewable ingredients content – 37 per cent by weight. Fabrics made with Sorona provide a 30 per cent carbon dioxide reduction, while the Sorona manufacturing process reduces greenhouse gas emissions by 63 per cent as compared to conventional nylon made from petroleum. BASF, the German chemicals major, has launched a number of ecoefficient solutions that are environment-friendly and contribute to saving resources. Two of these were compared against the conventional systems used in textile mills: BASF’s after-soaping agent Cyclanon XC-W for dyeing and BASF Color Fast Finish system that is an intelligent colouration system. The former can reduce the processing time and water consumption compared to the conventional system. BASF Color Fast Finish, an intelligent coloration system, is a one-step process of textile dyeing and finishing, combining the dyeing, washing and finishing steps into one step, which can reduce the processing time and carbon dioxide emissions. Novozymes, Denmark, the world’s largest producer of industrial enzymes, which are basically proteins, has developed products for textile applications. These enzymes replace harsh chemicals used to remove impurities from the fibre or fabric which reduces energy costs, water consumption and also improves the feel of the fabric. Vijayeswari Textiles, Coimbatore, which switched over from chemicals to enzymes reports good results following with the replacement. Says R. Parameswaran, General Manager, ‘’We started using enzymes which have given us good results compared to the feel of the fabric, and also the output of the effluent.’’



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US-based Gaston Systems has developed an innovative machine that applies finishes to fabrics using foam, which conserves water. Huntsman, a Swiss company, is a leading supplier of dyes. The company has developed inks from the dyes which can be used in a digital printer for printing on fabrics just like the inks in an office printer. Digital printing wastes neither fabric nor ink and does not use harmful salts and significantly reduces the environmental footprint.

9.7

Revolutionary dyeing technologies

Conventional dyeing uses water to transport the fabric through the machine, a new technique uses air which significantly reduces water consumption. With conventional dyeing methods it takes 200 litres of water to make a T-shirt. With the revolutionary air technology, the same T-shirt can be made using 50 litres of water, which also reduces energy and chemicals consumption. Innovative denim mill: Lucky Textiles in China has recently built a new denim facility, the size of 11 football fields. Designed with the environment in mind, the facility uses natural light to serve most of its illumination needs. Thanks to the hi-tech systems it uses, Lucky can accurately use fewer chemicals and dyestuffs with absolutely no waste. With less chemical on the fabric, washing can be light which reduces the impact on the state-of-the-art water treatment. The company even built a new canal for the facility with connection to the Environment Protection Bureau which can monitor the quality of the waste water in real time. The global textile industry has taken several strides towards reducing its carbon footprint and meeting the challenges of building a more sustainable future. At the same time, there is a growing awareness of environmental issues among consumers who are now increasingly insisting on textile products complying with environmental standards. These complementary trends will hopefully continue to drive the industry toward offering the consumer products that are not only red, blue, white, etc., but also green.

9.8

Indian textile industry oblivious

The Indian textile industry however seems to be oblivious to the writing on the wall. At a 2-day national seminar organized by the Institution of Engineers (India), Shahi Group, Lakvinsar Projects and Infrastructure, held in Bangalore in February 2008, GS Nadiger, director (laboratories) textiles committee, in the ministry of textiles said that a large number of textile industries and units, particularly those in the processing sector across the country have failed to meet many environmental laws and regulations. He added that despite

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stringent environmental laws and regulations, the compliance level by the textile industry has not been very satisfactory. In November 2008, addressing an international conference, ‘Sustainability of Textile Fashion Industry Chain: Crop to Shop’, in New Delhi, minister of state for textiles, EKVS Elangovan called upon the industry to use cost-effective and energy-efficient technologies for encouraging sustainable development. He added that the industry’s size and extensive use of raw materials and chemicals makes it mandatory for the industry to adopt technologies that are environmentally sustainable. Speaking on the occasion, chairman of the Apparel Export Promotion Council (AEPC), Rakesh Vaid said that the industry needed to proactively work towards evolving a sustainable supply chain. He added that cotton waste recycling, low-carbon manufacturing programmes and carbon accounting in factories, carbon footprint calculation projects, benchmarking energy consumption across the textile and apparel supply chain are some issues that need to be addressed on a private–partnership mode. Mr. Vaid said that production strategies have not addressed sustainable production systems or alternatives so far. However, an important initiative was taken when on the sidelines of the conference, the AEPC joined hands with a global industry group led by retail major Marks&Spencer and the University of Leeds under a programme called ‘Reducing the Impact of Textiles on Environment (RITE)’. Under the programme, Pearl Academy of Fashion (PAF) which organised the conference will set up a joint apparel and garment coordination committee for sustainability. PAF intends to prepare a manual of best practice for sustainability for the fashion value chain. According to AKG Nair group director at PAF, the initiative is a significant step as India is a developing country with an aspiring consumption drive and vast untapped markets, but seems to be largely unaware of the emerging sensitivities related to sustainability. The Indian textile industry will need to cover a lot of ground on crucial environmental issues that will impact both competitiveness and bottom line in a regime driven by environmental and sustainability concerns. A world-wide paradigm shift towards cleaner and greener processes is already underway and it can no longer afford to remain a mute spectator if wants to emerge as a significant player in the globalised market. Although most of the current focus on lightening our carbon footprint revolves around transportation and heating issues, the modest little fabric all around you turns out to be from an industry with a gigantic carbon footprint. The textile industry is huge, and it is a huge producer of greenhouse gasses. Today’s textile industry is one of the largest sources of greenhouse



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gasses (GHGs) on earth, due to its huge size. In 2008, annual global textile production was estimated at 60 billion kilograms of fabric. The estimated energy and water needed to produce that amount of fabric boggles the mind: • 1,074 billion kWh of electricity or 132 million metric tons of coal and • between 6 and 9 trillion litres of water Fabrics are the elephant in the room. They’re all around us but no one is thinking about them. We simply overlook fabrics, may be because they are almost always used as a component in a final product that seems rather innocuous: sheets, blankets, sofa curtains, and of course clothing. Textiles, including clothing, accounted for about 1 ton of the 19.8 tons of total CO2 emissions produced by each person in the US in 2006. By contrast, a person in Haiti produced a total of only 0.21 tons of total carbon emissions in 2006. How do you evaluate the carbon footprint in any fabric? Look at the ‘embodied energy’ in the fabric – that is, all of the energy used at each step of the process needed to create that fabric. To estimate the embodied energy in any fabric, it’s necessary to add the energy required in two separate fabric production steps: 1. Find out what the fabric is made from, because the type of fibre tells you a lot about the energy needed to make the fibres used in the yarn. The carbon footprint of various fibres varies a lot, so start with the energy required to produce the fibre. 2. Next, add the energy used to weave those yarns into fabric. Once any material becomes a “yarn” or “filament”, the amount of energy and conversion process to weave that yarn into a textile is pretty consistent, whether the yarn is wool, cotton, nylon or polyester. Let’s look at #1 first: the energy needed to make the fibres and create the yarn. For ease of comparison we’ll divide the fibre types into “natural” (from plants, animals and less commonly, minerals) and “synthetic” (manmade). For natural fibres, you must look at field preparation, planting and field operations (mechanized irrigation, weed control, pest control and fertilizers (manure vs. synthetic chemicals)), harvesting and yields. Synthetic fertilizer use is a major component of the high cost of conventional agriculture: making just 1 ton of nitrogen fertilizer emits nearly 7 tons of CO2 equivalent greenhouse gases. For synthetics, a crucial fact is that the fibres are made from fossil fuels. Very high amounts of energy are used in extracting the oil from the ground as well as in the production of the polymers. Acrylic is 30% more energy intensive in its production than polyester and nylon is even higher than that. Not only the quantity of GHG emissions is of concern regarding synthetics, so too are the kinds of gasses produced during production of synthetic fibres. Nylon, for example, creates emissions of N2O, which is 300 times more damaging than CO2 and which, because of its long life (120 years) can reach

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the upper atmosphere and deplete the layer of stratospheric ozone, which is an important filter of UV radiation. In fact, during the 1990s, N2O emissions from a single nylon plant in the United Kingdom were thought to have a global warming impact equivalent to more than 3% of the UK’s entire CO2 emissions. A study done for the New Zealand Merino Wool Association shows how much less total energy is required for the production of natural fibres than synthetics: And next let’s look at #2, the energy needed to weave those yarns into fabric. There is no dramatic difference in the amount of energy needed to weave fibres into fabric depending on fibre type. The processing is generally the same whether the fibre is nylon, cotton, hemp, wool or polyester: thermal energy required per meter of cloth is 4,500–5,500 kcal and electrical energy required per meter of cloth is 0.45–0.55 kWh. This translates into huge quantities of fossil fuels – both to create energy directly needed to power the mills, produce heat and steam, and power air conditioners, as well as indirectly to create the many chemicals used in production. In addition, the textile industry has one of the lowest efficiencies in energy utilization because it is largely antiquated. But there is an additional dimension to consider during processing: environmental pollution. Conventional textile processing is highly polluting: • Up to 2000 chemicals are used in textile processing, many of them known to be harmful to human (and animal) health. Some of these chemicals evaporate, some are dissolved in treatment water which is discharged to our environment, and some are residual in the fabric, to be brought into our homes (where, with use, tiny bits abrade and you ingest or otherwise breathe them in). A whole list of the most commonly used chemicals in fabric production are linked to human health problems that vary from annoying to profound. • The application of these chemicals uses copious amounts of water. In fact, the textile industry is the #1 industrial polluter of fresh water on the planet. These wastewaters are discharged (largely untreated) into our groundwater with a high pH and temperature as well as chemical load.

10 New technologies and in textile dyeing and finishing

10.1 Introduction Green production has become necessary for enterprises under the upgrade and transformation policy. There are new perspectives on industrial upgrade by promoting new technologies which are both energy saving and waste reducing. As part of the Cleaner Production Partnership Programme, different upcoming technologies aim at helping enterprises achieve green production and cost reduction at the same time. The industry is desperately in the need of newer and very efficient dyeing/ finishing and functional treatments of textiles. There is growing awareness and readiness to adapt new perspective on industrial upgradation of Cleaner Production Programme, such new technologies help enterprises achieve green production and cost reduction at the same time. Green production has become necessary for enterprises under the upgrade and transformation policy. Therefore there is an urgent need to promote new technologies in textile dyeing and finishing, injecting new thoughts to the industry. Quality, economic efficiency and more and more ecological methods are the prerequisites for up-to-date production in the dye house. Color shade and depth must be attainable, and there should be adequate levelness and accurate fastness properties. Appropriate mechanical and chemical processing is necessary to suit customer requirements as well as to create the required fabric hand and surface characteristics. Economical and ecological efficiency involves minimization of costs and maximum profit as well as reproducible quality with minimal environmental damage. Therefore, process optimization is a must to fulfil all parameters and requirements for right-first-time production. Western wet-finishing costs are more and more apparent in various Asian countries as well, and can be divided into the following approximate cost proportions: • 42 percent labour; • 29 percent dyestuffs and chemicals; • 6 percent water; • 12 percent energy;

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• 6 percent environment and safety measures; and • 5 percent maintenance

10.2 Requirements The catalogue of modern, up-to-date dyestuffs and dyeing and finishing equipment offers a blend of modern technology and chemistry. Major requirements are as follows: • Reduced water consumption; • Varying load capacity; • Time savings; • Comparable economy and ecology; • Highly optimized rinsing processes; • Controller units; • Downstream processing advantages; • Wet finishing process; • Economical finishing; and • Monitoring and controlling

10.3

Electrochemical process technology

Electrochemistry refers to the use of electrical energy in initiating chemical reactions, replacing traditional aid agents in direct chemical reactions. Taking sulphur dyes as example, in traditional technology, sulphides (such as sodium sulphide, Na2S) are used as reducing agents. Although reduction process is fast and direct, large amount of chemical energy is wasted and wastewater with high chemical oxygen demand (COD) value is produced, making longterm operation inefficient. If direct electrochemical reduction is adopted, no reducing agents are needed and the COD value of wastewater can be largely reduced, hence lowering the cost of wastewater treatment. Direct electrochemical reduction is undoubtedly more efficient than the traditional technology, and the underlying chemical principle is also simple. However, as the stability and oxidising/reducing power of different chemical substances are not the same, dyes may not be directly and effectively reduced by electrodes. Hence the scope of utilising direct electrochemical reduction is quite narrow. The principle of indirect electrochemical reduction is the same, but in operation another strong oxidising/reducing agent acts as medium, which makes the technology more applicable to different kinds of dyes. Taking indigo as example, traditional technology takes sodium dithionite (Na2S2O4) as a reducing agent, and the product should be re-oxidised in the air afterwards



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to fix the colour. Just like traditional reduction of sulphides, large amount of chemical energy is wasted and wastewater with high COD value is produced. The process houses attempt to reduce the amount of sodium dithionite used in order to lower production cost, but such attempt produces other difficulties as well. For example, injecting nitrogen can reduce the oxidation of sodium dithionite but is too expensive. Adding aldehydes or directly powering with electricity can improve the reducing power of sodium dithionite, but the problem of wastewater remains. If indirect electrochemical reduction is adopted, the medium can replace sodium dithionite as the reducing agent. The medium can provide both oxidising and reducing substances and can regenerate so that both waste and pollution can be reduced. Past experiments show that reduction by electrolysis can save about 90 per cent of production cost when compared with reduction by sodium dithionite. Apart from reducing dyes, electrochemical process technology can be utilised in other aspects. Taking bleaching as example, the core principle of electrochemical mercerising and bleaching is that bleaching chemicals can be produced by electrical energy and can be regenerated; hence the process is easily controlled, waste reducing and energy saving. The process can be monitored so that bleaching occurs evenly. Also, the cost and danger of transportation is greatly reduced, particularly regarding hydrogen peroxide which is explosive. Another emerging project is the technology of ozone electrolysis. Ozone is strongly oxidising and can be used in decolourising and other waterless dye treatments (e.g. ozone jets to prevent wearing out of jeans). As ozone can self decompose, it will not cause pollution problems once carefully treated.

10.4

Supercritical fluid dyeing technology

Supercritical fluid refers to the phase of a substance with both temperature and pressure higher than the critical point (the point where liquid and gaseous phases of a substance become indistinguishable). This phase of a substance enjoys many advantages and can replace water in the dyeing process. The supercritical fluid normally used is carbon dioxide (CO2), as the critical temperature and pressure are easier to achieve than that of other substances. Moreover, carbon dioxide is also non-flammable without residue, so it is suitable for industrial use. In traditional water-dyeing technology, textiles should undergo multiple processes with the help of aid agents, chemical salts, surfactants and reduction clearing agents. In contrast, for the supercritical waterless dyeing technology, only supercritical fluid is needed for dyeing and

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circulation, after which the pressure and temperature can be lowered and the whole process is finished, without producing any wastewater. Also, as carbon dioxide automatically detaches from textiles and remaining dyes, the latter can be reused. More importantly, as operation procedures are reduced, the dyeing cycle is also shortened from several hours to 15 to 60 minutes; energy is also saved due to the lower operational temperature. Regarding the cost, although the equipment required for the process is quite expensive, the super- critical substance (carbon dioxide) is cheap and the technology enjoys an overall advantage in cost. On the other hand, although the technology is not mature enough regarding application in natural fibres, the quality of the end product made of synthetic fibres is high. Overall, the effects of interactions between different textiles with supercritical substances are yet to be fully discovered. A Dutch company has unveiled what it believes to be the first commercial dyeing machine to replace water with supercritical carbon dioxide – a pressurized form of the gas with unusual liquid-like properties. Heated up to 31°Celsius (88 degrees Fahrenheit) and pressurized to 74 bar, CO2 takes on the characteristics of both a liquid and a gas, allowing for the dissolution of compounds such as dyes. For DyeCoo Textile System’s purposes, scCO2 is heated to 120°Celsius (248 degrees Fahrenheit) and pressurized to 250 bar. Behaving as both a solvent and a solute, the supercharged carbon dioxide penetrates textile fibres and disperses the preloaded dyes without extra chemical agents. Once the dyeing cycle is complete, the CO2 is gasified to recover the excess dye. Unburdened, the clean CO2 cycles back into the dyeing vessel for reuse, a manoeuvre that saves energy, water, and the heavy metals that comprise much of the toxic runoff into our planet’s polluted waterways, according to DyeCoo. The process isn’t without its limitations, however. DyeCoo is currently only able to dye scoured (or prewashed) polyester fabric, although the company notes that it’s working on a version that will dye unscoured fabric, as well as reactive dyes for cellulosic textiles made from plants.

10.5

Plasma treatment technology

When a substance in its gaseous phase absorbs enough energy, the outermost electrons in the atoms will escape (including textiles), leading to various chemical fusions and fissions. These effects can alter the surface structure of textiles; hence plasma is suitable for surface treatment. Since only the surface structure of materials is altered by plasma, the substrate characteristics of textiles will not be affected. Also, as small amount of plasma is enough to produce profound effect and one set of equipment can accommodate to



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different kinds of gaseous chemicals, the equipment is relatively cost effective and user friendly. The kinds of plasma undergoing testing are varied, including silanes (SinH2n+2) (waterproof ), freons (increasing surface tension and oil- and dirt-proof effects) and phosphorus containing organic monomers (fireproof), etc. Plasma treatment technology can also improve existing dyeing technology, including the newly developed technology of metallised fabrics. On the other hand, textile technologist attempts to integrate plasma treatment technology and supercritical fluid dyeing technology, and replace supercritical fluid with plasma in the dyeing process. The low pressure plasma dyeing technology is still being developed. The textile dyeing and finishing industry is considered energy-wasting and highly-polluting, which will be forced to withdraw under the upgrade and transformation policy. However, with technological development on a full swing, traditional industries are able to overcome technical difficulties and revive after the financial crisis.

10.6

AirDye technology

It manages the application of color to textiles without the use of water. It was developed and patented by Colorep, a California-based sustainable technology company. The process of making textiles can require several dozen gallons of water for each pound of clothing. The AirDye process employs air instead of water to help the dyes penetrate fibres, a process that uses no water and requires less energy than traditional methods of dyeing. The technology works only on synthetic materials and is currently available only in the United States. Colorep says it plans to extend its use to Europe by the end of summer, and to Central America by late this year. The AirDye process employs air instead of water to help the dye penetrate the fibre. AirDye technology heats up fabric, then injects dye directly into the fibres in the form of a gas. The AirDye process uses no water and less energy than traditional methods, while still achieving impressive colors in solids and prints. Airdye is a proprietary technology that cannot be done in the traditional sublimation or heat transfer process. Paper, which can be recycled, continues to be the medium for transferring disperse dyes to fabric. AirDye technology works only on synthetic materials. It can be used to dye clothes, swimwear, carpet, curtains, linens, event banners, and ceiling tile. AirDye technology manages the application of color to textile without the use of water, providing a sustainable alternative to traditional cationic or vat dyeing processes. The process does not pollute water, greatly reduces energy use, lowers costs, and satisfies the strictest standards of global responsibility.

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Future developments will be directed by economics, but the environment also will be taken into account. Suitable after-treatments will be developed with the target of recycling dyeworks effluent, and other developments will be aimed at emissions reductions. There will be much movement in this area in the future.

11 Dyeing technologies for the future

11.1 Introduction Water scarcity and increased environmental awareness are worldwide concerns which are causing a sharp rise in prices for intake and disposal of water. The textile industry is also one of the biggest consumers of water with conventional textile dyeing using large amounts of fresh water which is disposed off as wastewater containing dyestuff chemicals. The Pollution Control Board in India has become also very strict. Tirupur Processing units are all closed. Bhilwara process units are also under terrible pressure maintaining the zero-discharge notification. Vapi, Ahmedabad, Kolkata, Jetpur, Pali, Surat, Bhiwandi are also under pressure to follow the strict norms. Most of the discussion in sustainable textiles has centered around the fibres – manufacturers making a switch to organic cotton, or creating fabrics from natural easily renewable materials like bamboo or hemp. But very little attention has been paid to the dyeing process, which can be a potentially devastating industry when it comes to chemicals, waste, and water usage. AirDye®, a new method created by Colorep for dyeing textiles takes water almost out of the equation, using 90% less water, but also reducing the emissions and energy used by 85%, since extreme heat is needed to dry the textiles after they are soaked in dye (and most fabrics then require a post-rinse and yet another dry cycle. About 4,000 years ago, man used water to carry dye to a piece of fabric. Early water pollution was born. Since then, more and more chemicals have been added to color fabric, producing ongoing and ever worsening water pollution. In the mid 20th century, came new fibers such as nylon and polyester. These new “high tech” fibers were difficult to dye so heavy metals and other toxic compounds were added to water baths to carry the dyes. These toxins end up in the world’s lakes, rivers, and oceans causing horrific damage. Today the World Bank estimates that 17–20% of industrial pollution comes from textile coloring and treatment. They’ve also identified 72 toxic chemicals in our water solely from textile dyeing, 30 of which are permanent.

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From experience, it is known that an estimated 100–150 litres of water are needed to process 1 kg of textile material. Water is also used as a solvent in many pre-treatment and finishing processes, such as washing, scouring, bleaching, dyeing, rinsing and finishing and the contaminated water must then be handled and treated prior to disposal or recycling. There is going to be very huge water scarcity as compared to population growth. After dyeing the disposal of the effluent is also a great problem.

11.2

Options to overcome the environmental problems in the future

11.2.1

Salt-free dyeing of cotton fabrics

Textile scientists have developed a more efficient method of dyeing cotton that is not only less harmful to the environment, but also uses significantly smaller amounts of energy, water and salt in the dyeing process. The key to the new process, called cationic fiber modification, is treating the cotton with a chemical that gives it a positive charge that attracts negatively charged dyes. “The new process is much more efficient and saves about half of the time normally required to dye cotton. It uses one-third of the energy and only 20 percent of the water used in traditional methods, and no salt.” Traditionally, cotton is dyed using water-soluble dyes, but these compounds don’t naturally adhere well to cotton, so large amounts of salt must also be added to the mix to make the dye less soluble and better at adhering. The amount of salt needed sometimes approaches ratios of 1-to-1 by weight of the fabric. Large amounts of water are also needed; it takes eight gallons of water to dye one pound of fabric. In cationic fiber modification, a chemical called N-(3-chloro-2hydroxypropyl) trimethylammonium chloride is applied to the cotton before it is dyed. The chemical gives the cotton fiber a permanent positive electrical charge, which strongly attracts the negatively charged dyes. All cotton dyes have negative electrical charges. As a result of the electrical attraction, less dye is needed. The colors in the fabric appear to be more vivid. There is no noticeable change in the texture of the cotton fiber. Another benefit of the new process is that it can be done using standard dyeing and finishing machines, so manufacturers don’t have to retool their operations. Textile scientists are now focusing their research on how to streamline the new process even further. Currently, they say, one drawback is that the



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fabric has to be taken out of the manufacturing line to have the chemical applied. Then it must be given time to react with the chemical. This extra step significantly slows the process of dyeing and finishing, which are best completed as one uninterrupted process. They are working to overcome that problem, but the biggest hurdle may be convincing industry to embrace the new process. “The textile industry is very slow to adopt change, (especially on) something like this that mainly reduces pollution and energy consumption. There’s been some interest in this, but so far commercialization has been slow.” “This is going to be driven by the people who need to reduce pollution from their plant, or want to save energy or double their production capacity without buying more equipment.” Dow Chemical Co. is the manufacturer of the chemical that gives the cotton a positive charge.

11.2.2

Waterless dyeing process

The Yeh Group was established in 1988 and is located on a 40 acre site near to the city of Bangkok in Thailand, where it specializes in performance polyester knit fabrics. The group is composed of Tong Siang and Penn Asia and has sales offices located in Europe and North America. Current customers include Adidas, The North Face, Puma, Mammut, Odlo, Mizuno and Victoria Secret. DyeCoo Textile Systems B.V. is based in the Netherlands and claims to be the world’s first supplier of industrial CO2 dyeing equipment, for which it holds patents. It produces both warp and weft knitted fabrics, says it will be the first textile manufacturer to implement a new waterless dyeing process developed by DyeCoo Textile Systems of the Netherlands which is currently being readied for commercial introduction in the fourth quarter of this year. Elimination of process water and chemicals are a real breakthrough for the textile dyeing industry. DyeCoo Textile Systems designs and manufactures machines using carbon dioxide (CO2) for dyeing of textile materials. It’s a complete water-free dyeing process with considerable lower operational costs compared to the conventional dyeing processes. Advantages: • Elimination of water consumption • Elimination of wastewater discharges • Wastewater treatment process eliminated • Elimination of drying and dryer effluent • Reduction in energy consumption • Reduction in air emissions • Reduction in dyeing time • Surfactants and auxiliary chemicals in dyes eliminated

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• Dye utilization is very high with very little residue dye. Unused dye can be recaptured • Approximately 95% of used CO2 will be recycled • Fewer redyes are required • Color correction is easier compared to aqueous dyeing. The company says it has exclusive rights to the process and is branding fabrics produced using it as DryDye fabrics.  Supercritical fluid CO2

“Elimination of the water process and chemicals is a real and significant breakthrough for the textile dyeing industry. This new process utilizes supercritical fluid carbon dioxide (CO2) for dyeing textile materials. It is a completely waterless dyeing process using only nominal amounts of CO2, nearly all of which is recycled. DryDye fabrics dyed with this unique waterless process will have the same dye qualities and durability as current, conventionally dyed fabrics,” a spokesperson for the Yeh Group said. The Yeh Group, which claims to be an innovative, environmentally responsible producer of quality knit fabrics and garments, supplies to premium brands in sports and intimate apparel markets. By pioneering and implementing this new waterless dyeing process, the company says it will eliminate the use of millions of litres of fresh water in dyeing fabrics using the new process. Instead of current aqueous dyeing systems, DryDye fabrics will be dyed using supercritical carbon dioxide in a stainless steel chamber developed and tested by DyeCoo. Yeh Group says, for the past three decades, supercritical fluids have been used in various extraction processes, including the extraction of natural substances for the production of pharmaceuticals, cosmetics and spices. In addition, leading producers of textiles dyestuffs have attempted to harness the technology for textiles dyeing but none has produced a successful commercial system to date. Supercritical fluid CO2 is said to have become a mainstay in extraction processes in the food industry (decaffeination, extraction of hops) and apparel dry cleaning, where it is said to be the best, gentlest, most thorough cleaning method now available. Carbon dioxide is also said to be considered the best supercritical fluid for the dyeing process, is naturally occurring, chemically inert, physiologically compatible, relatively inexpensive and readily available.  Dyeing polyester and other synthetics

“Using supercritical fluid CO2, polyester and other synthetics can be dyed with modified disperse dyes. The supercritical fluid CO2 causes the polymer fibre to swell allowing the disperse dye to easily diffuse within the polymer,



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penetrating the pore and capillary structure of the fibres. The viscosity of the dye solution is lower, making the circulation of the dye solutions easier and less energy intensive. This deep penetration provides effective colouration of polymers which are characteristically hydrophobic. Dyeing and removing excess dye are processes that are done in the same vessel. Residue dye is minimal and may be extracted and recycled,” the Yeh Group says. Reductions in operating costs

According to the Yeh Group, supercritical CO2 dyeing gives excellent results as far as dye levelness and shade development are concerned. The physical properties of dyed yarns are also said to be equivalent to conventional methods. Conventional textile dyeing is very water and energy intensive in pretreatment, dyeing, and post-treatment (drying). The supercritical CO2 process, however, is said to use less energy than conventional processes, resulting in a potential reduction in operating costs of up to 50%. The company says the only overlap is in the pre-treatment process, which is essentially the same for both.

11.3

AirDye technology

What’s more, traditional dyeing uses an astonishing amount of water. Estimates vary, but to color just one piece of fabric can take anywhere from 7 to 75 gallons of water per pound of fabric (26 to 284 liters per 0.45 kilo). So traditional dyeing pollutes badly, widely, and continues to consume vast amounts of the world’s increasingly scarce fresh water. Why air dye? The textile industry is the third largest consumer and polluter of the world’s water. The World Bank estimates that 17–20 percent of industrial pollution comes from textile coloring and treatment. About 72 of the toxic chemicals in our water come solely from textile dyeing – 30 of these cannot be removed, despite purification processes. AirDye technology prints and dyes without consuming water or emitting pollutants. Brilliant shades, beautiful prints. No harm done. AirDye® technology manages the application of color to textiles without the use of water. It is today›s sustainable alternative to traditional dyeing and printing processes. By using air instead of water to infuse color into fabric, the technology reduces water consumption and pollution. The innovative new process also creates additional opportunities to apply design and color in ways not previously possible. AirDye technology creates new design capabilities while reducing cost: AirDye technology from Colorep, Inc., a California-based sustainable technology company, is a solution our planet needs today and for many

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tomorrows. Business today must achieve high quality, lower costs, competitive practices, and meet customer demand for environmentally responsible products that are attractive.

11.3.1

How is AirDye different?

Conventional dyeing, such as vat dying or cationic dying, can produce good looking results. On the down side, they use polluting heavy metals, a huge amount of precious water and do not provide permanent coloration. Sublimation printing has been used to decorate textiles but is limited in application. AirDye advances both. AirDye’s process begins with using synthetic fibres for its material, which can be made from recycled PET bottles. Using disperse dyes that are applied to a paper carrier, AirDye uses heat to transfer the dyes from the paper to the surface of the textiles, coloring it at the molecular level. All paper used is recycled and dyes are inert, meaning that they can go back to their original state and can be reused. Developed in California by Colorep Inc, AirDye uses proprietary dyes, which are heat transferred from paper to fabric in one-step process. By bypassing the liquid stage of the dye process, between 7 and 75 gallons of water are saved in the dying of a single pound of fabric. The paper is recycled, as are the remaining dyes, which are turned into tar and asphalt. There are no harmful byproducts and a significant reduction in energy and cost as no screens, boilers, dryers or chemicals are needed. A wide range of synthetic fabrics from sheer chiffons to performance stretch can be used. Fabrics can be printed one-sided or reversible and feature complementary or contrasting sides of colour or print. Here are four microscopic photos of the neck section of a dyed synthetic T-shirt:



• Standard sublimation and heat transfer printing – The dye does not completely penetrate the fibers, therefore, white fiber may show after cutting or needle penetration.

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• Conventional dyes – After treatment in a water dye-bath, the fibers show complete dye penetration. However, colorfastness is low to moderate.



• AirDye controlled penetration – Using our proprietary Sibius™ dyes, penetration is deeper. Colors are richer and colorfastness is better. Penetration control is used with Dye Contrast, Print 2 Dye, and Print to Print products, including AirDye wovens.



• AirDye® complete penetration – AirDye is so advanced that it not only colors the yarn, but also thousands of filaments in each piece of yarn, yielding rich, brilliant colors. Penetration is complete.

11.3.2

Advantages of AirDye technology

• Does not pollute water in the color application process. By using air instead of water to convey dye, no hazardous waste is emitted and no water wasted.

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• Greatly reduces energy requirements, therefore lowering costs, and satisfying the strictest standards of global responsibility. • Does not use boilers, screen printing machines, drying ovens, or cleaning and scouring chemicals, thereby eliminating major sources of pollution. • Eliminates water in the color application step and simplifies the process, creating revolutionary possibilities of new industry and employment in unfarmable, arid regions of the world. • Gives consumers a way to choose style and sustainability at a realistic price at the point of purchase, thereby initiating world change. • Disperse dyes are used. It is suitable for polyester, nylon, and poly blends as well as certain hard plastics. • Is similar to transfer printing but more advanced both in the dye formulations and in the transfer methodology. • Is easy to specify, reduces cost, offers beauty and quality, and reduces environmental impact. • Offers style without sacrifice. There is no dye-lot variation, no post-dye washing or treatments, and no minimum quantity. • Offers exciting new options: – Dye different colors on opposite sides of fabric. – Dye fabric a solid color. – Dye one side a solid color and the opposite side a print. – Dye one side of fabric with a print and the opposite side with another print – Dye opposite sides of fabric with the same print. • Reduces water consumption by 95% • Reduces energy use by 86% • Reduces green house gas emissions by 84% In textile industry, more than 2.4 trillion gallons of water is consumed each year to dye synthetic textiles, and more than 2.8 trillion megajoules of energy, while emitting over 568 million metric tons of green house gases, to design textiles that can feature a look on the front surface of the fabric and different on the back. Fabrics can be printed with a different solid color on each side of the fabric, two different patterns on each side, or combinations of solid colors and patterns.

11.4 Conclusion AirDye technology produces superior results compared to sublimation printing and conventional dyeing, but that is just the beginning of its advantages. AirDye technology also reduces detrimental impacts on the environment. And because the dye is in the fiber rather than on the fiber, bleach and cleaning



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agents can’t get to it, so colors look richer and last longer. The result is more beautiful colors and maximum color durability, with substantially less water and discharged chemicals. The result is luxuriously brilliant color and a world-changing impact on our planet’s water shortage. Not a bad day’s work. AirDye technology is a proprietary process created by parent company Colorep Inc., based in California, USA. As a world innovator, Colorep is passionate about creating new printing and dyeing technologies that improve quality, value, and accessibility while helping to sustain the planet. The technology works only on synthetic materials and is currently available only in the United States (where only a small fraction of the world’s clothing is made, of course). One limitation: “It does not work on cotton or wool or the other fiber types. But Colorep says it plans to extend its use to Europe by the end of summer, and to Central America by late this year. By next year it will be launched in Surat market keeping an eye on the huge synthetic market.

12 Importance of blue sign in textile industry

12.1 Introduction The Blue Revolution bluesign® technologies promotes eco-compatibility throughout textile-processing supply chain. A new revolution is underway in industry, and it is starting in the textile and apparel sector. There is a difference, however, between this new revolution and the Industrial Revolution that began in the 18th century and completely transformed production processes. That earlier revolution also sped up the processes that have polluted the air and water, created toxic substances that threaten human health, caused climate changes and depleted natural resources. The new revolution aims to halt the progress of environmental degradation by using only those materials, technologies and processes that cause no harm to the environment and result in products that are safe in all aspects for consumption and use by humans.

12.2

Blue is for clean

The Industrial Revolution is often associated with the color black, suggesting coal, smoke, iron and black gold. The revolution taking place today often associated with the color green, which signifies the earth can also be linked to the color blue, which represents clean water and air, as well as purity in general. Switzerland-based bluesign® technologies AG, a new consortium dedicated to promoting and facilitating environmentally sustainable, toxinfree textile production, is currently involved in the research and development of new processes, technologies and components for the manufacture of apparel. Bluesign Technologies Ag was founded in Switzerland in 2000 with the intention of providing a comprehensive production control system to limit the human health and environmental impacts of textile manufacturing. It is now 80% owned by the international testing company SGS. Consumers looking for apparel guaranteed to be free of toxic substances and produced without causing environmental harm can look forward soon to a day when garment hang-tags will certify the eco-compatibility and safety of garments that conform to the new bluesign standard. At the same time, comfort, design and functionality



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levels of these new products will not be compromised. Since 1997, bluesign has been working in partnership with a number of textile and textile-related companies in efforts to develop and market new products. With regard to textiles, the consumer wants a simple and clear orientation system he can trust, states Dr. Cornelia Voss, nutritionist and head of the textile department, Wissenschaftsladen Bonn e.V. Zentrum fur burgernahen Wissenstransfer, Germany. Credible concepts for the greatest possible freedom from toxins, safety and transparency are also receiving the support of powerful consumer and environmental associations. Of course, the move to improve and clean up production processes and develop sustainable technologies and products has gained momentum in recent years, and, indeed, is mandated by certain government policies and laws. TI has reported on a number of other efforts to this end in the textile community including efforts in the carpet industry and Cargill Dow’s development of synthetic fibers using polylactic acid (PLA) from corn sugars. Among bluesign’s objectives is the creation of a network throughout the textile product supply chain of companies dedicated to using environmentally safe and responsible methods and materials at each step in the manufacturing process.

12.3

First products in the marketplace

The first products of bluesign’s venture, made from synthetic fibers, have recently been introduced to the marketplace. Switzerland-based Schoeller Textil, a company known for its innovative performance fabrics, has produced a line of polyester fabrics made entirely without the use of environmental toxins. This new production process lowers energy consumption by 85 percent and water consumption by 75 percent. The new production process for these fabrics requires less raw materials and eliminates toxic by-products, said Tom Weinbender, president, Schoeller Textil USA, Seattle, Wash. The quality of these cutting-edge fabrics is not compromised in any way, resulting in the same high standards that Schoeller customers expect. The bluesign standard is based on five principles of sustainability. These are resource productivity, consumer safety, air emission, water emission and occupational health & safety. Instead of testing a manufacturer’s finished product, the applied components and processes are already audited pre-production. This socalled Input Stream Management System ensures that the use of problematic substances is avoided from the start resulting in an entirely safe finished product. The bluesign standard defines specific criteria applied to each phase within the production chain to ensure compliance with the five principles

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of sustainability. These criteria are based on the concept of “Best Available Technology” (BAT). Fundamentally, they require a high level of safety both for human beings and the environment as well as a sustainable production process. There are three key tools in the bluesign concept: • bluetool – The chemical evaluation tool. Chemical products must be “homologated” with the bluetool to be bluesign approved • bluefinder – The database of approved dyes and chemicals from system partner suppliers (not in the public domain) • blueguide – A catalogue of producers of bluesign-approved textile products DyStar joined the bluesign platform as a system partner in 2008 and now has more than 600 textile dyes and pigment preparations and more than 200 textile auxiliaries listed in the bluefinder database so that manufacturers have the widest possible choice of quality products to choose from when they are seeking to produce bluesign approved fabric. The independent bluesign standard since 2000 to evaluate and reduce resource consumption and to screen raw materials, including dyes and finishes, is used in our supply chain. bluesign technologies, based in Switzerland, audits the energy, water and chemical usage of its system partners and helps them achieve continuous, long-term environmental improvement. Bluesign system partners agree at the outset to establish management systems for improving environmental performance in five key areas of the production process: resource productivity, consumer safety, water emissions, air emissions, and occupational health and safety. System partners regularly report their progress and must meet improvement goals to maintain their status; bluesign technologies performs regular audits. In addition, the bluesign standard helps factories implement an inputstream management system for raw materials. This includes screening of chemicals, which are assigned to one of three categories: blue, safe to use; gray, special handling required; and black, forbidden under the standard. The bluesign standard helps factories eliminate black chemicals and find equivalent alternatives. It’s a rigorous standard, but as of spring 2012, 16 percent of our products contain “bluesign-approved fabrics”. Our progress has inspired us to work with other suppliers in the outdoor industry to encourage more major textile providers to adopt the bluesign standard. We have established a goal with our suppliers to have all Patagonia fabrics bluesign-approved by 2015. With the global seal of approval for environment, health and production safety, the bluesign standard helps you and your suppliers to establish sustainable products without compromising functionality, quality and design.



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Increasing raw material prices, the need to protect the environment and the global shortage of resources such as water are some of the challenges faced by the textile industry. Being successful in the marketplace means that you need to take responsibility when it comes to environmental and consumer protection, which in turn means prioritizing your ecological footprint. The bluesign standard offers an independent approval system for the textile industry, taking into account the whole production process, minimizing the impact on the environment and safeguarding human health. It also helps to decrease your production costs, increase your competitiveness and innovation, benefiting your business. Consumers are increasingly aware, not only of their own impact on the environment, but also that of the products and businesses they use. As a result consumers are looking to your products to offer transparent value chains, high quality, harmless and environmentally safe credentials. Bluesign screening tackles the problem at its root. Instead of focusing on testing your finished product, it looks at all input streams – from raw materials, to chemical components, to water and energy resources. Every component is assessed, eliminating potentially harmful substances before you even begin production.

12.4

The principles of bluesign

The standard is built around five principles: • Resource productivity • Consumer safety • Air emissions • Water emissions • Occupational health and safety Resource productivity

Aims for maximum quality and added value for your product using minimum resources and the least possible environmental impact. Consumer safety

Consumer safety includes not only that your textiles need to be of high quality and without health risks, but also the assurance that you apply all the principles of sustainability during your production process. Air emissions

Air emissions need to comply with strictly controlled limits along your entire production chain. Using low emission components and optimizing energy use reduces your CO2 load.

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Water emission

Water emission control aims to feedback purified water into the natural cycle, causing the least possible pollution of rivers, lakes and seas. You can achieve this by using ecologically harmless components and by optimizing production and waste water treatment processes. Occupational health and safety

This involves the health and safety of your employees in the textile industry. It means that weak points that might exist locally can be detected and improved in line with regulations.

12.5

Three steps to achieving bluesign standard

12.5.1 Screening Screening is the first step to implementing the bluesign standard. Experts carry out a full bluesign screening of your company. This evaluation enables you to not only eliminate hazardous materials and other environmental risks, but also establishes the most economical use of your resources.

12.5.2 Implementation This stage involves resolving problems highlighted during screening. This stage is tailor-made to your business, offering you an individual implementation plan.

12.5.3

Certification

During this final stage of the process, we carry out tests and inspections so that your individual products and product groups can be certified. With the global seal of approval for environment, health and production safety, the bluesign standard helps you and your suppliers to establish environmental standards for textiles without compromising functionality, quality and design. Schoeller’s new line includes a variety of fabrics, from soft and drapable microfiber fleece knits to durable and rugged lightweight rip-stop weaves. In addition, the company owns Nano-Finish, which is developed using nanotechnology applications in accordance with the bluesign Standard, provides optional water- and soil-repellent attributes to the fabrics. Other development partners or licensees in the bluesign system include Acordis, Ciba, 3M, Ems-Chemie, Eschler, Gortz KG (Greenpeace products), KUAG, Nike, Prym, Rudolf Chemie, and Trevira. These partners are licensed by



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bluesign to use its technologies, and their production processes are monitored to ensure that the bluesign Standard will be maintained in products using the company’s name. In turn, bluesign reinvests the fees paid by these companies in new research. Licensees have access to bluesign’s entire body of knowledge; compatible components, processes and technologies; and engineering services. The products are marketed by the labeling of bluesign® brands, brand communication and distributor support. Leaders in science, environmental policy, industry, and environmental and consumer organizations are monitoring bluesign’s work. Research institutes associated with the system include ETH Zurich, Tex-a-Tec and oko-Institut Freiburg. In addition, bluesign is in a technology partnership with the Steilmann Group to develop new polyester textiles that comply with its standards.

12.6

What’s blue and what’s black

bluesign has placed products, substances and technologies into three categories, according to their degree of compliance with its standards. The bluesign standards exceed those set forth in oko-Tex Standard 100, the European standard established in 1992 for the environmentally responsible production of textiles. The bluelist includes products, substances and technologies that make the entire production chain as toxin-free as possible and demonstrate totally environment-compatible behavior from raw materials processing (including fiber and dyestuff manufacture) through fabric finishing and garment manufacture. The list also embraces consumption and disposal methods. It includes: single-sort materials that are easily reduced to their raw materials and are recyclable in raw-material form (e.g., polyester into terephthalic acid and glycol); innovative technologies, such as nanotechnology; the use of sustainable raw materials, such as cornstarch; catalyst systems that comply with the bluesign standards; disposal methods that allow biocompatible materials to break down aerobically or anaerobically; and disposal methods by which non-bio-compatible materials are mineralized into carbon dioxide and water, so that their residues are bio-compatible. Next in rank is the greylist of Best Available Technologies (BAT), comprising products and technologies that are the best currently available. They are being used in the interim, but they will be improved upon as better technologies become available, and once deemed eligible, they will be transferred to the bluelist. Last is the blacklist of hazardous substances and technologies. These items will never be used in the manufacture of bluesign-licensed products. The blacklist includes any substances that have potential carcinogenic, mutational or adverse reproductive effects; that accumulate in water or living organisms; or that have toxic or hormonal effects on living organisms. Included on this

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list are antimony, mercury compounds, polycyclic aromatic hydrocarbons (PAH), tributyl tin (TBT) and chlorine bleaching, among other items. 

12.7

Ecology and high-tech go hand-in-hand

Eco-efficiency is defined by bluesign as the relationship between the overall expenditure of nature and the specific benefit per project or service unit. As Peter Waeber, CEO, explains: ecology and high-tech are not opposites. On the contrary, we can only observe our responsibility to living and future generations by using the most modern technology. Ecological is no longer synonymous with hand-knit. We will be able to treat sustainable raw materials such as corn starch so that they display the functions of modern chemical fibers and can be returned to the natural cycle at the end of their useful lives. Another example of the ecology/ high-tech connection is the use of nanotechnology to develop new textile-finishing processes that can imbue fabrics with various properties, including dirt- and water-repellency, by changing the molecular structure of the fibers. Fabrics having dirt- and water-repellent properties behave in the same way as a lotus leaf, which repels dirt and water due to its rough, scale-like surface. The use of nanotechnology to create these properties in fabrics eliminates the need to use halogenated compounds to achieve the same effects. Driving home the importance of implementing eco-efficient practices is the fact that normal industrial production creates 30 tons of waste for every one ton of finished product. The products of nature are not necessarily excluded from bluesign’s efforts to develop new eco-friendly products, although the consortium is concentrating on improving production of synthetics because, in general, their manufacture generates more toxic pollution than the processing of natural fibers. The key to compliance with the bluesign Standard is the use of environmentally responsible cultivation, harvesting and processing methods. In the interest of eco-efficiency, the bluesign system is promoting the following goals and ideas: • Harvesting, processing and finishing of raw materials and products must all be accomplished in an intelligent, economical, environmentally safe (including toxin-free) manner • Intelligent solutions combine eco-efficiency with a high degree of functionality, design and quality; combine nature and technology; and use sustainable energies, such as solar and hydrogen energy. • The elimination of harmful materials and processes begins in the design stages of a product; hazardous substances and technologies are never even considered to be viable. 



12.8

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Science – A better tailor than nature

It is bluesign’s contention that by pulling knowledge from the entire spectrum of textile processing, studying natural processes and mimicking them, and taking a holistic approach to synthesizing it all, scientists are able to achieve the best solutions for eco-friendly production. bluesign is constantly updating research and development, as well as its own standard, to maximize the environmental benefits of the products manufactured under its license. New processes, technologies and components are put in place as soon as possible to ensure the best solutions are being used at all times. Looking toward the future, bluesign plans to develop technologies for the polyamide field and for new synthetic fibers produced from sustainable raw materials. In addition, Schoeller is working on developing new processes for the production of nylon. bluesign is also pursuing further developments in process and mechanical engineering, as well as environmental technologies. Among the current projects are the vatting of indigo or copper dyestuffs and waste-water treatment through anaerobic breakdown. Another new development is corfix, a new, patented process technology to be used in pretreatment, dyeing or finishing. The process improves dye absorbency considerably and requires much less energy and water than do other processes currently in use. The machinery to be used in the process is being developed by Switzerland-based Tex-a-Tec, one of bluesign’s technology providers.

13 Processing of recycled polyester fiber in textile industries

13.1 Introduction The waste hierarchy refers to the 3Rs of reduce, reuse and recycle, which classify waste management strategies according to their desirability. The 3Rs meant to be a hierarchy, in order of importance. However in Europe, the waste hierarchy has 5 steps: reduce, reuse, recycle, recovery and disposal. The waste hierarchy has taken many forms over the past decade, but the basic concept has remained the cornerstone of most waste minimization strategies. The aim of the waste hierarchy is to extract the maximum practical benefits from products and to generate the minimum amount of waste. Some waste management experts have recently incorporated a fourth ‘R’: “Rethink”, with the implied meaning that the present system may have fundamental laws, and that a thoroughly effective system of waste management may need an entirely new way of looking waste. Source reduction involves efforts to reduce hazardous waste and other materials by modifying industrial production. Source reduction methods involve changes in manufacturing technology, raw material inputs and product formulation. At the times, the term “pollution prevention” may refer to source reduction. Another method to source reduction is to increase incentives for recycling. Many communities in the United States are implementing variable rate pricing for waste disposal (also known as Pay As You Throw – PAYT), which has been effective in reducing the size of the municipal waste stream. PET (Poly ethylene terephthalate) is used as a raw material for making packaging materials such as bottles and containers for packaging a wide range of food products and other consumer goods. Examples include soft drinks, alcoholic beverages, detergents, cosmetics, pharmaceutical products and edible oils. PET is one of the most common consumer plastics used. Bottles made of PET are recycled to reuse the material out of which they are made and to reduce the amount of waste going to landfills. The empty PET packaging is discarded by the consumer after use and becomes PET waste. In the recycling industry, this is referred to as “post-consumer PET”. Many local governments and waste collection agencies have started to collect post-



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consumer PET separately from other household waste. The collected postconsumer PET is taken to recycling centres known as materials recovery facilities (MRF), where it is sorted and separated from other materials such as metal, objects made out of other rigid plastics such as PVC, HDPE, polypropylene, flexible plastics such as those used for bags (generally low density polyethylene), drink cartons, glass and anything else which is not made out of PET. Post-consumer PET is often sorted into different color fractions: transparent or uncolored PET, blue and green colored PET, and the remainder into a mixed colors fraction.

13.2

Manufacturing process

The further treatment process includes crushing, washing, separating and drying. Recycling companies will further treat the post-consumer PET by shredding the material into small fragments. These fragments still contain residues of the original content, shredded paper labels and plastic caps. These are removed by different processes, resulting in pure PET fragments, or “PET flakes”. Pet flakes are used as the raw material for a range of products that would otherwise be made of polyester. Examples include polyester fibers (a base material for the production of clothing, pillows, carpets, etc.), polyester sheets, strapping, or back into PET bottles, etc. Input raw material – used PET bottles

Cleaning of PET waste

Cutting of waste into small uniform size

Densifying low density raw waste

Cooling of filaments in air quenching unit

Spin assembly for filamentation

Extruded polymer in molten form

Blending in vacuum dyer

Collection of filaments in cans through winders

Drawing, crimping and cutting

Bailing and packing

Melt filtration is typically used to remove contaminants from polymer melts during the extrusion process. There is a mechanical separation of the

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contaminants within a machine called a ‘screen changer,’ a typical system will consist of a steel housing with the filtration media contained in moveable pistons or slide plates that enable the processor to remove the screens from the extruder flow without stopping production. The contaminants are usually collected on woven wire screens which are supported on a stainless steel plate called a ‘breaker plate,’ a stronger circular piece of steel drilled with large holes to allow the flow of the polymer melt. For the recycling of polyester, it is typical to integrate a screen changer into the extrusion line. This can be in a pelletizing, sheet extrusion or strapping tape extrusion line.

13.3

Properties of recycled polyester fiber

(a) Grey PSF fiber Denier – 3 D Cut length – 32–150 mm Colour – Super white Tenacity – 4.8–5.0 GPD Fused fiber –