Showing posts with label Dyeing. Show all posts

Dirty Laundry - a Greenpeace report on China's Textile Industry Bookmark and Share

Posted by Sazid Rahman

Dirty Laundry
Unraveling the corporate connections to toxic water pollution in China

A new investigative report published on July 13, 2011 from Greenpeace, 'Dirty Laundry', profiles the problem of toxic water pollution resulting from the release of hazardous chemicals by the textile industry in China. The investigation focuses on two facilities that were found to be discharging a range of hazardous and persistent chemicals with hormone-disrupting properties. These results are indicative of a much wider problem that is posing serious and immediate threats to both our precious ecosystems and to human health. Urgent and transparent action is needed in order to eliminate the use and release of these hazardous chemicals.


Dirty Laundry 2: Hung Out to Dry
Unraveling the toxic trail from pipes to products

Research commissioned and published on August 23, 2011 by Greenpeace International has revealed that clothing and certain fabric-based shoes sold internationally by major clothing brands are manufactured using nonylphenol ethoxylates (NPEs). NPEs -- which are used as surfactants in textile production -- subsequently break down to form toxic nonylphenol (NP). Nonylphenol is a persistent chemical with hormone-disrupting properties that builds up in the food chain, and is hazardous even at very low levels.


Video Report




Detox Campaign

Greenpeace is campaigning to stop industry poisoning waterways around the world with hazardous, persistent and hormone-disrupting chemicals. Launched in July 2011, the Detox campaign has exposed links between textile manufacturing facilities causing toxic water pollution in China, and many of the world's top clothing brands.

Nike, Adidas, Puma, H&M, C&A and Li-Ning have committed to Detox, in response to the growing international campaign. Other top clothing companies still need to get a move on, to Detox their brands and help Detox our future.

Test for the harmful azo colorants in textiles Bookmark and Share

Posted by Sazid Rahman

Azo colorants are the most important class of synthetic dyes and pigments, representing 60 - 80% of all organic colorants. They are used widely in substrates such as textile fibres, leather, plastics, papers, hair, mineral oils, waxes, foodstuffs and cosmetics.

Hence azo colorants are part of our everyday colorful life, they are all around us and we could not do without them.

It allows colors with outstanding colorfastness and wide huge spectrum of colors.

Some of these dyes have the capacity to release certain aromatic amines which pose cancer risks. For this reason, the European Union has laid down legislation to prevent exposure to these hazardous amines. This implies that azo dyes containing aromatic amines can no longer be used to dye textile and leather products that may come into contact with the skin.

Please note that all the different parts of the finished product should be tested, and if there are several colors involved, it is not necessary to test them all separately. Only if the general test proves that there are banned azo dyes in the product, more tests will be needed.

Restrictions

EU legislation specifically prohibits the use of the 22 aromatic amines included in the next table in a concentration above the threshold limit of 30 ppm(mg/kg) (detection limit). Please note that all parts of a product should comply with this limit, and that this limit applies to each amine separately. E.g. a textile shoelace of leather footwear needs to comply with the limit of 30 ppm, as well as the leather parts of footwear. It is not allowed to take the average concentration of a certain amine in the complete product.

Table: List of aromatic amines according to the EU Directive 2002/61/EC

Sl. No.

Substance Name

CAS Number

01

Biphenyl-4-ylamin 4-aminobifenyl Xenylamine

92-67-1

02

Benzidine

92-87-5

03

4-chloro-o-toluidine

95-69-2

04

2-naphthylamine

91-59-8

05

o-aminoazotoluene

4-amino-2’,3-dimethylazobenzene

4-o-tolylazo-o-toluidine

97-56-3

06

5-nitro-o-toluidine

99-55-8

07

4-chloroaniline

106-47-8

08

4-methoxy-m-phenylenediamine

615-05-4

09

4,4'-methylenedianiline

4,4'-diaminodiphenylmethane

101-77-9

10

3,3'-dichlorobenzidine

3,3'-dichlorobiphenyl-4,4'-ylenediamine

91-94-1

11

3,3'-dimethoxybenzidine

o-dianisidine

119-90-4

12

3,3'-dimethylbenzidine

4,4'-bi-o-toluidine

119-93-7

13

4,4'-methylenedi-o-toluidine

838-88-0

14

6-methoxy-m-toluidine

p-cresidine

120-71-8

15

4,4'-methylene-bis- (2-chloro-aniline)

2,2'-dichloro-4,4'-methylenedianiline

101-14-4

16

4,4'-oxydianiline

101-80-4

17

4,4'-thiodianiline

139-65-1

18

o-toluidine

2-aminotoluene

95-53-4

19

4-methyl-m-phenylenediamine

95-80-7

20

2,4,5-trimethylaniline

137-17-7

21

o-anisidine

2-methoxyaniline

90-04-0

22

4-amino azobenzene

60-09-3


Articles covered in the EU Directive

Textile and leather products that may come into direct and prolonged contact with the human skin or oral cavity. The examples of products listed are:

• clothing, bedding, towels, hairpieces, wigs, hats, nappies and other sanitary items, sleeping bags;

• footwear, gloves, wristwatch straps, handbags, purses/wallets, briefcases, chair covers, purses worn around the neck;

• textile or leather toys and toys which include textile or leather garments;

• yarn and fabrics intended for use by the final consumer.

Test Methods:

 General Textiles: EN14362-1:2003

 Polyester: EN14362-2:2003

 Leather: CEN ISO/TS 17234:2003

 Determination of P-aminoazobenzene (4-AAB)

Chemistry of aromatic amine release

Azo dyes contain one or more nitrogen-nitrogen double bonds called azo groups in their chemical structure, see Fig. 1.

-N=N -

Fig.1: Azo group

Under reductive conditions using sodium dithionite these azo groups can be cleaved to form 2 amines, which can be schematically shown as in Fig. 2.



Fig.2: Reductive cleavage of the azo dye to form amines

A small number of the aromatic amines are classified as being carcinogenic or potentially carcinogenic to humans. Only those few azo dyes that can release these amines upon reductive cleavage are affected. It has been estimated that less than 4% of known azo dyes structures may release the corresponding amines.

False positive results
For certain dyed goods a listed amine is detected under the conditions of the analytical test even though no banned azo dye is present in the consumer good. The amine is an artifact of the test procedure, resulting from a chemical reaction other than azo cleavage. So, care should be taken that detected aromatic amines originate from azo colorants and not from other materials such as Polyurethane.

Click here to download a test report sample from ITS.

Datacolor Learning Resources Bookmark and Share

Posted by Sazid Rahman

A learning resource from datacolor.com which helps you to use and get the most out of your Datacolor product. The section includes articles on advice and tips as well as in depth discussion on various topics about color applications. Video Learning Library features product training and tutorials.

here's the link

Efficient Water Utilisation in Textile Wet Processing Bookmark and Share

Posted by Sazid Rahman

A paper published in the journal of The Institution of Engineers (India) by Prof S Balachandran and Dr R Rudramoorthy.

Abstract: The amount of water used in various textile wet processing mills vary depending on the equipment, process adopted and types of fabric. However, improper operation and lack of maintenance have resulted in excessive water usage in these units. A recent study on water audit in selected textile processing units at Tirupur cluster have confirmed this fact. Water is becoming scarce and also the quality of available water is deteriorating. Hence it is worthwhile to consider various steps in order to reduce the consumption and also the amount of effluents discharged from the plants. In this paper, a review of various water conservation techniques is being presented so that industry can benefit to a considerable extent by adopting these measures.

Click here to download

Comprehensive View on Garment Dyeing and Finishing Bookmark and Share

Posted by Sazid Rahman

A paper published in the journal of The Institution of Engineers (India) by D Saravanan and T Ramachandran on garment dyeing and finishing.

Click here to download

Dyeing & Finishing Stretch Wovens With Lycra Bookmark and Share

Posted by Sazid Rahman

An achieve document from Invista on Dyeing & Finishing of Stretch Woven Fabrics With Lycra including denim. Thanks to Mr. Bilal Tariq, an experienced textile engineer from Pakistan for providing this document online.

Click here to view the document

Lecture Notes of Textile Engineering Bookmark and Share

Posted by Sazid Rahman

Lecture notes of different courses in textile engineering like Spinning Technology, Weaving Technology, Knitting Technology, Garment Technology, Fabric Design, Polymer Science, Bleaching Dyeing Printing and Finishing of Textile Material, Textile Dyestuffs and Machinery, Fabric Analysis, Textile Costing and Management, Physical Textile Testing and Quality Control, Modern Methods in Textile Manufacturing and many more by Technological University under Ministry of Science and Technology(MOST), Myanmar.

here's the link

Try checking out all the variables on different types of clothing yourself. You can find a wide variety of pieces online for wholesale clothing prices.

Lecture Notes on Preparation, Dyeing and Printing Bookmark and Share

Posted by Sazid Rahman

Presentation on General Requirements for Textile Wet Processing, Preparation, Dyeing and Printing from Dr. Apichart Sonthisombat of Rajamangala Institute of Technology, Thailand.

1. General Requirements for Textile Wet Processing [PDF]
2. Introduction to Textile Preparation [PDF] [PPT]
3. Introduction to Textile Dyeing [PDF] [PPT]
4. Introduction to Textile Printing [PDF] [PPT]

Requirements of Successful ERP Software For A Textile Dye-House Management Bookmark and Share

Posted by Sazid Rahman

Abstract: ERP is a modern concept of any business solution that integrated all the process of a business’ functions including planning, production process, marketing, accounting and supply chain management. Selecting ERP software for a textile dye-house management is very important. As integrating all the functions of a dyeing industry are very complicated, success of ERP software depends upon the capability of simplifying interrelated functions and developing user-friendly interface of software manufacturer. This research study unveils the actual requirements of successful ERP software suitable for dye-house management and also analyzes the available software related to textile dye-house or textile manufacturing in the market.

Click here to download

Chromic Phenomena - The Technological Applications of Colour Chemistry Bookmark and Share

Posted by Sazid Rahman

A book by Peter Bamfield and published by The Royal Society of Chemistry in 2001.

ISBN 0-8404-474-4

Problems With Fiber Reactive Dyeings Not Repeating - A Look at Five Typical Cases Bookmark and Share

Posted by Sazid Rahman

An article on fiber dyeing by By Brent Smith, Keith Beck and Tod Madderra and published in American Dyestuff Reporter.

Click here to download

Troubleshooting In Dyeing Part I & II Bookmark and Share

Posted by Sazid Rahman

An article on troubleshooting methods in dyeing written by Dr. Brent Smith, Dept. of Textile Chemistry, NCSU. These are the first 2 parts in the 12 parts series.

Click here to download

The preparation, dyeing and finishing of knit goods Bookmark and Share

Posted by Sazid Rahman

This is an excellent document on wet processing of knit goods written R.Gordon comprising of four parts:
1. Preparation of knitted cotton fabrics
2. Dyeing of knitted cotton fabrics
3. Dyeing of knitted polyester fabrics
4. Preparation, dyeing and finishing of polyester, and especially polyester microfibres

Click here to download

Trouble Shooting Continuous Thermosol Dyeing Of Polyester Fiber And Blends Bookmark and Share

Posted by Sazid Rahman

An article on Thermosol Dyeing written by Larry Bright, Technical Sales Development Manager, Crompton & Knowles Colors, Inc. and published in American Dyestuff Reporter in August 1996.

Click here to download

Dyes For Synthetics Bookmark and Share

Posted by Sazid Rahman

A document from North Carolina Division of Pollution Prevention and Environmental Assistance. It talks about the application of different dyes for synthetic yarns.

Click here to download

Dyes - Applications, Properties and Equipment Bookmark and Share

Posted by Sazid Rahman

A document from North Carolina Division of Pollution Prevention and Environmental Assistance. It discusses about the properties and application of different classes of dyes.

Click here to download

Color And Color Properties Bookmark and Share

Posted by Sazid Rahman

A note from North Carolina Division of Pollution Prevention and Environmental Assistance on definition of color and various properties of color.

Click here to download

Textile Dyes Bookmark and Share

Posted by Sazid Rahman

A book written by Mansoor Iqbal and published by Rehbar Publishers Karachi

Click here to download

Real-Time Analysis and Control of Batch Dyeing Processes Bookmark and Share

Posted by Sazid Rahman

A research report in the areas of dyebath monitoring, modeling and control by Keith R. Beck, Warren J. Jasper, Ralph McGregor, Gordon K. L Lee, C. Brent Smith of The Dye Applications Research Group (DARG) at North Carolina State University.

Click here to download

Cellulosics Dyeing Bookmark and Share

Posted by Sazid Rahman

A book edited by John Shore and published by the Society of Dyers and Colourists.

ISBN 0 901956 68 6