Textile colors

Resist Printing. In resist printing, print pastes are used that can inhibit the development or fixation of different dyes that are apphed to the textile prior to or after printing. These resists can be of a chemical or mechanical nature, or combine both methods. For example, fiber-reactive dyes, which require alkaU for their fixation, can be made resistant by printing a nonvolatile organic acid, such as tartaric acid, on the textile. Colored resists are obtained by printing pigments with a nonvolatile acid. 

The initial objective of this series of books has been to establish a coherent body of explanatory information on the principles and application technology of relevance for students preparing to take the Associateship examinations of the Society. This particular book has been directed specifically to the subject areas covered by Section A of Paper B the organic chemistry and application of dyes and pigments and of the auxiliaries used with them in textile coloration processes. However, many qualified chemists and colourists interested in the properties of colorants and their auxiliaries have found the First Edition useful as a work of reference. For several reasons it has been convenient to divide the material into two separate volumes 1. Colorants, 2. Auxiliaries. Although fluorescent brighteners share some features in common with colorants, they have been treated as auxiliary products in this book. 

This second volume of the book collects together a remarkable quantity and variety of factual information linking the application properties of auxiliary products in textile coloration and related processes to as much as is known of the chemical structure of these agents. The environmental impact of auxiliary products has become of major importance and developments during the 1990s have necessitated substantial modification and expansion of the text of this volume. The opportunity has also been taken to highlight novel chemical types of auxiliaries that are under evaluation to overcome or avoid many of the drawbacks shown by traditional products. Thus the two volumes of this Second Edition are now approximately equal in size, whereas in the 1990 edition Volume 2 was only about half as big as its sibling. 

The control of pH in textile coloration processes is ensured by three fundamentally different techniques ... 

The most common buffering system containing a weak base together with its salt formed with a strong acid is ammonia with ammonium sulphate. Some useful buffers are obtained from combinations of unrelated acids or bases with salts. The following combinations find occasional use in textile coloration processes, but the acetates and orthophosphates are most frequently used ... 

The potential of crown ethers for use as auxiliaries in textile coloration processes does not appear to have been evaluated recently, although their potential to complex with alkaline-... 

The chemistry of surfactants has been described already. They usually play a subsidiary role in dispersions involved in textile coloration. The polyelectrolytes may be conveniently divided into two categories ... 

The technique of spin dyeing chemical fibers may be located somewhere between the textiles and the plastics area. In contrast to textile coloration, the material which is to be extruded is colored before the fiber is made. The requirements to be met by pigments are therefore similar to those which apply to the coloration of... 

These classes of chemicals contain not only some of the oldest dyes, dating back to the 19th centnry, bnt also some of the most important flnorescent chromophores. The earliest of these discoveries was flnorescein (3.21), which was later brominated to give the polybromo derivative eosin (3.22) (Fignre 3.10). They are of little importance in textile coloration processes bnt are nsed in some fluorescent pigments and extensively in analysis and biological methods and also in tracing the course of water in drains and other water outlets. 

The colors in the Spiro textiles include a rose red, pink, yellow, grey, tan, and brown-black. King and Gardner (22) claim that die textiles were colored by some sort of resist dye methodology. Because pigments must have a binder to paint or coat fiber surfaces they could not have been die source for these colors if a resist technique was in fact the method of Spiro textile coloration. 

Eastern North American archaeological textiles colorant classification, 15-43 colorant testing protocol, 29-39 coloration, literature review, 16-17 fiber and particulate residues, infrared examination, 44-77... 

History. Braun and Tschemak [23] obtained phthalocyanine for the first time in 1907 as a byproduct of the preparation of o-cyanobenzamide from phthalimide and acetic anhydride. However, this discovery was of no special interest at the time. In 1927, de Diesbach and von der Weid prepared CuPc in 23 % yield by treating o-dibromobenzene with copper cyanide in pyridine [24], Instead of the colorless dinitriles, they obtained deep blue CuPc and observed the exceptional stability of their product to sulfuric acid, alkalis, and heat. The third observation of a phthalocyanine was made at Scottish Dyes, in 1929 [25], During the preparation of phthalimide from phthalic anhydride and ammonia in an enamel vessel, a greenish blue impurity appeared. Dunsworth and Drescher carried out a preliminary examination of the compound, which was analyzed as an iron complex. It was formed in a chipped region of the enamel with iron from the vessel. Further experiments yielded FePc, CuPc, and NiPc. It was soon realized that these products could be used as pigments or textile colorants. Linstead et al. at the University of London discovered the structure of phthalocyanines and developed improved synthetic methods for several metal phthalocyanines from 1929 to 1934 [1-11]. The important CuPc could not be protected by a patent, because it had been described earlier in the literature [23], Based on Linstead s work the structure of phthalocyanines was confirmed by several physicochemical measurements [26-32], Methods such as X-ray diffraction or electron microscopy verified the planarity of this macrocyclic system. Properties such as polymorphism, absorption spectra, magnetic and catalytic characteristics, oxidation and reduc-... 

DyStar, formed by the merger of Hoechst and Bayer (1995), acquisition of BASF textile colors which include the former Zeneca, and Mitsubishi of Japan, Germany... 

Perkins W S, Textile Coloration and Finishing, Durham, North Carolina, Carolina, Academic Press, 1996, 224-225. 

Polyanilines (Scheme 36) are conjugated polymers whose it electrons are delocalized over the whole molecule. They are important conducting polymers that also act as semiconductors, in a similar manner to inorganic semiconductors121 m. They are made by chemical or electrochemical (anodic) oxidation of aniline. The product, a poor textile colorant, dates from the 1860s, and is still known by the name given at that time, emeraldine. In the electrochemical process, it is possible to produce thin films directly on conductive substrates. Polyanilines have been used in photoelectrochemical devices124-126. 

Some of these pigments can be made synthetically. They have limited use as textile colorants and pharmaceutical products. 

The general aim of this chapter is to focus on the major instrumental techniques that are used to analyse colorants associated with the textile coloration industries. The principal techniques that have been covered are spectroscopic techniques and chromatographic techniques. The capability and value of the techniques are highlighted by reference to relevant applications. Prior to focusing on the techniques, consideration is given to the nature of colorants and also general issues, such as sampling, that are important in an overall analytical procedure. Section... 

A dye (or dyestuff, as they are sometimes referred to, especially in the USA) is a substance, nearly exclusively organic in nature, that is applied to a substrate in order to impart colour with some degree of permanence. At some point during apphcation dyes are unimolecular, that is, they exist as individual molecules. Dye molecules often contain at least one water solubihsing group, such as a sulphonic acid group, to aid their normal application route, which is usually from an aqueous medium. By far the main application area for dyes is in textile coloration. 

Textile Color Card Association of the United States, Inc., 200 Madison Ave., New York 16, N. Y. Margaret Hayden Rorke, managing director and secretary. 

BASF CoipTFibers Div., Textile Colors A Chemicals, 9401 Anowpoint Blvd., Suite 200, Charlotte, NC 28273 (Tel. 800-247-0557 FAX 704-527-3503)... 

Some of these agencies will be of particular concern to elastomer and polymer composites in particular, such as ISO 105, Parts SOI. S02, and S0.3. which arc concerned with color fastness to hot air.sulfur monochloride and open steam vulcanization, and ISO 105. Part XIO, which is concerned with the assessment of the migration of textile colors into PVC coatings. 

ISO 105. Part XIO. 199.1 Assessment of migration of textile colors into poly vinylchloride coatings. ISO 137. 1975 Wool - Determination of fiber diameter -Projection microscope method. 

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