Pigments and dyestuffs

The special topics discussed are (i) the biological aspects of heterocyclic compounds, i.e. their biosynthesis, toxicity, metabolism, role in biochemical pathways, and their uses as pharmaceuticals, agrochemicals and veterinary products (ii) the use of heterocyclic compounds in polymers, dyestuffs and pigments, photographic chemicals, semiconductors and additives of various kinds and (iii) the use of heterocyclic compounds as intermediates in the synthesis of non-heterocyclic compounds. 

For the dyestuff and pigment industry, a better knowledge of dediazoniation under such conditions would be useful because we estimate the loss in yields of industrially produced azo compounds due to competitive (unwanted) dediazoniations to be at least 10% of the production. These 10% are mainly diazo tars which have been investigated systematically in only three papers since the 1950s124. 

The main differentiating performance characteristic between dyestuffs and pigments is solubility. During their application, dyestuffs are solubilised, either in the medium or the hbre and hence lose any particular aspect of their crystal structure or physical form. Pigments, on the other hand, remain practically insoluble during their application processes, thus retaining aspects of their morphology, which are of importance to both their colour and performance. 

Specialty chemicals are formulations of chemicals containing one or more fine chemicals as active ingredients. They are identified according to performance properties. Customers are trades outside the chemical industry and the public. Specialty chemicals are usually sold under brand names. Suppliers have to provide product information. Subcategories are adhesives, agrochemicals, biocides, catalysts, dyestuffs and pigments, enzymes, electronic chemicals, flavors and fragrances, food and feed additives, pharmaceuticals, and specialty polymers (see Chapter 11). 

Specialties 55% ( 990 billion) Additives and catalysts Biocides Dyestuffs and pigments Electronic chemicals Flavors and fragrances Food and feed additives Household and personal care Life science products Specialty polymers / Pharmaceuticals Veterinary drugs Agrochemicals... 

Dyestuffs and pigments Cellulosic vat dye Indanthren 6,15-Dihydro-5,14,18- anthrazinetetrone Dystar, Germany... 

Overall, dyestuff and pigments offer limited business opportunities for Western fine-chemical companies with their sophisticated multipurpose plants and high SHE requirements. 

The preparation of chromium(III) and cobalt(III) complexes of tetradentate formazans in which the coordination sphere of the metal is completed by a variety of neutral ligands has been reported116 and these (185) were claimed to be very stable towards acids. By analogy with copper complexes, however, some doubt must exist regarding the structures assigned to those complexes derived from l,5-bis(2-carboxyphenyl)formazans. Various dyestuff and pigment applications have... 

Metal complexes of hydroxyanthraquinones are now only of historical interest in the dyestuffs and pigments field. Despite the very attractive shades and extremely good fastness properties of dyeings produced on cotton using the mordant technique with dyes of this type, they have been... 

There is a big market for intense colours for dyeing cloth, colouring plastic and paper, painting walls, and so on. This is the dyestuffs and pigments industry and leaders here are companies like ICI and Akzo Nobel. TCI have a large stake in this aspect of the business, their paints turnover alone being 2 003 000 000 in 1995. 

Fixation of dyestuffs and pigments by incorporation in the crosslinked cellulose and in the finish network, also providing better wet fastness for conventional dyeings and printings Cellulosics mainly with direct and acid dyes, cotton/polyester blends with reactive dyes, preparation for dry heat transfer printing of cellulosics ... 

Dyestuffs and pigments, textile chemicals, equipment, an alphabetical list of new products developed since November of the previous year. 

Runox. [Toho Chem. Industry] Condensed ntqrhthalene sulfonate dispersant for dyestuffs and pigments detergents, rust preventives for metal surfaces rust and paint remover. 

Dyestuffs and pigments, e.g., chrome yellow, food color, titanium dioxide, paint pigments, etc. Fertilizers, e.g., nitrates, ammonium salts, phosphates, etc. 

Modern developments in the dyestuff and pigment sector are luster pigments, IR-reflectors for house facades and windows, light-harvesting systems for solar collectors and light-emitting diodes in the electronic industry (Fig. 2.3). 

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