Dyeing textiles

Production of colored textiles is one of the basic technologies in human civilization. Textile consumption is steadily increasing worldwide, following the growth of world population and stimulated by a growing GDP in many countries, primarily in Asia. Synthetic fibers increased their share, particularly polyester fibers see (Table 4.1). 

Cellulosics and polyester together account for 78 % of world textile consumption. Following this trend, disperse dyes and dyes for cellulosic fibers reclaimed the principal market share (Table 4.2). 

Dye class Market share, 109DM Market share, % 

In preindustrial times, textiles were dyed primarily with plant dyes. Dyeing with animal dyes (kermes, Tyrian purple) was restricted to special cases. Today, synthetic dyes are used almost exclusively. However, use of natural dyes is again increasing [1, 2, 3, 4], 

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Cyanine Dyes Derived from Thiazolium Salts 2. Textile Dyes... 

Textile applications Textile bags Textile bleaching Textile cord Textile dyeing Textile fibers Textile finishes Textile finishing... 

Textile dyes were, until the nineteenth century invention of aniline dyes, derived from biological sources plants or animals, eg, insects or, as in the case of the highly prized classical dyestuff Tyrian purple, a shellfish. Some of these natural dyes are so-caUed vat dyes, eg, indigo and Tyrian purple, in which a chemical modification after binding to the fiber results in the intended color. Some others are direct dyes, eg, walnut sheU and safflower, that can be apphed directly to the fiber. The majority, however, are mordant dyes a metal salt precipitated onto the fiber facUitates the binding of the dyestuff Aluminum, iron, and tin salts ate the most common historical mordants. The color of the dyed textile depends on the mordant used for example, cochineal is crimson when mordanted with aluminum, purple with iron, and scarlet with tin (see Dyes AND DYE INTERMEDIATES). 

Ammonium acetate has limited commercial uses. It serves as an analytical reagent, and in the production of foam mbber and vinyl plastics it is also used as a diaphoretic and diuretic in pharmaceutical appHcations. The salt has some importance as a mordant in textile dyeing. In a hot dye bath, gradual volatilization of ammonia from the ammonium acetate causes the dye solution to become progressively more acidic. This increase in acidity enhances the color and permanence of the dyeing process. 

Glycol Ethers. Glycol ethers are produced by reaction of propylene oxide with various alcohols such as methanol, ethanol, butanol, and phenol. The products are the mono-, di-, and tripropylene glycol ethers. These products are used in protective coatings, inks, textile dyeing, cleaners, antiicing additives for jet fuel, and as chemical intermediates (276). 

Other Uses. Other appHcations for sodium nitrite include the syntheses of saccharin [81-07-2] (see Sweeteners), synthetic caffeine [58-08-2] (22), fluoroaromatics (23), and other pharmaceuticals (qv), pesticides (qv), and organic substances as an inhibitor of polymerization (24) in the production of foam blowing agents (25) in removing H2S from natural gas (26) in textile dyeing (see Textiles) as an analytical reagent and as an antidote for cyanide poisoning (see Cyanides). 

Rehable estimates of annual production of biphenyl in the United States are difficult to obtain. The 1990 figure is probably on the order of 16 million kg/yr of which about half is derived from hydrodealkylation sources. About 10% of the biphenyl derived from HD A sources is consumed, as 93—95% grade, in textile dye carrier appHcations. The remainder is used for alkylation or upgraded to >99.9% grades for heat-transfer purposes. Essentially all of the high purity biphenyl produced by dehydrocondensation of ben2ene is used as alkylation feedstock or is utili2ed directly in heat-transfer appHcations. 

Corrosion inhibitors Cosmetics, drugs Electrical insulation Electrolytic refining Fertilizers Fire retardants Glass and glass wool Herbicides Insecticides Leather tanning Photography Textile dyes Wax emulsifier Wool preservatives... 

Sodium Tetrahydroborate, Na[BH ]. This air-stable white powder, commonly referred to as sodium borohydride, is the most widely commercialized boron hydride material. It is used in a variety of industrial processes including bleaching of paper pulp and clays, preparation and purification of organic chemicals and pharmaceuticals, textile dye reduction, recovery of valuable metals, wastewater treatment, and production of dithionite compounds. Sodium borohydride is produced in the United States by Morton International, Inc., the Alfa Division of Johnson Matthey, Inc., and Covan Limited, with Morton International supplying about 75% of market. More than six million pounds of this material suppHed as powder, pellets, and aqueous solution, were produced in 1990. 

Benzyl-derived quaternary ammonium compounds are used widely as cationic surface-active agents and as germicides, fungicides, and sanitizers. Benzyl alcohol is used in a wide spectmm of appHcations including pharmaceuticals and perfumes, as a solvent, and as a textile dye assistant. 

In 1980, approximately 111,000 t of synthetic organic dyestuffs were produced in the United States alone. In addition, another 13,000 t were imported. The largest consumer of these dyes is the textile industry accounting for two-thirds of the market (246). Recent estimates indicate 12% of the synthetic textile dyes used yearly are lost to waste streams during dyestuff manufacturing and textile processing operations. Approximately 20% of these losses enter the environment through effluents from wastewater treatment plants (3). 

E. J. Weber, Fate of Textile Dyes in the Aquatic Environment Degradation of Disperse Blue 79 in Anaerobic Sediment-Water Systems, Environmental Research Laboratory, U.S. EPA, Athens, Ga., Mar. 1988. 

Use Textile Dyes and Pigments, Parts I, II, and III, Impedal Chemical Industdes PLC, Organics Division, Manchester, UK, 1986, 1987. 

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