Dyes, azoic disperse

Depolymerised Carpet printing/dyeing acid, metal-complex dyes Cotton, viscose vat, direct, azoic dyes Polyester disperse dyes Nylon acid, metal-complex dyes Acrylic fibres basic dyes... 

Acid dyes Azoic colouring matters Basic dyes Developers Direct dyes Disperse dyes Fluorescent dyes Food dyes Ingrain dyes Leather dyes Mordant dyes Natural dyes Oxidation dyes Pigments Reactive dyes Reducing agents Solvent dyes Sulphur dyes Condense sulphur dyes Vat dyes... 

Note on polyamide (PA) and wool dyes. PA fibres can be dyed with a wide range of dyes, but disperse azoic, acid 1 2 metal complex acid and reactive dyes are mainly used. 

There are, of course, many varieties in each of these chemical classifications, so that the result is hundreds of individual dyes each with its own specific characteristics for hue and use on substrates. Dyers have arranged this very complex and large group of chemical products into ten categories arranged by the method of application to the fiber or substrate acid dyes, azoic dyes, basic dyes, direct dyes, disperse dyes, reactive dyes, solvent dyes, sulfur dyes, vat dyes, and mordant dyes. It is in these categories that dyestuffs are discussed in the trade. 

Phloroglucinol is Hsted in the Colourindex as Cl Developer 19. It is particularly valuable in the dyeing of acetate fiber but also has been used as a coupler for azoic colors in viscose, Odon, cotton (qv), rayon, or nylon fibers, or in union fabrics containing these fibers (157). For example, cellulose acetate fabric is treated with an aromatic amine such as (9-dianisidine or a disperse dye such as A-hydroxyphenylazo-2-naphthylamine and the amine diazotizes on the fiber the fabric is then rinsed, freed of excess nitrite, and the azo color is developed in a phloroglucinol bath at pH 5—7. Depending on the diazo precursor used, intense blue to jet-black shades can be obtained with excellent light-, bleach-, and mbfastness. 

Sulfonic Acid-Based Dyestuffs. Sulfonic acid-derived dyes are utilized industrially in the areas of textiles (qv), paper, cosmetics (qv), foods, detergents, soaps, leather, and inks, both as reactive and disperse dyes. Of the principal classes of dyes, sulfonic acid derivatives find utiUty in the areas of acid, azoic, direct, disperse, and fiber-reactive dyes. In 1994, 120,930 t of synthetic dyes were manufactured in the United States, of which 5,600 t were acidic (74). The three largest manufacturers of sulfonic acid-based dyes for use in the United States are BASF, Bayer, and Ciba-Geigy. 

The only disperse brown of commercial importance is Disperse Brown 1 (101), which in 1988 had sales in excess of 2.3 million (production 317 tons). A method stiU. in use to produce navy and black shades economically on acetate involves formation of the dye direcdy on the substrate (azoic dyeing). 

Acetate fibers are dyed usually with disperse dyes specially synthesized for these fibers. They tend to have lower molecular size (low and medium energy dyes) and contain polar groups presumably to enhance the forces of attraction by hydrogen bonding with the numerous potential sites in the cellulose acetate polymer (see Fibers cellulose esters). Other dyes can be appHed to acetates such as acid dyes with selected solvents, and azoic or ingrain dyes can be apphed especially for black colorants. However thek use is very limited. 

Azo dyes are by far the largest family of organic dyes. They play a prominent role in acid, direct, reactive, azoic, and disperse dye structures, as shown previously, and include structures that cover the full color spectrum. Generally, the synthesis of azo dyes involves a process known as diazo coupling. In this... 

Softeners on dyed polyester often cause more disperse dye migration (especially thermomigration) and cause reduced crocking fastness. This is similar to softeners on the basis of fatty acids and azoic dyeings. 

Terylene is highly crystalline and markedly hydrophobic. It is not, there-, easily penetrated by dyes with large molecules. It also has no chemic-active groups and cannot combine with dye anions or cations. In ractice, polyester fibres are dyed with disperse dyes, a few azoic combinations, and with those disperse dyes which can be diazotized and coupled in situ. 

Serviprint [Chonloid) Printing assistants for pigments, vat, disperse, fiber reactive, azoic, and add dyes. 

OTHER COMMENTS o-anisidine is used as an intermediate in the manufacture of azo dyes and in the production of Solvent Red 1 used to prepare guaiacol via diazotization and hydrolysis p-anisidine is used in the manufacture of azo dyes and as a chemical intermediate for Vat Red 29, Disperse Orange 15, and Azoic Coupling Component 13. 

Dye allergens are found in the disperse, acid, azoic, basic, direct, pigment, reactive, solvent, and vat application classes. No dye allergens belong to the mordant and sulfur application classes. Almost 50% of the 70 reported dye allergens are disperse, about 20% are reactive, and 10% are acid. 

In certain cases, identifying the specific garment or textile product and the allergen it contains will be an important undertaking. The fiber content of the fabric will narrow the possible dyes, as certain dyes are used to color certain fibers. Cotton, rayon, and linen fabrics are dyed with direct, fiber-reactive, mordant, azoic, sulfur, and vat dyes. Wool fabrics are dyed with acid, mordant, and fiber-reactive dyes. Polyester fabrics are dyed with disperse dyes unless the polyester is modified to accept basic dyes. Nylon fabrics are colored with acid and disperse dyes unless modified to accept basic dyes. Acrylic fabrics are dyed with basic and disperse dyes. Acetate fabrics are dyed with disperse dyes. Other synthetic fibers are dyed with disperse dyes. 

Disperse yellow 3 is an azoic dye responsible for occupational contact dermatitis in workers in the textile industry. It can be found in some semipermanent hair dyes. 

Azoic dyes from cotton fibers can be extracted with anhydrous acetic acid by heating in a sealed tube at lOO C and separated on Kiesel gel 6OF254TLC plates using chlorobenzene-1,2 dichloroeth-ene-acetone (20 20 1) as mobile phase (51b). Disperse, cationic, and other dyes can be extracted from fibers with DMF/chlorobenzene, 50% formic acid, and NH3 solution, respectively (51c). 

Effect of Heat Sticks at 230C Melts at 260C Acceptance of Dye Disperse and azoic dyestuffs recommended Available in a wide variety of solution dyed colors, including black for automotive applications. 

Infrared epectroecopy spect The study of the properties of material systems by meansof their interaction with infrared radiation ordinarily the radiation is dispersed into a spectrum after passing through the material. lin fralred spek tras-ko-pS Infuelon chem The aqueous solution of a soluble constituent of a substance as the result of the substance s steeping in the solvent for a period of time. in fyii-zhon ) Ingrain color See azoic dye. in,gran. kal ar)... 

---