Leather Solvent Dyes

Solvent dyes are also used for tinting transparent varnishes and lacquers in the furniture and leather industries, where the surface texture of the finished articles needs to be protected but not obscured. There is also a growing demand for coloured but transparent inks for printing on the ever-increasing amounts of plastic packaging of all kinds used for the food sold in supermarkets. 

Other Dyes. Other dye classes listed in the Colour Index include dyes lor leather, solvents, paper, and food. Leather dyes arc those acid, direct, mordant, and basic dyes that show substamivily for leather, good diffusion into it. and acceptable fastness. They are essentially applied in an analogous... 

Commercial solvent dyes for leather are employed in a great variety of solvents. It is common practice to use mixed solvents to obtain the requisite physical properties. They are also applied to correct off-shade dyeings and improve the brilliance of shades. Alcohols or glycols are the most common solvents but esters and ketones are also convenient. The colors are normally applied to dyed or undyed tanned leather by spraying from solvent solution or aqueous/organic emulsions. Nowadays, water-based finish recipes, which are combinations of sol-... 

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... 

Uses Metalized dye for leather spray dyeing applies., wood stains, solvent inks, decorative coatings on metal foils and polymeric films Features Provides high lightfastness Properties Sol. in alcohol and various polar soivs. 

Uses Solubilizer solvent for many org. and inorg. compds., plastic films dye solvent, dye assistant for textiles mfg. of methylamine denaturing alcohol In organic synthesis drug intermediate in mfg. of ampicillin, cephaclor, etc. solder flux ingred. plasticizer in leather, cloth films, coatings stabilizer humectant in paper accelerator buffer in lacquers, explosives, cosmetics prep, of hypnotics photochemicals biocides cryoscopy vehicle in pharmaceuticals antidote... 

Storage Hygroscopic store in a tightly closed container in a cool, dry, well-ventilated area away from incompat. substances Uses Basic dye for bast, silk, leather solvent... 

Acid dyes Reactive dyes Basic Direct dyes Mordant dyes Disperse dyes Vat dyes Solvent dyes Fluorescent brightners Other dye classes Nylon, sUk, wool, paper, inks and leather Cotton, wool, sUk and nylon Paper, polyacrylonitrile, modified nylon, polyester and inks Cotton, rayon, paper, leather and nylon Wool, leather and anodised altiminirun Polyester, polyamide, acetate, acrylic and plastics Cotton, rayon and wool Plastics, gasoline, varnishes, lacquers, stains, inks, fats, oils and waxes Soaps and detergents, aU fibres, oils, paints and plastics Food, drugs and cosmetics, electrography, direct and thermal transfer printing... 

Acetic acid is both a reactant and solvent in the manufacture of cellulose acetate, polyester fibers, and plastics. Other products that utilize acetic acid as a reactant include vinyl acetate, ester solvents, dyes, metallic salts, pharmaceuticals, and pesticides. Formic acid is used in textile dyeing and finishing, leather tanning and treatment, pharmaceuticals, and the synthesis of the versatile methyl formate solvent. n-Butanoic acid is used in the preparation of cellulose acetate butyrates used for lacquers and molding plastic compositions. The acid is also used for the production of useful coating ester solvents, plasticizers, and pharmaceuticals. 

Basic dyes are water-soluble in the form of their salts and are used for colouring paper, leather, cellulose- and polyacrylonitrile fibres. The free bases dissolve in many organic solvents and find application similar to that of the solvent dyes. Basic dyes can function as pigments in lacquer form. Mixtures of basic dyes are usually responsible for brown, green and black tones. 

Basic Violet 10 (Rhodamine B) is a dye for bast fibers, mordanted cotton, leather, and paper. Its salts with certain acids and acid dyes provide pigments (Pigment Violet 1, Pigment Red 173) and solvent dyes (Solvent Red 35, Solvent Red 109). Basic Violet 10 is prepared by condensing phthalic anhydride with m-diethylaminophenol and treating with hydrochloric acid. This is the general preparative route for rhodamines. 

Uses. Tetrahydrofurfuryl alcohol is of interest in chemical and related industries where low toxicity and minimal environmental impact are important (134). For many years tetrahydrofurfuryl alcohol has been used as a specialty organic solvent. The fastest growing appHcations are in formulations for cleaners (135) and paint strippers (136), often as a replacement for chlorinated solvents (137). Other major appHcations include formulations for crop sprays, water-based paints, and the dyeing and finishing of textiles and leathers. Tetrahydrofurfuryl alcohol also finds appHcation as an intermediate in pharmaceutical appHcations. 

Phthalocyanine Dyes. In addition to their use as pigments, the phthalocyanines have found widespread appHcation as dyestuffs, eg, direct and reactive dyes, water-soluble dyes with physical or chemical binding, solvent-soluble dyes with physical or chemical binding, a2o reactive dyes, a2o nonreactive dyes, sulfur dyes, and wet dyes. The first phthalocyanine dyes were used in the early 1930s to dye textiles like cotton (qv). The water-soluble forms Hke sodium salts of copper phthalocyanine disulfonic acid. Direct Blue 86 [1330-38-7] (Cl 74180), Direct Blue 87 [1330-39-8] (Cl 74200), Acid Blue 249 [36485-85-5] (Cl 74220), and their derivatives are used to dye natural and synthetic textiles (qv), paper, and leather (qv). The sodium salt of cobalt phthalocyanine, ie. Vat Blue 29 [1328-50-3] (Cl 74140) is mostly appHed to ceUulose fibers (qv). 

The condensation on the fabric of 1-amino-3-iminoisoindo1enines or 2-amino-5-iminopyrro1enines with phloroglucinol, preferably in the presence of metal salts and solvents, yields fast dyeings in brown shades (158). Metallized azo dyes derived from phloroglucinol yield fast dyeings on leather (qv) or silk (qv) (159). 

Lack-industrie,/. (paint and) varnish industry, -lack, m. lac lake, -lasurfarbe,/. transparent varnish color, -laus,/. lac insect, -lausfarb-stoff, m. lac dye. -leder, n. japanned leather, patent leather, -leinol, n. linseed oil for varnish. -losungsmittel, n. lacquer solvent. 

Uses Solvent for celluloid, cellulose acetate, fats, oils, waxes, nitrocellulose and resins wood preservatives rayon and artificial leather imitation gold leaf extraction of resins and waxes in antifreeze mixtures and hydraulic fluids laboratory reagent preservative for animal tissue dyeing mixtures stripping agent for textiles. 

Uses Preparation of 3,4-dichloroaniline solvent for a wide variety of organic compounds and for oxides of nonferrous metals solvent carrier in products of toluene diisocyanate intermediate for dyes fumigant insecticide for termites degreasing hides and wool metal polishes degreasing agent for metals, wood, and leather industrial air control disinfectant heat transfer medium. 

Uses Solvent for natural and synthetic resins, cellulose acetate, nitrocellulose, and some dyes nail polishes dyeing leather sealing moisture-proof cellophane lacquers, varnishes, enamels, wood stains in solvent mixtures perfume fixative jet fuel de-icing additive. 

Uses. Used in semiconductor industry as a photoresist solvent for nitrocellulose lacquers and alkyd resins in dyeing textiles and leather in cleaners and varnish removers... 

Levin et al. (1987), in a letter to the editor, described three cases of embryonal-cell carcinoma of the testis in workers at one leather tannery in the United States. According to the authors, all the tanneries they had surveyed used dimethylformamide, as well as a wide range of dyes and solvents. A screening effort to identify additional testicular cancers at the leather tannery with the three cases was undertaken in 1989 (Calvert et al., 1990). Fifty-one of 83 workers employed at the plant between 1975 and 1989 participated. No additional case of testicular cancer was identified. 

Acetamide has been produced commercially since the 1920s, but it is not certain that it is still in commercial use, although it was previously used as an intermediate in the synthesis of methylamine, thioacetamide, hypnotics, insecticides, medicinals and various plastics, a solvent, a soldering flux ingredient, a wetting agent and penetration accelerator for dyes, and as a plasticizer in leather, cloth and coatings (IARC, 1974). 

---