Patent GB-294583-A (GB)
Title: Manufacture of azo-dyestuffs and the application thereof
Filed: 1928-07-26
Abstract: 294,583. Soc. of Chemical Industry in Basle. July 26, 1927, [Convention date]. Azo dyes applicable as varnish colours are obtained by coupling diazo, diazoazo, or tetrazo compounds derived from homologues or substitution products of aniline and containing neither a sulphonor carboxylgroup with a pyrazolone carboxylic acid ester resulting from the condensation of an oxalacetic acid ester with hydrazine. The following examples are specified. (1) The dyestuff m-nitro-p-toluidine # (coupled alkaline) 5-pyrazolone-3-carboxylic acid ethyl ester is suitable for colouring cellulose ester varnishes clear yellow tints, fast to light, and similar yellow to red products are obtained from diazotized o-, m-, and p-chloranilines, o-, and p-toluidines, 2 : 5- and 3 : 4-dichloranilines, m-, and p-xylidines, o-nitro-p-toluidine, o-, m-, and p-nitranilines, p-chloro-o-nitraniline and o-nitraniline-psulphamide, and from tetrazotized benzidine, dianisidine, and m : m<1>- or p : p<1>-diaminodiphenylurea. (2) 4 to 5 Parts of the dyestuff m-nitro-ptoluidine # the ethyl ester of 5-pyrazolone-3- carboxylic acid are dissolved in 1000 parts of Zapon varnish; the product gives transparent yellow coatings on metal, glass, leather, wood, celluloid, or silk, suitable additions being incorporated when a matt or covering varnish is required. The Specification, as open to inspection under Sect. 91 (3) (a) comprises also the azo dyestuffs obtained by coupling any diazo, diazoazo or tetrazo compound with the pyrazolones resulting from the condensation of oxalacetic esters with hydrazine which are applicable also as acid, direct cotton or mordant dyestuffs and certain of them are convertible into dyestuffs containing metal, e.g. copper or chromium. The following examples are given. (1) The dyestuff 2-naphthylamine-1-sulphonic acid # 5-pyrazolone-3-carboxylic acid dyes wool yellow; similar products are obtained with other naphthylamine sulphonic acids, or aniline sulphonic acids or aminoazobenzene sulphonic acid, or aminoazotoluene disulphonic acid as diazo components, and direct dyeing yellow cotton dyestuffs are obtained with dihydrothiotoluidinesulphonic acid as diazo component and with 4 : 4<1>-diaminodiphenylurea disulphonic acid as tetrazo component. (2) The dyestuff aniline (or a- or #-naphthylamine) # 5- pyrazolone-3-carboxylic acid ethyl ester is suitable for colouring Zapon varnish. (3) The dyestuff 4-chloro-2-aminophenol-5 (or 6-) sulphonic acid # 5-pyrazolone-3-carboxylic acid dyes wool in an acid bath orange tints which become bluered on after-chroming; the corresponding dyestuffs with 4-nitro-2-aminophenol-6-sulphonic acid and 6-nitro-2-aminophenol-4-sulphonic acid as diazo components give red-brown to brown tints when after-chromed on wool, and the dyestuffs with 1 : 2-aminonaphthol-4-sulphonic acid and its nitration product as diazo components give violet or bordeaux tints on after-chroming; the copper and chromium compounds of these dyestuffs give yellow-brown to red-brown and yellow to bluered dyeings respectively and are also suitable for colouring varnishes. (4) The dyestuff anthranilic acid # 5-pyrazolone-3-carboxylic acid gives yellow-orange tints, fast to light and chlorine, when chrome-printed on cotton, and other chromeprinting dyestuffs are obtained with picramic acid, 4-chlor-2-aminophenol, 4-sulpho-2-aminophenol-6-carboxylic acid, 4-nitro-2-aminophenol-6- carboxylic acid, and 4-chloro-2-aminophenol-6- carboxylic acid as diazo components. (5) The dyestuffs aminoazobenzenesulphonic acid # 5- pyrazolone-3-carboxylic acid gives intense yelloworange dyeings on wool. (6) 4 to 5 parts of the dyestuff aniline # the ethyl ester of 5-pyrazolone-3-carboxylic acid are dissolved in 1000 parts of Zapon varnish; the product gives transparent greenish-yellow coatings on metal, glass, leather, wood, celluloid, or silk, suitable additions being incorporated when a matt or covering varnish is required. (7) Goods are dyed red with the dyestuff 4-chloro-2-amino-phenol-6-sulphonic acid # 5-pyrazolone-3-carboxylic acid in a bath containing acetic acid and Glaubers salt, sulphuric acid, and potassium bichromate. (8) Goods are printed a fast orange tint with a paste containing a solution of the dyestuff anthranilic acid # 5- pyrazolone-3-carboxylic acid in dilute caustic soda, starch tragacanth thickening, acetic acid, and chromium acetate, and the printed goods are dried, steamed, washed, treated with diastase, and soaped. This subject-matter does not appear in the Specification as accepted.