GB309216A - Manufacture of fast azo-dyestuffs - Google Patents

Abstract

309,216. Imray, O. Y., (I. G. Farbenindustrie Akt.-Ges.). Dec, 31, 1927. Azo dyes; lakes.-Azo dyes are made by coupling diazotized 2: 4: 5-trichloroaniline with an arylide of 2: 3-hydroxynaphthoic acid. They are especially fast to light and may be used for lakes. According to examples, (1) diazotized 2:4:5- trichlcraniline is coupled with 2<1>-hydroxy-3<1>- naphthoyl-2-amino-1-anisol dissolved in caustic soda solution containing Turkey red oil and sodium Acetate; the product forms a yellowish red lake with the usual substrata. Other specified arylides are produced from 2: 3-hydroxynaphthoic acid and a- or #-naphthylamine, p-anisidine, aminohydroquinone dimethylether, 4- and 5-chlor-2-anisidine, 5-chloro-2-toluidine, dianisidine, aniline. p-phenetidine, o, m-, or p-chloraniline and m-toluidine and from 6-bromo-2 : 3- hydroxynaphthoic acid and 2-amino-5-chlorhydroquinone dimethylether. 6<1> - Bromo-2<1>-hydroxy-3<1>-naphthoyl-2-amino-5- chlorohydroquinone dimethylether is prepaered from 6-bromo-2: 3-hydroxynaphthoic acid and 2- amino - 5 - chlorobydroquinone dimethylether according to the process of Specification 23732/13. 2-Amino-5-chlorohydroquinonedimathylether is prepared by replacing the amino-groups of 5- amino-2-nitrydroquinone dimethylether by chlorine and reducing the nitro-group. Reference has been directed by the Comptroller to Specifications 6379/12, and 17279/13, [Class 15 (ii), Dyeing, Processes &c. for].