GB452300A - Process for the manufacture of tris- and tetrakis-azodyestuffs - Google Patents

Abstract

Tris- and tetrakisazo dyes are made by combining, in an alkaline medium, the diazoazo compound formed in an acid medium from 1 mol. of a 4 : 4<1>-tetrazodiphenyl and 1 mol. of a periaminonaphthol sulphonic acid with a monodiazo or diazoazo compound and finally coupling with a m-phenylene diamine having one of the amino groups acylated other than by a sulphonyl group and the hydrogen atoms of the other amino group entirely or partly replaced by unsubstituted or substituted alkyl, aralkyl or aryl groups. The process may be modified by combining in an alkaline medium the azo compounds obtainable by coupling, in an acid medium, one mol. of a monodiazo compound of the benzene series containing a substituent convertible into the amino group, with one mol. of a periaminonaphthol sulphonic acid, with a monodiazo or diazoazo compound, converting the specified group into the amino group, diazotizing, and finally coupling with the m-phenylene diamine derivative. They yield black shades on cellulose fibres and leather fast to acids. In examples, dyes are described from the following components: benzidine and its 2 : 2<1>disulphonic, 3 : 3<1>-dichloro- and 3 : 3<1>-dicarboxy derivatives, p-nitroaniline; H and K acids; p-sulphanilic acid, aniline, o-, m-, or p-aminobenzoic acid, 4-aminoazobenzene-4<1>-sulphonic acid, p-nitroaniline, naphthionic acid, a -naphthylamine, aminoazobenzene sulphonic acids; diethyl-m-aminoacetanilide, 1-methyl-2-dimethylamino - 4 - acetylaminobenzene, m-benzoylaminodimethylaniline, monohydroxyethylamino-, dihydroxyalkylamino- or hydroxyalkylalkylamino-m-acetanilides; oxalyl and phthaloyl compounds are also mentioned.