GB387222A - The manufacture of new polyazodyestuffs - Google Patents

Abstract

Polyazo dyes are made by coupling the tetrazo compounds of diaminomono-, dis- or polyazodyestuffs or the diazo compounds of monoaminodis- or polyazodyestuffs with two or one equimolecular proportions respectively of a hydroxycarbazole coupling component, the components being selected so that at least one contains a group inducing solubility in water. The following dyestuffs are described in examples: (1) 2-naphthylamine-4 : 8-disulphonic acid --> 1-naphthylamine --> 3-amino-4-cresolmethylether --> 1-hydroxycarbazole-3 : 6-disulphonic acid (greyish-blue to blueish-black shades on cotton, silk, viscose, and chrome-leather), (2) 2 - naphthylamine - 7 - sulphonic acid --> p-xylidine --> 1-amino-2-naphtholethylether - 6 - sulphonic acid --> 1-amino-8-hydroxycarbazole-3 : 6-disulphonic acid, (3) 2 - hydroxycarbazole - 7 - sulphonic acid \sM benzidine --> H acid \sM aniline, (4) p-nitraniline --> g -acid (reduced) \sQ 1-amino-8-hydroxycarbazole - 3 : 6 - disulphonic acid (2 mols.). Other components specified are 1 : 8-dihydroxycarbazole-3 : 6-disulphonic acid, 2-hydroxy-3-aminocarbazole (made by N-acetylating 2-hydroxycarbazole, nitrating, reducing and saponifying), 2-hydroxycarbazole 3-carboxylic acid, 7 - hydroxy - a - a - dinaphthocarbazole - 7<1>-sulphonic acid (from the hydrazine of 1-naphthylamine-7-sulphonic acid, and 1 : 7-dioxynaphthalene by Bucherer's method) and 7-hydroxy - a - a - dinaphthocarbazole - 4<1> : 8<1> - disulphonic acid (prepared similarly from the hydrazine of 1-naphthylamine-4 : 8-disulphonic acid). Specification 371,827 is referred to.