GB883342A - Water-insoluble heterocyclic monoazobenzene dyestuffs - Google Patents

Abstract

The invention comprises dyes, which are free from acid groups imparting solubility in water, and are of formula A-N=N-B where A is the residue of a heterocyclic diazo-component, free from alkylsulphonyl groups, and B is the residue of an N,N-dicyanethylaniline which couples in p-position to the amino group. The dyes are made in conventional fashion by coupling appropriate heterocyclic-diazo components with the required coupling component. Preferably the dyes are of formula <FORM:0883342/IV (c)/1> where X is H or alkyl, Y is H or NO2, R1 is H, halogen, alkyl, alkoxy or aliphatic acylamino and R2 is H, p alkyl or alkoxy. Representative of specified diazo components are: 2-amino-6-nitrobenzthiazole, 2-amino-5-cyanothiazole, 2-amino-3 - nitro - 5 - acetylthiophene and 5 - amino - 3 - methoxy-thio (1)-diazole-(2,4). Representative of specified coupling components are: 1-(N-bis-cyanethyl)-amino-3-methyl- and -acetylamino- and -2,5-dimethoxy-benzenes. The dyes colour polyamides and especially fibres of cellulose acetate, artificial silk, cellulose triacetate and polyethylene terephthalate. Examples are provided of the preparation of the dyes and their use in colouring processes. Orange, red and violet shades are obtained. Specifications 723,933 and 760,618 are referred to.