GB889471A - Water-soluble quaternary ammonium salts of monoazodyestuffs and process for their manufacture - Google Patents

Abstract

The invention comprises dyes, which are free from sulpnonic acid groups, and are of formula A-N=N-B where A is a benzene residue containing a nitro group ortho to the azo link and B is the residue of a 5-pyrazolone bound in the 4-position to the azo p link, which contains a group of formula NHCOPQ+X- where P is an aliphatic residue, Q is a quaternary ammonium group and X an anion. The dyes may be made by diazotisation and coupling from appropriate nitranilines and pyrazolones, coupling being preferred in a weakly acid or neutral medium, by treating appropriate dyes containing NHCOPX or NHCOPZ groups, where X is Hlg and Z is a secondary or tertiary amino residue, with a tertiary amine or alkylating agent respectively, or by treating an appropriate dye containing an acylatable amino group with a halide of an aliphatic monocarboxylic acid containing a quaternary ammonium group. A may have further substituents, e.g. halogen, lower alkyl or alkoxy or CF3 groups. B has a benzene residue advantageoulsy in the 1-position and an alkyl, benzene or carbalkoxy residue in the 3-position. The quaternary acylamino residue is advantageously bound to the benzene residue in the 1-position. Amongst specified diazo components are 2-nitraniline and 1-amino-2-nitro-4-methyl-, -chloro- and -cyano-benzene. Advantageously NHCOPQ+X- is <FORM:0889471/IV (c)/1> where R1, R2, and R3 each are alkyl, cycloalkyl or aralkyl or 2 or 3 of the R's may, with N, form a heterocyclic ring, X is an anion, n is an integer not greater than 8 and m is 1 or 2. Preferred are dyes of formula <FORM:0889471/IV (c)/2> where Y is H, Hlg, Alk or OAlk, R4 is alkyl, phenyl or carbalkoxy and R1, R2, R3, X, m and n are as above and advantageously have a residue of a strong acid as an anion. The strong anions may be exchanged for anions of other organic and inorganic acids and the dyes may also be used as their free bases or double salts. The salts colour tanned cellulose fibres, silks, hair, leather, polyacrylonitrile fibres and fibres of polymers of asymmetrical dicyanethylene. Yellow and orange shades are obtained. Examples are provided of the preparation of the dyes and their use in colouring processes. Specification 844,419 is referred to.