GB973915A - New basic azo dyes - Google Patents

Abstract

The invention comprises colour salts whose cations have the general formula <FORM:0973915/C4-C5/1> in which R1 and R2 represent hydrogen, substituted or unsubstituted alkyl, cycloalkyl or aralkyl groups and one of the radicals R1 and R2 may also be an aryl group and in which the indazole and indole ring may be further substituted other than with sulphonic acid groups and A1 and A2 are alkyl, cycloalkyl or aralkyl radicals and a process for the preparation thereof which comprises alkylating, aralkylating or cycloalkylating with appropriate agents azo dyes free from sulphonic acid groups of the general formula <FORM:0973915/C4-C5/2> Starting materials for use in the process are obtained by coupling diazotized 3-amino-indazoles with indoles not substituted in the 3-position. The dyes are reacted with such agents as methyl chloride, benzyl chloride, diethyl sulphate, methyl toluene sulphonate. The dyes can be represented by the following structures in resonance <FORM:0973915/C4-C5/3> The colour salts are employed for dyeing mordanted cotton, leather and fibres, yarn and film of cellulose esters and ethers, polyamides, polyurethanes and polyesters and in particular polyacrylonitrile and copolymers containing acrylonitrile in yellow to red shades. Examples are furnished relating to the preparation of the dyes and their use in dyeing polyacrylonitrile fibre and copolymers of acrylonitrile and vinyl chloride.