GB859899A - New monoazo dyestuffs derived from benzthiazole - Google Patents

Abstract

The invention comprises water-insoluble dyes of formula: <FORM:0859899/IV (c)/1> where A is a substituted or unsubstituted 1, 4-phenylene or -naphthylene nucleus which is free from sulphonic or carboxylic acid groups, R is H or a lower alkyl radical which may be substituted or an aralkyl radical, R1 is a lower alkyl radical which may be substituted, X is CN or SCN and B may contain substituents other than sulphonic and carboxylic groups, provided that R and R1, when substituted, are free from sulphonic and carboxylic acid groups and that when R is a b - cyanolower alkyl radical R1 is neither a b -cyanonor a b - acyloxylower alkyl radical. Lower alkyl and alkoxy groups contain 1 to 4 carbon atoms. The dyes are made by diazotising appropriate aminobenzothiazoles and coupling with the desired azo components. Specified substituents for A are methyl, methoxy, chlorine, bromine, trifluoromethyl and acetylamino groups. Specified substituents for B are methyl, chlorine and bromine groups. Representative of values specified for R and R1 are: methyl, hydroxybutyl, ethoxyethyl, cyanopropyl, acetoxyethyl, bromoethyl, carbethoxymethyl, methylsulphonylethyl, ethylcarbonylethyl, aminocarbonylethyl, g - chloro -b - hydroxypropyl, b , g - epoxypropyl and b - (4, 6- diamino -s-triazin -2- yl) ethyl groups. R is also specified as a benzyl group. The dyes dye textiles comprising artificial fibres such as cellulose ester fibres e.g. acetate and triacetate, polyamide fibres, e.g. polyhexamethyleneadipamides and polycaprolactams, polyvinyl fibres, e.g. polyacrylonitriles which may be modified, and aromatic polyester fibres e.g. polyethyleneterephthalates. Dispersed dyeing processes are preferred. Orange to greenishblue shades are obtained. Examples are provided of the preparation of the dyes and their use in dyeing processes. In the Provisional Specification A is described as any substituted or unsubstituted benzene or naphthalene nucleus which is free from sulphonic and carboxylic acid groups and R and R1 are H or a substituted or unsubstituted alkyl radical or a cycloalkyl or aralkyl radical. Specifications 440,113 and 787,369 are referred to.