GB439372A - The manufacture of azodyestuffs - Google Patents

Abstract

Azo dyes are made by coupling the diazo compounds of arylenethiazoles of the formula <FORM:0439372/IV/1> in which X=halogen or alkoxy and both benzene nuclei may contain further substituents other than benzene radicles with coupling components suitable for the production of direct cotton dyes. They are capable of forming either in substance or on the fibre copper compounds fast to light. The following dyes are described in examples (1)--(3) 2-(4<1> - amino - 3<1> - methoxyphenyl) - 6 - methylbenzthiazole sulphonic acid --> N - phenyl J acid, N - benzoyl J acid or J acid urea (\ba1/2\be mol); in the latter case the corresponding ethoxy compound or the sulphonic acids of 2-(4<1>-amino-3<1> - ethoxyphenyl) - 4 - methyl - 6 - chlorobenzthiazole may be used as diazo component; the after-coppered shades on cotton are blueishred to blueish-violet; (4) 2 - (3<1> : 5<1> - dichloro - 4<1> - aminophenyl) - 6 - methylbenzthiazole --> 1- or 2-naphthol-3 : 6-disulphonic acid or 8 - chloro - 1 - naphthol - 3 : 6 - disulphonic acid; the copper compound is made by treating with aqueous copper sulphate, caustic soda and glycerine (violet on cotton); (5) 2-(3<1>-chloro-4<1> - aminophenyl) - 6 - methylbenzothiazole - 5<1> - sulpho acid --> N - phenyl J acid or dinaphthyl J acid (1 mol.) and their copper compounds; sulphonic acids of 2-(4<1>-amino-3<1>-chlorophenyl)-4-methoxybenzothiazole may also be used as diazo component. Specifications 4756/93, 1062/94, [both in Class 2], 25029/13, 6644/14, 185,880, 195,649, and 310,354, [all in Class 2 (iii)], are referred to. Aminophenylbenzthiazoles of the above formula are made by condensing a 4-nitro-3-halogen- or 3-alkoxy-aryl carboxylic acid chloride with an aminoaryl-o-mercaptan and reducing the nitro compound. Further substituents, e.g. the sulphonic acid group may be introduced into both the nitro and amino compound.