New water-soluble monoazo dyestuffs containing ternary sulphonium salt groups

摘要

The invention comprises water-soluble monoazo dyes of formula A-N=N-B wherein A is the residue of a diazo component and B is the residue of a carbocyclic or heterocyclic coupling component linked to -N=N-via a nuclear carbon atom, provided that A and/or B contain at least one ternary sulphonium salt group connected to a carbon atom of an aromatic nucleus of either A or B through an intervening divalent linking radical which does not contain a nitrogen atom and both A and B are devoid of sulphonic or carboxylic acid groups. The dyes are prepared (a) by diazotization and coupling using suitable components; (b) by alkylating a dyestuff of the above formula but which contains a thioether group instead of a sulphonium salt group and (c) by treating with a thioether a dyestuff of the above formula but which contains a halogen atom instead of a sulphonium salt group. The dyes may be used to colour textile materials comprising polymers and copolymers of acrylonitrile and dicyanoethylene in yellow to rubine shades. In examples: (1) the monoazo dye 3-bromo-4-aminophenacyl chloride--N: N-di(b -hydroxyethyl)-m-toluidine is treated with thiodiglycol to give 4[41-(di-b -hydroxyethylamino) -21-methylphenylazo]-3-bro mophenacyl di-b -(hydroxyethyl) sulphonium chloride; (2) the monoazo dye b -(ethylthio)ethyl 4-aminobenzoate--p-cresol is treated with methyl p-toluenesulphonate to give ethyl methyl b -[4(21-hydroxy-51 - methylphenylazo)-benzoyloxy]ethyl sulphonium p-toluenesulphonate; (3) the monoazo dye 4-aminophenacyl di-(b -hydroxyethyl)sulphonium chloride--N-b -hydroxyethyl-a -naphthylamine is prepared. Further examples are described.