Synthetic polyamide fibres colored with acid azobenzene dyestuffs, containing a N-alkyl (or substituted alkyl)-n-sulphophenoxyalkylamino radical in the para position to the azo linkage

摘要

Polyamide fibres are colored with dyestuffs of the formula: (I) wherein A represents the residue of a carbocyclic diazotisable amine, R represents an alkyl group, U represents a linear or branched alkylene group of 1 to 5 carbon atoms, V represents an arylene group, and A, B, R and V are unsubstituted or substituted with non-water-solubilizing substituents, and a process for their preparation which comprises diazotising an amine of the formula: