GB973228A - New copper complex reactive disazo dyestuffs - Google Patents

Abstract

The invention comprises copper complexes of disazo compounds of formula A1-N=N-B-N=N-A2 wherein B is a radical of the resorcinol or 1,3-dihydroxynaphthalene series having the azo groups in ortho position to the hydroxy-groups. A1 and A2 are aromatic radicals each having a metallizable group in ortho position to the azo group at least one of A1 and A2 having a reactive acylamino group (i.e. a group of formula -N(R)-Z wherein R is a H atom or a C1-C6 alkyl group and Z is an acyl radical which contains a group capable of reaction with the hydroxyl groups of cellulose with formation of a covalent bond between the dye molecule and the fibre molecule. The dyes are prepared by treating the copper complexes of the corresponding amino-disazo dyes with the halide or anhydride of an acid containing a reactive group as defined above. Specified acids include acrylic, chloroacrylic, propiolic, maleic, chloromaleic, chloroacetic, b -chloro- or -bromopropionic and a :b - dichloropropionic acids and in particular halo-triazines and -pyrimidines. The dyes may be used to colour wool and leather from an acid to weakly alkaline bath or cellulose fibres in the presence of an acid-binding agent in brown shades. Examples are given.