New chromium and cobalt complexes of monoazo dyestuffs of the benzene-azo-pyrazolone series and their manufacture and use

摘要

The invention comprises 1,2-chromium or -cobalt complexes of monoazo dyes which contain at least one sulphonic acid group and are of formula FORM:0925997/IV(a)/1 wherein R is a benzene residue which is free from sulphonic and carboxylic acid groups and contains the -OH group in o-position to the azo group and Pz is the residue of a 1-aryl-5-pyrazolone bound to the azo group in the 4-position and containing in the 3-position a methyl or carboxyl group and of which the aryl residue contains two 6-membered rings and at least one sulphonic acid group. The complexes are prepared by treating a dye of the above formula or containing an o-alkoxy or -acyloxy group instead of hydroxy in R with a chromium- or cobalt-yielding agent under conditions such that a 1:2-complex is obtained. Conventional metallization procedures are used. The dyes may be used to colour silk, leather, polyamides, polyurethanes and particularly wool in yellow, red, brown and bordeaux shades. Examples are given. Specification 424,625 is referred to.