Mixed chromiferous complex derived from two different aryl-azo-pyrazolone dyestuff

Abstract

Chromiferous complex dyestuff of the formula: ##STR1## in which A represents a hydrogen atom, an unsubstituted phenyl group or a phenyl group substituted by one or two halogen atoms or alkyl groups containing 1 to 4 carbon atoms and the nucleus B is unsubstituted or substituted by one or two chlorine atoms; salts of such dyestuff; process for the preparation of such a dyestuff which comprises reacting in equimolecular proportions the 1/1 chromiferous complex of a monoazo dyestuff of the formula: ##STR2## and a monoazo dyestuff of the formula: ##STR3## or, conversely, the 1/1 chromiferous complex of a monoazo dyestuff of formula (III) and a monoazo dyestuff of formula (II) wherein A and B have the meanings given above; process for the coloration or dyeing in bulk of a synthetic polyamide in which the coloring agent is a dyestuff of the formula given above or a salt thereof and materials and articles of synthetic polyamide dyed or colored in bulk by means of chromiferous complex of the formula given above or a salt thereof.

Dependencies are inferred from the claim text.