GB1120411A - Heterogeneous cobalt complex dyes, their production and use - Google Patents

Abstract

Heterogeneous cobalt complex dyes are prepared by treating a mixture of azo compounds containing groups capable of metal complex formation in substance or on the fibre with a cobalt-yielding agent at least one of the azo compounds being of the formula <FORM:1120411/C4-C5/1> in which the -SO3H group is in one of the 31, 41 or 51 positions and at least one other azo compound being of the formula <FORM:1120411/C4-C5/2> in which R is hydrogen, nitro, chlorine, bromine, low (C1-C4) molecular alkyl or alkoxy group, Y is -OH, -NH2 or -NHX, X is an aryl radical which may be substituted, Z is H, -CONH2 or -CONHX in such a manner that a heterogeneous cobalt complex dye is formed in which less than two cobalt atoms are bound with two azo compounds. The dyes give violet-blue shades on wool, leather, silk and polyamide materials.ALSO:In dyeing Example C a lacquer solution is prepared with 20 parts of vinyl chloride-vinyl acetate copolymer, 70 parts of methyl ethyl ketone and 10 parts ethylene glycol and 1/2 part of the cobalt complex dye as produced in Example 1, the whole being diluted with 25 parts of a methyl ethyl ketone-cyclohexanone mixture. This lacquer is then cast on aluminium foil and air dried, a violet-blue shade being obtained.ALSO:In dyeing Example A wool and nylon are dyed at the boil with a heterogenous cobalt complex prepared as in Example 1. A violet-blue shade is obtained. Dyes may also be formed on the fibre in situ.