GB822734A - Improvements relating to metallisable monoazo dyestuffs complex heavy metal compounds thereof and their use - Google Patents

Abstract

The invention comprises metallizable monoazo dyes of formula <FORM:0822734/IV(c)/1> wherein A is a benzene radical having the hydroxyl group ortho to -N = N-, B is the radical of a coupling component and X is a hydroxyl or amino group ortho to -N = N-; and complex cobalt or chromium compounds thereof preferably containing one metal atom in complex linkage with two molecules of the dye. The dyes are prepared by coupling a diazotized o - hydroxyamino - benzaldehyde with a coupling component which couples ortho to a hydroxy or amino group. The dyes are preferably free from groups which dissociate acid in neutral water. Specified diazo components are o-hydroxyaminobenzaldehydes with or without nitro, alkyl, alkoxy, sulphonic acid, acylamino or halogen substituents. Specified coupling components are acylacetic acid arylamides, 5-pyrazolones, 2:4 - dihydroxyquinolines, p-alkylphenols, acylaminonaphthols and naphthols, which may be substituted by sulphonic acid, acylamino, halogen, alkyl, alkoxy and sulphonamide groups. Metallization is carried out in known manner and mixtures of the dyes with other metallizable dyes or colourless organic complex formers may be metallized. The dyes and metal complexes are used to dye wool, silk and synthetic polypeptide fibres in yellow, orange, red, brown to grey shades. Reference has been directed by the Comptroller to Specifications 637,404 and 692,073.