GB842802A - Water-soluble azo or anthraquinone dyestuffs containing methylol groups, a process for their production, and dyeings obtained therewith - Google Patents

Abstract

The invention comprises water-soluble dyes of formula: [D-]-(CH2OH)n wherein D is an azo or anthraquinone dyestuff radical having at least one water-solubilising group and in which hydrogen atoms susceptible to reaction with formaldehyde have been replaced by methylol groups, and n is 1 to 8. They are prepared by reacting a suitable dye or intermediate with formaldehyde in a medium of pH 6 to 11 and if necessary converting the intermediate to an azo or anthraquinone dye. Specified water-solubilising groups are carboxylic and sulphonic acid or acid amide, ureido or sulphone groups. The dyestuffs dye cellulose, wool, silk, leather and synthetic polyamide and polyurethane fibres, preferably in the presence of acids or acid salts, in red, brown, yellow and blue shades. In examples: (1) the following dyes are reacted with formaldehyde in alkaline medium:-3-aminophenol --> 2-amino-5-naphthol-7-sulphonic acid, 1-amino- 4-(41-ureido-orcarbonamido - phenyl)- aminoanthraquinone- 2-sulphonic acid, sulphanilic acid --> 2-ureido-5-naphthol-7-sulphonic acid or 1-ureido-8-naphthol- 3 : 6 -disulphonic acid and sulphanilamide --> 2-ureido -5- naphthol -7- sulphonic acid; (2) the product obtained by reacting phenol with aqueous formaldehyde is coupled with the diazo compound from 1-amino -3 : 4- dichlorobenzene-5- sulphonic acid or anthranilic acid; (3) as in (2) the reaction product of formaldehyde and 3-hydroxyphenylurea is coupled with diazotised sulphanilamide; (4) the dyes sulphanilamide or 4-aminophenylurea --> 2 : 4-dimethylol-phenol are prepared.