GB1261350A - Azo dyestuffs - Google Patents

Abstract

1,261,350. Dyeing with polymerizable azo dyes. IMPERIAL CHEMICAL INDUSTRIES Ltd. 16 April, 1969 [17 April, 1968 (2)], Nos. 18113/68 and 18114/68. Heading C3P. [Also in Divisions C2 and D1] Natural, artificial, and synthetic polymeric materials are dyed by treating with a waterinsoluble azo dye containing at least two groups of the formula -Z-Y n -X in which each Y is an alkylene group, Z is a linking group of the class obtained by reacting a hydroxy, primary or secondary amino group or carbonyl group with a group reactive with a hydroxy, primary or secondary amino or carbonyl groups, n is 0 or 1, X is a group of the formula in which R 1 , R 2 and R 3 each independently represents hydrogen or a methyl group, the dyes being free of sulphonic acid groups and subsequently or simultaneously with a polymerization catalyst. Preferably the linking group 2 is -OCO-, -O-, -COO-, or -NRCO-, in which R is hydrogen or an alkyl, cycloalkyl, aryl, heterocyclic or aralkyl group or a substituted derivative of such a group and Y is a methylene group. The polymerization initiator is preferably used as 1-500% by weight of the dyestuff and heat is used to effect polymerization, e.g. dry heat or steam. Substrates dyed included cotton, wool, silk, viscose rayon, di- and tri-cellulose acetate, polyurethanes, polyamides, acrylonitrile polymers and copolymers optionally acid-modified, and aromatic polyesters. Polymerization initiators include hydrogen peroxide, organic peroxy compounds, azobisisobutyronitrile, alkali metal persulphates and redox systems. Reference has been directed by the Comptroller to Specification 1,046,751.