PREVENTING MIGRATION OF PIGMENTS IN DYEING OR PRINTING FIBROUS MATERIALS

1398004 Prevention of migration in pigment dyeing BADISCHE ANILIN-& SODA-FABRIK AG 6 Oct 1972 [7 Oct 1971] 46194/72 Heading D1B [Also in Division C3] Migration of pigments during dyeing and printing process is prevented by adding to the pigment dye liquor or print paste a block copolymer of formula B m -An n -B m in which A is an ethylene oxide unit, B is a 1, 2-propylene oxide unit, n is an integer 30 to 60, m is an integer 10 to 25, the weight ratio of ethylene oxide to propylene oxide preferably being 60:40 to 50:50. A minor proportion by weight of the block copolymer may be replaced by a C 8 to C 12 alkylphenoloxyethylate of MW 500 to 800 or by a polyethylene glycol of MW 300 to 500. The copolymer is added to pigment dye liquors and print pastes in an. amount of 0.3 to 5% by weight based on weight of the liquor or paste.