GB1420258A - Process for preparing coloured polyurethane leather process for preparing coloured polyurethane - Google Patents

Abstract

1420258 Coated products HODOGAYA CHEMICAL CO LTD 5 July 1973 [5 July 1972 17 Aug 1972] 32154/73 Heading B2E [Also in Divisions C3, C4 and C5] Coloured polyurethane leather is prepared by reacting a polyisocyanate with an active hydrogen-containing compound and coating the resulting polyurethane on a sheet of polyurethane, polyvinyl chloride, nylon, cloth or non- woven fabric, these being incorporated before or during the addition reaction a 2:1 type metal complex dye which has an isocyanato-reactive amino group, alkylamino group or alcoholic hydroxyl group which has the formula wherein A and A' each represents an optionally substituted phenylene group in which the ortho position with respect to the bond to the N=N group, B and B' each represents an optionally substituted aromatic homocyclic or heterocyclic group in which the bond to the D or D' group is in an adjacent position with respect to the bond to the N=N group, Z and Z' each represent -O or -COO-, D and D' each represents -O-, -NH- or -N(alkyl)-, M represents a chromidal or cobalt atom, [K]<SP>+</SP> represents a hydrogen, sodium or ammonium ion or an ion derived from a primary, secondary or tertiary amine, n represents an integer for 1 to 4 and Y represents -N(R 1 )(R 2 ), -(CH 2 ) n2 -OH, -X 3 -(CH 2 ) n2 -N(R 1 )(R 2 ), -X 3 -(CH 2 ) n2 -OH, -X 3 -N(R 1 )-(CH 2 ) n2 -N(R 1 )(R 2 ) or -X 3 -N(R 1 )-(CH 2 ) n2 -OH wherein R 1 and R 2 each represents hydrogen, C 1-4 alkyl, an amino or hydroxy substituted C 1-4 alkyl, an N-alkyl-amino or N-hydroxyalkyl-amino substituted C 1-4 alkyl group and can form a heterocyclic 6-membered ring through an amino group, X 3 represents -SO 2 - -NHSO 2 -, -CO- or -NHCO-, and n<SP>2</SP> represents an integer of 1 to 4. Alternative methods of preparing the polyurethane leather comprise (a) first reacting the complex dye with the polyisocyanate which is then reacted with a polyol, or a polyurethane, (b) mixing the complex dye with the polyisocyanate, a polyol or polyurethane and a solvent and coating the resulting solution on a substrate or (c) mixing the complex dye with a polyurethane and a solvent, coating the resulting solution on a substrate and then coating on top of this initial coating a solution of polyisocyanate and polyurethane in a solvent. Numerous complex dyes are disclosed. The active hydrogen-containing compound may be a polyol or a polyurethane, in the latter case the active hydrogen being present on the urethane group.