Patent ID: 7223478

Claim:
A matt finished leather coated with an aqueous polyurethane formulation comprising from 10 to 60%, by weight, of at least one polyurethane A, which is composed of a) at least one organic isocyanate having no lateral alkyl groups [monomers I], b) optionally at least one organic isocyanate having at least one lateral alkyl group [monomers II], c) at least one dihydric or polyhydric alcohol having a number average molecular weight of from 400 to 6000 [monomers III], d) at least one dihydric or polyhydric alcohol having a number average molecular weight of from 62 to 399 [monomers IV], e) at least one carboxylic acid having at least one hydroxyl group [monomers V], f) optionally one or more polyamines having at least two >N—H groups [monomers VI], g) optionally one or more compounds having at least one alcoholic OH group and at least one >N—H group [monomers VII] and h) optionally one or more monohydric polyetheralcohols [monomers VIII], with the proviso that the amounts of the incorporated monomers I to VIII are such that the (—OH+>N—H)/NCO equivalent ratios for the incorporated monomers III/monomers I+II are from 0.1 to 0.75, monomers IV/monomers I+II are from 0.2 to 0.8, monomers V/monomers I+II are from 0.05 to 0.5, monomers VI/monomers I+II are from 0 to 0.4, monomers VII/monomers I+II are from 0 to 0.4, monomers VIII/ monomers I+II are from 0 to 0.2, and those for the sum of the monomers III to VIII/monomers (I+II) are from 0.80 to 1.25, the total amount of monomers I and monomers II contains from 50 to 100 mol % of monomers I, and from 50 to 2000 mmol of the carboxyl groups of the incorporated monomers V, per kilogram of polyurethane A, are present in anionic form in the aqueous formulation, and the dispersed polyurethane particles have a particle size from 2–15 μm.