Curable polyurethane polymer

The present invention relates to a curable polyurethane polymer which DOLLAR AA) 10 to 60 wt .-% of at least one hydroxyl-containing prepolymer having at least one =, ethylenically unsaturated double bond, DOLLAR AB) from 0.1 to 30 wt .-% of at least one compound having at least one isocyanate-reactive hydroxyl and / or primary or secondary amino group and additionally at least one polar functional group per molecule, DOLLAR AC) from 0.1 to 30 wt .-% of at least one compound selected from diamines, polyamines and mixtures thereof, DOLLAR AD) 0 to 10 wt .-% of at least one other of a), B), C) and e) different compound having at least two isocyanate-reactive groups, wherein hydroxyl groups and mixtures of hydroxyl groups with primary and / or secondary amino groups is, DOLLAR AE) 0 to 20 wt .-% of at least one compound having one isocyanate-reactive group, DOLLAR AF) 10 to 65 wt .-%, based on the total weight of components a) to F), at least one compound with at least two isocyanate groups, DOLLAR a in copolymerized form, and the salts thereof, which is characterized in that the ratio of isocyanate group equivalents of component F) to equivalents of isocyanate-reactive groups of components a) to e) in a range of 0, 4: 1 to 0.9: 1, polymer dispersions comprising at least one such polymer and the use thereof.