Polyurethane dispersions

Abstract

The invention relates to aqueous polyurethane dispersions with an acid number of 5 to 60 mg KOH/g of the polyurethane solid, a hydroxyl group content of 0.25 to 6.5% by weight and 2 to 25% by weight of urethane groups (calculated as —NH—CO—O—) based on the polyurethane solid. The inventive dispersions are characterized in that the polyurethanes are the reaction products of a) 10 to 80% by weight of at least one dimer diol, b) 10 to 80% by weight of at least one dimer diol carboxylic acid and/or dimer diol ether, c) 1 to 10% by weight of at least one acidic component that consists of I) hydroxycarboxylic acids, ii) aminocarboxylic acids, iii) aminosulfonic acids and iv) hydroxysulfonic acids, d) 0 to 20% by weight of a low-molecular component that consists of compounds of the molecular weight range of 60 to 300 and that carry at least two hydroxyl and/or amino groups, e) 0 to 20% by weight of at least one hydrophilic, mono- or polyvalent alcohol of the molecular weight range of 350 to 3,000 that carries ethylene oxide moieties, and f) 5 to 40% by weight of an isocyanate component. The reaction products are at least partially base-neutralized and the percentages indicated add up to 100.

Dependencies are inferred from the claim text.