Patent ID: 7319120

Claim:
A hydrophilic siloxane copolymer prepared by: reacting, in a first step, organopolysiloxane(s) (1) which have at least one silicon-bonded hydrogen atom per molecule, with at least one substantially linear oligomeric or polymeric compound (2) of the formula R 1 -(A-C n H 2n ) m -A 1 -H (I) where R 1 is a monovalent optionally substituted hydrocarbyl radical capable of adding Si—H groups in a hydrosilylation reaction, A is a bivalent polar organic radical selected from the group consisting of —O—, —C(O)—O—, —O—C(O)—, —O—C(O)—O—, —C(O)—NH—, —NH—C(O)—, urethane radicals and urea radicals, A 1 is a bivalent polar organic radical selected from the group consisting of —O—, —NH— and —NR′—, where R′ is a monovalent hydrocarbyl radical of 1 to 18 carbon atoms, n is an integer from 1 to 20, and m is a positive integer; and reacting, in a second step, the resulting H-A 1 -containing intermediate(s) (4) obtained in the first step, with organic compounds (5) which have two or more isocyanate groups per molecule, with the proviso that the water content of the compounds (1) and (2) is lower than 2000 weight ppm based on the total weight of compounds (1) and (2),and wherein the organic compounds (5) having two or more isocyanate groups per molecule are used in amounts of 0.5 to 1.0 mol of isocyanate groups per mol of H-A 1 group in the intermediate(4).