Patent ID: 8071659

Claim:
A process for preparing radiation-curing allophanates having residual monomer contents of less than 0.5% by weight and an NCO content of less than 1% by weight, the process comprising: 1) preparing NCO-group-containing urethanes having radiation-curing groups by reacting: A) one or more compounds containing isocyanate groups, B) one or more hydroxy-functional compounds which contain groups which react, with polymerization, with ethylenically unsaturated compounds on exposure to actinic radiation (radiation-curing groups) and C) optionally further compounds containing NCO-reactive groups; D) optionally in the presence of a catalyst 2) reacting the NCO-group-containing urethanes having radiation-curing groups subsequently, without further addition of compounds containing isocyanate groups, in the presence of: E) zinc octoate and, F) a tertiary amine, the ratio of NCO groups of the compounds from A) to the OH groups of the compounds from B) and, where used, C) being 1.45: 1.0 to 1.1 : 1.0.