Radiation-hardenable binders based on thio-polyols

Abstract

A radiation-hardenable binder consisting of a reaction product of: (A) 1 gramme equivalent of NCO of a polyisocyanate containing 2 to 3 isocyanate groups per molecule, (B) 0 to 0.7 gramme equivalents of OH of a polyol containing at least 2 OH-groups per molecule, free from organically combined sulphur, (C) 0.01 to 0.7 gramme equivalents of OH of a hydroxyalkyl acrylate containing 2 to 6 carbon atoms in the alkyl group characterized in that the reaction product additionally has incorporated therein: (D) 0.01 to 0.3 gramme equivalents of OH of a polyol containing thio or dithio groups or thio and dithio groups, with at least 2 OH-groups per molecule, the sum of the OH gramme equivalents B to D is from 1 to 1.2, and the content of organically combined sulphur, derived from the thio and dithio groups, is from 0.01 to 10% by weight, based on the binder.

Dependencies are inferred from the claim text.