Patent ID: 6989225

Claim:
A liquid radiation-curable composition that comprises (A) at least one polymerizing organic substance comprising a mixiure of (1) at least one alicyclic epoxide having at least two epoxy groups; and (2) at least one difunctional or higher functional glycidylether of a polyhydric compound; (B) at least one free-radical polymerizing organic substance comprising a mixture of (1) at least one aromatic di(meth)acrylate compound; and (2) optionally, at least one trifunctional or higher functional (meth)acrylate compound; and (C) at least one cationic polymerization initiator; (D) at least one free-radical polymerization initiator; (E) optionally at least one hydroxyl-functional aliphatic compound; and (F) at least one hydroxyl-functional aromatic compound selected from the ground consisting of bisphenol A, bisphenol S, ethoxylated bisphenol A, and ethoxylated bisphenol S; wherein the concentration of hydroxyl groups in the radiation-curable composition is at least about 1.1 equivalent OH groups per kilogram; wherein the concentration of epoxy groups in the radiation-curable composition is at least about 5.5 equivalent epoxy groups per kilogram; and wherein the amount of trifunctional or higher functional (meth)acrylate compound (B)(2) is from 0% to about 3% of the composition and the amount of aromatic di(meth)acrylate compound (B)(1) is at least 10% of the composition.