摘要 |
The present invention provides polyurethane systems which cure by radiation and thermal action with crosslinking, and use thereof for the production of holographic media. The polyurethane compositions of the invention comprise A) polyisocyanates, B) isocyanate-reactive block copolymers, C) compounds having groups which react on exposure to actinic radiation with ethylenically unsaturated compounds with polymerization, D) optionally free radical stabilizers and E) photoinitiators. |