DE2454800

Photopolymerizable compositions consisting essentially of at least one polymerizable ethylenically unsaturated material and a photosensitive catalyst comprising A. FROM 0.5% TO 5% BY WEIGHT BASED ON THE ETHYLENICALLY UNSATURATED MATERIAL OF AT LEAST ONE PHOTOSENSITIZER HAVING THE STRUCTURE OO PARALLEL PARALLEL Ph-C-C=C-C-Ph ¦¦ -A- wherein Ph is phenyl, halogen-substituted phenyl, phenylene or halogen-substituted phenylene and A is a cyclic hydrocarbyl group, a halogen-substituted cyclic hydrocarbyl group or a group of the formula ¦¦ X-N-C-C-N-Y, PARALLEL PARALLEL OO where X and Y each is hydrogen, a hydrocarbyl or a halogen-substituted hydrocarbyl group, and B. FROM 1 TO 5% BY WEIGHT BASED ON THE ETHYLENICALLY UNSATURATED MATERIAL OF A REDUCING AGENT CAPABLE OF REDUCING THE PHOTOSENSITIZER WHEN THE PHOTOSENSITIZER IS IN AN EXCITED STATE.