Abstract: A new class of amines is incorporated into photopolymerizable systems employing type I or type II photoinitiators. These amines are trialkylamines having a total of 10 to about 36 carbon atoms in the molecule and wherein at least one alkyl group has a chain length of at least 8 carbon atoms. Preferably, one or two of the alkyl groups are methyl or ethyl or one of each. Short chain amines as defined herein provide synergistic results when used with such trialkylamines.

Abstract: A new class of amines is incorporated into phtopolymerizable systems employing type I or type II photoinitiators. These amines are trialkylamines having a total of 10 to about 36 carbon atoms in the molecule and wherein at least one alkyl group has a chain length of at least 8 carbon atoms. Preferably, one or two of the alkyl groups are methyl or ethyl or one of each. Short chain amines as defined herein provide synergistic results when used with such trialkylamines.

Abstract: Coinitiator systems for photopolymerization of photopolymerizable compounds containing olefinic unsaturation are described. Such systems comprise (A) either a combination of at least one coumarin photoinitiator and at least one coinitiator compound which is a hydrogen atom donating coinitiator or an electron donating coinitiator, or at least one coumarin photoinitiator having in its molecular structure at least one photosensitizing amino group; and (B) at least one compound containing at least one maleimide or maleic anhydride derivative. Photopolymerizable compositions which comprise, in addition to such a coinitiator system, at least one photopolymerizable compound containing olefinic unsaturation are also described.