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.