Patent ID: 8207238

Claim:
A hardenable dental composition comprising: a polymerizable component; and an initiator system comprising at least one electron donor having the following formula: wherein N is nitrogen; R1 is an alkyl group having 1 to 16 carbon atoms, or is CH 2 CH 2 X2; R2, R3, R4, R5, R6, R7, R8 and R9 are independently selected from H or an alkyl group having 1 to 4 carbon atoms, with the proviso that at least one carbon atom at a position alpha to the nitrogen is bonded to at least one hydrogen atom; X1 is selected from CO 2 R10, C(O)R11, C(O)R10, and CONR10R11 and X2 is selected from CN, CO 2 R10, C(O)R11, and C(O)R10, where each R10 and R11 are independently selected from H, alkyl groups having 1 to 6 carbon atoms, aryl groups, and aralkyl groups.