Light curing compositions for dental restoration

Claim 1

A light curing paste composition for dental restoration comprising the following five constitutional components: (a) a polymerizable compound containing at least one ethylenically unsaturated double-bond; a photo-polymerization initiator system consisting essentially of: (b) at least one photo-polymerization initiator selected from ketal base compounds expressed in terms of the following general formula (1): ##STR7## wherein X is H, Cl, an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms, A is a six-membered aromatic group, and R is an alkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 9 carbon atoms or a --C n H 2n O) m R' in which n is an integer of 2 to 5, m is an integer of 1 to 5, and R' is an alkyl group having 1 to 5 carbon atoms, in an amount of 0.01 to 5 weight % relative to polymerizable compound (a), and (c) at least one photo-polymerization initiator selected from benzoin alkyl ether base compounds expressed in terms of the following general formula (2): ##STR8## wherein R is an alkyl group, R' is selected from the group consisting of a hydrogen atom, and alkyl group, and a halogen atom, and R" is one or more groups which may optionally be present on the respective rings of that formula, and are selected from the group consisting of an alkyl group, an alkoxy group, a halogen atom and an alkylamino group, in an amount of 0.01 to 5 weight % relative to polymerizable compound (a); (d) a reducing agent other than (c) in an amount of 0.01 to 5 weight % relative to polymerizable compound (a); and (e) a filler.