| 摘要 |
<p>A radiation curable composition for molding by polymerization in dies comprising, (A) a compound having at least one (meth)acrylate group and (B) a photopolymerization initiator being an oligomer having a molecular weight of about 300 to about 9000 and comprising on average more than 1.5 (α-ketone, β-hydroxyldialkylethylbenzyl groups). Composition wherein the photoinitiator has a group represented by formula (I), wherein R?1 and R2¿ are alkyl groups having 1 to 5 carbon atoms and n is a number of 2 to 50. The composition exhibits a high curing rate and produces molded products with a high transparency, excellent resistance to coloration upon exposure to light, and superior dimensional precision.</p> |
