Composition for optical material

A composition for an optical material consisting essentially of:

• 5 to 80% of a polyallyl carbonate of a linear or branched alkylene glycol represented by the following general formula (II)
• (CH.sub.2 =CHCH.sub.2 -OCOO).sub.y -Y-OCOO-CH.sub.2 CH=CH.sub.2(II)
• wherein y is an integer of 1 to 10 and Y represents an organic residue derived from a C.sub.2 to C.sub.12 polyol having y+1 hydroxyl groups,
• 20 to 70 wt % of an allyl ester oligomer having allyl ester groups at the terminal ends thereof and recurring units represented by the following general formula (I) ##STR3## wherein x is an integer cf 1 to 10, A represents an organic residue represented by one of the following structures 1 to 6, ##STR4## and Z is an organic residue of a C.sub.2 to C.sub.30 polyol having x+1 hydroxyl groups;
• and 0 to 50 wt % of at least one monomer selected from the group consisting of diallyl 1,2-, 1,3- and 1,4-cyclohexanedicarboxylates, diallyl 4-cyclohexene-1,2-dicarboxylate, diallyl methyl-4-cyclohexene-1,2-dicarboxylate, diallyl bicyclo-2-heptane-5,6-dicarboxylate, diallyl bicyclo-heptane-2,3-dicarboxylate, alkyl acrylate, alkyl methacrylate, diallyl maleate and dialkyl fumarate.