Patent ID: 7512309

Claim:
A polymer composition comprising 5 to 100% by mass of a unit (A) of a lactone compound represented by a general formula (1) and 0 to 95% by mass of a unit (B) of (meth)acrylate as constitutional units, wherein the unit (A) of lactone compound comprises a unit of an (S) isomer represented by a general formula (2) and a unit of an (R) isomer represented by a general formula (3) at a mass ratio of from 70/30 to 30/70, and wherein the polymer composition has a total light scattering loss of not more than 100 dB/km, wherein, in the formulae (1) to (3), R 1 represents a methyl group, an ethyl group, or a propyl group; and R 2 and R 3 independently represent a hydrogen atom, a C 1-12 alkyl group that may be unsubstituted or substituted with one or more than two fluorine atoms, a phenyl group that may be unsubstituted or substituted with one or more than two alkyl groups, or a cyclohexyl group that may be unsubstituted or substituted with one or more than two fluorine atoms, or alternatively R 2 and R 3 may unite each other to form a 5- or 6-membered ring including the carbon atom to which R 2 and R 3 are bonded, where the 5- or 6-membered ring may be substituted with one or more than two fluorine atoms.