Patent ID: 8182977

Claim:
A polymer comprising: a repeating unit (a-1) shown by a following formula (a-1); a repeating unit (a-2) shown by a following formula (a-2); and a GPC weight average molecular weight of about 1000 to about 100,000, wherein R 0 represents an alkyl group having 1 to 5 carbon atoms in which at least one hydrogen atom is substituted by a hydroxyl group, and R 1 represents a hydrogen atom, a methyl group, or a trifluoromethyl group, wherein R 1 represents a hydrogen atom, a methyl group, or a trifluoromethyl group, R 2 represents an alkyl group having 1 to 4 carbon atoms, and R 3 represents an alkyl group having 1 to 4 carbon atoms, a substituted or unsubstituted monovalent cyclic hydrocarbon group having 4 to 20 carbon atoms, or a divalent cyclic hydrocarbon group having 4 to 20 carbon atoms formed by R 3 and R 3 bonding to each other together with a carbon atom to which the R 3 and R 3 bond.