R1 and R2 are an aromatic group selected from the group consisting of a substituted or unsubstituted phenyl group, naphthyl group, and polyphenyl group and R4 is selected from the group consisting of a substituted or unsubstituted biphenyl group, diphenyl ether group, alkyl group having from 1 to 18 carbon atoms, and cycloaliphatic group having from 3 to 12 carbon atoms, a polycarbonate film formi