. . . . "yl group having 6 or less carbon atoms or a phenyl group, R3, R4, R5 and R6 may be the same or different and are a hydrogen atom, a halogen atom, an alkyl group having 6 or less carbon atoms or a phenyl group and A is a cyclic hydrocarbon or an organic group having an aromatic group, ???(O???Y)??? is represented by the formula (19) in which R9 and R10 may be the same or different and are a halogen" . .