摘要 |
A method of hardening gelatin which uses both a gelatin hardener and a polymer having a repeating unit of the formula (I): <IMAGE> (I) wherein R represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a halogen atom; M represents a hydrogen atom, an alkali metal atom, an alkali earth metal atom, or an organic base; X represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group, an alkylamino group, or a halogen atom; m represents 0, 1 or 2; and n represents 1 or 2. |