| abstract |
A battery separator comprising a sheet material containing a polyvinyl alcohol cross-linked by a cross-linking group of the general formula (I):n n wherein A represents a group of -CH=CH-R₁ orn n R₁ represents an optionally substituted quaternary nitrogen-containing aromatic heterocyclic group, R₂ and R₃ independently represent a hydrogen atom or alkoxy group having 1 to 4 carbon atoms, m is o or 1, and n is an integer of 1 to 6, is disclosed. n The separator exhibits a good resistance to electrolyte, electrolyte holding rate, and resistant to short-circuits. |