POROUS FILM AND SECONDARY CELL ELECTRODE

The invention intends to provide a porous film which is formed on a surface of an electrode used for such as a secondary battery and the like, which has excellent binding property and is capable to contribute for improving a cyclic characteristic of the battery. A porous film according to the present invention comprises water soluble polymer, inorganic filler and water insoluble polymer comprising 0.5 to 40mass% of monomer unit including hydrophilic group selected from the group consisting of carboxylate group, hydroxyl group and sulfonic acid group.