| 摘要 |
It is the aim of the present inventors to provide a battery separator with excellent dry-time adhesion, which is a new problem resulting from an expected increase in battery size in the future, and wet-time adhesion, without deterioration in air impermeability. The battery separator is provided with a microporous membrane and a porous layer disposed at least on one side of the microporous membrane, wherein the porous layer includes vinylidene fluoride-hexafluoropropylene copolymer and acrylic resin, the vinylidene fluoride-hexafluoropropylene copolymer includes a monomer unit with a hydrophilic group and 0.3 mole% or more and 3 mole% or less of a hexafluoropropylene monomer unit, and the acrylic resin includes a butylacrylate monomer unit. |
