| abstract |
A separator for nonaqueous secondary batteries, which is provided with: a porous base; and an adhesive porous layer that is disposed on both surfaces or one surface of the porous base and contains a vinylidene fluoride-hexafluoropropylene binary copolymer having a ratio of a hexafluoropropylene monomer unit of from 5.1% by mass to 6.9% by mass (inclusive) and a weight average molecular weight of from 810,000 to 3,000,000 (inclusive) such that the vinylidene fluoride-hexafluoropropylene binary copolymer accounts for 95% by mass or more of all resins. |