| abstract |
The present invention relates to a non-aqueous secondary battery comprising a porous substrate and an adhesive porous layer formed on at least one surface of the porous substrate and comprising an adhesive porous layer containing a polyvinylidene fluoride resin A and a polyvinylidene fluoride resin B A battery separator is provided. (1) a vinylidene fluoride homopolymer having a weight average molecular weight of 600,000 to 2,500,000, a vinylidene fluoride homopolymer having a constitutional unit derived from vinylidene fluoride and a constitutional unit derived from hexafluoropropylene and having a constitutional unit derived from hexafluoropropylene (2) a vinylidene fluoride resin selected from the group consisting of a vinylidene fluoride copolymer having a content of constituent units of 1.5 mol% or less and a weight average molecular weight of 600,000 to 250,000, and A polyvinylidene fluoride resin B containing a constituent unit derived from hexafluoropropylene and having a content of a constituent unit derived from hexafluoropropylene relative to the entire constituent unit exceeding 1.5 mol% |