| abstract |
There are provided a porous film comprising a polymer composition comprising ( a ) a polymer having C=C double bond and an aliphatic ring having 5 to 10 carbon atoms in a main chain thereof; and ( b ) another resin; a porous film, wherein all or a part of C=C double bond in the (a) polymer is disappeared; and a porous film, wherein the ( a ) polymer and the (b) resin are cross-linked therebetween. The porous film has appropriate porosity, air permeability and puncture strength, and is especially excellent in latent heat resistance or heat resistance. Further, there are provided a process for producing the porous film; a separator for a battery comprising the porous film; and a battery comprising the separator. |