MULTILAYER POROUS MEMBRANE AND METHOD FOR PRODUCING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a multilayer porous membrane which has both high safety and high practicality particularly as a separator for non-aqueous electrolyte batteries. SOLUTION: The multilayer porous membrane includes a porous layer containing an inorganic filler and a resin binder on at least one side of a polyolefin resin porous membrane. The porous layer satisfies the following conditions (A)-(C) at the same time. (A) The average particle diameter of the inorganic filler is not less than 0.1μm and not more than 3.0μm. (B) The ratio of the resin binder relative to the total of the inorganic filler and the resin binder is not less than 0.5% and not more than 8% by volume. (C) The ratio of the thickness of the porous layer relative to the total thickness of the multilayer porous membrane is not less than 15% and not more than 50%. COPYRIGHT: (C)2008,JPO&INPIT