MULTI-LAYERED POROUS FILM, ELECTRICAL CELL SEPARATOR, AND ELECTRICAL CELL

摘要

A multi-layered porous film in which a porous layer (B) for which a filler (a) and binder resin (b) are essential components is provided to at least one side of a polyolefin porous film (A), the true specific gravity of the filler (a) being less than 2.0 g/cm3. Provided is a multi-layered porous film offering low heat shrinkage and excellent melt-down resistance properties without compromising the properties of insulation performance, ion permeability, light weight, and slip performance normally required for a separator. Also provided is an electrical cell or capacitor of high safety and high weight energy density in which the multi-layered porous film is used as a separator.