| abstract |
A laminated porous membrane characterized by comprising, as the essentials, both a polyolefin porous membrane in which protrusions that are made of a polyolefin and satisfy the relationships 5[mu]m<=W<=50[mu]m (wherein W is the size of each protrusion) and 0.5[mu]m<=H (wherein H is the height of each protrusion) are irregularly scattered on one surface thereof at a density of 3 to 200 protrusions /cm2, and a modifying porous layer which is laminated on the protrusions-bearing surface of the polyolefin porous membrane and which contains a binder having a tensile strength of 5N/mm2 or more and inorganic particles. Thus, a laminated porous membrane which exhibits an extremely high peel strength between the polyolefin porous membrane and the modifying porous layer and is suitable for high-speed fabrication and a laminated porous membrane which is to be used as a separator for a battery are provided. |