Patent ID: 9252412
Filing Date: 2016-02-02
CPC Classification: B32B,H01M,Y02E,Y10T

Claim Text:
1. A multilayer porous film, comprising: a polyolefin-based resin porous film, and a coating layer comprising a filler and a resin binder on at least one surface of the polyolefin-based resin porous film, wherein the filler has an average particle size from 0.2-1.5 μm and comprises particles with particles sizes of less than 0.2 μm and particles with particles sizes of 1.0 μm or more, wherein the particles with particle sizes of less than 0.2 μm (D wherein a specific surface area of the filler is 5 m wherein the multilayer porous film satisfies a condition (1): condition (1): after the multilayer porous film is cut to a size of 50 mm ×50 mm and is stuck on paper in a state where the coating layer faces upward, a column-shaped weight having a diameter of 40 mm and a weight of 700 g and covered with a cotton cloth on an entire bottom surface thereof is placed on the coating layer, and the weight is rotated at a rotational speed of 50 rpm for 10 minutes to rub the surface of the coating layer, observation of the surface of the coating layer shows that the coating layer has a missing portion with an area of less than 10% of a contact area of the weight.