| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a film having excellent air permeability, uniform orientation, adhesiveness, shielding properties, etc. SOLUTION: This porous film is obtained by melting and forming a composition comprising a polyolefin resin, a filler and a third component to give a film, then drawing the film. The filler comprises at least one kind selected from among calcium carbonate and barium sulfate and a transparent or white inorganic compound having >=1.7 refractive index in the weight ratio of 99/1-50/50. The third component is composed of a side chain-containing hydrocarbon polymer and a hardened castor oil in the weight ratio of 99/1 to 30/70.</p> |
