| 摘要 |
PROBLEM TO BE SOLVED: To provide a fluid-permeable fine porous material having a novel substrate composition and structure and is suitable for a separator for a secondary battery etc., a filtering medium, a culture medium, a moisture-permeable material, etc. SOLUTION: The fluid-permeable fine porous material made of a thermoplastic resin comprises 50-99 wt.% thermoplastic resin (A) used as a substrate and 1-50 wt.% in total of a pore-forming material (B) and an aperture-forming agent (C) which are mixed and dispersed therein. The porous material is formed by extending a fine porous material-forming precursor composition molded product so that boundaries between the thermoplastic resin (A) used as the substrate and the pore-forming material (B) and the aperture-forming agent (C) are at least partially separated to produce pores (P) and apertures (I). The porous material has a group of large pores (P) having an average pore diameter of 0.5-100μm and a group of smaller apertures (I) having an average aperture diameter of 0.01-30μm on at least part of a porous wall part of the pore (P) and has an air permeability of≤1,000 (sec/100 cc×25μm thickness) and a porosity of 30-90%. COPYRIGHT: (C)2008,JPO&INPIT |
