| 摘要 |
PROBLEM TO BE SOLVED: To provide the even and stabilized surface reforming effect while easily realizing a desirable porous structure at low cost without lowering physical property such as strength or the like by including a specified rate or less of the hydrophilic reforming agent having a specified molecular weight in the thermoplastic resin of the porous base material with internal addition. SOLUTION: One or more kinds of hydrophilic reforming agent such as chelate agent of a triazole group, tetrazole group, substituent hydrazine group, malonamide group and oxalate amide group having 1,000 or less of molecular weight is included at 0.05-5 pts.wt. in relation to 100 pts.wt. of the thermoplastic resin such as high density polyethylene. Excellent surface reforming effect can be obtained by the simple internal addition, and mixing property with the base material resin is improved by including 5 pts.wt. or less of the hydrophilic reforming agent having a low molecular weight, and adverse effect on the porous structure can be prevented. A forming film of a composition essentially composed of these material is drawn for porosity. A separator using this film is appropriate for a battery or a capacitor using the non-aqueous electrolyte hard to be wet. |
