| 摘要 |
PURPOSE:An economically producible porous film having extremely improved tear strength, improved permeability and uniform qualities, obtained by forming heat-treated parts. CONSTITUTION:A thermoplastic oriented porous film having heat-treated parts. The film is obtained by blending a thermoplastic resin with a filler and an olefin polymer or softener to give a composition, molding the composition in a molten state to give a film, stretching or biaxially orientating the film to form an orientated porous film and then making heat-treated parts. The area of the heat-treated part is >=5% the whole area. A polyethylene resin, preferably linear low-density polyethylene resin, polypropylene resin, polyethylene terephthalate resin, etc., are used as the thermoplastic resin and 100pts.wt. of the resin is blended with 100-300pts.wt. filler and 5-100pts.wt. olefin polymer or softener. |
