摘要 |
In a method for manufacturing a polyolefin microporous film, non-uniformity in a film resulting from non-uniform drying during solvent extraction is minimized, high-speed drying and high-speed continuous productivity of the polyolefin microporous film are implemented. In the method for manufacturing a polyolefin microporous film, in which a composition composed of a polyolefin resin and a plasticizer is made into a film form using extrusion, the plasticize is extracted and removed using a solvent, and the film is thereafter dried. After the foregoing extraction and before the drying, the film is brought into close contact with a roll, or its width is mechanically restrained. A liquid (heating medium) having a temperature greater than r equal to the boiling point of the solvent is made to contact the film while the film is in close contact with the roll or while the width is restrained, whereby the film is heated and dried. |