MANUFACTURING PROCESS OF POLYOLEFIN RESIN FILM

PROBLEM TO BE SOLVED: To provide a manufacturing process of a polyolefin resin film which can be suitably used for producing a film excellent in transparency, in the manufacturing process of the polyolefin resin film which has the steps of forming a cylindrical film melt extruded from the polyolefin resin film from an annular die in an opposite gravity direction and cooling the cylindrical film while drawing the cylindrical film in the antigravitational direction. SOLUTION: The manufacturing process of the polyolefin resin film comprises the steps of forming the cylindrical film by melt-extruding the polyolefin resin from the annular die in the antigravitational direction and cooling the cylindrical film in the antigravitational direction while the cylindrical film is drawing in the antigravitational direction and is characterized by including the steps of bringing a water absorbable material having a width of the gravity direction of 5 mm or more as the water absorbable material containing water from any position of 0-200 mm of a frost line obtained by air cooling in the gravity direction into contact with the outer peripheral surface of the cylindrical film and cooling it. COPYRIGHT: (C)2008,JPO&INPIT