| 摘要 |
PURPOSE:To make it possible to cut easily and straightly a film used for packaging materials, etc., by hand by rolling uniaxially a crystalline thermoplastic resin film and forming thereby the film in such a way that the ratio of the degree of orientation in the perpendicular direction to that in the transverse direction exhibits a specified value. CONSTITUTION:A polyolefin resin such as high/middle/low density polyethylenes and polypropylenes, a polyamide resin or a polyester resin is used as a crystalline thermoplastic resin film. A straightly cutting film having a ratio of the degree of orientation in the perpendicular direction to that in the transverse direction of at least 5 measured by means of infrared dichroism is obtd. by preheating this resin film in a temp. range which is at most the rolling temp. to 50 deg.C lower and rolling uniaxially at a rolling temp. which is in the range of this thermoplastic resin to 70 deg.C lower. In addition, this film exhibits a straight line cutting properties of 0.8-1.2 expressed by an equation of the width at the central part when it reaches the position of the straight line cutting properties= H (300mm)/the width D (20mm) when a test is started. |
