| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for stably manufacturing a uniaxially oriented polyester film capable of being used in a state bonded to the constituent member or the like of a large-sized liquid crystal display device unnecessary to peel at the time of inspection, having stable optical characteristics in an axial direction, having good inspection properties, and suitable as a substrate of a surface protective film and a release film. SOLUTION: The method for manufacturing the uniaxially oriented polyester film includes a process for laterally stretching a polyester film in the stretching zone in a tenter, and a process for thermally fixing the laterally stretched polyester film in a thermal fixing zone. The temperature of the stretching zone is (Tg+70)-(Tg+10) deg.C, the temperature of the thermal fixing zone is (Tg+130)-(Tg+30) deg.C (herein, Tg is the glass transition temperature of the polyester film), the temperature of the stretching zone is lower than that of the thermal fixing zone, the temperature difference between them is 20-60 deg.C, and the speeds of the respective rolls present between the lateral stretching process and a product take-up machine is 99.0-100.0% with respect to the speed in the flow direction of the film at the time of lateral stretching. |
