| 摘要 |
PURPOSE:To permit the stable molding of homogeneous films with uniform section, by a method wherein a heater, capable of setting a temperature profile different widthwisely, is provided near the lip of a die while the amount of resin, extruded out of the lip, is regulated widthwise. CONSTITUTION:A heater 9 for regulating biased thickness is provided widthwise near a die lip 3 and the heater 9 is connected to a controller 11 electrically while the controller 11 is connected electrically to a temperature sensor 10, such as an infrared ray sensor or the like for example, arranged near the die lip 3. Objective temperature profile is inputted into the controller 11 with respect to each blocks of the heater 9. The controller 11 conducts the heater 9 in accordance with said objective temperatures to set the temperature of the heater 9. When the thickness of a film is thin locally, the temperature setting of the heater 9, corresponding to the thin part, is increased to increase the temperature of that part. Then, the flow rate of resin in the die lip 3 near the heater is increased and, as a result, the thickness of the film is increased whereby the film, in which the difference of thickness is small, may be obtained. |
