| 摘要 |
PURPOSE:To ensure that cooling effects are improved and thereby, high-quality film can be molded at high speed for a long time using an inflation molding process by blowing a cooling air in a direction which is vertical with the extrusion direction of molten resin and a forward direction sequentially so as to cool the molten resin. CONSTITUTION:A thermal plastic molten resin 7 is extruded in an annular form from an annular die 1 connected to an extrusion machine to mold a valve. Then after the passage of the molten resin 7 past an inflation start point 2, the resin 7 is inflated to become deformed, and is allowed to coagulate into an annular film in a frost line 4. This annular film is taken up using a pinch roll 3. In this case, cooling air is blown to the molten resin 7 using a cooling device 5. That is, the first cooling air 12 is blown in a vertical direction with the extrusion direction 10 of the molten resin 7. Next, the second cooling air 12 is blown to the downstream side of an inflation molding process in the extrusion direction 10 of the molten resin 7. Thus it is possible to mold high-quality film at high speed for a long time using an inflation molding technique. |
