| 摘要 |
PROBLEM TO BE SOLVED: To prevent the formation of the surface defect of a roll by preventing the discharge to a cooling roll at the time of generation of air bubbles in a molten sheet inevitable when a moltn polymer sheet is brought into close contact with the cooling roll by the application of static electricity. SOLUTION: In a molding apparatus for molding a molten polymer sheet extruded from a cap by bringing the molten polymer sheet into close contact with a cooling roll by electrostatic force to cool the same, an earth electrode is provided at the position holding the molten polymer sheet corresponding to a static electricity applying electrode and the value of a current flowing to the earth electrode is monitored. This molding apparatus is used to bring the molten polymer sheet into close contact with the cooling roll and, when a defect such as air bubbles is generated in the molten polymer sheet, the value of the current flowing to the grounding electrode is monitored before the discharge to the cooling roll is generated to stop the application of static electricity.
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