| 摘要 |
PROBLEM TO BE SOLVED: To prevent an impurity contained in a dope from depositing on a cooling drum. SOLUTION: A swelling fluid 25 is prepared by dissolving TAC with a solvent inside a dissolution tank 12. Next, the swelling fluid 25 is sent to a heating device 15 by a pump 26 and heated, and the dope 27 is obtained by increasing the solubility of a solid content of the swelling fluid 25. Then the dope 27 in a hot state is cooled by a cooling device 16, and the temperature of the dope 27 is reduced to the level close to the surface temperature of a support by cooling. The support is used for casting the dope 27 and installed inside film manufacturing facilities 40. Thus the deposition of the impurity contained in the dope 27 is achieved. Since the impurity contains a hemicellulose etc, the dope 27 is filtered by a filtration device 17 to remove the impurity. In the above procedures, the impurity of the dope 27 deposited at the level close to the surface temperature of a cooling drum, is removed inside dope manufacturing facilities 10 prior to casting the dope 27. Consequently, the deposition of the impurity on the cooling drum can be inhibited. COPYRIGHT: (C)2008,JPO&INPIT |
