METHOD FOR PREPARING DOPE, METHOD FOR PRODUCING FILM FROM SOLUTION AND FILM PRODUCT

摘要

PROBLEM TO BE SOLVED: To provide a method for preparing a dope in which homogeneous dope is obtained by suppressing temperature distribution of the dope in the outlet of a heat exchanger. SOLUTION: The method for preparing the dope comprises the following steps. A dichloromethane-based mixed solvent, TAC (cellulose triacetate) and a plasticizer are put in a dissolution tank 12. These components are agitated by an agitating blade 21 to provide a crude solution 22. The crude solution 22 is transferred into a storage tank 23 to provide further agitated crude solution 26. The crude solution 26 is fed to a heat exchanger 31 for heating by a pump 27 and mixed under stirring by a static mixer 32. Multipoint dope temperatures are measured by a temperature-measuring meter 33. Heat transfer conditions of the heat exchanger 31 are controlled based on the temperature distribution of the multipoint dope temperatures. The dope is fed to a heat exchanger 35 for cooling. The dope is cooled to the boiling point or below and then, mixed under stirring by a static mixer 36. When preparation of the dope is carried out, occurrence of the temperature distribution is suppressed to provide the uniform dope 53. COPYRIGHT: (C)2005,JPO&NCIPI