| 摘要 |
PROBLEM TO BE SOLVED: To obtain a film having desired Re and Rth. SOLUTION: A dope 11 is prepared from CAP, an additive and a solvent and becomes a wet film 74 through a casting process, a drying process and a peeling process. Then, the wet film 74 becomes a film 82 through a tenter drying process or a drying process. In the tenter drying process the wet film 74 is sent to a tenter type dryer 47 and grasped by clips at both side end parts thereof to be fed to a drying zone. During this feed, drying treatment, stretching treatment or relaxation treatment is applied to the wet film 74. The relaxation treatment in the feed direction is applied to the wet film 74 while applying stretching treatment to the wet film 74 in its width direction. If relaxation treatment in the feed direction is performed when the advance degree EP1 of stretching treatment in the width direction of the wet film 74 is below 70%, a film 82 high in retardation ratio (=Re/Rth) can be manufactured. COPYRIGHT: (C)2007,JPO&INPIT |
