| 摘要 |
PROBLEM TO BE SOLVED: To obtain a TAC (cellulose acylate) film decreasing a displacement of a slow axis. SOLUTION: Dope containing TAC is cast on a casting band. After the dope becomes self-supportable, the dope 46 is peeled as a wet film, and is transferred to a tenter 60. The film is preliminarily heated in the inlet portion 80, and is broadened at a stretching velocity Y (%/min) in the stretching portion 81. After the film is narrowed in the relaxation portion 82, the film 61 is sent out from the tenter 60 while keeping approximately the same width in the exit portion 83. It is possible to prevent the generation of a bowing phenomenon and decrease the displacement of the slow axis by satisfying ¾0.27X+1.01XY-21.2¾<5.0 wherein X is a difference of an amount of a remaining volatile component between the starting position 81a of stretching and the ending position 82b of relaxation 82b. COPYRIGHT: (C)2006,JPO&NCIPI |
