| 摘要 |
PROBLEM TO BE SOLVED: To prevent a distortion such as fringe curling of a film in a method for solvent casting. SOLUTION: A dope comprising a polymer such as a cellulose acetate, dissolved using methylene chloride as a main solvent, is casted from a casting die onto a band 12, dried to get self-sustainable. Concerning rollers 15 to 18 located in a pre-entry area to a tenter and touching a film 14 within 10 seconds after its strip off from the band, temperature around them is controlled between T and T+30°C provided that T°C is the boiling point of the main solvent for the dope. Also, all the rollers 15 to 18 are arranged to touch the film 14 on a reverse side to the band 12. The fringe curling of the film 14 due to rapid solvent evaporation after stripping from the band 12 does not occur and a conveying stability can be maintained. COPYRIGHT: (C)2003,JPO |
