| 摘要 |
PURPOSE:To prevent a film from slackening and flapping by setting the temp. of air for drying for a specified conveying time from the peeling-off point when a cellulose triacetate film used for a photographic photosensitive material etc., is prepd. by casting a soln. on a substrate. CONSTITUTION:A cellulose triacetate film 3 cast on a rotating drum 6 from a casting die 1 is dried and cooled for solidification on the drum a and is then peeled off at a peeling-off point 4 on the drum 6 as a film 5, which is conveyed by conveying rollers 7(71, 72,...) and is introduced into a tenter conveying zone 11 and is dried from both faces. In such a film-making method as this, when the wt. ratio of an org. solvent in the film peeled off from the drum 5 is 68wt.% or more, the temp. of air for drying is set at 30-80 deg.C during the conveying time from the peeling-off point is at least 20 sec. Drying of the film 5 is performed rapidly thereby to solidify the film 5 and to attempt to stabilize conveying. |
