Patent ID: 7361295
Filing Date: 2008-04-22
Classification: B29C,B29D,B29K,C08J

Abstract:
1. A process for solvent casting which comprises casting a dope from a casting die onto a casting support, drying the cast dope on the casting support to form a film, stripping off the film from the casting support, and further drying the film while conveying the film with carrying it at both side edges of the film by a tenter, wherein dry thickness (X μm) of the both side edges and mean dry thickness (T μm) of product portion of the film have following relationship: in the case that the tenter is a pin tenter, in the range of T≦60, in the range of 60<T≦120, in the range of 120<T, in the case that the tenter is a clip tenter, in the range of T≦40, in the range of 40<T≦120, in the range of T>120, wherein the temperature of said tenter is lower than the boiling point of residual solvent in the film by 2-50° C.; wherein said tenter is forced to be cooled by a cooling means; and wherein the temperature of the film at both side edges carried by the tenter is lower than the boiling point of residual solvent by 2-50° C., but higher than dew-point of atmospheric gas by 2-50° C.