Patent ID: 8101108
Filing Date: 2012-01-24
Classification: B29C,C08J,G02B,Y10T

Abstract:
1. A method for producing a cellulose acylate resin film, comprising the step of, melting a cellulose acylate resin in an extruder and extruding the molten cellulose acylate resin to a die, wherein the step of melting is carried out using a tandem extruder having a first-stage extruder and a second-stage extruder connected in tandem, the cellulose acylate resin has an acylate group satisfying the following substitution degree: wherein X is a substitution degree of an acetyl group, and Y is a total substitution degree of a propionyl group, butyryl group, pentanoyl group, and hexanoyl group, wherein a reservoir tank having a heating device is provided between the first-stage extruder and the second-stage extruder to absorb the fluctuation in pressure between the first-stage extruder and the second-stage extruder, and wherein the reservoir tank has a head space part filled with an inert gas.