PREPARATION OF SINGLE SURFACE MAT POLYCARBONATE FILM

• Main Authors: SUGIMURA YOSHIHIRO, TANAKA TATSU
• Format: Patent
• Language: English
• Published: 17.03.1989
• Subjects: AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; PERFORMING OPERATIONS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDEDFOR; SHAPING OR JOINING OF PLASTICS; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PURPOSE:To obtain a single surface mat polycarbonate film, by pressing polycarbonate extruded under melting to a matted cooling roll, whose surface roughness in the directions parallel and vertical to the surface thereof is specific, under specific line pressure by a guide roll through a release film having heat resistance and a smooth surface while setting the temp. of polycarbonate to a specific value. CONSTITUTION:The molten polycarbonate 3 extruded from an extrusion die 4 is guided between a matted cooling roll 1 and a guide roll 2 within a resin temp. range of 170-200 deg.C and extruded under line pressure of 1-5kg/cm by the guide roll 2 through a release film having a smooth surface such as a heat resistant PET film. The molten polycarbonate on the side of the guide roll 2 receives pressure in a semi-molten state to erase die lines and the mirror surface of the surface smooth film is transferred to said polycarbonate. The molten polycarbonate brought into contact with the matted cooling roll 1 receives the transfer of a mat surface to be cooled. By this method, a good single surface mat polycarbonate film can be obtained.