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 good single surface mat polycarbonate film, by pressing polycarbonate of specific temp. extruded under melting under specific line pressure using a mirror surface guide roll made of heat resistant silicone rubber whose surface roughnesses in the directions parallel and vertical to the surface thereof and surface hardness are specific. CONSTITUTION:The molten polycarbonate 3 extruded from an extrusion die 4 is guided between a matted cooling roll 1 set to a line pressure range of 1-5kg/cm and a mirror surface guide roll 2 made of silicone rubber having surface hardness of 50-80 deg. within a resin temp. range of 170-200 deg.C. The molten polycarbonate on the side of the guide roll 2 receives pressure in a semi-molten state to erase die lines at the time of extrusion and the mirror surface of the guide roll is transferred to said polycarbonate. The molten polycarbonate brought into contact with the matted cooling roll 1 receives the transfer of the mat surface of the cooling roll 1 and cooled. By this method, a good single surface mat polycarbonate film can be obtained.