MANUFACTURE OF POLYCARBONATE RESIN MOLDING MATERIAL FOR DISC BODY

• Main Authors: SHIBATA AKIYOSHI, TANIYAMA SUSUMU, KONDOU SHIGEO
• Format: Patent
• Language: English
• Published: 20.09.1985
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; MAKING GRANULES OR PREFORMS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; PREPARATION OR PRETREATMENT OF THE MATERIAL TO BESHAPED; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIALCONTAINING PLASTICS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE, IN GENERAL

PURPOSE:To obtain a transparent polycarbonate resin molding material for a disc excellent in the optical characteristic by melt extruding a polycarbonate resin powder in a specified air current to pelletize. CONSTITUTION:A polycarbonate resin powder is fed into a hopper of a screw extruder with a vent feeding dry nitrogen continuously into the hopper of the extruder and melt extruded to pelletize. A pellet which generates few dirt-like material insoluble in methylene chloride is obtained by the melt processing in the current of the nitrogen even in the presence of a small wire mesh piece, yet colored in the resin. After dried, the pellet is fed into a molding machine hopper into which is fed the dry nitrogen and molded to obtain a transparent polycarbonate disc body.