OPTICAL MOLDING AND OPTICAL INFORMATION RECORDING MEDIUM

摘要

PURPOSE:To minimize the generation of white spots and to obtain the optical molding having high reliability by specifying the quantity of the terminal hydroxyl group and the quantity of residual trace sodium in a polycarbonate resin to certain reference values or below. CONSTITUTION:The optical molding is constituted of the polycarbonate resin in which the content of the terminal hydroxyl group is <=0.3mol% per repeating unit of polymerization. This molding is further preferably constituted of the polycarbonate resin in which the content of the terminal hydroxyl group is <=0.3mol% per repeating unit of the polymerization and the quantity of the residual sodium is <=1ppm and which contains 0.002 to 0.5wt.% of 14 to 30C fatty acid monoglyceride. The polycarbonate resin having 10,000 to 40,000 viscosity average mol. wt. is used. The generation of the white spots is sufficiently suppressed in this way and the this optical molding is usable for not only optical disks but optical cards, optical fibers, optical lenses as well.