| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polycarbonate resin composition excellent in strength and transferability on injection molding and used for optical disk substrates by including a prescribed amount of a specific low mol.wt. polymer. SOLUTION: This polycarbonate resin composition contains 3.5-8 wt.% of a low mol.wt. polymer comprising repeating units represented by the formula [X is a 1-4C alkylene, a 2-3C alkylidene, O, S, CO, SO, SO2 ; (n) is 1-4] (cases containing 14-30C aliphatic acid monoglyceride in amounts of 0.06-0.1 wt.% are excluded). The optical disk substrate is an optical disk substrate or DVD substrate comprising a molded substrate having a thickness of <=1 mm, preferably <=0.6 mm, or the laminate of the two molded substrates. The substrate is obtained by injection-molding the resin composition at a resin temperature of >=350 deg.C and at a mold temperature of >=100 deg.C. The viscosity-average mol.wt. of the polycarbonate resin is preferably 10,000-25,000. |
