| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a polycarbonate resin with little dimensional change (expansion) by moisture absorption; and to provide a substrate for an optical disk, using the polycarbonate resin. <P>SOLUTION: The polycarbonate resin containing sulfur comprises 95-5mol% structure represented by general formula (1) (wherein, R<SB>1</SB>is a 3-8C alkyl group, a 5-10C cycloalkyl group or a 6-10 aryl group; R<SB>2</SB>is a hydrogen atom or a methyl group) and 5-95mol% structure represented by general formula (2) (wherein, R<SB>3</SB>, R<SB>4</SB>and R<SB>5</SB>are each independently a hydrogen atom or a methyl group; W is a single bond, a 1-12C alkylidene group, a 5-10C cycloalkylidene group, a 7-13C aryl-substituted alkylidene group, a fluorenylidene group or an α, α, α', α'-tetramethylxylidene group), and has ≤0.03% expansion coefficient in saturation in the diameter direction when a disk-shaped molded product is soaked in water at 23°C. The substrate for the optical disk uses the resin. <P>COPYRIGHT: (C)2004,JPO |
