| 摘要 |
PROBLEM TO BE SOLVED: To effectively control the deterioration of a polycarbonate resin and to maintain high reliability for a long time by composing an optical disk substrate with a polycarbonate resin where a relative fluorescence intensity for a reference substance is equal to or less than a specific value when fluorescence spectrum is measured. SOLUTION: In a polycarbonate resin, a relative fluorescence intensity at 465 nm for a reference substance needs to be suppressed to 4×10-3 or less. For obtaining a polycarbonate resin with a relative fluorescence intensity of 4×10-3 or less, an ester exchange catalyst and its amount are preferably prescribed and is preferably deactivated by a sulfone acid compound, the ratio where the molecular end of the polycarbonate resin occupies for the entire molecular end of a hydroxy group is preferably prescribed, and the molecular end of the polycarbonate resin is preferably prescribed. The molecular weight of the polycarbonate resin is preferably 10,000-22,000 in terms of viscosity average molecular weight. |
