| 摘要 |
PROBLEM TO BE SOLVED: To obtain a polycarbonate resin molding material for optical use capable of keeping high reliability over a long period and improving the productivity of disk base by reducing the content of monofunctional phenols in a polycarbonate resin. SOLUTION: This polycarbonate resin contains <=50 ppm of monofunctional phenol (preferably alkyl-substituted or phenylalkyl-substituted phenols). The polycarbonate resin has a viscosity-average molecular weight of preferably 10,000-22,000. The optical disk base produced by using the molding material has extremely little generation of small white spots even after keeping under high-temperature and humidity condition over a long period and is useful as a base for DVD(digital versatile disk) such as CD-R, CD-RW and digital video disk. |
