| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for an optical disk substrate which can be obtained at a high yield and is high in reliability. <P>SOLUTION: In the method for the optical disk substrate, the optical disk substrate is manufactured by molding polycarbonate resin, and the polycarbonate resin contains the total number of a foreign substances of one or more pieces/40 g and 36 or less pieces/40 g in terms of particle diameter of 15 μm or more out of which iron or an iron-contained foreign substance is 22 or less pieces/40 g. <P>COPYRIGHT: (C)2007,JPO&INPIT |
