| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a glass substrate for a magnetic recording medium, by which a glass substrate for a magnetic recording medium having high smoothness and little waviness on the surface thereof can be manufactured with high productivity. <P>SOLUTION: Diamond pads 20A, 20B, 20C are used in primary, secondary, and tertiary lapping processes, respectively. In the diamond pad 20A, the average grain diameter of diamond abrasive grains is 4 μm to 12 μm, and the content of the diamond abrasive grains is 5 to 70 vol.%. In the diamond pad 20B, the average grain diameter of diamond abrasive grains is 1 μm to 5 μm, and the content of the diamond abrasive grains is 5 to 80 vol.%. In the diamond pad 20C, the average grain diameter of diamond abrasive grains is from 0.2 μm to less than 2 μm, and the content of the diamond abrasive grains is 5 to 80 vol.%. A silicon oxide is used as an abrasive in a first polishing process without using a cerium oxide. <P>COPYRIGHT: (C)2012,JPO&INPIT |
