| 摘要 |
PROBLEM TO BE SOLVED: To efficiently smoothen a surface body of an end face of a glass substrate or the like at low cost by grinding the inner peripheral end face and/or an outer peripheral end face of a disc body comprising a circular hole on a central part with the use of the grinding liquid including the free abrasive grain. SOLUTION: A grinding device comprises a glass substrate (MD substrate) for a magnetic disc to be ground, a substrate case for storing a number of MD substrates 1 in a state that they are dipped in the grinding liquid, a rotary holding table 3 for rotatably fixing and supporting the substrate case 2, a rotary brush 4 inserted into the inner peripheral hole parts of a number of stacked MD substrates 1, a grinding liquid storing part 5 for storing the grinding liquid including the free abrasive grain, or the like. The grinding is performed in a state that the rotary holding table 3 and the rotary brush 4 are rotated in the directions opposite to each other. On this occasion, the revolution speed of the rotary holding table 3 is about 60 rpm, that of the rotary brush 4 is about 4000 rpm, and the grinding time is about 10 minutes. As the result, the surface roughness of the inner peripheral end face of the glass substrate can be improved. |
