| 摘要 |
PROBLEM TO BE SOLVED: To provide a polishing method capable of efficiently making the inner circumferential end face highly smooth at a low cost by supplying a polishing liquid containing free abrasive grains to the inner circumferential end face of each of disk-shaped glass substrates with a circular hole at the center followed by bringing a polishing brush into rotary contact with the end faces. SOLUTION: This polishing method comprises the following practice: a number of magnetic disk substrates (MD substrates) 1 each with a circular hole at the center are stacked vertically and held in a substrate case 2, and collars 21 disposed on the top and bottom thereof are clamped with a cover 22; the resulting substrate case 2 is set on a rotary holding table 3, a rotary brush 4 is then threaded onto the inner circumferential part of the circular hole of the MD substrates 1, and the bristles 43 of the brush 4 are situated over a span ranging from the lowermost part 1' to the uppermost part 1" of the MD substrates 1; subsequently, a polishing liquid 50 is fed at a flow of about 500-3,000 mL/min from a relevant feed section 5 toward the circumferential part of the MD substrates 1, the rotary holding table 3 and the rotary brush 4 are then rotated reversely to each other and the polishing liquid 50 is sucked downward by the aid of the rotation of the brush 4. |
