| 摘要 |
PROBLEM TO BE SOLVED: To make it possible to precisely mold the grooves of a disk substrate and to increase the density in the track width direction in a transverse direction by molding the disk substrate exactly meeting its design. SOLUTION: This stamper has flat front surface parts 13, plural projecting parts 11 for forming the grooves 3 having a air of rising flanks 14 disposed on both sides of these front surface parts 13 and plural recessed parts 12 which are disposed continuously with the rising flanks 14 of the respective projecting parts 11 and have flat base parts 15. The base parts 15 of the recessed parts 12 are provided with projecting parts 5 for accumulating gases at the time of molding the magnetic recording medium substrate in an inward direction. |
