| 摘要 |
PURPOSE:To increase the read margin of data on an inner circumferential side and to improve reliability, and to facilitate manufacture, by setting the surface roughness of a magnetic recording medium less only on the inner circumference side without varying it on the outer circumferential side. CONSTITUTION:While the magnetic disk 3 is put a little bit closer to an upper and a lower press-contacting roll 23 at the inner circumference side 26 than at the outer circumference side 27, abrasive tapes 22 are rubbed against surfaces of the magnetic disk 3 to set the rubbing force of the abrasive tapes 22 to the surfaces of the magnetic layers 4 greater in a polishing treatment at the inner circumference side than at the outer circumference side, decreasing the surface roughness of the magnetic disk 3 gradually from the innermost circumference position to the outermost circumference position in the single polishing treatment. Consequently, the generation of a shoulder noise at the outer circumference side is eliminated and the read margin at the inner circumference side is increased to reduce read errors on inner circumferential tracks due to a peak shift. |
