Ag Technology Co., Ltd.

Kyoko Hyomi

Yuzo Murayama

Naohiko Ishimaru

Akihiko Tashiro

Haruhiko Otsuka

A magnetic disc having one or multiple undercoat layers, a continuous thin film magnetic layer or continuous thin film multiple magnetic layers, a protective layer and a lubricant layer sequentially laminated on a non-magnetic disc substrate, which has surface roughness on the surface of the magnetic disc, said surface roughness being such that when the surface roughness is measured by an atomic force microscope or a scanning tunnel microscope, the maximum peak height is from 150 .ANG. to 800 .ANG. based on the height giving the highest frequency in the height distribution of the surface roughness, and the depth (D.sub.0.5) at a bearing ratio of 0.5% from the highest point is from 80 .ANG. to 450 .ANG..

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Yokohama, Japan

Kyoko Hyomi