Magnetic recording medium and manufacturing method therefor
AssigneeHoya Corporation
InventorsHiroshi Tomiyasu, Junichi Horikawa, Teiichiro Umezawa, Kenji Ayama, Tomotaka Yokoyama
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Abstract
A magnetic recording medium that is high coersive force, hard to receive influence of thermal fluctuation, and brings about a considerable improvement of S/N ratio, and in which at least an underlayer and a magnetic layer are sequentially laminated on a substrate, wherein a pre-coat layer is interposed between said underlayer and said substrate and said pre-coat layer is constructed by sequentially laminating a lower layer containing Ni and P and an upper layer made of a Cr alloy.
Claims9
A magnetic recording medium in which at least an underlayer and a magnetic layer are sequentially formed on a glass substrate, wherein
- a pre-coat layer for decrease in size of crystal grains of the underlayer and the magnetic layer and for suppressing dispersion of grain size of the underlayer and the magnetic layer contains nitrogen and is formed by sputtering between said glass substrate and the underlayer, and
- in said pre-coat layer, a lower layer containing Ni and P and an upper layer made of a Cr alloy are sequentially laminated from said glass substrate side.
Dependencies are inferred from the claim text.