Magnetic recording medium
AssigneeHitachi, Ltd.
InventorsYoshihiro Shiroishi, Sadao Hishiyama, Hiroyuki Suzuki, Norikazu Tsumita, Tsuneo Suganuma, Yoshio Gobara, Masaaki Hayashi, Makoto Sano, Takaaki Shirakura
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Abstract
A magnetic recording medium comprises a non-magnetic substrate and a thin magnetic film, the thin magnetic film being composed mainly of Co, Ni and at least one of Zr and Hf, and a concentration of Zr, Hf or Zr and Hf as contained in the thin magnetic film being 0.1 to 30% by atom on the basis of the total of Co and Ni, and has a considerably higher corrosion resistance than that of the conventional magnetic recording medium having a thin Co-Ni magnetic film.
Claims26
A magnetic recording medium which comprises a non-magnetic substrate and a thin magnetic film formed thereon, the thin magnetic film consisting essentially of Co, Ni and Zr, and a concentration of Zr being 0.1 to 30% by atom on the total of Co and Ni wherein said Zr is concentrated predominantly near the surface of the thin magnetic film.
A magnetic recording medium, which comprises a non-magnetic substrate and a thin magnetic film formed thereon, the thin magnetic film consisting essentially of Co, Ni and Hf, and a concentration of Hf being 0.1 to 30% by atom on the basis of the total of Co and Ni wherein said Hf is concentrated predominantly near the surface of the thin magnetic film.
A magnetic recording medium, which comprises a non-magnetic substrate and a thin magnetic film formed thereon, the thin magnetic film being consisting essentially of Co, Ni, Hf and Zr, and a concentration of Hf and Zr being 0.1 to 30% by atom on the basis of the total of Co and Ni wherein said Zr and said Hf are concentrated predominantly near the surface of the tine magnatic film.
A magnetic recording medium which comprises a non-magnetic substrate and a thin magnetic film formed thereon, the thin magnetic film consisting essentially of Co, Ni and either Zr, Hf, or mixtures thereof, a concentration of Ni being 10 to 60% by atom on the basis of Co and a concentration of Zr, Hf, or mixtures thereof being 0.1 to 30% by atom on the total of Co and Ni;
- the Zr, Hf or mixtures thereof being concentrated predominantly near the surface of the thin magnetic film.
Dependencies are inferred from the claim text.