The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 12, 2000
Filed:
Sep. 29, 1998
Kousaku Tamari, Hiroshima, JP;
Takanori Doi, Hatsukaichi, JP;
Yasuo Kakihara, Hiroshima, JP;
Kenichi Nakata, Otake, JP;
Toda Kogyo Corporation, Hiroshima-ken, JP;
Abstract
A magnetic recording medium of the present invention comprises: a substrate; a nickel oxide underlayer formed on said substrate; and a cobalt-containing maghemite thin film formed on said nickel oxide underlayer, having either a spacing of a (311) plane of not more than 2.510 .ANG., a spacing of a (222) plane of not more than 2.415 .ANG. or a spacing of a (220) plane of not more than 2.950 .ANG., and having the ratio of either of X-ray diffraction spectrum peak intensities of the (311), (222) or (220) planes of said cobalt-containing maghemite thin film to an X-ray diffraction spectrum peak intensity of the (400) plane of more than 0.5:1. Such a magnetic recording medium has a higher coercive force, a higher saturation magnetization, less amount of noise generated, a large output in a high recording frequency region and less distortion of a reproduced waveform, and is suitable for use in current magnetic recording systems in which a ring-type magnetic write head is used.