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. 20, 1994
Filed:
Mar. 24, 1993
Motoharu Sato, Kobe, JP;
Yoshihiko Onishi, Kobe, JP;
Kabushiki Kaisha Kobe Seiko Sho, Kobe, JP;
Abstract
An object of the present invention is to obtain a magnetic disk which has a high coercive force. It has a constitution in which, at first, a Cr under layer, a magnetic layer of a Co alloy, and a protective layer, a Zr layer for example, are formed in order on a substrate, and it is heat-processed at a temperature of higher than 250.degree. C. The Zr layer is changed to an oxide layer, etc. by the heating process and becomes a layer which functions as a protective layer, and on the other hand, a chemical compound of Zr and a non-magnetic element in the magnetic layer of a Co alloy, Cr for example, is not generated, so that the segregation of Cr into the crystalline grain boundaries of the magnetic layer of a Co alloy is more effectively expedited. Because of this, since magnetic interactions between the crystalline grains in the magnetic layer of a Co alloy are weakened, the disks having high coercive force can be obtained.