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:
Mar. 29, 1994
Filed:
Nov. 10, 1992
Applicant:
Inventors:
Peter R Ivett, Totton, GB;
Kenneth E Johnson, Rochester, MN (US);
Richard E Nelson, Rochester, MN (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
428336 ; 428611 ; 428667 ; 4286 / ; 428900 ; 428928 ;
Abstract
In a rigid magnetic recording disk, the magnetic properties, such as the coercivity, of a cobalt based, hard, magnetic alloy, such as a cobalt-platinum-chromium (CoPtCr) thin film magnetic recording layer, are controlled by providing a thin, sputtered, underlayer of a nonmagnetic, binary, chromium-tungsten (CrW) alloy whose major constituent is chromium, and preferably of a composition Cr.sub.88 W.sub.12 upon which the thin film magnetic recording layer is subsequently sputter deposited.