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:
Oct. 28, 2014
Filed:
Mar. 10, 2011
Applicant:
Hisato Kato, Hachioji, JP;
Inventor:
Hisato Kato, Hachioji, JP;
Assignee:
Fuji Electric Co., Ltd., Kawasaki-Shi, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 5/66 (2006.01); G11B 5/73 (2006.01); G11B 5/738 (2006.01);
U.S. Cl.
CPC ...
G11B 5/7325 (2013.01); G11B 5/738 (2013.01); G11B 5/66 (2013.01);
Abstract
A perpendicular magnetic recording medium includes at least a soft-magnetic underlayer, a non-magnetic underlayer, a ferromagnetic intermediate layer, a non-magnetic intermediate layer, and a perpendicular magnetic recording layer sequentially stacked on a non-magnetic substrate. In an embodiment, the ferromagnetic intermediate layer is formed of a CoCr based alloy, a product Bs·t of a saturation magnetic flux density and film thickness of the ferromagnetic intermediate layer is within a range of 0.15 to 3.6 T·nm, and the non-magnetic intermediate layer has a film thickness of 3 nm or more.