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. 15, 2013
Filed:
Aug. 02, 2011
Sadayuki Watanabe, Matsumoto, JP;
Sadayuki Watanabe, Matsumoto, JP;
Fuji Electric Co., Ltd., , JP;
Abstract
A perpendicular magnetic recording medium is disclosed that enables a high track density while maintaining good OW characteristics, SNR, and thermal stability. The medium includes a magnetic recording layer on a non-magnetic base, wherein the magnetic recording layer includes a first magnetic layer, a first exchange coupling control layer, a second magnetic layer, a third magnetic layer, and a fourth magnetic layer, in that order. It is preferable that when the perpendicular magnetic anisotropy constants of the first magnetic layer, second magnetic layer, third magnetic layer, and fourth magnetic layer are Ku, Ku, Ku, and Kurespectively, relationships of Ku>Ku>Kuand Ku>Ku>Kuare satisfied.