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:
Feb. 27, 2007
Filed:
Jan. 17, 2003
Miyabi Nakamura, Ibaraki, JP;
Takahiro Shimizu, Nagano, JP;
Hiroyuki Uwazumi, Nagano, JP;
Naoki Takizawa, Nagano, JP;
Tadaaki Oikawa, Nagano, JP;
Miyabi Nakamura, Ibaraki, JP;
Takahiro Shimizu, Nagano, JP;
Hiroyuki Uwazumi, Nagano, JP;
Naoki Takizawa, Nagano, JP;
Tadaaki Oikawa, Nagano, JP;
Fuji Electric Co., Ltd., , JP;
Abstract
A magnetic recording medium for perpendicular magnetic recording system includes a nonmagnetic substrate and layers sequentially laminated on the substrate. The layers include a seed layer comprised of a metal or an alloy with a face centered cubic crystal structure, a nonmagnetic underlayer of a metal or an alloy with a hexagonal closest packed crystal structure, a magnetic layer having a granular structure including ferromagnetic crystalline grains with a hexagonal closest packed structure and nonmagnetic grain boundary region of mainly oxide surrounding the crystalline grains, a protective layer, and a liquid lubricant layer.