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:
Aug. 24, 2010
Filed:
Aug. 31, 2007
Shunji Takenoiri, Matsumoto, JP;
Yasushi Sakai, Matsumoto, JP;
Shunji Takenoiri, Matsumoto, JP;
Yasushi Sakai, Matsumoto, JP;
Fuji Electric Device Technology Co., Ltd., Tokyo, JP;
Abstract
A perpendicular magnetic recording medium composed of a nonmagnetic substrate having a surface onto which are provided a plurality of layers including, in the order recited, a soft underlayer; a nonmagnetic coupling layer; a hard magnetic pinning layer which is antiferromagnetically coupled to the soft underlayer at ambient temperature via the nonmagnetic coupling layer and which has an axis of easy magnetization which extends in a direction which is perpendicular to that of the surface of the nonmagnetic substrate; a nonmagnetic intermediate layer; and a magnetic recording layer. Such a perpendicular magnetic recording medium has an improved medium performance, with reduced noise originating from the presence of the soft underlayer, and no erasure of recorded magnetization when influenced by an external magnetic field.