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:
Dec. 13, 2011
Filed:
Feb. 13, 2008
Yoshiaki Sonobe, Singapore, SG;
Takahiro Onoue, Singapore, SG;
Koichi Wago, San Jose, CA (US);
WD Media (Singapore) Pte. Ltd., Singapore, SG;
Abstract
A magnetic recording medium () has a substrate () and a perpendicular magnetic recording layer () formed over the substrate (). The perpendicular magnetic recording layer () has a granular layer () in which a magnetic signal is recorded and a continuous film layer () magnetically coupled to the granular layer (). The continuous film layer () has hard magnetic portions () formed in positions corresponding to the recording regions where magnetic signals are recorded in the granular layer () and magnetic shield portions () formed between the hard magnetic portions (), each having a magnetization curve whose slope is larger than those of the hard magnetic portions in the region where the applied magnetic filed is zero when the magnetization curve is measured, and each having a residual magnetic polarization smaller than those in the hard magnetic portions.