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. 23, 2011
Filed:
Mar. 20, 2006
Yoshiaki Sonobe, Shinjuku-ku, JP;
Teiichiro Umezawa, Shinjuku-ku, JP;
Kong Kim, Shinjuku-ku, JP;
Masaki Uemura, Shinjuku-ku, JP;
Yoshiaki Sonobe, Shinjuku-ku, JP;
Teiichiro Umezawa, Shinjuku-ku, JP;
Kong Kim, Shinjuku-ku, JP;
Masaki Uemura, Shinjuku-ku, JP;
WD Media, Inc., San Jose, CA (US);
Abstract
A magnetic diskfor use in perpendicular magnetic recording, which includes an underlayer, a size-reduction promoting layer(nonmagnetic granular layer) of a granular structure, and a magnetic recording layerhaving a ferromagnetic layerof a granular structure. The size-reduction promoting layerhas an inorganic oxide matrix and nonmagnetic metal crystal grains and is disposed between the underlayerand the ferromagnetic layer, thereby reducing the size of magnetic crystal grains in the ferromagnetic layer