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. 13, 2015
Filed:
Oct. 14, 2008
Kazuaki Sakamoto, Tokyo, JP;
Kong Kim, Tokyo, JP;
Takahiro Onoue, Singapore, SG;
Masafumi Ishiyama, Singapore, SG;
Teiichiro Umezawa, Singapore, SG;
Kenji Ayama, Singapore, SG;
Kazuaki Sakamoto, Tokyo, JP;
Kong Kim, Tokyo, JP;
Takahiro Onoue, Singapore, SG;
Masafumi Ishiyama, Singapore, SG;
Teiichiro Umezawa, Singapore, SG;
Kenji Ayama, Singapore, SG;
WD Media (Singapore) PTE. LTD, Singapore, SG;
Abstract
A perpendicular magnetic recording medium includes a substrate, a soft magnetic layer, a pre-underlayer, an underlayer, and a main recording layer serving as a magnetic recording layer. The pre-underlayer contains seed crystal grains that serve as a base for crystal grains of the underlayer, and an addition substance that is added between the seed crystal grains and composed of an element having an atomic radius smaller than that of an element forming the seed crystal grains.