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:
Nov. 28, 2006
Filed:
Mar. 17, 2004
Takeshi Iwasaki, Funabashi, JP;
Takashi Hikosaka, Tokyo, JP;
Soichi Oikawa, Chiba, JP;
Futoshi Nakamura, Ichikawa, JP;
Tomoyuki Maeda, Funabashi, JP;
Hiroshi Sakai, Ichihara, JP;
Kenji Shimizu, Ichihara, JP;
Akira Sakawaki, Ichihara, JP;
Takeshi Iwasaki, Funabashi, JP;
Takashi Hikosaka, Tokyo, JP;
Soichi Oikawa, Chiba, JP;
Futoshi Nakamura, Ichikawa, JP;
Tomoyuki Maeda, Funabashi, JP;
Hiroshi Sakai, Ichihara, JP;
Kenji Shimizu, Ichihara, JP;
Akira Sakawaki, Ichihara, JP;
Kabushiki Kaisha Toshiba, Tokyo, JP;
Showa Denko K. K., Tokyo, JP;
Abstract
Disclosed is a perpendicular magnetic recording medium in which an undercoating layer having crystal grains and a grain boundary material containing a carbide or boride is formed below a perpendicular magnetic recording layer, and another undercoating layer containing one of elements forming the crystal grains is formed below the aforementioned undercoating layer, and which can perform high□density recording by further decreasing the grain size of the perpendicular magnetic recording layer.