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:
May. 17, 2016
Filed:
Feb. 28, 2014
Kabushiki Kaisha Toshiba, Minato-ku, JP;
Akira Watanabe, Kawasaki, JP;
Takeshi Iwasaki, Inagi, JP;
Kazutaka Takizawa, Kawasaki, JP;
Kaori Kimura, Yokohama, JP;
KABUSHIKI KAISHA TOSHIBA, Minato-ku, JP;
Abstract
According to one embodiment, a perpendicular magnetic recording medium is provided, which includes a non-magnetic granular underlayer formed on a substrate and containing metal grains of a first metal and a grain boundary layer surrounding the metal grains, each metal grain including a projection projecting from the boundary layer and a bottom portion embedded in the grain boundary layer, and a contact angle of the edge of the projection to the surface of the grain boundary layer being 45° to 85°, a non-magnetic intermediate layer formed on a surface of each projection and a magnetic recording layer having a projection pattern formed on the basis of a pattern of the projections in the non-magnetic intermediate layer via the non-magnetic intermediate layer.