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. 21, 2002
Filed:
Sep. 13, 2000
Kazutoshi Katayama, Odawara, JP;
Kazuyuki Usuki, Odawara, JP;
Fuji Photo Film Co., Ltd., Kanagawa, JP;
Abstract
A magnetic recording medium, comprising a magnetic layer containing a ferromagnetic metal thin film having micro-size projections on surface thereof and formed by vacuum film forming method and provided at least on one side of a nonmagnetic substrate, a carbon protective layer and a lubricant provided on said magnetic layer, a central axis of a diamond indenter of trilateral pyramid having a tip sharp angle of 90° and a radius of curvature at tip of 35-50 nm being directed perpendicularly to the surface of the nonmagnetic substrate, pressure is applied on the carbon protective layer, and a load obtained when indentation depth of the indenter is 10-25 nm is divided by projection area of indenter contactor, and the quotient, i.e. micro-hardness, is within the range of 10-30 GPa.