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:
Jul. 11, 2000
Filed:
Nov. 10, 1998
Kazuhiko Nakayama, Tochigi-ken, JP;
Katsumi Endoh, Tochigi-ken, JP;
Takashi Ishii, Tochigi-ken, JP;
Takeshi Miyamura, Tochigi-ken, JP;
Osamu Yoshida, Tochigi-ken, JP;
Kao Corporation, Tokyo, JP;
Abstract
A magnetic recording medium comprising a substrate having an uppermost magnetic layer containing ferromagnetic metal powder and a lower magnetic layer which is adjacent to the uppermost magnetic layer, wherein the uppermost magnetic layer has an average dry thickness of 0.03 to 0.5 .mu.m, the ferromagnetic metal powder in the uppermost magnetic layer is orientated in the horizontal direction of the magnetic recording medium, the magnetic recording medium has a coercive force of 120 kA/m or higher in the horizontal direction thereof, and a ratio of a maximum magnetic susceptibility .chi..sub.max with an external magnetic field applied in the direction perpendicular to the magnetic recording medium to a magnetic susceptibility .chi..sub.8 with an external magnetic field of 8 kA/m applied in the same direction, .chi..sub.max /.chi..sub.8, is 1.3 or higher.