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:
Jan. 02, 2007
Filed:
Apr. 14, 2004
Naoto Yajima, Tokyo, JP;
Takayoshi Kuwajima, Tokyo, JP;
Akihiko Seki, Tokyo, JP;
Hiroyuki Yamada, Tokyo, JP;
Kenichi Kitamura, Tokyo, JP;
Naoto Yajima, Tokyo, JP;
Takayoshi Kuwajima, Tokyo, JP;
Akihiko Seki, Tokyo, JP;
Hiroyuki Yamada, Tokyo, JP;
Kenichi Kitamura, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
The present invention provides a magnetic recording medium comprising a magnetic layer with excellent surface smoothness, which comprises a thin film magnetic layer of thickness in a range from 0.03 to 0.30 μm that is ideal for short wavelength recording, and displays superior electromagnetic conversion characteristics. The magnetic recording medium comprises a magnetic layer containing at least a ferromagnetic powder and a binder resin on one surface of a non-magnetic support, wherein the thickness of the magnetic layer is within a range from 0.03 to 0.30 μm, and the number of concavities with a depth of 30 nm or greater in the surface of the magnetic layer is 5 per 1 cmof surface area or less. Preferably, the value of the average depth Rv6 of the surface of the magnetic layer, as measured by a contact type surface roughness meter, is 12 nm or less.