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. 25, 2006
Filed:
Jun. 02, 2004
Hisao Kawai, Singapore, SG;
Teiichiro Umezawa, Tokyo, JP;
Hirotaka Tanaka, Tokyo, JP;
Masaki Uemura, Tokyo, JP;
Hisao Kawai, Singapore, SG;
Teiichiro Umezawa, Tokyo, JP;
Hirotaka Tanaka, Tokyo, JP;
Masaki Uemura, Tokyo, JP;
Hoya Corporation, Tokyo, JP;
Hoya Magnetics Singapore Pte. Ltd., Tuas Link 2, SG;
Abstract
In a magnetic recording medium including a substrate () having a principal surface on which first and second magnetic layers (and) and a spacer layer () are at least formed, each of the first and the second magnetic layers being of a ferromagnetic material, the spacer layer being formed between the first and the second magnetic layers for inducing antiferromagnetic exchange interaction between the first and the second magnetic layers, the principal surface of the substrate is provided with concentric textures to have a predetermined surface roughness so that the spacer layer has a uniform thickness. The first magnetic layer is for controlling the antiferromagnetic exchange interaction.