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. 09, 1996
Filed:
Nov. 10, 1993
Applicant:
Inventors:
Ryuji Sugita, Hirakata, JP;
Kiyokazu Tohma, Hirakata, JP;
Tatsuaki Ishida, Sakai, JP;
Yasuaki Ban, Neyagawa, JP;
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka-Fu, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01F / ; G11B / ; G11B / ;
U.S. Cl.
CPC ...
4286 / ; 428611 ; 428678 ; 4286 / ; 4286 / ; 4286 / ; 4286 / ; 428900 ;
Abstract
A magnetic recording medium has a cobalt-based first magnetic layer and a cobalt-based second magnetic layer which are formed on a substrate of high polymer by vacuum evaporation. In order to have a high reproducing output and a high S/N ratio, the first magnetic layer has high oxygen density area which is arranged at a vicinity of the second magnetic layer, and the second magnetic layer has high oxygen density area which is arranged at a vicinity of the first magnetic layer.