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. 23, 1990
Filed:
Dec. 15, 1987
Applicant:
Inventors:
Tadao Tokushima, Hamamatsu, JP;
Makoto Shiraki, Hamamatsu, JP;
Yoshifumi Suzuki, Hamamatsu, JP;
Yukio Wakui, Hamamatsu, JP;
Assignee:
Yamaha Corporation, , JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
428336 ; 427130 ; 427131 ; 427132 ; 428433 ; 428469 ; 428694 ; 428900 ;
Abstract
In construction of a magnetic recording material having overlaid anodic oxide layers and well suited for perpendicular magnetic recording, a substrate is made of a hard material and Al predominant layers of 0.1 to 2 .mu.m thickness and formed on the substrate as a base for the overlaid anodic oxide layers for improvement in mechanical properties with acceptable magnetic recording characteristics.