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:
Oct. 24, 1989
Filed:
Jun. 29, 1988
Applicant:
Inventors:
Assignee:
Sumitomo Special Metals, Co., Ltd., Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ; C23C / ;
U.S. Cl.
CPC ...
20419215 ; 29603 ; 20419222 ; 360110 ; 360122 ; 427129 ; 428472 ; 4284722 ; 428694 ; 428900 ;
Abstract
A grooved magnetic substrate including an alumina film layer having a Knopp hardness of 600 kg/mm.sup.2 to 1200 kg/mm.sup.2 charged in at least one groove formed in a surface of a magnetic substrate. The magnetic substrate may be Mn-Zn or Ni--Zn base ferrite. The alumina film layer is formed by sputtering.
Wada, Toshiaki. (1989). Grooved magnetic substrates and method for producing the same (U.S. Patent No. 4875987). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/4875987
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile