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:
Jun. 08, 2021
Filed:
Apr. 02, 2018
Applicant:
Hoya Corporation, Tokyo, JP;
Inventor:
Kinobu Osakabe, Tokorozawa, JP;
Assignee:
HOYA CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 5/73 (2006.01); G11B 5/82 (2006.01);
U.S. Cl.
CPC ...
G11B 5/73915 (2019.05); G11B 5/73919 (2019.05); G11B 5/73921 (2019.05); G11B 5/82 (2013.01);
Abstract
A non-magnetic substrate for a magnetic disk includes a substrate main body having two opposing main surfaces, and a metal film that is provided on the main surfaces and is made of a material having a loss factor of 0.01 or more. The non-magnetic substrate has a thickness (T+D) of 0.700 mm or less, the thickness (T+D) being the sum of a thickness T of the substrate main body and a thickness D of the metal film, and a ratio D/T of the thickness D of the metal film to the thickness T of the substrate main body is 0.025 or more.