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:
Nov. 17, 2020
Filed:
Oct. 31, 2018
Applicant:
Sony Corporation, Tokyo, JP;
Inventors:
Eiji Nakashio, Miyagi, JP;
Minoru Yamaga, Miyagi, JP;
Masaru Terakawa, Miyagi, JP;
Yoichi Kanemaki, Miyagi, JP;
Katsunori Maeshima, Miyagi, JP;
Jun Hashimoto, Miyagi, JP;
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 5/706 (2006.01); G11B 5/714 (2006.01); G11B 5/70 (2006.01); G11B 5/78 (2006.01);
U.S. Cl.
CPC ...
G11B 5/70642 (2013.01); G11B 5/70 (2013.01); G11B 5/70621 (2013.01); G11B 5/70678 (2013.01); G11B 5/714 (2013.01); G11B 5/78 (2013.01);
Abstract
The magnetic recording medium includes a support and a magnetic layer containing a magnetic powder. The magnetic powder includes at least either of a magnetic particle containing a cubic ferrite and a magnetic particle containing an ε-phase iron oxide. The magnetic powder has a mean particle size of 10 nm or more and 14 nm or less, the magnetic powder has a mean aspect ratio of 0.75 or more and 1.25 or less, and the magnetic layer has a ten-point mean roughness Rz of 35 nm or less.