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. 20, 2026
Filed:
Aug. 07, 2024
Resonac Corporation, Tokyo, JP;
Yuki Sato, Chiba, JP;
Takayuki Fukushima, Chiba, JP;
Takeshi Sakamoto, Chiba, JP;
Hisato Shibata, Tokyo, JP;
Takehiro Yamaguchi, Chiba, JP;
Masaru Tajima, Chiba, JP;
Resonac Hard Disk Corporation, Chiba, JP;
Abstract
A magnetic recording medium includes a nonmagnetic substrate, an underlayer disposed above the nonmagnetic substrate, and a magnetic recording layer disposed above the underlayer. The magnetic recording layer includes a first magnetic layer disposed above the underlayer, and a second magnetic layer disposed above the first magnetic layer. Each of the first magnetic layer and the second magnetic layer has a granular structure including magnetic grains having a L1structure and a grain boundary portion. The grain boundary portion of the first magnetic layer includes aluminum nitride, and the grain boundary portion of the second magnetic layer includes hexagonal boron nitride. An aluminum nitride content in the first magnetic layer is in a range of 15 vol % to 35 vol %, and a peak in a B1spectrum of the grain boundary portion of the second magnetic layer observed using X-ray photoelectron spectroscopy is 191.6 eV or less.