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:
Feb. 04, 2020
Filed:
Jun. 19, 2019
Showa Denko K.k., Tokyo, JP;
Lei Zhang, Chiba, JP;
Takayuki Fukushima, Chiba, JP;
Chen Xu, Chiba, JP;
Kazuya Niwa, Chiba, JP;
Hisato Shibata, Chiba, JP;
Takehiro Yamaguchi, Chiba, JP;
Tetsuya Kanbe, Chiba, JP;
Tomoo Shige, Chiba, JP;
SHOWA DENKO K.K., Tokyo, JP;
Abstract
A heat-assisted magnetic recording medium includes: a substrate; an underlayer; and a magnetic layer that is (001)-oriented. In the magnetic layer, a first magnetic layer and a second magnetic layer are stacked in this order from the underlayer side. The first magnetic layer and the second magnetic layer include an alloy having an L1structure. The second magnetic layer includes a ferrite at grain boundaries of magnetic grains. The ferrite is one or more kinds selected from the group consisting of NiFeO, MgFeO, MnFeO, CuFeO, ZnFeO, CoFeO, BaFeO, SrFeO, and FeO. A Curie temperature of the magnetic grains is lower than a Curie temperature of the ferrite.