公开(公告)号：US20220246176A1

公开(公告)日：2022-08-04

申请号：US17649588

申请日：2022-02-01

Applicant: SHOWA DENKO K.K.

Inventor： Yoshitaka AONO ,  Takahiro UKAI ,  Takanao EBISAWA ,  Kazuya NIWA ,  Takayuki KONNO

IPC: G11B5/667 ,  G11B5/851

Abstract: A magnetic recording medium including: a non-magnetic substrate; an underlayer; a perpendicular magnetic layer; a diffusion preventing layer; and a protective layer, wherein the underlayer, the perpendicular magnetic layer, the diffusion preventing layer, and the protective layer are layered on the non-magnetic substrate in this order, the perpendicular magnetic layer has a multi-layer structure, the perpendicular magnetic layer includes an uppermost layer and at least one layer other than the uppermost layer, the uppermost layer including Co or Fe in magnetic particles, and the at least one layer other than the uppermost layer including an oxide, the diffusion preventing layer is provided between the perpendicular magnetic layer and the protective layer, and the diffusion preventing layer includes at least one component selected from a group consisting of Si, Ti, Cr, B, and Ru, or either a carbide, an oxide, or both, of the at least one component.

公开(公告)号：US20230131031A1

公开(公告)日：2023-04-27

申请号：US18146647

申请日：2022-12-27

Applicant: SHOWA DENKO K.K.

Inventor： Yoshitaka AONO ,  Takahiro UKAI ,  Takanao EBISAWA ,  Kazuya NIWA ,  Takayuki KONNO

IPC: G11B5/667 ,  G11B5/851

Abstract: A method of manufacturing a magnetic recording medium including: forming a diffusion preventing layer, wherein the magnetic recording medium includes a non-magnetic substrate; an underlayer; a perpendicular magnetic layer; the diffusion preventing layer; and a protective layer, wherein the perpendicular magnetic layer has a multi-layer structure, the perpendicular magnetic layer includes an uppermost layer and at least one layer other than the uppermost layer, the uppermost layer including Co or Fe in magnetic particles, and the at least one layer other than the uppermost layer including an oxide, the diffusion preventing layer is provided between the perpendicular magnetic layer and the protective layer, and the diffusion preventing layer includes at least one component selected from a group consisting of Si, Ti, Cr, B, and Ru, or either a carbide, an oxide, or both, of the at least one component.