公开(公告)号：US11244700B2

公开(公告)日：2022-02-08

申请号：US16169065

申请日：2018-10-24

申请人： SHOWA DENKO K.K.

发明人： Katsumi Murofushi ,  Yoshitaka Ishibashi ,  Takayuki Fukushima ,  Kazuya Niwa ,  Lei Zhang ,  Yuji Murakami ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Chen Xu ,  Tetsuya Kanbe ,  Tomoo Shige

IPC分类号： G11B5/65 ,  G11B5/72 ,  G11B5/82 ,  G11B5/851 ,  C08L61/28

摘要： A magnetic recording medium includes a substrate, an underlayer provided on the substrate, and a magnetic layer provided on the underlayer and having a L10 structure and a (001) orientation. The magnetic layer has a granular structure in which an organic compound having a methylene skeleton or a methine skeleton is arranged at grain boundaries of magnetic grains.

公开(公告)号：US11676632B2

公开(公告)日：2023-06-13

申请号：US17104504

申请日：2020-11-25

申请人： SHOWA DENKO K.K.

发明人： Takayuki Fukushima ,  Lei Zhang ,  Chen Xu ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Hiroshi Koyanagi ,  Yuji Umemoto

IPC分类号： G11B5/73 ,  G11B5/851 ,  C23C14/08 ,  C23C14/34 ,  C23C14/00 ,  G11B5/716 ,  C23C14/35

CPC分类号： G11B5/736 ,  C23C14/0057 ,  C23C14/081 ,  C23C14/34 ,  C23C14/35 ,  G11B5/716 ,  G11B5/7369 ,  G11B5/851 ,  Y10T428/115

摘要： The present invention relates to a magnetic recording medium including a substrate; an underlayer laminated upon the substrate; and a magnetic layer laminated upon the underlayer, wherein the underlayer includes a first underlayer containing a compound represented by a following general formula: MgO(1-X), where X is within a range of 0.07 to 0.25, the magnetic layer includes a first magnetic layer containing an alloy having a L10 structure, and the alloy having the L10 structure includes B, and the first underlayer is in contact with the first magnetic layer.

公开(公告)号：US11189313B2

公开(公告)日：2021-11-30

申请号：US17141367

申请日：2021-01-05

申请人： SHOWA DENKO K.K.

发明人： Koichi Nagasaka ,  Takayuki Fukushima ,  Lei Zhang ,  Chen Xu ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Hiroshi Koyanagi ,  Yuji Umemoto

IPC分类号： G11B5/70 ,  G11B5/706 ,  G11B5/73 ,  G11B5/33 ,  G11B5/851 ,  G11B5/716 ,  G11B5/66

摘要： A magnetic recording medium includes a substrate, an underlayer provided above the substrate, and a magnetic layer provided on and in contact with the underlayer. The underlayer includes a compound represented by a general formula MgO(1-x), where x falls within a range of 0.07 to 0.25. The magnetic layer includes an alloy having a L10 structure, and the alloy having the L10 structure includes one or more elements selected from a group consisting of Al, Si, Ga, and Ge.

公开(公告)号：US11037591B2

公开(公告)日：2021-06-15

申请号：US16433377

申请日：2019-06-06

申请人： SHOWA DENKO K.K.

发明人： Lei Zhang ,  Chen Xu ,  Takayuki Fukushima ,  Kazuya Niwa ,  Tetsuya Kanbe ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Tomoo Shige

IPC分类号： G11B5/73 ,  G11B5/65 ,  G11B5/00

摘要： A heat-assisted magnetic recording medium includes: a substrate; an underlayer; and a magnetic layer including an alloy having an L10 structure, wherein the underlayer includes, from the substrate side, a bcc underlayer including a substance having a bcc structure, a first oxide layer that is in contact with the bcc underlayer, and a second oxide layer that is in contact with the magnetic layer. The bcc underlayer, the first oxide layer, and the second oxide layer are stacked in the recited order. The first oxide layer and the second oxide layer include magnesium oxide, and the second oxide layer further includes one or more compounds selected from the group consisting of vanadium oxide, vanadium nitride, and vanadium carbide.

公开(公告)号：US10008220B2

公开(公告)日：2018-06-26

申请号：US15596109

申请日：2017-05-16

申请人： SHOWA DENKO K.K.

发明人： Takayuki Fukushima ,  Yuji Murakami ,  Tetsuya Kanbe ,  Lei Zhang ,  Kazuya Niwa ,  Hisato Shibata

IPC分类号： G11B5/82 ,  G11B5/187 ,  G11B5/706 ,  G11B5/74 ,  G11B5/716 ,  G11B5/855 ,  G11B5/39 ,  G11B5/66 ,  G11B5/73 ,  G11B5/84 ,  G11B5/65

CPC分类号： G11B5/1875 ,  G11B5/398 ,  G11B5/65 ,  G11B5/66 ,  G11B5/706 ,  G11B5/70615 ,  G11B5/716 ,  G11B5/73 ,  G11B5/743 ,  G11B5/82 ,  G11B5/8404 ,  G11B5/855

摘要： A magnetic recording medium includes a substrate; a lower base layer formed on the substrate; and a (001) oriented L10 magnetic layer formed on the lower base layer and including a first magnetic layer formed on the lower base layer and having a granular structure of magnetic grains and a grain boundary portion, the grain boundary portion containing C, and a second magnetic layer formed on the first magnetic layer and having a granular structure of magnetic grains and a grain boundary portion, the grain boundary portion containing oxide or nitride, the second magnetic layer further containing one or more elements selected from a group consisting of Mg, Ni, Zn, Ge, Pd, Sn, Ag, Re, Au and Pb as an additive.

公开(公告)号：US11024334B2

公开(公告)日：2021-06-01

申请号：US16835770

申请日：2020-03-31

申请人： SHOWA DENKO K.K.

发明人： Takayuki Fukushima ,  Chen Xu ,  Lei Zhang ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Kazuya Niwa ,  Tomoo Shige ,  Hiroaki Nemoto ,  Yuji Umemoto ,  Hiroshi Koyanagi

IPC分类号： G11B11/105 ,  G11B5/65 ,  G11B5/66 ,  G11B5/60 ,  G11B5/00

摘要： A magnetic recording medium includes a substrate, an underlayer, and a magnetic layer that are arranged in this order. The magnetic layer has a granular structure including magnetic grains having a L10 crystal structure, and grain boundary parts having a volume fraction in a range of 25 volume % to 50 volume %. The magnetic grains have a c-axis orientation with respect to the substrate. The grain boundary parts include a material having a lattice constant in a range of 0.30 nm to 0.36 nm, or in a range of 0.60 nm to 0.72 nm.

公开(公告)号：US10803895B2

公开(公告)日：2020-10-13

申请号：US15859973

申请日：2018-01-02

申请人： SHOWA DENKO K.K.

发明人： Takayuki Fukushima ,  Haruhisa Ohashi ,  Lei Zhang ,  Yuji Murakami ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Tetsuya Kanbe

IPC分类号： G11B5/65 ,  G11B5/73 ,  G11B5/00

摘要： A magnetic recording medium includes: a substrate; a first underlayer; a second underlayer; and a magnetic layer including an alloy having a L10 type crystal structure with a (001) orientation. The substrate, the first underlayer, the second underlayer, and the magnetic layer are stacked in this order. The first underlayer is a crystalline layer that includes Mo as a main component. The second underlayer is a crystalline layer that includes a material containing Mo as a main component and that includes an oxide. The content of the oxide in the second underlayer is in a range of from 2 mol % to 30 mol %. The oxide is an oxide of one or more kinds of elements selected from a group consisting of Cr, Mo, Nb, Ta, V, and W.

公开(公告)号：US10283154B2

公开(公告)日：2019-05-07

申请号：US15979965

申请日：2018-05-15

申请人： SHOWA DENKO K.K. ,  TOHOKU UNIVERSITY

发明人： Shintaro Hinata ,  Shin Saito ,  Takayuki Fukushima ,  Haruhisa Ohashi ,  Kazuya Niwa ,  Lei Zhang ,  Yuji Murakami ,  Hisato Shibata ,  Takehiro Yamaguchi ,  Tetsuya Kanbe ,  Tomoo Shige

IPC分类号： G11B5/65 ,  G11B5/66 ,  G11B5/48 ,  G11B5/73 ,  G11B5/00 ,  G11B5/60

摘要： A magnetic recording medium includes a substrate, a barrier layer, a crystal grain size control layer, and a magnetic layer that are arranged in this order. The barrier layer includes at least one of oxides, nitrides, and carbides, and the crystal grain size control layer is a crystalline layer including Ag and having an average thickness in a range of 0.1 nm to 1 nm. The barrier layer makes contact with the crystal grain size control layer, and the magnetic layer includes an alloy having a L10 crystal structure and a (001) face orientation.

公开(公告)号：US11545176B2

公开(公告)日：2023-01-03

申请号：US17658003

申请日：2022-04-05

申请人： SHOWA DENKO K.K.

发明人： Takayuki Fukushima ,  Tomoo Shige ,  Yuji Umemoto ,  Kazuya Niwa

IPC分类号： G11B5/00 ,  G11B11/105 ,  G11B5/65 ,  G11B5/012 ,  G11B5/127

摘要： A magnetic recording medium includes a substrate, and a magnetic recording layer including magnetic grains having an L10 structure. The magnetic recording layer is (001) oriented, and a surface of growth of the magnetic recording layer includes a (001) plane, a (111) plane, and planes equivalent to the (111) plane. An area ratio of the (111) plane and the planes equivalent to the (111) plane, represented by (A111+A111e)/(A001+A111+A111e), is in a range of 0.2 to 0.7, where A111 denotes an area of the (111) plane, A111e denotes an area of the planes equivalent to the (111) plane, and A001 denotes an area of the (001) plane.

公开(公告)号：US11043238B1

公开(公告)日：2021-06-22

申请号：US17116223

申请日：2020-12-09

申请人： SHOWA DENKO K.K.

发明人： Takehiro Yamaguchi ,  Takayuki Fukushima ,  Lei Zhang ,  Hisato Shibata ,  Chen Xu ,  Hiroshi Koyanagi ,  Yuji Umemoto

IPC分类号： G11B5/73 ,  G11B5/706

摘要： A magnetic recording medium includes a substrate; a soft magnetic underlayer laminated on the substrate; an amorphous barrier layer laminated on the soft magnetic underlayer; and a magnetic recording layer laminated on the amorphous barrier layer, wherein the soft magnetic underlayer includes Fe, B, Si, and one or more elements selected from the group consisting of Nb, Zr, Mo, and Ta, wherein the amorphous barrier layer includes Si, W, and one or more elements selected from the group consisting of Nb, Zr, Mo, and Ta, and wherein the magnetic recording layer includes an alloy having an L10 structure.