公开(公告)号：US20180114541A1

公开(公告)日：2018-04-26

申请号：US15565050

申请日：2016-03-08

申请人： Sony Corporation

发明人： Eiji NAKASHIO ,  Futoshi SASAKI ,  Yuuichi MASUZAWA ,  Masaru TERAKAWA ,  Minoru YAMAGA ,  Yoichi KANEMAKI ,  Kazuya HASHIMOTO ,  Tomoe SATO ,  Nobuyuki SASAKI

IPC分类号： G11B5/733 ,  G11B5/73

CPC分类号： G11B5/733 ,  G11B5/70 ,  G11B5/731

摘要： Provided is a magnetic recording medium including: a support body; a base layer containing carbon particle powder and metal-containing particle powder; and a recording layer. In a recording surface, a maximum indentation depth h is 85≤h≤140, and a ratio d of a permanent strain to an elastic recovery (permanent strain/elastic recovery) is 0.95≤d≤1.25.

公开(公告)号：US20190013043A1

公开(公告)日：2019-01-10

申请号：US16070140

申请日：2016-12-14

申请人： Sony Corporation

发明人： Eiji NAKASHIO ,  Masaru TERAKAWA ,  Yoichi KANEMAKI ,  Tomoe SATO ,  Katsunori MAESHIMA ,  Nobuyuki SASAKI

IPC分类号： G11B5/65

摘要： The magnetic recording medium includes a long substrate body, and a magnetic layer including a powder of cubic crystal ferrite magnetic particles. The sum of a squareness ratio in the longitudinal direction and a squareness ratio in the vertical direction is 1.2 or more, and the difference of the squareness ratio in the longitudinal direction and the squareness ratio in the vertical direction is 0.15 or more.

公开(公告)号：US20220108723A1

公开(公告)日：2022-04-07

申请号：US17275578

申请日：2019-08-29

申请人： Sony Corporation

发明人： Hiroto ATAGI ,  Noboru SEKIGUCHI ,  Takashi AIZAWA ,  Tomoe OZAKI ,  Koji SUZUKI ,  Yoichi KANEMAKI ,  Teruo SAI ,  Ryoichi HIRATSUKA ,  Kazuya HASHIMOTO

IPC分类号： G11B5/66 ,  G11B5/706 ,  G11B5/714

摘要： A tape-like magnetic recording medium includes a reinforced substrate, and a recording layer arranged on the reinforced substrate, and the reinforced substrate includes a substrate that has a first face and a second face opposed to each other, and has an average thickness of 4 μm or smaller, and a metal layer that contains cobalt, arranged on the first face, the reinforced substrate by itself causing thereon a depth of indentation of 0.25 μm or shallower, when a 0.7-mm-diameter hard sphere is impressed against the second face under 5.0 gf load for 10 seconds.

公开(公告)号：US20190143637A1

公开(公告)日：2019-05-16

申请号：US16099625

申请日：2017-05-11

申请人： Sony Corporation

发明人： Eiji NAKASHIO ,  Yuta AKIMOTO ,  Tomoe SATO ,  Yoichi KANEMAKI ,  Nobuyuki SASAKI ,  Masaru TERAKAWA ,  Kazuya HASHIMOTO ,  Katsunori MAESHIMA ,  Minoru YAMAGA ,  Hikaru TERUI ,  Hiroyuki KOBAYASHI

IPC分类号： B32B7/02 ,  G11B5/735 ,  G11B5/738 ,  G11B5/78

摘要： A magnetic recording medium according to a first technique includes an elongated substrate having a first surface and a second surface, a first reinforcing layer disposed on the first surface, a second reinforcing layer disposed on the second surface, an adhesion suppressing layer disposed on the second reinforcing layer, and a recording layer disposed on the first reinforcing layer or the adhesion suppressing layer.

公开(公告)号：US20200066302A1

公开(公告)日：2020-02-27

申请号：US16609993

申请日：2018-04-13

申请人： Sony Corporation

发明人： Masaru TERAKAWA ,  Yoichi KANEMAKI ,  Minoru YAMAGA

IPC分类号： G11B5/706 ,  G11B5/66 ,  G11B5/712 ,  G11B5/714 ,  H01F1/03

摘要： Provided is a magnetic recording medium including: a recording layer containing a powder of particles containing ε iron oxide, in which a ratio ((Hc(50)/Hc(25))×100) of a coercive force Hc(50) measured in a thickness direction of the magnetic recording medium at 50° C. and a coercive force Hc(25) measured in the thickness direction of the magnetic recording medium at 25° C. is 95% or greater, the coercive force Hc(25) is 200 kA/m or greater, and a squareness ratio measured in a transport direction of the magnetic recording medium is 30% or less.

公开(公告)号：US20190066723A1

公开(公告)日：2019-02-28

申请号：US16176825

申请日：2018-10-31

申请人： Sony Corporation

发明人： Eiji NAKASHIO ,  Minoru YAMAGA ,  Masaru TERAKAWA ,  Yoichi KANEMAKI ,  Katsunori MAESHIMA ,  Jun HASHIMOTO

IPC分类号： G11B5/706 ,  G11B5/78 ,  G11B5/714 ,  G11B5/70

摘要： 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.

公开(公告)号：US20170162220A1

公开(公告)日：2017-06-08

申请号：US15316436

申请日：2015-04-10

申请人： Sony Corporation

发明人： Eiji NAKASHIO ,  Minoru YAMAGA ,  Masaru TERAKAWA ,  Yoichi KANEMAKI ,  Katsunori MAESHIMA ,  Jun HASHIMOTO

IPC分类号： G11B5/706 ,  G11B5/714 ,  G11B5/78

CPC分类号： G11B5/70642 ,  G11B5/70 ,  G11B5/70621 ,  G11B5/70678 ,  G11B5/714 ,  G11B5/78

摘要： 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.

公开(公告)号：US20200321025A1

公开(公告)日：2020-10-08

申请号：US16099298

申请日：2017-05-11

申请人： SONY CORPORATION

发明人： Eiji NAKASHIO ,  Yuta AKIMOTO ,  Tomoe SATO ,  Yoichi KANEMAKI ,  Nobuyuki SASAKI ,  Masaru TERAKAWA ,  Kazuya HASHIMOTO ,  Katsunori MAESHIMA ,  Minoru YAMAGA ,  Hikaru TERUI ,  Hiroyuki KOBAYASHI

IPC分类号： G11B5/706 ,  B32B7/022

摘要： A magnetic recording medium includes an elongated substrate, and a reinforcing layer and a carbon thin film disposed on one surface of the substrate.

公开(公告)号：US20200098390A1

公开(公告)日：2020-03-26

申请号：US16609135

申请日：2018-04-24

申请人： Sony Corporation

发明人： Masaru TERAKAWA ,  Yoichi KANEMAKI ,  Minoru YAMAGA

IPC分类号： G11B5/667 ,  G11B5/73 ,  G11B5/65 ,  H01F1/147

摘要： Provided is a magnetic recording medium having a recording track width of 2 μm or less, including: a recording layer containing a powder of particles containing ε iron oxide, in which a squareness ratio measured in a transport direction is 30% or less, a squareness ratio S1 measured in the transport direction and a squareness ratio S2 measured in a width direction satisfy a relationship S1≥S2, a coercive force is 220 kA/m or greater and 310 kA/m or less, an activation volume is 8000 nm3 or less, and in a switching field distribution (SFD) curve, a peak ratio X/Y of a main peak height X and a height Y of a sub-peak near zero magnetic field is 3.0 or greater.

公开(公告)号：US20190295584A1

公开(公告)日：2019-09-26

申请号：US16321291

申请日：2017-11-17

申请人： Sony Corporation

发明人： Masaru TERAKAWA ,  Yoichi KANEMAKI ,  Minoru YAMAGA

IPC分类号： G11B5/706 ,  G11B5/712 ,  G11B5/714

摘要： A magnetic recording medium is used in a recording/reproduction apparatus having a shortest recording wavelength of not more than 75 nm, the magnetic recording medium including a recording layer that contains a powder of particles containing ε-iron oxide, in which a squareness ratio measured in a traveling direction of the magnetic recording medium is not more than 30%, a ratio (Dmax/Dmin) of an average longest diameter Dmax of the particles to an average shortest diameter Dmin of the particles satisfies a relationship of 1.0≤(Dmax/Dmin)≤1.1, an average thickness δmag of the recording layer is not more than 100 nm, and a ratio (δmag/Dmin) of the average thickness δmag of the recording layer to the average shortest diameter Dmin of the particles satisfies a relationship of δmag/Dmin≤5.