Patents by Inventor Katsunori Maeshima

Katsunori Maeshima has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 11355145
    Abstract: 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.
    Type: Grant
    Filed: December 14, 2016
    Date of Patent: June 7, 2022
    Assignee: Sony Corporation
    Inventors: Eiji Nakashio, Masaru Terakawa, Yoichi Kanemaki, Tomoe Sato, Katsunori Maeshima, Nobuyuki Sasaki
  • Publication number: 20220139423
    Abstract: [Solving Means] A tape-shaped magnetic recording medium includes: a base; and a magnetic layer that is provided on the base and includes a magnetic powder. The magnetic powder includes magnetic particles that have a uniaxial crystal magnetic anisotropy and contain cobalt ferrite. A ratio L4/L2 of a component L4 having a multiaxial crystal magnetic anisotropy to a component L2 having a uniaxial crystal magnetic anisotropy is 0 or more and 0.25 or less, the components being obtained by applying Fourier transformation to a torque waveform of the magnetic recording medium.
    Type: Application
    Filed: February 14, 2020
    Publication date: May 5, 2022
    Inventors: Takashi KATAGUCHI, Masaru TERAKAWA, Takeshi TAKAHASHI, Natsuki ICHISE, Katsunori MAESHIMA
  • Patent number: 11270729
    Abstract: A tape-shaped magnetic recording medium includes a base, a nonmagnetic layer that is provided on the base and contains a nonmagnetic powder, and a magnetic layer that is provided on the nonmagnetic layer and contains a magnetic powder. In the magnetic recording medium, the magnetic layer has an average thickness of not more than 90 nm, the magnetic powder has an average aspect ratio of from 1.0 to 3.0, a coercive force Hc1 in a perpendicular direction is not more than 3,000 Oe, the coercive force Hc1 in the perpendicular direction and a coercive force Hc2 in a longitudinal direction satisfy the relation of Hc2/Hc1?0.8, the nonmagnetic layer has an average thickness of not more than 1.1 ?m, and the nonmagnetic powder has an average particle volume of not more than 2.0×10?5 ?m3.
    Type: Grant
    Filed: April 1, 2019
    Date of Patent: March 8, 2022
    Assignee: Sony Corporation
    Inventors: Masaru Terakawa, Minoru Yamaga, Katsunori Maeshima
  • Publication number: 20220036919
    Abstract: [Object] A cobalt ferrite magnetic powder includes magnetic particles that have a uniaxial crystal magnetic anisotropy and contain cobalt ferrite. A peak top 2? of a (3, 1, 1) plane determined by powder X-ray diffractometry using a CoK? ray is 41.3° or more and 41.5° or less. Some Cos contained in the magnetic particles are substituted with at least one selected from the group consisting of Zn, Ge, and a transition metal element other than Fe.
    Type: Application
    Filed: February 14, 2020
    Publication date: February 3, 2022
    Inventors: Natsuki ICHISE, Masaru TERAKAWA, Katsunori MAESHIMA, Takashi KATAGUCHI, Takeshi TAKAHASHI
  • Patent number: 11205455
    Abstract: A tape-shaped magnetic recording medium includes a substrate; and a magnetic layer that is provided on the substrate and contains a magnetic powder. An average thickness of the magnetic layer is not more than 90 nm, an average aspect ratio of the magnetic powder is not less than 1.0 and not more than 3.0, the coercive force Hc1 in a vertical direction is not more than 3000 Oe, and the coercive force Hc1 in the vertical direction and a coercive force Hc2 in a longitudinal direction satisfy a relationship of Hc2/Hc1?0.8.
    Type: Grant
    Filed: November 19, 2018
    Date of Patent: December 21, 2021
    Assignee: Sony Corporation
    Inventors: Masaru Terakawa, Minoru Yamaga, Katsunori Maeshima
  • Patent number: 11170813
    Abstract: A method of producing a magnetic powder includes performing heat treatment on first particles that contain ferrous oxide to prepare 5 second particles that contain ?-iron oxide.
    Type: Grant
    Filed: September 27, 2017
    Date of Patent: November 9, 2021
    Assignee: Sony Corporation
    Inventors: Atsushi Muramatsu, Masafumi Nakaya, Masaru Terakawa, Katsunori Maeshima, Minoru Yamaga
  • Patent number: 11145328
    Abstract: A tape-shaped magnetic recording medium includes a substrate; and a magnetic layer that is provided on the substrate and contains a magnetic powder. An average thickness of the magnetic layer is not more than 90 nm, an average aspect ratio of the magnetic powder is not less than 1.0 and not more than 3.0, the coercive force Hc1 in a vertical direction is not more than 3000 Oe, the coercive force Hc1 in the vertical direction and a coercive force Hc2 in a longitudinal direction satisfy a relationship of Hc2/Hc1?0.8, and a value of ?1.5??0.5 is not more than 0.6 N in a tensile test of the magnetic recording medium in the longitudinal direction, where ?0.5 is a load at an elongation rate of 0.5% in the magnetic recording medium and ?1.5 is a load at an elongation rate of 1.5% in the magnetic recording medium.
    Type: Grant
    Filed: August 13, 2020
    Date of Patent: October 12, 2021
    Assignee: Sony Corporation
    Inventors: Masaru Terakawa, Minoru Yamaga, Katsunori Maeshima
  • Publication number: 20210287714
    Abstract: A method of producing a magnetic powder includes: performing heat treatment on first particles that contain triiron tetraoxide to prepare second particles that contain ?-iron oxide.
    Type: Application
    Filed: September 27, 2017
    Publication date: September 16, 2021
    Inventors: Atsushi MURAMATSU, Masafumi NAKAYA, Masaru TERAKAWA, Satoru ABE, Natsuki TOYOSAWA, Katsunori MAESHIMA
  • Publication number: 20210027807
    Abstract: [Solving Means] A method of producing a magnetic powder includes: coating a surface of each of silica-coated precursor particles with at least one type of coating agent of a metal chloride or a sulfate; and firing the precursor particles coated with the coating agent.
    Type: Application
    Filed: March 27, 2019
    Publication date: January 28, 2021
    Inventors: Natsuki TOYOSAWA, Norikatsu FUJISAWA, Yuta AKIMOTO, Satoru ABE, Masaru TERAKAWA, Katsunori MAESHIMA, Atsushi MURAMATU, Masashi NAKATANI
  • Publication number: 20210020197
    Abstract: A tape-shaped magnetic recording medium includes a base, a nonmagnetic layer that is provided on the base and contains a nonmagnetic powder, and a magnetic layer that is provided on the nonmagnetic layer and contains a magnetic powder. In the magnetic recording medium, the magnetic layer has an average thickness of not more than 90 nm, the magnetic powder has an average aspect ratio of from 1.0 to 3.0, a coercive force Hc1 in a perpendicular direction is not more than 3,000 Oe, the coercive force Hc1 in the perpendicular direction and a coercive force Hc2 in a longitudinal direction satisfy the relation of Hc2/Hc1?0.8, the nonmagnetic layer has an average thickness of not more than 1.1 ?m, and the nonmagnetic powder has an average particle volume of not more than 2.0×10?5 ?m3.
    Type: Application
    Filed: April 1, 2019
    Publication date: January 21, 2021
    Inventors: Masaru TERAKAWA, Minoru YAMAGA, Katsunori MAESHIMA
  • Publication number: 20210012799
    Abstract: A tape-shaped magnetic recording medium includes a substrate; and a magnetic layer that is provided on the substrate and contains a magnetic powder. An average thickness of the magnetic layer is not more than 90 nm, an average aspect ratio of the magnetic powder is not less than 1.0 and not more than 3.0, the coercive force Hc1 in a vertical direction is not more than 3000 Oe, and the coercive force Hc1 in the vertical direction and a coercive force Hc2 in a longitudinal direction satisfy a relationship of Hc2/Hc1?0.8.
    Type: Application
    Filed: November 19, 2018
    Publication date: January 14, 2021
    Inventors: Masaru TERAKAWA, Minoru YAMAGA, Katsunori MAESHIMA
  • Patent number: 10872633
    Abstract: 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.
    Type: Grant
    Filed: May 11, 2017
    Date of Patent: December 22, 2020
    Assignee: Sony Corporation
    Inventors: Eiji Nakashio, Yuta Akimoto, Tomoe Sato, Yoichi Kanemaki, Nobuyuki Sasaki, Masaru Terakawa, Kazuya Hashimoto, Katsunori Maeshima, Minoru Yamaga, Hikaru Terui, Hiroyuki Kobayashi
  • Publication number: 20200372932
    Abstract: A tape-shaped magnetic recording medium includes a substrate; and a magnetic layer that is provided on the substrate and contains a magnetic powder. An average thickness of the magnetic layer is not more than 90 nm, an average aspect ratio of the magnetic powder is not less than 1.0 and not more than 3.0, the coercive force Hc1 in a vertical direction is not more than 3000 Oe, the coercive force Hc1 in the vertical direction and a coercive force Hc2 in a longitudinal direction satisfy a relationship of Hc2/Hc1?0.8, and a value of ?1.5??0.5 is not more than 0.6 N in a tensile test of the magnetic recording medium in the longitudinal direction, where ?0.5 is a load at an elongation rate of 0.5% in the magnetic recording medium and ?1.5 is a load at an elongation rate of 1.5% in the magnetic recording medium.
    Type: Application
    Filed: August 13, 2020
    Publication date: November 26, 2020
    Inventors: Masaru TERAKAWA, Minoru YAMAGA, Katsunori MAESHIMA
  • Patent number: 10839848
    Abstract: 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 ?-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.
    Type: Grant
    Filed: October 31, 2018
    Date of Patent: November 17, 2020
    Assignee: Sony Corporation
    Inventors: Eiji Nakashio, Minoru Yamaga, Masaru Terakawa, Yoichi Kanemaki, Katsunori Maeshima, Jun Hashimoto
  • Publication number: 20200321025
    Abstract: A magnetic recording medium includes an elongated substrate, and a reinforcing layer and a carbon thin film disposed on one surface of the substrate.
    Type: Application
    Filed: May 11, 2017
    Publication date: October 8, 2020
    Applicant: Sony Corporation
    Inventors: Eiji NAKASHIO, Yuta AKIMOTO, Tomoe SATO, Yoichi KANEMAKI, Nobuyuki SASAKI, Masaru TERAKAWA, Kazuya HASHIMOTO, Katsunori MAESHIMA, Minoru YAMAGA, Hikaru TERUI, Hiroyuki KOBAYASHI
  • Patent number: 10783914
    Abstract: A magnetic recording medium includes: a substrate; and a magnetic layer including a ferrimagnetic particle powder. A product (V×SFD) of a particle volume V and a holding force distribution SFD of the ferrimagnetic particle is equal to or less than 2500 nm3.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: September 22, 2020
    Assignee: Sony Corporation
    Inventor: Katsunori Maeshima
  • Patent number: 10748570
    Abstract: A tape-shaped magnetic recording medium includes a substrate; and a magnetic layer that is provided on the substrate and contains a magnetic powder. An average thickness of the magnetic layer is not more than 90 nm, an average aspect ratio of the magnetic powder is not less than 1.0 and not more than 3.0, the coercive force Hc1 in a vertical direction is not more than 3000 Oe, the coercive force Hc1 in the vertical direction and a coercive force Hc2 in a longitudinal direction satisfy a relationship of Hc2/Hc1?0.8, and a value of ?1.5??0.5 is not more than 0.6 N in a tensile test of the magnetic recording medium in the longitudinal direction, where ?0.5 is a load at an elongation rate of 0.5% in the magnetic recording medium and ?1.5 is a load at an elongation rate of 1.5% in the magnetic recording medium.
    Type: Grant
    Filed: April 1, 2019
    Date of Patent: August 18, 2020
    Assignee: Sony Corporation
    Inventors: Masaru Terakawa, Minoru Yamaga, Katsunori Maeshima
  • Publication number: 20200118589
    Abstract: A tape-shaped magnetic recording medium includes a substrate; and a magnetic layer that is provided on the substrate and contains a magnetic powder. An average thickness of the magnetic layer is not more than 90 nm, an average aspect ratio of the magnetic powder is not less than 1.0 and not more than 3.0, the coercive force Hc1 in a vertical direction is not more than 3000 Oe, the coercive force Hc1 in the vertical direction and a coercive force Hc2 in a longitudinal direction satisfy a relationship of Hc2/Hc1?0.8, and a value of ?1.5-?0.5 is not more than 0.6 N in a tensile test of the magnetic recording medium in the longitudinal direction, where ?0.5 is a load at an elongation rate of 0.5% in the magnetic recording medium and ?1.5 is a load at an elongation rate of 1.5% in the magnetic recording medium.
    Type: Application
    Filed: April 1, 2019
    Publication date: April 16, 2020
    Inventors: Masaru TERAKAWA, Minoru YAMAGA, Katsunori MAESHIMA
  • Publication number: 20190228800
    Abstract: A method of producing a magnetic powder includes performing heat treatment on first particles that contain ferrous oxide to prepare second particles that contain ?-iron oxide.
    Type: Application
    Filed: September 27, 2017
    Publication date: July 25, 2019
    Inventors: Atsushi MURAMATSU, Masafumi NAKAYA, Masaru TERAKAWA, Katsunori MAESHIMA, Minoru YAMAGA
  • Publication number: 20190143637
    Abstract: 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.
    Type: Application
    Filed: May 11, 2017
    Publication date: May 16, 2019
    Inventors: Eiji NAKASHIO, Yuta AKIMOTO, Tomoe SATO, Yoichi KANEMAKI, Nobuyuki SASAKI, Masaru TERAKAWA, Kazuya HASHIMOTO, Katsunori MAESHIMA, Minoru YAMAGA, Hikaru TERUI, Hiroyuki KOBAYASHI