Patents by Inventor Norihito KASADA

Norihito KASADA 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).

  • Magnetic recording medium and magnetic recording and reproducing device
    Patent number: 11189318
    Abstract: The magnetic recording medium includes a non-magnetic support, a magnetic layer including a ferromagnetic powder on one surface of the non-magnetic support, and a back coating layer including a non-magnetic powder on the other surface of the non-magnetic support, in which a difference (Safter?Sbefore) between a spacing Safter measured by optical interferometry regarding a surface of the back coating layer after methyl ethyl ketone cleaning and a spacing Sbefore measured by optical interferometry regarding the surface of the back coating layer before methyl ethyl ketone cleaning is greater than 0 nm and equal to or smaller than 30.0 nm, and the non-magnetic support is an aromatic polyamide support having a moisture absorption of 2.2% or less.
    Type: Grant
    Filed: April 23, 2020
    Date of Patent: November 30, 2021
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • MAGNETIC TAPE HAVING CHARACTERIZED MAGNETIC LAYER AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210358521
    Abstract: The magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, in which the magnetic layer includes one or more components selected from the group consisting of fatty acid and fatty acid amide, a C—H derived C concentration calculated from a C—H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on a surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is equal to or greater than 45 atom %, and an absolute value ?N of a difference between a refractive index Nxy measured regarding an in-plane direction of the magnetic layer and a refractive index Nz measured regarding a thickness direction of the magnetic layer is 0.25 to 0.40.
    Type: Application
    Filed: July 28, 2021
    Publication date: November 18, 2021
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • MAGNETIC TAPE HAVING CHARACTERIZED MAGNETIC LAYER AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210335387
    Abstract: The magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, in which an absolute value ?N of a difference between a refractive index Nxy measured regarding an in-plane direction of the magnetic layer and a refractive index Nz measured regarding a thickness direction of the magnetic layer is 0.25 to 0.40, and a logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding a surface of the magnetic layer is equal to or smaller than 0.050.
    Type: Application
    Filed: July 6, 2021
    Publication date: October 28, 2021
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Magnetic tape with particular refractive index characteristics, magnetic tape cartridge, and magnetic tape apparatus
    Patent number: 11145325
    Abstract: Provided are a magnetic tape including: a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, in which a total thickness of the magnetic tape is equal to or smaller than 5.30 ?m, the magnetic layer has a servo pattern, a center line average surface roughness Ra measured on a surface of the magnetic layer is equal to or smaller than 1.8 nm, and an absolute value ?N of a difference between a refractive index Nxy of the magnetic layer, measured in an in-plane direction and a refractive index Nz of the magnetic layer, measured in a thickness direction is 0.25 to 0.40, a magnetic tape cartridge and a magnetic tape apparatus including this magnetic tape, a magnetic tape cartridge and a magnetic tape apparatus including this magnetic tape.
    Type: Grant
    Filed: December 26, 2019
    Date of Patent: October 12, 2021
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
    Publication number: 20210295865
    Abstract: The magnetic tape includes a non-magnetic support; and a magnetic layer, in which the magnetic layer has a timing-based servo pattern, an edge shape of the timing-based servo pattern, specified by magnetic force microscopy is a shape in which a difference L99.9?L0.1 between a value L99.9 of a cumulative distribution function of 99.9% and a value L0.1 of a cumulative distribution function of 0.1% in a position deviation width from an ideal shape of the magnetic tape in a longitudinal direction is 180 nm or less, and an absolute value ?N of a difference between a refractive index Nxy of the magnetic layer, measured in an in-plane direction and a refractive index Nz of the magnetic layer, measured in a thickness direction is 0.25 or more and 0.40 or less.
    Type: Application
    Filed: May 26, 2021
    Publication date: September 23, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki OZAWA, Atsushi MUSHA
  • Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus
    Patent number: 11127428
    Abstract: The magnetic tape includes a non-magnetic support and a magnetic layer, in which an edge shape of the timing-based servo pattern, specified by magnetic force microscopy is a shape in which a difference between a value L99.9 of a cumulative distribution function of 99.9% and a value L0.1 of a cumulative distribution function of 0.1% in a position deviation width from an ideal shape of the magnetic tape in a longitudinal direction is 180 nm or less, and in which a difference between a spacing Safter measured on a surface of the magnetic layer by an optical interferometry after ethanol cleaning and a spacing Sbefore measured on the surface of the magnetic layer by an optical interferometry before ethanol cleaning is greater than 0 nm and 6.0 nm or less.
    Type: Grant
    Filed: January 30, 2020
    Date of Patent: September 21, 2021
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada, Atsushi Musha
  • MAGNETIC RECORDING MEDIUM, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210287705
    Abstract: The magnetic recording medium includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder in which the ferromagnetic powder is ?-iron oxide powder, and an anisotropic magnetic field Hk of the magnetic recording medium measured after pressing the magnetic layer at a pressure of 70 atm is 15,000 Oe to 40,000 Oe.
    Type: Application
    Filed: March 8, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki OZAWA, Takashi FUJIMOTO
  • MAGNETIC RECORDING MEDIUM, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210287703
    Abstract: The magnetic recording medium includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which the ferromagnetic powder is an ?-iron oxide powder, and a transition temperature Tc of the magnetic recording medium measured after pressing the magnetic layer at a pressure of 70 atm is 80° C. to 240° C.
    Type: Application
    Filed: March 9, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Eiki OZAWA, Norihito Kasada, Takashi Fujimoto
  • MAGNETIC RECORDING MEDIUM, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210287706
    Abstract: The magnetic recording medium includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder in which the ferromagnetic powder is ?-iron oxide powder, and a coefficient of friction measured on a base part of a surface of the magnetic layer after pressing the magnetic layer at a pressure of 90 atm is 0.35 or less.
    Type: Application
    Filed: March 9, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Megumi Nakano, Eiki Ozawa, Norihito Kasada
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS
    Publication number: 20210287711
    Abstract: The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder, in which the ferromagnetic powder is ?-iron oxide powder, and a coefficient of variation of particle size of the ?-iron oxide powder in a longitudinal direction of the magnetic layer is 0.50% or more and 5.00% or less.
    Type: Application
    Filed: March 12, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Takashi FUJIMOTO, Norihito KASADA, Eiki OZAWA
  • MAGNETIC TAPE HAVING CHARACTERIZED MAGNETIC LAYER AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210287712
    Abstract: Provided are a magnetic tape comprising a magnetic layer containing a ferromagnetic powder and a binding agent on a non-magnetic support, in which the magnetic layer contains an oxide abrasive, an average particle diameter of the oxide abrasive obtained from a secondary ion image acquired by irradiating a surface of the magnetic layer with a focused ion beam is 0.04 ?m to 0.08 ?m, and an absolute value ?N of a difference between a refractive index Nxy measured with respect to an in-plane direction of the magnetic layer and a refractive index Nz measured with respect to a thickness direction of the magnetic layer is 0.25 to 0.40, and a magnetic recording and reproducing device including the magnetic tape.
    Type: Application
    Filed: May 21, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Takahiro IWAMOTO, Hidemasa Hosoda, Norihito Kasada, Takuto Kurokawa
  • MAGNETIC RECORDING MEDIUM, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210287713
    Abstract: The magnetic recording medium includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder in which the ferromagnetic powder is ?-iron oxide powder, and a vertical magnetization amount ?m per unit area of the magnetic recording medium measured after pressing the magnetic layer at a pressure of 70 atm is 8.0 G·?m to 80.0 G·?m.
    Type: Application
    Filed: March 8, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki Ozawa, Takashi Fujimoto
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS
    Publication number: 20210287704
    Abstract: The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder, in which the ferromagnetic powder is ?-iron oxide powder, and a coefficient of variation of an anisotropic magnetic field Hk in a longitudinal direction of the magnetic tape is 2.0% or more and 10.0% or less.
    Type: Application
    Filed: March 10, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada, Takashi Fujimoto
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
    Publication number: 20210287702
    Abstract: The magnetic tape includes a non-magnetic support and a magnetic layer, in which an edge shape of the timing-based servo pattern, specified by magnetic force microscopy is a shape in which a difference between a value L99.9 of a cumulative distribution function of 99.9% and a value L0.1 of a cumulative distribution function of 0.1% in a position deviation width from an ideal shape of the magnetic tape in a longitudinal direction is 180 nm or less, and in which a difference between a spacing Safter measured on a surface of the magnetic layer by an optical interferometry after ethanol cleaning and a spacing Sbefore measured on the surface of the magnetic layer by an optical interferometry before ethanol cleaning is greater than 0 nm and 6.0 nm or less.
    Type: Application
    Filed: May 25, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Eiki OZAWA, Norihito KASADA, Atsushi MUSHA
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS
    Publication number: 20210287710
    Abstract: The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder, in which the ferromagnetic powder is ?-iron oxide powder, and a coefficient of variation of aspect ratio of the ?-iron oxide powder in a longitudinal direction of the magnetic layer is 0.20% or more and 8.00% or less.
    Type: Application
    Filed: March 12, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Takashi Fujimoto, Norihito Kasada, Eiki Ozawa
  • MAGNETIC RECORDING MEDIUM, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210287708
    Abstract: The magnetic recording medium includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder in which the ferromagnetic powder is an ?-iron oxide powder, and a vertical squareness ratio of the magnetic recording medium measured after pressing the magnetic layer at a pressure of 70 atm is 0.50 to 0.95.
    Type: Application
    Filed: March 9, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Eiki OZAWA, Norihito KASADA, Takashi FUJIMOTO
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS
    Publication number: 20210287709
    Abstract: The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder, in which the ferromagnetic powder is ?-iron oxide powder, and a coefficient of variation of particle size of the ?-iron oxide powder in a longitudinal direction of the magnetic layer is more than 5.00% and 15.00% or less.
    Type: Application
    Filed: March 9, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Takashi FUJIMOTO, Norihito KASADA, Eiki OZAWA
  • MAGNETIC RECORDING MEDIUM, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210287707
    Abstract: The magnetic recording medium includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder in which the ferromagnetic powder is c-iron oxide powder, and a coercivity of a magnetic recording medium in a vertical direction measured after pressing the magnetic layer at a pressure of 70 atm is 3,000 Oe to 10,000 Oe.
    Type: Application
    Filed: March 9, 2021
    Publication date: September 16, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki OZAWA, Takashi FUJIMOTO
  • MAGNETIC TAPE WITH PARTICULAR REFRACTIVE INDEX CHARACTERISTICS, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
    Publication number: 20210280212
    Abstract: Provided are a magnetic tape including: a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, in which a total thickness of the magnetic tape is equal to or smaller than 5.30 ?m, the magnetic layer has a servo pattern, a center line average surface roughness Ra measured on a surface of the magnetic layer is equal to or smaller than 1.8 nm, and an absolute value ?N of a difference between a refractive index Nxy of the magnetic layer, measured in an in-plane direction and a refractive index Nz of the magnetic layer, measured in a thickness direction is 0.25 to 0.40, a magnetic tape cartridge and a magnetic tape apparatus including this magnetic tape, a magnetic tape cartridge and a magnetic tape apparatus including this magnetic tape.
    Type: Application
    Filed: May 24, 2021
    Publication date: September 9, 2021
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • MAGNETIC TAPE DEVICE, MAGNETIC TAPE, AND MAGNETIC TAPE CARTRIDGE
    Publication number: 20210257001
    Abstract: A magnetic tape device, a magnetic tape, and a magnetic tape cartridge, in which the magnetic tape is caused to run between a winding reel and a cartridge reel in a state where a tension is applied in a longitudinal direction of the magnetic tape and a maximum value of the tension is 0.50 N or more, the magnetic tape after running in a state where the tension is applied is wound around the cartridge reel by applying a tension of 0.40 N or less in the longitudinal direction, and a center line average roughness Ra measured regarding a surface of a back coating layer of the magnetic tape with an atomic force microscope is in a range of 5 to 13 nm.
    Type: Application
    Filed: February 4, 2021
    Publication date: August 19, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Yusuke KANEKO, Yuto MURATA, Norihito KASADA