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 tape having characterized magnetic layer and magnetic recording and reproducing device
    Patent number: 11094343
    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: Grant
    Filed: March 22, 2019
    Date of Patent: August 17, 2021
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
    Publication number: 20210249043
    Abstract: The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder and a binding agent, 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 isoelectric point of a surface zeta potential of the magnetic layer is 3.8 or less.
    Type: Application
    Filed: April 28, 2021
    Publication date: August 12, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa, Atsushi Musha
  • Magnetic tape with particular refractive index characteristics, magnetic tape cartridge, and magnetic tape apparatus
    Patent number: 11087793
    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: August 10, 2021
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus
    Patent number: 11087787
    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: Grant
    Filed: January 30, 2020
    Date of Patent: August 10, 2021
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa, Atsushi Musha
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
    Publication number: 20210241787
    Abstract: The magnetic tape satisfies TDSage+TDSenv?TC?0.30 ?m. TDSage is a maximum absolute value of a difference between the servo band interval obtained before a predetermined storage and the servo band interval obtained after the storage, TDSenv is a value calculated by multiplying a difference between a maximum value and a minimum value of the servo band interval respectively obtained under five predetermined environments by ½, TC is a value calculated by multiplying TDStens by 0.5 N, and TDStens is a ratio of a change in the servo band interval to a change in tension calculated from the servo band interval respectively obtained under five predetermined environments by applying a plurality of different tensions in the longitudinal direction of the magnetic tape.
    Type: Application
    Filed: January 28, 2021
    Publication date: August 5, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Yuto MURATA, Yusuke Kaneko, Norihito Kasada
  • MAGNETIC TAPE CARTRIDGE AND MAGNETIC TAPE APPARATUS
    Publication number: 20210241786
    Abstract: The magnetic tape cartridge includes a magnetic tape that is accommodated in the magnetic tape cartridge while being wound around a reel hub. The magnetic tape has a non-magnetic support and a magnetic layer including ferromagnetic powder, and includes one or more components selected from the group consisting of a fatty acid and a fatty acid amide in a portion on the magnetic layer side on the non-magnetic support, and after the magnetic tape cartridge is stored in an environment of an atmosphere temperature of 60° C. and a relative humidity of 80% for 24 hours, 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 at a photoelectron take-off angle of 10 degrees on a surface of the magnetic layer in an inner region during winding of the magnetic tape is 45 at % or more.
    Type: Application
    Filed: January 28, 2021
    Publication date: August 5, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Yosuke Sumiya
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
    Publication number: 20210241795
    Abstract: In the probability distribution calculated from TDSage, TDSenv, and TC, the magnetic tape has the probability Pfail of equal to or less than 0.2%, in which the absolute value of ?SB exceeds 0.3 ?m. TDSage is a maximum absolute value of a difference between the servo band interval obtained before a predetermined storage and the servo band interval obtained after the storage, TDSenv is a value calculated by multiplying a difference between a maximum value and a minimum value of the servo band interval respectively obtained under five predetermined environments by ½, TC is a value calculated by multiplying TDStens by 0.5 N, and TDStens is a ratio of a change in the servo band interval to a change in tension calculated from the servo band interval respectively obtained under five predetermined environments by applying a plurality of different tensions in the longitudinal direction of the magnetic tape.
    Type: Application
    Filed: January 28, 2021
    Publication date: August 5, 2021
    Inventors: Yuto MURATA, Yusuke KANEKO, Norihito KASADA
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
    Publication number: 20210241792
    Abstract: The magnetic tape in which a difference (S0.1?S1.6) between a spacing S0.1 and a spacing S1.6 obtained after n-hexane cleaning on a surface of the magnetic layer is equal to or less than 32 nm. The S0.1 is a value obtained as a spacing under a pressing force of 0.1 atm from a relational expression between a pressure and a spacing obtained by performing a spacing measurement on the surface of the magnetic layer by an optical interference method under a pressing force of each of a plurality of different pressures after the n-hexane cleaning, and S1.6 is a spacing measured on the surface of the magnetic layer by the optical interference method under the pressing force of 1.6 atm after the n-hexane cleaning.
    Type: Application
    Filed: January 28, 2021
    Publication date: August 5, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Takuto KUROKAWA, Naoki SANO, Norihito KASADA
  • MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING AND REPRODUCING APPARATUS, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE CARTRIDGE GROUP
    Publication number: 20210233564
    Abstract: In the magnetic recording medium, a number distribution A of a plurality of bright regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 5 kV and a number distribution B of a plurality of dark regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 2 kV respectively satisfy a predetermined number distribution.
    Type: Application
    Filed: January 22, 2021
    Publication date: July 29, 2021
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING AND REPRODUCING APPARATUS, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE CARTRIDGE GROUP
    Publication number: 20210233561
    Abstract: In the magnetic recording medium, a number distribution A of a plurality of bright regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 5 kV and a number distribution B of a plurality of dark regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 2 kV respectively satisfy a predetermined number distribution.
    Type: Application
    Filed: January 22, 2021
    Publication date: July 29, 2021
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING AND REPRODUCING APPARATUS, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE CARTRIDGE GROUP
    Publication number: 20210233565
    Abstract: In the magnetic recording medium, a number distribution A of a plurality of bright regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 5 kV and a number distribution B of a plurality of dark regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 2 kV respectively satisfy a predetermined number distribution.
    Type: Application
    Filed: January 22, 2021
    Publication date: July 29, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, So MATSUYAMA, Atsushi MUSHA, Shota KAMIMURA
  • MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING AND REPRODUCING APPARATUS, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE CARTRIDGE GROUP
    Publication number: 20210233562
    Abstract: In the magnetic recording medium, a number distribution A of a plurality of bright regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 5 kV and a number distribution B of a plurality of dark regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 2 kV respectively satisfy a predetermined number distribution.
    Type: Application
    Filed: January 21, 2021
    Publication date: July 29, 2021
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING AND REPRODUCING APPARATUS, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE CARTRIDGE GROUP
    Publication number: 20210233566
    Abstract: In the magnetic recording medium, a number distribution A of a plurality of bright regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 5 kV and a number distribution B of a plurality of dark regions, based on equivalent circle diameters thereof, in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer by a scanning electron microscope at an acceleration voltage of 2 kV respectively satisfy a predetermined number distribution.
    Type: Application
    Filed: January 22, 2021
    Publication date: July 29, 2021
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20210233563
    Abstract: In the magnetic recording and reproducing device, a distal end width of the first magnetic pole in the recording element is substantially the same as a distal end width of the second magnetic pole; the reproducing element width of the reproducing element is equal to or less than 0.8 ?m; and in the magnetic recording medium, a number distribution A of equivalent circle diameters of a plurality of bright areas in a binarized image of a secondary electron image obtained by imaging a surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 5 kV, and a number distribution B of equivalent circle diameters of a plurality of dark areas in a binarized image of a secondary electron image obtained by imaging the surface of the magnetic layer with a scanning electron microscope at an acceleration voltage of 2 kV satisfy predetermined number distribution, respectively.
    Type: Application
    Filed: January 22, 2021
    Publication date: July 29, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Atsushi MUSHA, So MATSUYAMA, Norihito KASADA
  • Magnetic tape having characterized magnetic layer and magnetic recording and reproducing device
    Patent number: 11069377
    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: Grant
    Filed: March 27, 2020
    Date of Patent: July 20, 2021
    Assignee: FUJIFILM Corporation
    Inventors: Takahiro Iwamoto, Hidemasa Hosoda, Norihito Kasada, Takuto Kurokawa
  • Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus
    Patent number: 11056141
    Abstract: The magnetic tape includes a non-magnetic support and a magnetic layer including ferromagnetic powder and a binding agent, 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 isoelectric point of a surface zeta potential of the magnetic layer is 3.8 or less.
    Type: Grant
    Filed: January 30, 2020
    Date of Patent: July 6, 2021
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa, Atsushi Musha
  • MAGNETIC TAPE, MAGNETIC TAPE CARTRIDGE, AND MAGNETIC TAPE APPARATUS
    Publication number: 20210201945
    Abstract: A magnetic tape in which a minimum value of TDStens among five TDStens measured respectively at a temperature of 16° C. and a relative humidity of 20%, a temperature of 16° C. and a relative humidity of 80%, a temperature of 26° C. and a relative humidity of 80%, a temperature of 32° C. and a relative humidity of 20% and a temperature of 32° C. and a relative humidity of 55% is 1.43 ?m/N or more, a ratio of a change of TDStens to a change of a relative humidity obtained from the five TDStens is 0.005 ?m/N/% or less, and a ratio of a change of TDStens to a change of a temperature obtained from the five TDStens is 0.020 ?m/N/° C. or less.
    Type: Application
    Filed: December 22, 2020
    Publication date: July 1, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Yuto Murata, Yusuke Kaneko
  • Magnetic recording medium having characterized magnetic layer and magnetic recording and reproducing device
    Patent number: 10978105
    Abstract: Provided are a magnetic recording medium, in which a magnetic layer includes a ferromagnetic hexagonal ferrite powder, a binding agent, and an oxide abrasive, an intensity ratio Int(110)/Int(114) obtained by an X-ray diffraction analysis of the magnetic layer by using an In-Plane method is 0.5 to 4.0, a vertical squareness ratio of the magnetic recording medium is 0.65 to 1.00, a contact angle with respect to 1-bromonaphthalene measured regarding a surface of the magnetic layer is 50.0° to 55.0°, and an average particle diameter of the oxide abrasive obtained from a secondary ion image obtained by irradiating the surface of the magnetic layer with a focused ion beam is 0.04 ?m to 0.08 ?m, and a magnetic recording and reproducing device including this magnetic recording medium.
    Type: Grant
    Filed: September 27, 2018
    Date of Patent: April 13, 2021
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada
  • MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING AND REPRODUCING APPARATUS
    Publication number: 20210090602
    Abstract: The magnetic recording medium includes: a non-magnetic support; a magnetic layer that includes ferromagnetic powder on one surface side of the non-magnetic support; and a back coating layer that includes non-magnetic powder on the other surface side of the non-magnetic support, in which a difference between a spacing measured on a surface of the back coating layer by optical interferometry under a pressure of 0.5 atm after n-hexane cleaning and a spacing measured on the surface of the back coating layer by optical interferometry under a pressure of 13.5 atm after n-hexane cleaning is 12 nm or more.
    Type: Application
    Filed: September 18, 2020
    Publication date: March 25, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Naoki SANO, Takuto KUROKAWA, Eiki OZAWA, Norihito KASADA, Megumi NAKANO
  • MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING AND REPRODUCING APPARATUS
    Publication number: 20210090600
    Abstract: The magnetic recording medium includes a non-magnetic support; a magnetic layer that includes ferromagnetic powder on one surface side of the non-magnetic support; and a back coating layer that includes non-magnetic powder on the other surface side of the non-magnetic support, in which a difference between a spacing measured on a surface of the back coating layer by optical interferometry under a pressure of 0.5 atm after n-hexane cleaning and a spacing measured on the surface of the back coating layer by optical interferometry under a pressure of 13.5 atm after n-hexane cleaning is 3 nm or less.
    Type: Application
    Filed: September 16, 2020
    Publication date: March 25, 2021
    Applicant: FUJIFILM Corporation
    Inventors: Takuto KUROKAWA, Naoki SANO, Norihito KASADA, Eiki OZAWA, Megumi NAKANO