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 device and magnetic reproducing method
    Patent number: 10325623
    Abstract: The magnetic tape device includes: a magnetic tape; and a reproducing head, in which a magnetic tape transportation speed of the magnetic tape device is equal to or lower than 18 m/sec, the reproducing head is a magnetic head including a tunnel magnetoresistance effect type element as a reproducing element, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, and a coefficient of friction measured regarding a base portion of a surface of the magnetic layer is equal to or smaller than 0.30.
    Type: Grant
    Filed: December 26, 2017
    Date of Patent: June 18, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa, Tetsuya Kaneko
  • Magnetic tape having characterized magnetic layer and magnetic tape device
    Patent number: 10311909
    Abstract: A magnetic tape includes a non-magnetic layer containing non-magnetic powder and a binder on a non-magnetic support; and a magnetic layer containing ferromagnetic powder and a binder on the non-magnetic layer. The total thickness of the non-magnetic layer and the magnetic layer is equal to or less than 0.60 ?m. The magnetic layer includes a timing-based servo pattern. One or more components selected from a fatty acid and a fatty acid amide are included in at least the magnetic layer. The C—H derived C concentration calculated from the C—H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is equal to or greater than 45 atom %.
    Type: Grant
    Filed: June 19, 2017
    Date of Patent: June 4, 2019
    Assignee: FUJIFIRM Corporation
    Inventors: Norihito Kasada, Tetsuya Kaneko, Eiki Ozawa
  • Magnetic tape device with TMR head and specific logarithmic decrement and magnetic reproducing method
    Patent number: 10304486
    Abstract: The magnetic tape device includes: a magnetic tape; and a reproducing head, in which the reproducing head is a magnetic head including a tunnel magnetoresistance effect type element as a reproducing element, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, and logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is equal to or smaller than 0.050.
    Type: Grant
    Filed: December 20, 2017
    Date of Patent: May 28, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa, Tetsuya Kaneko
  • MAGNETIC TAPE DEVICE AND HEAD TRACKING SERVO METHOD
    Publication number: 20190130936
    Abstract: The magnetic tape device includes: a magnetic tape; and a servo head, in which a magnetic tape transportation speed of the magnetic tape device is equal to or lower than 18 m/sec, the servo head is a magnetic head including a tunnel magnetoresistance effect type element as a servo pattern reading element, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support, the magnetic layer includes a servo pattern, and a coefficient of friction measured regarding a base portion of a surface of the magnetic layer is equal to or smaller than 0.30.
    Type: Application
    Filed: December 26, 2018
    Publication date: May 2, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Tetsuya KANEKO, Norihito KASADA, Eiki OZAWA
  • MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20190103133
    Abstract: Provided are a magnetic recording medium, in which a magnetic layer includes a ferromagnetic hexagonal ferrite powder, a binding agent, 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 is 0.65 to 1.00, one or more kinds of component selected from the group consisting of fatty acid and fatty acid amide is contained in a magnetic layer side portion on the non-magnetic support, a C—H derived C concentration of the magnetic layer is 45 atom % to 65 atom %, 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: Application
    Filed: September 27, 2018
    Publication date: April 4, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Eiki OZAWA, Norihito KASADA
  • MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20190103131
    Abstract: Provided are a magnetic recording medium, in which a magnetic layer includes 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 logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding a surface of the magnetic layer is equal to or smaller than 0.050, 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: Application
    Filed: September 27, 2018
    Publication date: April 4, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki OZAWA
  • MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20190103135
    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: Application
    Filed: September 27, 2018
    Publication date: April 4, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Eiki OZAWA, Norihito KASADA
  • MAGNETIC TAPE AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20190103130
    Abstract: Provided are a magnetic tape, in which a magnetic layer includes a ferromagnetic powder, a binding agent, and an oxide abrasive, ?SFD in a longitudinal direction of the magnetic tape calculated by Expression 1, ?SFD=SFD25° C.?SFD?190° C., is equal to or smaller than 0.50, 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, 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 tape.
    Type: Application
    Filed: September 27, 2018
    Publication date: April 4, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki OZAWA
  • MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING AND REPRODUCING DEVICE
    Publication number: 20190103134
    Abstract: Provided are a magnetic recording medium, in which a magnetic layer includes 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 coefficient of friction measured regarding a base portion of a surface of the magnetic layer is equal to or smaller than 0.30, 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: Application
    Filed: September 26, 2018
    Publication date: April 4, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki OZAWA
  • MAGNETIC TAPE DEVICE AND HEAD TRACKING SERVO METHOD
    Publication number: 20190096437
    Abstract: The magnetic tape device includes a TMR head (servo head); and a magnetic tape, in which a magnetic layer of the magnetic tape includes fatty acid ester, Ra measured regarding a surface of the magnetic layer is equal to or smaller than 2.0 nm, full widths at half maximum of spacing distribution measured by optical interferometry regarding a surface of the magnetic layer before and after performing a vacuum heating with respect to the magnetic tape are greater than 0 nm and equal to or smaller than 7.0 nm, a difference between spacings before and after the vacuum heating is greater than 0 nm and equal to or smaller than 8.0 nm, and ?SFD (=SFD25° C.?SFD?#° C.) in a longitudinal direction of the magnetic tape is equal to or smaller than 0.50.
    Type: Application
    Filed: November 8, 2018
    Publication date: March 28, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Eiki OZAWA, Norihito KASADA
  • MAGNETIC TAPE DEVICE AND HEAD TRACKING SERVO METHOD
    Publication number: 20190088278
    Abstract: The magnetic tape device includes a magnetic tape including a magnetic layer, in which an intensity ratio of a peak intensity of a diffraction peak of a (110) plane with respect to a peak intensity of a diffraction peak of a (114) plane of a hexagonal ferrite crystal structure 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 direction squareness ratio of the magnetic tape is 0.65 to 1.00, Ra measured regarding a surface of the magnetic layer is equal to or smaller than 2.0 nm, and 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 the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is 45 to 65 atom %.
    Type: Application
    Filed: November 6, 2018
    Publication date: March 21, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki OZAWA
  • Evaluation method of magnetic tape and manufacturing method of magnetic tape
    Patent number: 10236025
    Abstract: Provided are an evaluation method of a magnetic tape, in which the magnetic tape which is an evaluation target includes a magnetic layer including a servo pattern, the method including: reading the servo pattern by a magnetic head including a tunnel magnetoresistance effect type element as a servo pattern reading element; measuring electric resistance of the tunnel magnetoresistance effect type element after the reading; and determining quality of the magnetic tape by using a degree of a decrease in the measured electric resistance from a reference value as an index, and a manufacturing method of a magnetic tape including: evaluating the magnetic tape including a servo pattern in a magnetic layer by the evaluation method.
    Type: Grant
    Filed: December 26, 2017
    Date of Patent: March 19, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Tetsuya Kaneko, Norihito Kasada, Eiki Ozawa
  • MAGNETIC TAPE DEVICE, MAGNETIC REPRODUCING METHOD, AND HEAD TRACKING SERVO METHOD
    Publication number: 20190051325
    Abstract: Provided is a magnetic tape device in which a magnetic tape transportation speed is equal to or lower than 18 m/sec, Ra measured regarding a surface of a magnetic layer of a magnetic tape is equal to or smaller than 2.0 nm, 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 the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is 45 to 65 atom %, and ?SFD (=SFD25°C.?SFD?190° C.) in a longitudinal direction of the magnetic tape is equal to or smaller than 0.50, with the SFD25° C. being SFD measured in a longitudinal direction of the magnetic tape at a temperature of 25° C., and the SFD?190° C. being SFD measured at a temperature of ?190° C.
    Type: Application
    Filed: October 15, 2018
    Publication date: February 14, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Eiki OZAWA
  • MAGNETIC TAPE
    Publication number: 20190027175
    Abstract: The magnetic tape includes a magnetic layer including ferromagnetic powder, non-magnetic powder, and a binding agent and a back coating layer including non-magnetic powder and a binding agent, in which the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, a center line average surface roughness measured regarding a surface of the magnetic layer is equal to or smaller than 1.8 nm, an intensity ratio of a peak intensity of a diffraction peak of a (110) plane with respect to a peak intensity of a diffraction peak of a (114) plane of a hexagonal ferrite crystal structure 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 tape is 0.65 to 1.00, and a contact angle with respect to 1-bromonaphthalene measured regarding a surface of the back coating layer is 15.0° to 30.0°.
    Type: Application
    Filed: July 18, 2018
    Publication date: January 24, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Takuto KUROKAWA, Norihito KASADA, Toshio TADA, Eiki OZAWA
  • MAGNETIC TAPE
    Publication number: 20190027174
    Abstract: Provided is a magnetic tape in which an Ra measured regarding a surface of a magnetic layer is equal to or smaller than 1.8 nm, Int(110)/Int(114) of a hexagonal ferrite crystal structure 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 tape is 0.65 to 1.00, the back coating layer includes one or more kinds of component selected from the group consisting of fatty acid and fatty acid amide, and 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 the surface of the back coating layer at a photoelectron take-off angle of 10 degrees is equal to or greater than 35 atom %.
    Type: Application
    Filed: July 17, 2018
    Publication date: January 24, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Toshio TADA, Norihito KASADA, Eiki OZAWA, Takuto KUROKAWA
  • MAGNETIC RECORDING MEDIUM
    Publication number: 20190027176
    Abstract: The magnetic recording medium includes a non-magnetic support and a magnetic layer containing ferromagnetic powder and a binder, in which the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, the magnetic layer contains an abrasive, an intensity ratio of a peak intensity of a diffraction peak of (110) plane of a crystal structure of the hexagonal ferrite, determined by performing X-ray diffraction analysis on the magnetic layer by using an In-Plane method, to a peak intensity of a diffraction peak of (114) plane of the crystal structure is equal to or higher than 0.5 and equal to or lower than 4.0, a squareness ratio of the magnetic recording medium in a vertical direction is equal to or higher than 0.65 and equal to or lower than 1.00, and a contact angle with 1-bromonaphthalene measured within a surface of the magnetic layer is in a range of 50.0° to 55.0°.
    Type: Application
    Filed: July 17, 2018
    Publication date: January 24, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Takuto KUROKAWA, Norihito KASADA, Toshio TADA, Eiki OZAWA
  • MAGNETIC TAPE AND MAGNETIC TAPE DEVICE
    Publication number: 20190027171
    Abstract: The magnetic tape includes: a non-magnetic support; a non-magnetic layer including non-magnetic powder and a binding agent on the non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic layer, in which a total thickness of the non-magnetic layer and the magnetic layer is equal to or smaller than 0.60 ?m, the magnetic layer has a servo pattern, the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, an intensity ratio of a peak intensity of a diffraction peak of a (110) plane with respect to a peak intensity of a diffraction peak of a (114) plane of a hexagonal ferrite crystal structure obtained by an X-ray diffraction analysis of the magnetic layer by using an In-Plane method is 0.5 to 4.0, and a vertical direction squareness ratio of the magnetic tape is 0.65 to 1.00, and a magnetic tape device including this magnetic tape.
    Type: Application
    Filed: July 18, 2018
    Publication date: January 24, 2019
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • MAGNETIC RECORDING MEDIUM
    Publication number: 20190027168
    Abstract: The magnetic recording medium includes a non-magnetic support and a magnetic layer which contains ferromagnetic powder and a binder, in which the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, the magnetic layer contains an abrasive, Int (110)/Int (114) of a crystal structure of the hexagonal ferrite, determined by performing X-ray diffraction analysis on the magnetic layer by using an In-Plane method, to a peak intensity of a diffraction peak of (114) plane of the crystal structure is equal to or higher than 0.5 and equal to or lower than 4.0, a squareness ratio of the magnetic recording medium in a vertical direction is equal to or higher than 0.65 and equal to or lower than 1.00, and a logarithmic decrement obtained by performing a pendulum viscoelasticity test on a surface of the magnetic layer is equal to or lower than 0.050.
    Type: Application
    Filed: July 18, 2018
    Publication date: January 24, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Toshio TADA, Eiki OZAWA, Takuto KUROKAWA
  • MAGNETIC TAPE AND MAGNETIC TAPE DEVICE
    Publication number: 20190027177
    Abstract: The magnetic tape includes a magnetic layer including ferromagnetic powder and a binding agent, in which a magnetic tape total thickness is equal to or smaller than 5.30 ?m, the magnetic layer has a servo pattern, a center line average surface roughness Ra measured regarding a surface of the magnetic layer is equal to or smaller than 1.8 nm, the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, an intensity ratio of a peak intensity of a diffraction peak of a (110) plane with respect to a peak intensity of a diffraction peak of a (114) plane of a hexagonal ferrite crystal structure obtained by an X-ray diffraction analysis of the magnetic layer by using an In-Plane method is 0.5 to 4.0, and a vertical direction squareness ratio of the magnetic tape is 0.65 to 1.00, and a magnetic tape device including this magnetic tape.
    Type: Application
    Filed: July 18, 2018
    Publication date: January 24, 2019
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • MAGNETIC RECORDING MEDIUM
    Publication number: 20190027178
    Abstract: The magnetic recording medium includes a magnetic layer containing ferromagnetic powder and a binder, in which the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, the magnetic layer contains an abrasive, an intensity ratio of a peak intensity of a diffraction peak of (110) plane of a crystal structure of the hexagonal ferrite, determined by performing X-ray diffraction analysis on the magnetic layer by using an In-Plane method, to a peak intensity of a diffraction peak of (114) plane of the crystal structure is equal to or higher than 0.5 and equal to or lower than 4.0, a squareness ratio of the magnetic recording medium in a vertical direction is equal to or higher than 0.65 and equal to or lower than 1.00, and a coefficient of friction measured in a base material portion within a surface of the magnetic layer is equal to or lower than 0.30.
    Type: Application
    Filed: July 17, 2018
    Publication date: January 24, 2019
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA