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).

  • Patent number: 10515661
    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: Grant
    Filed: November 6, 2018
    Date of Patent: December 24, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Patent number: 10515660
    Abstract: A magnetic tape is provided in which the center line average surface roughness Ra measured regarding the surface of the magnetic layer is less than or equal to 1.8 nm, and the logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is less than or equal to 0.050. A back coating layer includes one or more components selected from a fatty acid and a fatty acid amide. In addition, 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 regarding the surface of the back coating layer at a photoelectron take-off angle of 10 degrees is greater than or equal to 35 atom %.
    Type: Grant
    Filed: June 9, 2017
    Date of Patent: December 24, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Masahito Oyanagi, Norihito Kasada
  • Patent number: 10515657
    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: Grant
    Filed: September 27, 2018
    Date of Patent: December 24, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Patent number: 10510369
    Abstract: A magnetic tape includes a non-magnetic support; a non-magnetic layer including non-magnetic powder and a binder on the non-magnetic support; and a magnetic layer including ferromagnetic powder and a binder on the non-magnetic layer. The total thickness of the non-magnetic layer and the magnetic layer is less than or equal to 0.60 ?m. The magnetic layer includes a timing-based servo pattern, the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, and the magnetic layer includes an abrasive. In addition, the tilt cos ? of the ferromagnetic hexagonal ferrite powder with respect to the surface of the magnetic layer acquired by cross section observation performed using a scanning transmission electron microscope is 0.85 to 1.00.
    Type: Grant
    Filed: June 19, 2017
    Date of Patent: December 17, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Tetsuya Kaneko, Norihito Kasada, Eiki Ozawa
  • Patent number: 10510368
    Abstract: A magnetic tape is provided in which the total thickness is less than or equal to 5.30 ?m. The magnetic layer includes a timing-based servo pattern and also a fatty acid ester; and the magnetic layer surface Ra is less than or equal to 1.8 nm. The full width at half maximum of spacing distribution measured by optical interferometry regarding the surface of the magnetic layer before performing vacuum heating with respect to the magnetic tape is greater than 0 nm and less than or equal to 7.0 nm, while the same value measured after performing the vacuum heating is greater than 0 nm and less than or equal to 7.0 nm, also. The difference between a spacing measured after performing the vacuum heating and a spacing measured before performing the vacuum heating is greater than 0 nm and less than or equal to 8.0 nm.
    Type: Grant
    Filed: June 16, 2017
    Date of Patent: December 17, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Tetsuya Kaneko, Norihito Kasada
  • Patent number: 10510370
    Abstract: A magnetic tape is provided in which the total thickness of a non-magnetic layer and a magnetic layer is equal to or smaller than 0.60 ?m. The magnetic layer includes a timing-based servo pattern and also includes fatty acid ester. The full width at half maximum of spacing distribution measured by optical interferometry regarding the surface of the magnetic layer before performing vacuum heating with respect to the magnetic tape is greater than 0 nm and less than or equal to 7.0 nm, while the same value measured after performing the vacuum heating is also greater than 0 nm and less than or equal to 7.0 nm. Further, the difference between a spacing measured after performing the vacuum heating and a spacing measured before performing the vacuum heating is greater than 0 nm and equal to or smaller than 8.0 nm.
    Type: Grant
    Filed: June 19, 2017
    Date of Patent: December 17, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Tetsuya Kaneko, Norihito Kasada
  • Patent number: 10510366
    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: Grant
    Filed: December 26, 2018
    Date of Patent: December 17, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Tetsuya Kaneko, Norihito Kasada, Eiki Ozawa
  • Patent number: 10504546
    Abstract: A magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binder on the non-magnetic support. The total thickness of the magnetic tape is less than or equal to 5.30 ?m. The magnetic layer includes a timing-based servo pattern. The center line average surface roughness Ra measured regarding the surface of the magnetic layer is less than or equal to 1.8 nm. The ferromagnetic powder is ferromagnetic hexagonal ferrite powder, and the magnetic layer includes an abrasive. Further, the tilt cos ? of the ferromagnetic hexagonal ferrite powder with respect to the surface of the magnetic layer acquired by cross section observation performed using a scanning transmission electron microscope is 0.85 to 1.00.
    Type: Grant
    Filed: June 21, 2017
    Date of Patent: December 10, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Tetsuya Kaneko, Norihito Kasada, Eiki Ozawa
  • Patent number: 10497384
    Abstract: A magnetic tape device includes a magnetic tape; and a Tunneling Magnetoresistive (PAR) head as a reproducing head, in which the center line average surface roughness Ra measured regarding a surface of the magnetic layer of the magnetic tape is equal to or smaller than 2.0 nm, the logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is equal to or smaller than 0.050, and ?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, wherein, in Expression 1, the SFD25° C. is a switching field distribution SFD measured in a longitudinal direction of the magnetic tape at a temperature of 25° C., and the SFD?190° C. is a switching field distribution SFD measured in a longitudinal direction of the magnetic tape at a temperature of ?190° C.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: December 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Patent number: 10497388
    Abstract: A magnetic tape is provided having a total thickness of the non-magnetic and magnetic layers of less than or equal to 0.60 ?m. The C—H derived C concentration calculated from the C—H peak area ratio of C1s spectra by ESCA on the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is greater than or equal to 45 atom %. The full widths at half maximum of spacing distribution measured by optical interferometry regarding the surface of the magnetic layer before and after vacuum heating with respect to the magnetic tape are respectively greater than 0 nm and less than or equal to 7.0 nm, and the difference between a spacing measured after the vacuum heating and a spacing measured before the vacuum heating is greater than 0 nm and less than or equal to 8.0 nm.
    Type: Grant
    Filed: June 16, 2017
    Date of Patent: December 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada, Takuto Kurokawa
  • Patent number: 10497386
    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: Grant
    Filed: November 8, 2018
    Date of Patent: December 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada
  • Patent number: 10497389
    Abstract: The magnetic tape includes a magnetic layer having ferromagnetic powder and a binder on a non-magnetic support, in which the magnetic layer includes a timing-based servo pattern, the ferromagnetic powder is ferromagnetic hexagonal ferrite powder having an activation volume equal to or smaller than 1,600 nm3, and an edge shape of the timing-based servo pattern specified by a magnetic force microscope observation is a shape in which a difference (l99.9?l0.1) between a value l99.9 of a cumulative frequency function of 99.9% of a position deviation width from an ideal shape in a longitudinal direction of the magnetic tape and a value l0.1 of the cumulative frequency function of 0.1% thereof is equal to or smaller than 180 nm.
    Type: Grant
    Filed: August 10, 2018
    Date of Patent: December 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Tetsuya Kaneko, Norihito Kasada, Eiki Ozawa
  • Patent number: 10490220
    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: Grant
    Filed: October 15, 2018
    Date of Patent: November 26, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Patent number: 10482915
    Abstract: The magnetic tape device includes: a magnetic tape; and a reproducing head, in which the reproducing head is a TMR head, the magnetic tape includes a non-magnetic support, and a magnetic layer including ferromagnetic powder, a binding agent, and fatty acid ester on the non-magnetic support, a full width at half maximum of spacing distribution measured by optical interferometry regarding a surface of the magnetic layer before performing a vacuum heating with respect to the magnetic tape is greater than 0 nm and equal to or smaller than 7.0 nm, a full width at half maximum of spacing distribution measured after performing the vacuum heating is greater than 0 nm and equal to or smaller than 7.0 nm, and a difference between a spacing measured by optical interferometry regarding the surface of the magnetic layer after performing the vacuum heating with respect to the magnetic tape and a spacing measured before performing the vacuum heating is greater than 0 nm and equal to or smaller than 9.0 nm.
    Type: Grant
    Filed: December 26, 2017
    Date of Patent: November 19, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Tetsuya Kaneko, Norihito Kasada
  • Patent number: 10482913
    Abstract: A 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. The total thickness of the non-magnetic layer and the magnetic layer is less than or equal to 0.60 ?m. The magnetic layer includes an abrasive, and the percentage of a plan view maximum area of the abrasive confirmed in a region having a size of 4.3 ?m×6.3 ?m of the surface of the magnetic layer with respect to the total area of the region, obtained by plane observation performed by using a scanning electron microscope, is greater than or equal to 0.02% and less than 0.06%. Also, the logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is less than or equal to 0.050.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: November 19, 2019
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Patent number: 10475480
    Abstract: A magnetic tape includes a non-magnetic support; a magnetic layer including ferromagnetic powder and a binding agent on one surface side of the non-magnetic support; and a back coating layer including non-magnetic powder and a binding agent on the other surface side of the non-magnetic support. The center line average surface roughness Ra measured regarding a surface of the magnetic layer is less than or equal to 1.8 nm. The contact angle with respect to 1-bromonaphthalene measured regarding the surface of the magnetic layer is 45.0° to 55.0°. Also, the logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the back coating layer is less than or equal to 0.060.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: November 12, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Takuto Kurokawa, Norihito Kasada
  • Patent number: 10475481
    Abstract: The magnetic tape has a magnetic layer and a backcoat layer. The Ra on the magnetic layer side surface is less than or equal to 1.8 nm, the coefficient of friction measured on the base portion of the magnetic layer side surface is less than or equal to 0.35, and the Ra measured on the backcoat layer side surface is less than or equal to 5.0 nm. The backcoat layer contains a fatty acid ester. In addition, the FWHMbefore measured on the backcoat layer side surface before vacuum heating is greater than 0 nm but less than or equal to 10.0 nm, the FWHMafter after vacuum heating is greater than 0 nm but less than or equal to 10.0 nm, and the difference between the spacing measured on the backcoat layer side surface after and before vacuum heating is greater than 0 nm but less than or equal to 8.0 nm.
    Type: Grant
    Filed: February 2, 2017
    Date of Patent: November 12, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Masahito Oyanagi, Norihito Kasada, Eiki Ozawa
  • Patent number: 10477072
    Abstract: A magnetic tape is provided in which ferromagnetic powder included in a magnetic layer is ferromagnetic hexagonal ferrite powder having an activation volume less than or equal to 1,600 nm3. The magnetic layer includes one or more components selected from a fatty acid and a fatty acid amide, and an abrasive. 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 greater than or equal to 45 atom %. Also, the tilt cos ? of the ferromagnetic hexagonal ferrite powder with respect to the surface of the magnetic layer acquired by cross section observation performed by using a scanning transmission electron microscope is 0.85 to 1.00.
    Type: Grant
    Filed: June 13, 2017
    Date of Patent: November 12, 2019
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Patent number: 10460756
    Abstract: A magnetic tape device includes: a magnetic tape including a servo pattern on a magnetic layer; and a Tunneling Magnetoresistive (TMR) head as a servo head, in which the center line average surface roughness Ra measured regarding a surface of the magnetic layer of the magnetic tape is equal to or smaller than 2.0 nm, the logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is equal to or smaller than 0.050, and ?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, wherein the SFD25° C. is SFD measured in a longitudinal direction of the magnetic tape at a temperature of 25° C., and the SFD?190° C. is SFD measured in a longitudinal direction of the magnetic tape at a temperature of ?190° C.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: October 29, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Patent number: 10453488
    Abstract: A magnetic tape includes a non-magnetic support; and a magnetic layer including ferromagnetic powder and a binding agent on the non-magnetic support. The center line average surface roughness Ra measured regarding the surface of the magnetic layer is less than or equal to 1.8 nm. The logarithmic decrement acquired by a pendulum viscoelasticity test performed regarding the surface of the magnetic layer is less than or equal to 0.050, and the contact angle with respect to 1-bromonaphthalene measured regarding the surface of the magnetic layer is 45.0° to 55.0°.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: October 22, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Takuto Kurokawa, Norihito Kasada