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 AND MAGNETIC TAPE DEVICE
    Publication number: 20190295590
    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: Application
    Filed: June 13, 2019
    Publication date: September 26, 2019
    Applicant: FUJIFILM Corporation
    Inventors: Tetsuya Kaneko, Norihito Kasada, Eiki Ozawa
  • Magnetic tape having characterized back coating layer
    Patent number: 10424330
    Abstract: A magnetic tape includes a back coating layer having a thickness less than or equal to 0.30 ?m and containing fatty acid ester. 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. The full width at half maximum of spacing distribution measured by optical interferometry regarding the surface of the back coating layer before and after performing a vacuum heating with respect to the magnetic tape is respectively greater than 0 nm and less than or equal to 10.0 nm, and the difference between the spacing measured by optical interferometry regarding the surface of the back coating layer after performing the vacuum heating and the spacing measured before performing the vacuum heating is greater than 0 nm and less than or equal to 8.0 nm.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: September 24, 2019
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Magnetic tape device and magnetic reproducing method
    Patent number: 10410665
    Abstract: The magnetic tape device includes a TMR head (reproducing head); and a magnetic tape including a magnetic layer including ferromagnetic hexagonal ferrite powder, a binding agent, and fatty acid ester, in which an XRD intensity ratio 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 is 0.65 to 1.00, 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 the 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, and a difference between spacings before and after the vacuum heating is greater than 0 nm and equal to or smaller than 8.0 nm.
    Type: Grant
    Filed: March 14, 2018
    Date of Patent: September 10, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada
  • Magnetic tape device and magnetic reproducing method
    Patent number: 10410666
    Abstract: The magnetic tape device includes a magnetic tape including a magnetic layer; and a TMR head (reproducing head), 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: March 14, 2018
    Date of Patent: September 10, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Magnetic tape having characterized back coating layer
    Patent number: 10403318
    Abstract: A magnetic tape in which a thickness of a back coating layer is equal to or smaller than 0.20 ?m. 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 %. The full widths at half maximum of spacing distribution measured by optical interferometry regarding the surface of the back coating layer before and after performing a vacuum heating with respect to the magnetic tape are respectively greater than 0 nm and equal to or smaller than 10.0 nm. The difference between the 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 16, 2017
    Date of Patent: September 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Takuto Kurokawa, Eiki Ozawa, Norihito Kasada
  • Magnetic tape device with TMR head and specific logarithmic decrement and magnetic reproducing method
    Patent number: 10403320
    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: September 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa, Tetsuya Kaneko
  • Magnetic tape having characterized magnetic layer, tape cartridge, and recording and reproducing device
    Patent number: 10403319
    Abstract: The magnetic tape includes a nonmagnetic layer containing nonmagnetic powder and binder on a nonmagnetic support, and a magnetic layer containing ferromagnetic powder, abrasive, and binder on the nonmagnetic layer, wherein a thickness of the nonmagnetic layer is less than or equal to 0.50 ?m, a coefficient of friction as measured on a base portion of a surface of the magnetic layer is less than or equal to 0.35, and ?SFD in a longitudinal direction of the magnetic tape as calculated with Equation 1, ?SFD=SFD25° C.?SFD?190° C., is greater than or equal to 0.50, wherein, in Equation 1, SFD25° C. denotes a SFD as measured in the longitudinal direction of the magnetic tape in an environment with a temperature of 25° C., and SFD?190° C. denotes a SFD as measured in the longitudinal direction of the magnetic tape in an environment with a temperature of ?190° C.
    Type: Grant
    Filed: December 15, 2016
    Date of Patent: September 3, 2019
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Magnetic tape device and magnetic reproducing method
    Patent number: 10403312
    Abstract: The magnetic tape device includes a TMR head and a magnetic tape, in which the magnetic tape includes fatty acid ester in a magnetic layer, Ra measured regarding a surface of the magnetic layer is 2.0 nm or smaller, 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 7.0 nm or smaller, a difference between spacings before and after the vacuum heating is greater than 0 nm and 8.0 nm or smaller, and a ratio of an average area Sdc of a magnetic cluster of the magnetic tape in a DC demagnetization state and an average area Sac of a magnetic cluster thereof in an AC demagnetization state measured with a magnetic force microscope is 0.80 to 1.30.
    Type: Grant
    Filed: March 14, 2018
    Date of Patent: September 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada
  • Magnetic tape device employing TMR head and magnetic tape with characterized magnetic layer, and head tracking servo method
    Patent number: 10403314
    Abstract: A magnetic tape device includes a TMR head as a servo head; and a magnetic tape which includes a magnetic layer including ferromagnetic hexagonal ferrite powder and a binding agent, and including a servo pattern. The XRD intensity ratio (Int(110)/Int(114)) of the hexagonal ferrite crystal structure obtained by an X-ray diffraction analysis of the magnetic layer using an In-Plane method is 0.5 to 4.0. The vertical direction squareness ratio of the magnetic tape is 0.65 to 1.00. The center line average surface roughness Ra measured regarding the surface of the magnetic layer is less than or equal to 2.0 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.
    Type: Grant
    Filed: February 20, 2018
    Date of Patent: September 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Magnetic tape device and magnetic reproducing method
    Patent number: 10403317
    Abstract: The magnetic tape device includes a magnetic tape and a TMR head, in which 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 ferromagnetic powder is ferromagnetic hexagonal ferrite powder, an intensity ratio of a peak intensity Int(110) of a diffraction peak of a (110) plane with respect to a peak intensity Int(114) 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.
    Type: Grant
    Filed: March 14, 2018
    Date of Patent: September 3, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Magnetic tape having characterized magnetic layer with servo pattern and magnetic tape device
    Patent number: 10403316
    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: Grant
    Filed: July 18, 2018
    Date of Patent: September 3, 2019
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Magnetic tape device and head tracking servo method
    Patent number: 10395685
    Abstract: The magnetic tape device includes a TMR head (servo head); and a magnetic tape including a magnetic layer including ferromagnetic hexagonal ferrite powder, a binding agent, and fatty acid ester, in which an XRD intensity ratio 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 is 0.65 to 1.00, 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, and a difference between spacings before and after the vacuum heating is greater than 0 nm and equal to or smaller than 8.0 nm.
    Type: Grant
    Filed: March 14, 2018
    Date of Patent: August 27, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada
  • MAGNETIC TAPE CARTRIDGE
    Publication number: 20190259417
    Abstract: Provided is a magnetic tape cartridge of a single reel type in which a magnetic tape is wound around a reel, in which the magnetic tape includes a non-magnetic support, and a magnetic layer including a ferromagnetic powder and a binding agent on the non-magnetic support, a tape thickness is equal to or smaller than 5.2 a tape width difference (B?A) between a tape width A at a position of 10 m±1 m from a tape outer end and a tape width B at a position of 50 m±1 m from a tape inner end is 2.4 ?m to 12.0 ?m, and the tape width A and the tape width B are values measured 100 days from the date of magnetic tape cartridge manufacture.
    Type: Application
    Filed: February 21, 2019
    Publication date: August 22, 2019
    Inventors: Yusuke KAGAWA, Norihito Kasada, Yuto Murata
  • Magnetic tape device and head tracking servo method
    Patent number: 10373633
    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, 2017
    Date of Patent: August 6, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Tetsuya Kaneko, Norihito Kasada, Eiki Ozawa
  • Magnetic tape device and head tracking servo method
    Patent number: 10373639
    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: March 14, 2018
    Date of Patent: August 6, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Eiki Ozawa
  • Head positioning of timing-based servo system for magnetic tape recording device
    Patent number: 10366721
    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 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, an XRD 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 direction squareness ratio of the magnetic tape is 0.65 to 1.00, and an edge shape of the timing-based servo pattern specified by magnetic force microscope observation is a shape in which a difference (L99.9?L0.1) is equal to or smaller than 180 nm, and a magnetic tape device including the magnetic tape.
    Type: Grant
    Filed: June 15, 2018
    Date of Patent: July 30, 2019
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Magnetic tape device and head tracking servo method
    Patent number: 10360937
    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?190° C.) in a longitudinal direction of the magnetic tape is equal to or smaller than 0.50.
    Type: Grant
    Filed: March 14, 2018
    Date of Patent: July 23, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Norihito Kasada
  • Magnetic tape having characterized backcoat layer and method of manufacturing the same
    Patent number: 10347279
    Abstract: A magnetic tape has a magnetic layer and a backcoat layer. Each of the magnetic layer and the backcoat layer contains a fatty acid ester. The Ra measured on the magnetic layer side surface is less than or equal to 2.8 nm. The difference between the spacing measured by optical interferometry on the magnetic layer side surface after and before vacuum heating is greater than 0 nm but less than or equal to 8.0 nm. The FWHMbefore on the backcoat layer side surface is greater than 0 nm but less than or equal to 10.0 nm. The FWHMafter on the backcoat layer side surface is greater than 0 nm but less than or equal to 10.0 nm. 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: July 9, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Eiki Ozawa, Masahito Oyanagi, Norihito Kasada
  • Magnetic tape having characterized magnetic layer and magnetic tape device
    Patent number: 10347280
    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: July 9, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Tetsuya Kaneko, Eiki Ozawa
  • Magnetic tape device and head tracking servo method
    Patent number: 10325620
    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, 2017
    Date of Patent: June 18, 2019
    Assignee: FUJIFILM Corporation
    Inventors: Tetsuya Kaneko, Norihito Kasada, Eiki Ozawa