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: 11972784
    Abstract: The magnetic tape cartridge group includes a plurality of magnetic tape cartridges. Regarding 100 reels of magnetic tape cartridges, in a case where a maximum value of an absolute value of a difference between a servo band spacing obtained before predetermined storage and a servo band spacing obtained after the predetermined storage is defined as A, an arithmetic mean of medium lives calculated by a linear function derived from a value of A obtained for different N and a value of the logarithm of total storage time T of the storage of N cycles is 3 years or longer and 3? is 1 year or shorter. Medium life: T in a case where A satisfies A=1.5?B. B: a value calculated by multiplying a difference between a maximum value and a minimum value of servo band spacings obtained in each of the five environments by ½.
    Type: Grant
    Filed: June 23, 2022
    Date of Patent: April 30, 2024
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Yusuke Kaneko
  • Publication number: 20240119963
    Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which the number of recesses existing on a surface of the magnetic layer and having an equivalent circle diameter of 0.25 ?m or more and 0.55 ?m or less is 10 or more and 500 or less per an area of 40 ?m×40 ?m, and standard deviation a of the number of the recesses in a width direction of the surface of the magnetic layer is 50 or less.
    Type: Application
    Filed: September 13, 2023
    Publication date: April 11, 2024
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Publication number: 20240112698
    Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which an arithmetic average roughness Ra measured on a surface of the magnetic layer is 1.5 nm or less, and standard deviation a of the Ra in a width direction of the surface of the magnetic layer is 0.20 nm or less.
    Type: Application
    Filed: September 1, 2023
    Publication date: April 4, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Yujin SHIBATA, Norihito KASADA, Takuto KUROKAWA, So MATSUYAMA
  • Publication number: 20240112697
    Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which an AlFeSil abrasion value measured on a surface of the magnetic layer is 20 ?m or more and 50 ?m or less, and standard deviation a of the AlFeSil abrasion value obtained in a width direction of the surface of the magnetic layer is 5.0 ?m or less.
    Type: Application
    Filed: September 14, 2023
    Publication date: April 4, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Takuto KUROKAWA, Yujin SHIBATA, Norihito KASADA, So MATSUYAMA
  • Publication number: 20240105229
    Abstract: A magnetic tape in which a tape thickness of the magnetic tape is 5.2 ?m or less, and in an environment with a temperature of 23° C. and a relative humidity of 50%, an AlFeSil abrasion value45° of a surface of the magnetic layer measured at a tilt angle of 45° of an AlFeSil prism is 20 ?m to 50 ?m, a standard deviation of an AlFeSil abrasion value of the surface of the magnetic layer measured at each of tilt angles of 0°, 15°, 30°, and 45° of the AlFeSil prism is 30 ?m or less, and the tilt angle of the AlFeSil prism is an angle formed by a longitudinal direction of the AlFeSil prism and a width direction of the magnetic tape.
    Type: Application
    Filed: November 21, 2023
    Publication date: March 28, 2024
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Publication number: 20240105224
    Abstract: A magnetic tape in which an arithmetic average roughness Ra measured at a surface of the magnetic layer with an atomic force microscope is 2.0 nm or less, and in an environment with a temperature of 23° C. and a relative humidity of 50%, an AlFeSil abrasion value45° of a surface of the magnetic layer measured at a tilt angle of 45° of an AlFeSil prism is 20 ?m to 50 ?m, a standard deviation of an AlFeSil abrasion value of the surface of the magnetic layer measured at each of tilt angles of 0°, 15°, 30°, and 45° of the AlFeSil prism is 30 ?m or less, and the tilt angle of the AlFeSil prism is an angle formed by a longitudinal direction of the AlFeSil prism and a width direction of the magnetic tape.
    Type: Application
    Filed: November 22, 2023
    Publication date: March 28, 2024
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Publication number: 20240105227
    Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, and a magnetic tape cartridge and a magnetic tape apparatus include the magnetic tape. 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, the number of bright regions having an equivalent circle diameter of 60 nm or more and less than 120 nm is 8000 or more and 30000 or less. Standard deviation ? of the number of the bright regions in a width direction of the surface of the magnetic layer is 2000 or less.
    Type: Application
    Filed: November 30, 2023
    Publication date: March 28, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Yuto MURATA, Nagisa YAMASAKI
  • Publication number: 20240105223
    Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which a contact angle with 1-bromonaphthalene, which is measured on a surface of the magnetic layer, is 45.0° or more and 55.0° or less, and standard deviation ? of the contact angle in a width direction of the surface of the magnetic layer is 1.0° or less.
    Type: Application
    Filed: September 14, 2023
    Publication date: March 28, 2024
    Applicant: FUJIFILM Corporation
    Inventors: Norihito KASADA, Yujin SHIBATA, Takuto KUROKAWA, So MATSUYAMA
  • Publication number: 20240105228
    Abstract: A magnetic tape in which a C—H derived C concentration calculated from a C—H peak surface area ratio in C1s spectra obtained by X-ray photoelectron spectroscopy performed on a surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is 45 atom % to 65 atom %, and in an environment with a temperature of 32° C. and a relative humidity of 80%, a frictional force F45° on the surface of the magnetic layer with respect to an LTO8 head measured at a head tilt angle of 45° is 4 gf to 15 gf, and a standard deviation of a frictional force F on the surface of the magnetic layer with respect to the LTO8 head measured at each of head tilt angles of 0°, 15°, 30°, and 45° is 10 gf or less.
    Type: Application
    Filed: November 30, 2023
    Publication date: March 28, 2024
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Publication number: 20240096364
    Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which a friction coefficient measured on a base portion of a surface of the magnetic layer is 0.35 or less, and standard deviation ? of the friction coefficient in a width direction of the surface of the magnetic layer is 0.05 nm or less.
    Type: Application
    Filed: September 14, 2023
    Publication date: March 21, 2024
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Publication number: 20240096363
    Abstract: A magnetic tape in which a vertical switching field distribution SFD of the magnetic tape is 1.5 or less, and in an environment with a temperature of 23° C. and a relative humidity of 50%, an AlFeSil abrasion value45° of a surface of the magnetic layer measured at a tilt angle of 45° of an AlFeSil prism is 20 ?m to 50 ?m, a standard deviation of an AlFeSil abrasion value of the surface of the magnetic layer measured at each of tilt angles of 0°, 15°, 30°, and 45° of the AlFeSil prism is 30 ?m or less, and the tilt angle of the AlFeSil prism is an angle formed by a longitudinal direction of the AlFeSil prism and a width direction of the magnetic tape.
    Type: Application
    Filed: November 21, 2023
    Publication date: March 21, 2024
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Publication number: 20240096366
    Abstract: A magnetic tape in which an edge weave amount of a tape edge on at least one side of the magnetic tape is 1.5 um or less, and in an environment with a temperature of 23° C. and a relative humidity of 50%, an AlFeSil abrasion value45° of a surface of the magnetic layer measured at a tilt angle of 45° of an AlFeSil prism is 20 ?m to 50 ?m, a standard deviation of an AlFeSil abrasion value of the surface of the magnetic layer measured at each of tilt angles of 0°, 15°, 30°, and 45° of the AlFeSil prism is 30 ?m or less, and the tilt angle of the AlFeSil prism is an angle formed by a longitudinal direction of the AlFeSil prism and a width direction of the magnetic tape.
    Type: Application
    Filed: November 22, 2023
    Publication date: March 21, 2024
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Publication number: 20240096367
    Abstract: A magnetic tape in which a C—H derived C concentration calculated from a C—H peak surface area ratio in C1s spectra obtained by XPS performed on a surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is 45 atom % to 65 atom %, and in an environment with a temperature of 23° C. and a relative humidity of 50%, an AlFeSil abrasion value45° of the surface of the magnetic layer measured at a tilt angle of 45° of an AlFeSil prism is 20 ?m to 50 ?m, a standard deviation of an AlFeSil abrasion value of the surface of the magnetic layer measured at each of given tilt angles of the AlFeSil prism is 30 ?m or less, and the tilt angle of the AlFeSil prism is an angle formed by a longitudinal direction of the AlFeSil prism and a width direction of the magnetic tape.
    Type: Application
    Filed: October 31, 2023
    Publication date: March 21, 2024
    Applicant: FUJIFILM Corporation
    Inventor: Norihito KASADA
  • Publication number: 20240096365
    Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which a contact angle with water, which is measured on a surface of the magnetic layer, is 95° or more and 105° or less, and standard deviation a of the contact angle in a width direction of the surface of the magnetic layer is 1.0° or less.
    Type: Application
    Filed: September 14, 2023
    Publication date: March 21, 2024
    Applicant: FUJIFILM Corporation
    Inventors: So MATSUYAMA, Takuto KUROKAWA, Norihito KASADA, Yujin SHIBATA
  • Patent number: 11922981
    Abstract: A magnetic tape device. The angle ? formed by the axis of the element array of the magnetic head with respect to a width direction of the magnetic tape is changed during running of the magnetic tape in the magnetic tape device. In a case where predetermined storage is defined as one cycle, a maximum value of an absolute value of a difference between a servo band spacing obtained before performing the storage and a servo band spacing obtained after the storage of N cycles is defined as A, and N is set to 1, 2, 3, 4, or 5, a medium life calculated by a linear function of A and a logarithm loge T of T, that are derived from a value of A and a value of the logarithm loge T of total storage time T of the storage of N cycles is 5 years or longer.
    Type: Grant
    Filed: July 25, 2022
    Date of Patent: March 5, 2024
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Patent number: 11900977
    Abstract: A magnetic tape in which an arithmetic average roughness Ra measured at a surface of a magnetic layer with an atomic force microscope is 2.0 nm or less, and in an environment with a temperature of 32° C. and a relative humidity of 80%, a frictional force F45° on the surface of the magnetic layer with respect to an LTO8 head measured at a head tilt angle of 45° is 4 gf to 15 gf, and a standard deviation of a frictional force F on the surface of the magnetic layer with respect to the LTO8 head measured at each of head tilt angles of 0°, 15°, 30°, and 45° is 10 gf or less.
    Type: Grant
    Filed: September 28, 2022
    Date of Patent: February 13, 2024
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Patent number: 11894034
    Abstract: A magnetic tape in which an edge weave amount of a tape edge on at least one side of the magnetic tape is 1.5 ?m or less, and in an environment with a temperature of 32° C. and a relative humidity of 80%, a frictional force F45° on the surface of the magnetic layer with respect to an LTO8 head measured at a head tilt angle of 45° is 4 gf to 15 gf, and a standard deviation of a frictional force F on the surface of the magnetic layer with respect to the LTO8 head measured at each of head tilt angles of 0°, 15°, 30°, and 45° is 10 gf or less.
    Type: Grant
    Filed: September 28, 2022
    Date of Patent: February 6, 2024
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Patent number: 11894033
    Abstract: A magnetic tape in which a vertical switching field distribution SFD of the magnetic tape is 1.5 or less, and in an environment with a temperature of 32° C. and a relative humidity of 80%, a frictional force F45° on the surface of the magnetic layer with respect to an LTO8 head measured at a head tilt angle of 45° is 4 gf to 15 gf, and a standard deviation of a frictional force F on the surface of the magnetic layer with respect to the LTO8 head measured at each of head tilt angles of 0°, 15°, 30°, and 45° is 10 gf or less.
    Type: Grant
    Filed: September 28, 2022
    Date of Patent: February 6, 2024
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada
  • Patent number: 11887636
    Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, and a magnetic tape cartridge and a magnetic tape apparatus include the magnetic tape. 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, the number of bright regions having an equivalent circle diameter of 60 nm or more and less than 120 nm is 8000 or more and 30000 or less. Standard deviation ? of the number of the bright regions in a width direction of the surface of the magnetic layer is 2000 or less.
    Type: Grant
    Filed: April 11, 2023
    Date of Patent: January 30, 2024
    Assignee: FUJIFILM Corporation
    Inventors: Norihito Kasada, Yuto Murata, Nagisa Yamasaki
  • Patent number: 11887637
    Abstract: A magnetic tape in which a C—H derived C concentration calculated from a C—H peak surface area ratio in C1s spectra obtained by X-ray photoelectron spectroscopy performed on a surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is 45 atom % to 65 atom %, and in an environment with a temperature of 32° C. and a relative humidity of 80%, a frictional force F45° on the surface of the magnetic layer with respect to an LTO8 head measured at a head tilt angle of 45° is 4 gf to 15 gf, and a standard deviation of a frictional force F on the surface of the magnetic layer with respect to the LTO8 head measured at each of head tilt angles of 0°, 15°, 30°, and 45° is 10 gf or less.
    Type: Grant
    Filed: September 28, 2022
    Date of Patent: January 30, 2024
    Assignee: FUJIFILM Corporation
    Inventor: Norihito Kasada