公开(公告)号：US20240170014A1

公开(公告)日：2024-05-23

申请号：US18524922

申请日：2023-11-30

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B5/733 ,  G11B5/708 ,  G11B5/735 ,  G11B5/78

CPC classification number: G11B5/7334 ,  G11B5/708 ,  G11B5/7356 ,  G11B5/78

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 μm 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.

公开(公告)号：US20240105228A1

公开(公告)日：2024-03-28

申请号：US18524724

申请日：2023-11-30

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B5/702 ,  G11B5/708 ,  G11B5/71 ,  G11B5/735 ,  G11B5/78

CPC classification number: G11B5/7028 ,  G11B5/708 ,  G11B5/71 ,  G11B5/7356 ,  G11B5/78

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.

公开(公告)号：US20240105224A1

公开(公告)日：2024-03-28

申请号：US18517870

申请日：2023-11-22

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B5/592 ,  G11B5/706 ,  G11B5/735

CPC classification number: G11B5/5928 ,  G11B5/70615 ,  G11B5/70678 ,  G11B5/7356

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 μm to 50 μm, 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 μm 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.

公开(公告)号：US20240096364A1

公开(公告)日：2024-03-21

申请号：US18467474

申请日：2023-09-14

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B5/706 ,  G11B5/008 ,  G11B5/588

CPC classification number: G11B5/70615 ,  G11B5/00817 ,  G11B5/588

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 σ of the friction coefficient in a width direction of the surface of the magnetic layer is 0.05 nm or less.

公开(公告)号：US20230335160A1

公开(公告)日：2023-10-19

申请号：US18299289

申请日：2023-04-12

Applicant: FUJIFILM Corporation

Inventor： Yuto MURATA ,  Norihito KASADA ,  Nagisa YAMASAKI

IPC: G11B5/735 ,  G11B5/78 ,  G11B20/20

CPC classification number: G11B5/7356 ,  G11B5/78 ,  G11B20/20

Abstract: The magnetic tape includes: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, in which a non-linear component of tape width deformation generated by storage for 10 days in an environment of a temperature of 60° C. and a relative humidity of 20% is 100 nm or less. A magnetic tape cartridge and a magnetic tape apparatus include the magnetic tape.

公开(公告)号：US20230065359A1

公开(公告)日：2023-03-02

申请号：US17822803

申请日：2022-08-29

Applicant: FUJIFILM CORPORATION

Inventor： Junichi NAKAMIGAWA ,  Yasushi KOMORI ,  Yusuke KANEKO ,  Tadashi KIRA ,  Norihito KASADA ,  Toru NAKAO

IPC: G11B5/584 ,  G11B5/008

Abstract: A magnetic tape cartridge includes a case that accommodates a magnetic tape on which a plurality of servo bands and a plurality of data bands are formed, servo patterns being recorded in the servo bands, and a memory provided in the case. The memory stores servo pattern interval-related information related to a servo pattern interval determined for each of the plurality of data bands included in the magnetic tape. The servo pattern interval is commonly used for a plurality of division areas obtained by dividing the data band in a width direction of the magnetic tape, and is a representative interval between a first servo pattern and a second servo pattern.

公开(公告)号：US20230038397A1

公开(公告)日：2023-02-09

申请号：US17872651

申请日：2022-07-25

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B5/73 ,  G11B5/127 ,  G11B5/78

Abstract: A magnetic tape device. The angle θ 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 a maximum value of an absolute value of a difference between a servo band spacing obtained before storage in a predetermined environment and a servo band spacing obtained after storage in the environment for a storage time T is defined as A, and T is set to a plurality of predetermined times, 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 T obtained for each T is 5 years or longer.

公开(公告)号：US20220358958A1

公开(公告)日：2022-11-10

申请号：US17730311

申请日：2022-04-27

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA ,  Yusuke Kaneko

IPC: G11B5/17 ,  G11B5/78

Abstract: In the magnetic tape, in a case where a maximum value of an absolute value of a difference between a servo band spacing obtained before storage, and a servo band spacing obtained after storage of N cycles, in a case where predetermined storage is set to one cycle, is defined as A, a medium life calculated by a linear function that is derived from the value of A and the value of the logarithm logeT of total storage time T of the storage of N cycles is 3 years or longer. The medium life is T in a case where the A satisfies Equation a: A=1.5−B. The B is calculated by multiplying a difference between a maximum value and a minimum value of the servo band spacings obtained in each of the five environments by ½.

公开(公告)号：US20220254375A1

公开(公告)日：2022-08-11

申请号：US17591593

申请日：2022-02-02

Applicant: FUJIFILM CORPORATION

Inventor： Yusuke KANEKO ,  Toru NAKAO ,  Atsushi MUSHA ,  Norihito KASADA

IPC: G11B5/78

Abstract: A magnetic tape cartridge includes a case in which a magnetic tape is housed, and an NVM of a cartridge memory provided in the case. The NVM stores cartridge information including an identification ID regarding an allowable range of temperature/humidity in using the magnetic tape, an upper limit of a preservation period of the magnetic tape, and an upper limit of a use frequency of the magnetic tape.

公开(公告)号：US20220199116A1

公开(公告)日：2022-06-23

申请号：US17645697

申请日：2021-12-22

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B15/093 ,  G11B5/008 ,  G11B5/78

Abstract: The magnetic tape cartridge includes a magnetic tape, and a cartridge reel, in which, in the magnetic tape, a minimum winding deviation occurrence load measured after the magnetic tape is rewound around the cartridge reel by applying a tension of 0.30 N in a longitudinal direction of the magnetic tape is 250 N or less.