公开(公告)号：US20250014603A1

公开(公告)日：2025-01-09

申请号：US18758784

申请日：2024-06-28

Applicant: FUJIFILM Corporation

Inventor： Ryosuke YUMIYAMA ,  Norihito KASADA ,  Nobuhito ONOZUKA ,  Junya SAWADA

IPC: G11B5/73 ,  G11B5/78

Abstract: The magnetic tape includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder. A magnetic tape cartridge and a magnetic tape apparatus include the magnetic tape. An arithmetic average curvature Spc of a peak point specified in ISO 25178 on a surface of the magnetic layer is 0.30 (1/μm) or more and 0.70 (1/μm) or less, and standard deviation a of the Spc in a width direction of the surface of the magnetic layer is 0.15 (1/μm) or less.

公开(公告)号：US20240177733A1

公开(公告)日：2024-05-30

申请号：US18422850

申请日：2024-01-25

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B5/65 ,  G11B5/008 ,  G11B5/588

CPC classification number: G11B5/653 ,  G11B5/00813 ,  G11B5/588

Abstract: Provided is a magnetic tape, in which, in an environment of a temperature of 32° C. and a relative humidity of 80%, a frictional force F45° on a magnetic layer surface with respect to an LTO8 head measured at a head tilt angle of 45° is 4 gf or more and 15 gf or less, and standard deviation of a frictional force F on the magnetic layer surface with respect to the LTO8 head measured at each of head tilt angles of 0°, 15°, 30°, and 45° is 10 gf or less. A magnetic tape cartridge and a magnetic tape apparatus include the magnetic tape.

公开(公告)号：US20240105223A1

公开(公告)日：2024-03-28

申请号：US18467336

申请日：2023-09-14

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA ,  Yujin SHIBATA ,  Takuto KUROKAWA ,  So MATSUYAMA

IPC: G11B5/584 ,  G11B5/702 ,  G11B5/706 ,  G11B5/714 ,  G11B5/78 ,  G11B15/43

CPC classification number: G11B5/584 ,  G11B5/7021 ,  G11B5/70678 ,  G11B5/714 ,  G11B5/78 ,  G11B15/43

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 σ of the contact angle in a width direction of the surface of the magnetic layer is 1.0° or less.

公开(公告)号：US20240096365A1

公开(公告)日：2024-03-21

申请号：US18467585

申请日：2023-09-14

Applicant: FUJIFILM Corporation

Inventor： So MATSUYAMA ,  Takuto KUROKAWA ,  Norihito KASADA ,  Yujin SHIBATA

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 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.

公开(公告)号：US20240096363A1

公开(公告)日：2024-03-21

申请号：US18516455

申请日：2023-11-21

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B5/65 ,  G11B5/008 ,  G11B5/588

CPC classification number: G11B5/65 ,  G11B5/00813 ,  G11B5/588

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 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：US20230154494A1

公开(公告)日：2023-05-18

申请号：US18158048

申请日：2023-01-23

Applicant: FUJIFILM Corporation

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

IPC: G11B15/43

CPC classification number: G11B15/43

Abstract: Provided is a magnetic tape cartridge including: a case in which a magnetic tape is accommodated; and a storage medium provided in the case, in which the storage medium stores tension allowable range related information regarding an allowable range of tension applied to the magnetic tape.

公开(公告)号：US20230110514A1

公开(公告)日：2023-04-13

申请号：US17953953

申请日：2022-09-27

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B5/55 ,  G11B5/735 ,  G11B5/78 ,  G11B5/65

Abstract: A magnetic tape in which a tape thickness of the magnetic tape is 5.2 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：US20220358961A1

公开(公告)日：2022-11-10

申请号：US17730763

申请日：2022-04-27

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA ,  Yusuke Kaneko

IPC: G11B5/592 ,  G11B5/78 ,  G11B5/706 ,  G11B5/735 ,  G11B23/107

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 in an environment of a temperature of 32° C. and relative humidity of 55% and a servo band spacing obtained after storage in the environment for a storage time T is set to A, and T is defined as 24 hours, 48 hours, 72 hours, 96 hours, or 120 hours, a medium life calculated by a linear function of A and a logarithm logeT of T, that are derived from a value of A and a value of the logarithm logeT of T obtained for each T is 3 years or longer. The medium life is T in a case where the A satisfies Equation 1: A=1.5−B.

公开(公告)号：US20220013146A1

公开(公告)日：2022-01-13

申请号：US17366039

申请日：2021-07-02

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA ,  Yusuke KAGAWA

IPC: G11B23/107 ,  G11B5/592 ,  G11B5/706 ,  G11B5/735 ,  G11B5/714 ,  G11B15/43

Abstract: The magnetic tape cartridge includes a magnetic tape, and a cartridge reel. 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 0.40 N in a longitudinal direction of the magnetic tape is 300 N or less.

公开(公告)号：US20210375318A1

公开(公告)日：2021-12-02

申请号：US17331651

申请日：2021-05-27

Applicant: FUJIFILM Corporation

Inventor： Norihito KASADA

IPC: G11B23/087 ,  G11B15/43 ,  G11B5/706 ,  G11B5/714 ,  G11B5/735 ,  G11B5/592

Abstract: A magnetic tape device, in which a magnetic tape is caused to run between a winding reel and a cartridge reel in a state where a tension is applied in a longitudinal direction of the magnetic tape and a maximum value of the tension is 0.50 N or more, and the magnetic tape after running in a state where the tension is applied is caused to be wound around the cartridge reel by applying a tension of 0.40 N or less in the longitudinal direction of the magnetic tape, and a curvature of the magnetic tape in the longitudinal direction is 4 mm/m or less.