公开(公告)号：US20250014604A1

公开(公告)日：2025-01-09

申请号：US18758395

申请日：2024-06-28

Applicant: FUJIFILM Corporation

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

IPC: G11B5/78 ,  G11B5/55 ,  G11B5/592 ,  G11B5/706 ,  G11B5/714 ,  G11B5/735

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. Sci obtained by measuring a surface of the magnetic layer with an atomic force microscope and by Equation A is 1.40 or more and 1.60 or less, and standard deviation σ of the Sci in a width direction of the surface of the magnetic layer is 0.05 or less. In Equation A, Sq is a root-mean-square height Sq specified in ISO 25178, Vv(h0.05)-Vv(h0.8) is a void volume in a region where a load area ratio in a bearing curve is 5% or more and 80% or less, and A is a measurement region area. Sci = ( Vv ⁢ ( h 0.05 ) - Vv ⁢ ( h 0.8 ) A ) / Sq Equation ⁢ A

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：US20250014598A1

公开(公告)日：2025-01-09

申请号：US18759114

申请日：2024-06-28

Applicant: FUJIFILM Corporation

Inventor： Ryosuke YUMIYAMA ,  Norihito Kasada ,  Nobuhito Onozuka ,  Junya Sawada

IPC: G11B5/706 ,  G11B5/55 ,  G11B5/714 ,  G11B5/735 ,  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. A protruding peak height Spk specified in ISO 25178 on a surface of the magnetic layer is 1.5 nm or more and 3.0 nm or less, and standard deviation σ of the Spk in a width direction of the surface of the magnetic layer is 0.5 nm or less.

公开(公告)号：US20250006225A1

公开(公告)日：2025-01-02

申请号：US18759153

申请日：2024-06-28

Applicant: FUJIFILM Corporation

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

IPC: G11B5/706 ,  G11B5/592 ,  G11B5/714 ,  G11B5/735 ,  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. A dale void volume Vvv specified in ISO 25178 on a surface of the magnetic layer is 0.100 nm3 or more and 0.350 nm3 or less, and standard deviation a of the Vvv in a width direction of the surface of the magnetic layer is 0.020 nm3 or less.