# US 2024/0212709 A1 · Magnetic tape, magnetic tape cartridge, and magnetic tape apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0212709 A1 - Document ID: US20240212709A1 - Status: Published application - Kind: A1 - Application number: 18/538,907 - Filed: 2023-12-13 - Published: 2024-06-27 - Earliest claimed: 2022-12-14 - Assignees: FUJIFILM Corporation - Applicants: FUJIFILM Corporation - Inventors: Norihito KASADA - Web page: https://patentgrep.com/patent/US20240212709A1 ## CPC - G11B 5/658: {containing oxygen, e.g. molecular oxygen or magnetic oxide} - G11B 5/70: on a base layer - G11B 5/70678: {Ferrites} - G11B 5/7356: {comprising non-magnetic particles in the back layer, e.g. particles of TiO2, ZnO or SiO2} - G11B 5/736: {Non-magnetic layer under a soft magnetic layer, e.g. between a substrate and a soft magnetic underlayer [SUL] or a keeper layer (magnetic recording media substrates G11B5/739)} - G11B 5/78: Tape carriers - G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R) ## Abstract The magnetic tape includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder. The ferromagnetic powder is a hexagonal ferrite powder, tilt cos θ of the hexagonal ferrite powder with respect to a surface of the magnetic layer, which is acquired by cross-sectional observation performed using a scanning transmission electron microscope, is 0.85 or more and 1.00 or less, and standard deviation σ of the cos θ in a width direction of the surface of the magnetic layer is 0.03 or less. ## Claims ### Claim 1 A magnetic tape comprising: a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, wherein the ferromagnetic powder is a hexagonal ferrite powder, tilt cos θ of the hexagonal ferrite powder with respect to a surface of the magnetic layer, which is acquired by cross-sectional observation performed using a scanning transmission electron microscope, is 0.85 or more and 1.00 or less, and standard deviation σ of the cos θ in a width direction of the surface of the magnetic layer is 0.03 or less. ### Claim 2 (depends on 1) The magnetic tape according to claim 1, wherein the standard deviation σ of the cos θ is more than 0.00 and 0.03 or less. ### Claim 3 (depends on 1) The magnetic tape according to claim 1, wherein the standard deviation σ of the cos θ is more than 0.00 and 0.01 or less. ### Claim 4 (depends on 1) The magnetic tape according to claim 1, wherein a fluorine-containing compound is included in a portion on the non-magnetic support on a magnetic layer side. ### Claim 5 (depends on 1) The magnetic tape according to claim 1, further comprising: a non-magnetic layer containing a non-magnetic powder between the non-magnetic support and the magnetic layer. ### Claim 6 (depends on 5) The magnetic tape according to claim 5, wherein the non-magnetic powder includes an Fe-based inorganic oxide powder having an average particle volume of 2.0×10−6 μm3 or less. ### Claim 7 (depends on 5) The magnetic tape according to claim 5, wherein the non-magnetic powder includes carbon black having a pH of 9.0 or less. ### Claim 8 (depends on 5) The magnetic tape according to claim 5, wherein a thickness of the non-magnetic layer is 0.1 μm or more and 0.7 μm or less. ### Claim 9 (depends on 1) The magnetic tape according to claim 1, further comprising: a back coating layer containing a non-magnetic powder on a surface side of the non-magnetic support opposite to a surface side having the magnetic layer. ### Claim 10 (depends on 1) The magnetic tape according to claim 1, wherein a tape thickness is 5.2 μm or less. ### Claim 11 (depends on 1) The magnetic tape according to claim 1, wherein a tape thickness is 5.0 μm or less. ### Claim 12 (depends on 1) The magnetic tape according to claim 1, wherein a vertical squareness ratio of the magnetic tape is 0.60 or more. ### Claim 13 (depends on 1) The magnetic tape according to claim 1, wherein a vertical squareness ratio of the magnetic tape is 0.65 or more. ### Claim 14 (depends on 1) The magnetic tape according to claim 1, wherein the standard deviation σ of the cos θ is more than 0.00 and 0.01 or less, a fluorine-containing compound is included in a portion on the non-magnetic support on a magnetic layer side, the magnetic tape further includes a non-magnetic layer containing a non-magnetic powder between the non-magnetic support and the magnetic layer, the non-magnetic powder includes an Fe-based inorganic oxide powder having an average particle volume of 2.0×10−6 μm3 or less and carbon black having a pH of 9.0 or less, a thickness of the non-magnetic layer is 0.1 μm or more and 0.7 μm or less, the magnetic tape further includes a back coating layer containing a non-magnetic powder on a surface side of the non-magnetic support opposite to a surface side having the magnetic layer, a tape thickness is 5.0 μm or less, and a vertical squareness ratio of the magnetic tape is 0.65 or more. ### Claim 15 (depends on 1) A magnetic tape cartridge comprising: the magnetic tape according to claim 1. ### Claim 16 (depends on 1) A magnetic tape apparatus comprising: the magnetic tape according to claim 1. ### Claim 17 (depends on 16) The magnetic tape apparatus according to claim 16, further comprising: a magnetic head, wherein the magnetic head has a module including an element array with a plurality of magnetic head elements between a pair of servo signal reading elements, and the magnetic tape apparatus changes an angle θ formed by an axis of the element array with respect to a width direction of the magnetic tape during running of the magnetic tape in the magnetic tape apparatus.