IP Library › Granted Patent US 12,374,368
Granted Patent B2
US 12,374,368 · App. 18/330,717 · Granted Jul 29, 2025

Magnetic tape apparatus, magnetic tape, and magnetic tape cartridge

Inventor: Norihito Kasada (Minamiashigara, JP)
Assignee: FUJIFILM Corporation
G11B23/107B65H23/04B65H23/105B65H23/1806G11B5/70G11B5/708G11B5/73G11B5/735G11B5/78G11B15/43G11B23/027G11B23/04
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Quick Facts
Patent No.
US 12,374,368
App. No.
18/330,717
Granted
Jul 29, 2025
Kind
B2
Abstract

Provided is a magnetic tape apparatus in which the magnetic tape is run between a winding reel and a cartridge reel in a state where a tension is applied in a longitudinal direction, a maximum value of the tension is 0.50 N or more, the magnetic tape after being run in a state where the tension is applied is wound around the cartridge reel with a tension of 0.30 N or less applied in the longitudinal direction, and the number of recesses existing on a surface of the magnetic layer of the magnetic tape and having an equivalent circle diameter of 0.10 μm or more and less than 0.20 μm is 100 or more and 2000 or less per an area of 40 μm×40 μm.

Claims (47)

1. A magnetic tape apparatus comprising:

a winding reel;

a magnetic tape; and

a magnetic tape cartridge having a cartridge reel,

wherein, in the magnetic tape apparatus,

the magnetic tape is run between the winding reel and the 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,

the magnetic tape after being run in a state where the tension is applied is wound around the cartridge reel with a tension of 0.30 N or less applied in the longitudinal direction of the magnetic tape,

the magnetic tape includes a non-magnetic support, and a magnetic layer containing a ferromagnetic powder, and

a number of recesses existing on a surface of the magnetic layer and having an equivalent circle diameter of 0.10 μm or more and less than 0.20 μm, is 100 or more and 2000 or less per an area of 40 μm×40 μm.

2. The magnetic tape apparatus according to claim 1 ,

wherein the tension applied in the longitudinal direction of the magnetic tape is changed during the running.

3. The magnetic tape apparatus according to claim 2 ,

wherein a tape thickness of the magnetic tape is 5.2 μm or less.

4. The magnetic tape apparatus according to claim 3 ,

wherein a vertical squareness ratio of the magnetic tape is 0.60 or more.

5. The magnetic tape apparatus according to claim 2 ,

wherein a vertical squareness ratio of the magnetic tape is 0.60 or more.

6. The magnetic tape apparatus according to claim 1 ,

wherein a tape thickness of the magnetic tape is 5.2 μm or less.

7. The magnetic tape apparatus according to claim 6 ,

wherein a vertical squareness ratio of the magnetic tape is 0.60 or more.

8. The magnetic tape apparatus according to claim 1 ,

wherein the magnetic tape further includes a non-magnetic layer containing a non-magnetic powder between the non-magnetic support and the magnetic layer.

9. The magnetic tape apparatus according to claim 1 ,

wherein 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.

10. The magnetic tape apparatus according to claim 9 ,

wherein the non-magnetic powder of the back coating layer includes carbon black.

11. The magnetic tape apparatus according to claim 1 ,

wherein a vertical squareness ratio of the magnetic tape is 0.60 or more.

12. A magnetic tape,

which is used in a magnetic tape apparatus in which the magnetic tape is run between a winding reel and a cartridge reel of a magnetic tape cartridge in a state where a tension is applied in a longitudinal direction of the magnetic tape, a maximum value of the tension is 0.50 N or more, and the magnetic tape after being run in a state where the tension is applied is wound around the cartridge reel with a tension of 0.30 N or less applied in the longitudinal direction of the magnetic tape, the magnetic tape comprising:

a non-magnetic support; and

a magnetic layer containing a ferromagnetic powder,

wherein the number of recesses existing on a surface of the magnetic layer and having an equivalent circle diameter of 0.10 μm or more and less than 0.20 μm, is 100 or more and 2000 or less per an area of 40 μm×40 μm.

13. The magnetic tape according to claim 12 ,

wherein the tension applied in the longitudinal direction of the magnetic tape is changed during the running.

14. The magnetic tape according to claim 12 ,

wherein a tape thickness is 5.2 μm or less.

15. The magnetic tape according to claim 12 , further comprising:

a non-magnetic layer containing a non-magnetic powder between the non-magnetic support and the magnetic layer.

16. The magnetic tape according to claim 12 , 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.

17. The magnetic tape according to claim 16 ,

wherein the non-magnetic powder of the back coating layer includes carbon black.

18. The magnetic tape according to claim 12 ,

wherein a vertical squareness ratio is 0.60 or more.

19. A magnetic tape cartridge in which the magnetic tape according to claim 12 is accommodated by being wound around a cartridge reel.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jun 8, 2023
From: KASADA, NORIHITO
To: FUJIFILM CORPORATION
Reel/Frame 063890/0714 →
Priority Claims (1)
JP 2020-214225 · Dec 23, 2020 · national
Continuity (2)
Continuation PCTJP2021045966 · Dec 14, 2021
Related Publication 20240013807A1 · Jan 11, 2024
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