IP Library Granted Patent US 11,869,558
Granted Patent B2
US 11,869,558 · App. 17/955,035 · Granted Jan 9, 2024

Magnetic tape having characterized magnetic layer surface, magnetic tape cartridge, and magnetic tape device

Inventor: Norihito Kasada (Minamiashigara, JP)
Assignee: FUJIFILM Corporation
G11B5/7356G11B5/7085G11B5/78
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Quick Facts
Patent No.
US 11,869,558
App. No.
17/955,035
Granted
Jan 9, 2024
Kind
B2
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 23° C. and a relative humidity of 50%, an AlFeSil abrasion value 45° 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.

Claims (38)

1. A magnetic tape comprising:

a non-magnetic support; and

a magnetic layer containing a ferromagnetic powder,

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

in an environment with a temperature of 23° C. and a relative humidity of 50%,

an AlFeSil abrasion value 45° 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.

2. The magnetic tape according to claim 1 ,

wherein the standard deviation of the AlFeSil abrasion value is 15 μm to 30 μm.

3. The magnetic tape according to claim 1 ,

wherein the tape thickness is 4.0 μm to 5.2 μm.

4. The magnetic tape according to claim 1 ,

wherein the tape thickness is 4.0 μm to 5.0 μm.

5. The magnetic tape according to claim 1 ,

wherein a standard deviation of curvature of the magnetic tape in a longitudinal direction is 5 mm/m or less.

6. The magnetic tape according to claim 1 ,

wherein the magnetic layer contains one or more kinds of non-magnetic powder.

7. The magnetic tape according to claim 6 ,

wherein the non-magnetic powder includes an alumina powder.

8. 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.

9. The magnetic tape according to claim 8 ,

wherein a thickness of the non-magnetic layer is 0.1 μm to 0.7 μm.

10. 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 provided with the magnetic layer.

11. The magnetic tape device according to claim 1 ,

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

12. The magnetic tape device according to claim 1 ,

wherein a vertical squareness ratio of the magnetic tape is 0.65 or more.

13. A magnetic tape cartridge comprising:

the magnetic tape according to claim 1 .

14. A magnetic tape device comprising:

the magnetic tape according to claim 1 .

15. The magnetic tape device according to claim 14 , further comprising:

a magnetic head,

wherein the magnetic head includes a module including an element array having a plurality of magnetic head elements between a pair of servo signal reading elements, and

the magnetic tape device changes an angle θ formed by an axis of the element array with respect to the width direction of the magnetic tape during running of the magnetic tape in the magnetic tape device.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 28, 2022
From: KASADA, NORIHITO
To: FUJIFILM CORPORATION
Reel/Frame 061246/0041 →
Priority Claims (2)
JP 2021-158788 · Sep 29, 2021 · national
JP 2022-145715 · Sep 14, 2022 · national
Continuity (1)
Related Publication 20230103562A1 · Apr 6, 2023
Cited By (12)
US 12,300,276 US 12,300,286 US 12,300,287 US 12,300,288 US 12,308,054 US 12,308,057 US 12,308,058 US 12,308,059 US 12,308,060 US 12,322,425 US 12,334,125 US 12,380,924