IP Library Granted Patent US 11,894,033
Granted Patent B2
US 11,894,033 · App. 17/954,800 · Granted Feb 6, 2024

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

Inventor: Norihito Kasada (Minamiashigara, JP)
Assignee: FUJIFILM Corporation
G11B5/7334G11B5/78
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Quick Facts
Patent No.
US 11,894,033
App. No.
17/954,800
Granted
Feb 6, 2024
Kind
B2
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 32° C. and a relative humidity of 80%, a frictional force F 45 ° 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.

Claims (51)

1. A magnetic tape comprising:

a non-magnetic support; and

a magnetic layer containing a ferromagnetic powder,

wherein a vertical switching field distribution SFD of the magnetic tape is 1.5 or less, and

in an environment with a temperature of 32° C. and a relative humidity of 80%,

a frictional force F 45 ° on a 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.

2. The magnetic tape according to claim 1 ,

wherein the standard deviation of F is 2 gf to 10 gf.

3. The magnetic tape according to claim 1 ,

wherein the vertical switching field distribution SFD of the magnetic tape is 0.5 to 1.5.

4. 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.

5. The magnetic tape according to claim 1 ,

wherein the magnetic layer contains inorganic oxide-based particles.

6. The magnetic tape according to claim 5 ,

wherein the inorganic oxide-based particles are composite particles of an inorganic oxide and a polymer.

7. The magnetic tape according to claim 1 ,

wherein the magnetic layer contains carbon black.

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 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.

10. The magnetic tape according to claim 1 ,

wherein a tape thickness is 5.2 μm or less.

11. The magnetic tape according to claim 1 ,

wherein the standard deviation of F is 2 gf to 10 gf,

the vertical switching field distribution SFD of the magnetic tape is 0.5 to 1.5,

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

the magnetic layer contains composite particles of an inorganic oxide and a polymer,

the magnetic tape further comprises:

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

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, and

a tape thickness is 5.2 μm or less.

12. The magnetic tape according to claim 1 ,

wherein the standard deviation of F is 2 gf to 10 gf,

the vertical switching field distribution SFD of the magnetic tape is 0.5 to 1.5,

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

the magnetic layer contains carbon black,

the magnetic tape further comprises:

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

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, and

a tape thickness is 5.2μm or less.

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 having an element array including 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 a 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 061243/0632 →
Priority Claims (1)
JP 2021-158782 · Sep 29, 2021 · national
Continuity (1)
Related Publication 20230106585A1 · Apr 6, 2023
Cited By (3)
US 12,300,287 US 12,308,057 US 12,308,059