MAGNETIC TAPE AND MAGNETIC TAPE DEVICE

• US 20170372742A1
• Filed: 06/19/2017
• Published: 12/28/2017
• Est. Priority Date: 06/23/2016
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: KANEKO, Tetsuya, KASADA, Norihito, OZAWA, Eiki
• Granted Patent: US 10,510,369 B2
• Time in Patent Office: Days
• CPC Class Codes: G11B 5/584 for track following on tapes
• CPC Class Codes: G11B 5/70 on a base layer
• CPC Class Codes: G11B 5/7013 characterised by the dispersing agent
• CPC Class Codes: G11B 5/70678 Ferrites
• CPC Class Codes: G11B 5/708 characterised by addition of non-magnetic particles to the layer
• CPC Class Codes: G11B 5/7085 non-magnetic abrasive particles
• CPC Class Codes: G11B 5/73 Base layers , i.e. all non-magnetic layers lying under a lowermost magnetic recording layer, e.g. including any non-magnetic layer in between a first magnetic recording layer and either an underlying substrate or a soft magnetic underlayer
• CPC Class Codes: G11B 5/78 Tape carriers

Abstract

The magnetic tape includes a non-magnetic support; a non-magnetic layer including non-magnetic powder and a binder on the non-magnetic support; and a magnetic layer including ferromagnetic powder and a binder on the non-magnetic layer, in which the total thickness of the non-magnetic layer and the magnetic layer is equal to or smaller than 0.60 μm, the magnetic layer includes a timing-based servo pattern, the ferromagnetic powder is ferromagnetic hexagonal ferrite powder, the magnetic layer includes an abrasive, and a tilt cos η of the ferromagnetic hexagonal ferrite powder with respect to a surface of the magnetic layer acquired by cross section observation performed by using a scanning transmission electron microscope is 0.85 to 1.00.

Claims

1. A magnetic tape comprising:

a non-magnetic support;

a non-magnetic layer including non-magnetic powder and a binder on the non-magnetic support; and

a magnetic layer including ferromagnetic powder and a binder on the non-magnetic layer,

wherein the total thickness of the non-magnetic layer and the magnetic layer is equal to or smaller than 0.60 μ

m,

the magnetic layer includes a timing-based servo pattern,

the ferromagnetic powder is ferromagnetic hexagonal ferrite powder,

the magnetic layer includes an abrasive, and

a tilt cos θ

of the ferromagnetic hexagonal ferrite powder with respect to a surface of the magnetic layer acquired by cross section observation performed by using a scanning transmission electron microscope is 0.85 to 1.00.

2. The magnetic tape according to claim 1,

wherein the cos θ

is 0.89 to 1.00.

3. The magnetic tape according to claim 1,

wherein the cos θ

is 0.95 to 1.00.

4. The magnetic tape according to claim 1,

wherein the magnetic layer further includes a polyester chain-containing compound having a weight-average molecular weight of 1,000 to 80,000.

5. The magnetic tape according to claim 1,

wherein an activation volume of the ferromagnetic hexagonal ferrite powder is 800 nm³ to 2,500 nm³.

6. The magnetic tape according to claim 1,

wherein the total thickness of the non-magnetic layer and the magnetic layer is 0.20 μ

m to 0.60 μ

m.

7. The magnetic tape according to claim 1,

wherein the abrasive includes alumina powder.

8. A magnetic tape device comprising:

a magnetic tape,

a magnetic head; and

a servo head, wherein

the magnetic tape is a magnetic tape comprising;

a non-magnetic support;

a non-magnetic layer including non-magnetic powder and a binder on the non-magnetic support; and

a magnetic layer including ferromagnetic powder and a binder on the non-magnetic layer,

wherein the total thickness of the non-magnetic layer and the magnetic layer is equal to or smaller than 0.60 μ

m,

the magnetic layer includes a timing-based servo pattern,

the ferromagnetic powder is ferromagnetic hexagonal ferrite powder,

the magnetic layer includes an abrasive, and

a tilt cos θ

of the ferromagnetic hexagonal ferrite powder with respect to a surface of the magnetic layer acquired by cross section observation performed by using a scanning transmission electron microscope is 0.85 to 1.00.

9. The magnetic tape device according to claim 8,

wherein the cos θ

is 0.89 to 1.00.

10. The magnetic tape device according to claim 8,

wherein the cos θ

is 0.95 to 1.00.

11. The magnetic tape device according to claim 8,

wherein the magnetic layer further includes a polyester chain-containing compound having a weight-average molecular weight of 1,000 to 80,000.

12. The magnetic tape device according to claim 8,

wherein an activation volume of the ferromagnetic hexagonal ferrite powder is 800 nm³ to 2,500 nm³.

13. The magnetic tape device according to claim 8,

wherein the total thickness of the non-magnetic layer and the magnetic layer of the magnetic tape is 0.20 μ

m to 0.60 μ

m.

14. The magnetic tape device according to claim 8,

wherein the abrasive includes alumina powder.