MAGNETIC TAPE

• US 20170372738A1
• Filed: 06/13/2017
• Published: 12/28/2017
• Est. Priority Date: 06/22/2016
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: KASADA, Norihito
• Granted Patent: US 10,477,072 B2
• Time in Patent Office: Days
• CPC Class Codes: G11B 5/00813 magnetic tapes
• CPC Class Codes: G11B 5/627 of leaders for magnetic tapes, e.g. non-magnetic strips on the tapes or for connection
• CPC Class Codes: G11B 5/7013 characterised by the dispersing agent
• CPC Class Codes: G11B 5/70605 metals or alloys
• CPC Class Codes: G11B 5/70678 Ferrites
• CPC Class Codes: G11B 5/7085 non-magnetic abrasive particles
• CPC Class Codes: G11B 5/71 characterised by the lubricant
• CPC Class Codes: G11B 5/735 characterised by the back layer magnetic recording media substrates G11B5/739
• CPC Class Codes: G11B 5/78 Tape carriers
• CPC Class Codes: G11B 5/8404 manufacturing base layers
• CPC Class Codes: H04N 1/405 Halftoning, i.e. converting the picture signal of a continuous-tone original into a corresponding signal showing only two levels
• CPC Class Codes: H04N 1/4053 with threshold modulated relative to input image data or vice versa
• CPC Class Codes: H04N 1/52 Circuits or arrangements for halftone screening
• CPC Class Codes: H04N 1/58 Edge or detail enhancement; Noise or error suppression, e.g. colour misregistration correction H04N1/62 takes precedence

Abstract

Provided is a magnetic tape in which ferromagnetic powder included in a magnetic layer is ferromagnetic hexagonal ferrite powder having an activation volume equal to or smaller than 1,600 nm³, the magnetic layer includes one or more components selected from the group consisting of fatty acid and fatty acid amide, and an abrasive, a C—H derived C concentration calculated from a C—H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is equal to or greater than 45 atom %, and a tilt cos θ of the ferromagnetic hexagonal ferrite powder with respect to the 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; and

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

wherein the ferromagnetic powder is ferromagnetic hexagonal ferrite powder having an activation volume equal to or smaller than 1,600 nm³,

the magnetic layer includes one or more components selected from the group consisting of fatty acid and fatty acid amide, and an abrasive,

a C—

H derived C concentration calculated from a C—

H peak area ratio of C1s spectra obtained by X-ray photoelectron spectroscopic analysis performed on the surface of the magnetic layer at a photoelectron take-off angle of 10 degrees is equal to or greater than 45 atom %, and

a tilt cos θ

of the ferromagnetic hexagonal ferrite powder with respect to the 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 C—

H derived C concentration is 45 atom % to 80 atom %.

3. The magnetic tape according to claim 1,

wherein the C—

H derived C concentration is 50 atom % to 80 atom %.

4. The magnetic tape according to claim 1,

wherein the activation volume of the ferromagnetic hexagonal ferrite powder is 800 nm³ to 1,600 nm³.

5. The magnetic tape according to claim 2,

wherein the activation volume of the ferromagnetic hexagonal ferrite powder is 800 nm³ to 1,600 nm3.

6. The magnetic tape according to claim 3,

wherein the activation volume of the ferromagnetic hexagonal ferrite powder is 800 nm³ to 1,600 nm³.

7. The magnetic tape according to claim 1,

wherein the abrasive includes alumina powder.

8. 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.

9. The magnetic tape according to claim 2,

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

10. The magnetic tape according to claim 3,

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

11. The magnetic tape according to claim 4,

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 according to claim 5,

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

13. The magnetic tape according to claim 6,

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

14. The magnetic tape according to claim 7,

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

15. The magnetic tape according to claim 1, further comprising:

a non-magnetic layer including non-magnetic powder and a binder between the non-magnetic support and the magnetic layer.

16. The magnetic tape according to claim 15,

wherein magnetic layer and the non-magnetic layer respectively include one or more components selected from the group consisting of fatty acid and fatty acid amide.