Magnetic recording medium

• US 20060008681A1
• Filed: 07/07/2005
• Published: 01/12/2006
• Est. Priority Date: 07/08/2004
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Hashimoto, Hiroshi, Murayama, Yuichiro
• Granted Patent: US 7,553,565 B2
• Time in Patent Office: Days
• US Class Current: 428/840.200
• CPC Class Codes: G11B 5/7013 characterised by the dispersing agent
• CPC Class Codes: G11B 5/7021 containing a polyurethane or a polyisocyanate
• CPC Class Codes: G11B 5/714 characterised by the dimension of the magnetic particles
• CPC Class Codes: G11B 5/733 characterised by the addition of non-magnetic particles base layers having a non-magnetic layer under a soft magnetic layer G11B5/736; magnetic recording media substrates G11B5/739
• CPC Class Codes: G11B 5/7334 Base layer characterised by composition or structure
• CPC Class Codes: Y10T 428/31609 Particulate metal or metal compound-containing

Abstract

A magnetic recording medium is provided that includes a support and at least one magnetic layer provided on or above the support, the magnetic layer including a ferromagnetic powder dispersed in a binder and at least one type of compound selected from Formulae (I) to (III) below; (in Formulae (I) to (III), each R independently denotes an alkyl group having 1 to 20 carbons).

Claims

1. A magnetic recording medium comprising:

a support; and

at least one magnetic layer provided on or above the support, the magnetic layer comprising a ferromagnetic powder dispersed in a binder and at least one type of compound selected from Formulae (I) to (III) below;

(in Formulae (I) to (III), each R independently denotes an alkyl group having 1 to 20 carbons).

3. The magnetic recording medium according to claim 1, wherein the magnetic layer comprises at least one type of compound selected from Formulae (I) to (III) below;

5. The magnetic recording medium according to claim 1, wherein the magnetic layer comprises a compound of Formula (I) below;

8. The magnetic recording medium according to claim 1, wherein the magnetic layer comprises 0.1 to 15 parts by weight of at least one type of compound selected from Formulae (I) to (III) relative to 100 parts by weight of ferromagnetic powder.

10. The magnetic recording medium according to claim 1, wherein there are 5 to 1,000/100 (μ

m)² magnetic layer surface micro projections having a height of 10 to 20 nm measured by atomic force microscopy (AFM).

12. The magnetic recording medium according to claim 1, wherein there are 5 to 100/100 (μ

m)² magnetic layer surface micro projections having a height of 10 to 20 nm measured by atomic force microscopy (AFM).

14. The magnetic recording medium according to claim 1, wherein the binder is polyurethane.

16. The magnetic recording medium according to claim 1, wherein the ferromagnetic powder is an acicular ferromagnetic substance having a major-axis length of 25 to 60 nm or a tabular magnetic substance having a plate size of 10 to 50 nm.

2. A magnetic recording medium comprising:

a support;

a nonmagnetic layer provided on or above the support, the nonmagnetic layer comprising a nonmagnetic powder dispersed in a binder; and

at least one magnetic layer provided on the nonmagnetic layer, the magnetic layer comprising a ferromagnetic powder dispersed in a binder, and the nonmagnetic layer and/or the magnetic layer comprising at least one type of compound selected from Formulae (I) to (III) below;

(in Formulae (I) to (III), each R independently denotes an alkyl group having 1 to 20 carbons).

4. The magnetic recording medium according to claim 2, wherein the nonmagnetic layer and/or the magnetic layer comprises at least one type of compound selected from Formulae (I) to (III) below;

6. The magnetic recording medium according to claim 2, wherein the nonmagnetic layer and/or the magnetic layer comprises a compound of Formula (I) below;

7. The magnetic recording medium according to claim 2, wherein the magnetic layer comprises 0.1 to 15 parts by weight of at least one type of compound selected from Formulae (I) to (III) relative to 100 parts by weight of ferromagnetic powder.

9. The magnetic recording medium according to claim 2, wherein the nonmagnetic layer comprises 0.1 to 15 parts by weight of at least one type of compound selected from Formulae (I) to (III) relative to 100 parts by weight of nonmagnetic powder.

11. The magnetic recording medium according to claim 2, wherein there are 5 to 1,000/100 (μ

m)² magnetic layer surface micro projections having a height of 10 to 20 nm measured by atomic force microscopy (AFM).

13. The magnetic recording medium according to claim 2, wherein there are 5 to 100/100 (μ

m)² magnetic layer surface micro projections having a height of 10 to 20 nm measured by atomic force microscopy (AFM).

15. The magnetic recording medium according to claim 2, wherein the binder is polyurethane.

17. The magnetic recording medium according to claim 2, wherein the ferromagnetic powder is an acicular ferromagnetic substance having a major axis length of 25 to 60 nm or a tabular magnetic substance having a plate size of 10 to 50 nm.