Magnetic recording medium

• US 20050260456A1
• Filed: 05/19/2005
• Published: 11/24/2005
• Est. Priority Date: 05/19/2004
• Status: Abandoned Application

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Matsumoto, Ayako, Hanai, Kazuko
• Application Number:
  US11/132,405
• Publication Number:
  US 20050260456A1
• Time in Patent Office: Days
• US Class Current: 428/840.100
• 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 5/7368 Non-polymeric layer under the lowermost magnetic recording layer base layers having a non-magnetic layer under a soft magnetic layer G11B5/736; magnetic recording media substrates G11B5/739
• CPC Class Codes: G11B 5/73927 Polyester substrates, e.g. polyethylene terephthalate
• CPC Class Codes: G11B 5/73929 comprising naphthalene ring compounds, e.g. polyethylene naphthalate substrates
• CPC Class Codes: G11B 5/73935 characterised by roughness or surface features, e.g. by added particles

Abstract

A magnetic recording medium comprising: a nonmagnetic support; and a magnetic layer containing ferromagnetic powder and a binder, wherein the nonmagnetic support contains polyester, the nonmagnetic support has gauche/trans peak intensity ratio of 0.50 or less as determined by a ATR-FT-IR method, and a shrinkage percentage of the magnetic recording medium after storage for 1 week under a conditions of 70° C. and 5% RH is 0.040% or less.

Claims

1. A magnetic recording medium comprising:

a nonmagnetic support; and

a magnetic layer containing ferromagnetic powder and a binder, wherein the nonmagnetic support contains polyester, the nonmagnetic support has gauche/trans peak intensity ratio of 0.50 or less as determined by a ATR-FT-IR method, and a shrinkage percentage of the magnetic recording medium after storage for 1 week under a conditions of 70°

C. and 5% RH is 0.040% or less.

2. The magnetic recording medium according to claim 1, further comprising a substantially nonmagnetic lower layer between the magnetic layer and the nonmagnetic support.

3. The magnetic recording medium according to claim 2, wherein the substantially nonmagnetic lower layer contains a binder and nonmagnetic powder.

4. The magnetic recording medium according to claim 1, wherein the nonmagnetic support contains polyethylene naphthalate.

5. The magnetic recording medium according to claim 2, wherein the nonmagnetic support contains polyethylene naphthalate.

6. The magnetic recording medium according to claim 1, wherein the nonmagnetic support further contains a filler.

7. The magnetic recording medium according to claim 1, wherein the nonmagnetic support has a thickness of from 10 to 100 μ

m.

8. The magnetic recording medium according to claim 1, wherein the nonmagnetic support has a thickness of from 20 to 80 μ

m.

9. The magnetic recording medium according to claim 1, wherein the nonmagnetic support has a central line average surface roughness of 8 nm or less.

10. The magnetic recording medium according to claim 1, wherein the nonmagnetic support has a central line average surface roughness of 6 nm or less.