Magnetic recording medium, magnetic tape cartridge, and magnetic recording and reproducing device

Patent metadata

Field	Value
Publication number	US-2023386515-A1
Application number	US-202318449307-A
Country	US
Kind code	A1
Filing date	Aug 14, 2023
Priority date	Feb 26, 2021
Publication date	Nov 30, 2023
Grant date	—

Abstract

Provided are a magnetic recording medium including a non-magnetic support, and a magnetic layer including a ferromagnetic powder. The ferromagnetic powder is an ε-iron oxide powder, and an intensity ratio (Int1/Int2) of diffraction intensities obtained by an X-ray diffraction analysis of the magnetic layer using an In-Plane method is 1.0 or more and 6.5 or less; and a magnetic tape cartridge and a magnetic recording and reproducing device each including the magnetic recording medium.

First claim

What is claimed is:

1 . A magnetic recording medium comprising:
a non-magnetic support; and a magnetic layer containing a ferromagnetic powder, wherein the ferromagnetic powder is an ε-iron oxide powder, Int1/Int2, which is an intensity ratio of diffraction intensities obtained by an X-ray diffraction analysis of the magnetic layer using an In-Plane method, is 1.0 or more and 6.5 or less, the Int1 is a maximum value of a diffraction intensity in a range in which a diffraction angle2θ χ is 29.0° or more and 31.0° or less, and the Int2 is a maximum value of a diffraction intensity in a range in which the diffraction angle2θ χ is 36.3° or more and 37.5° or less.

2 . The magnetic recording medium according to claim 1 ,
wherein the intensity ratio is 1.5 or more and 6.0 or less.

3 . The magnetic recording medium according to claim 1 ,
wherein the intensity ratio is 3.0 or more and 5.5 or less.

4 . The magnetic recording medium according to claim 1 ,
wherein the ε-iron oxide powder contains a cobalt element.

5 . The magnetic recording medium according to claim 4 ,
wherein the ε-iron oxide powder further contains an element selected from the group consisting of a gallium element and an aluminum element.

6 . The magnetic recording medium according to claim 4 ,
wherein the ε-iron oxide powder further contains a titanium element.

7 . The magnetic recording medium according to claim 1 , further comprising:
a non-magnetic layer containing a non-magnetic powder between the non-magnetic support and the magnetic layer.

8 . The magnetic recording medium 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 on which the magnetic layer is provided.

9 . The magnetic recording medium according to any claim 1 ,
wherein the magnetic recording medium is a magnetic tape.

10 . A magnetic tape cartridge comprising:
the magnetic tape according to claim 9 .

11 . The magnetic tape cartridge according to claim 10 ,
wherein the intensity ratio is 1.5 or more and 6.0 or less.

12 . The magnetic tape cartridge according to claim 10 ,
wherein the intensity ratio is 3.0 or more and 5.5 or less.

13 . The magnetic tape cartridge according to claim 10 ,
wherein the ε-iron oxide powder contains a cobalt element.

14 . The magnetic tape cartridge according to claim 13 ,
wherein the ε-iron oxide powder further contains an element selected from the group consisting of a gallium element and an aluminum element.

15 . The magnetic tape cartridge according to claim 13 ,
wherein the ε-iron oxide powder further contains a titanium element.

16 . The magnetic tape cartridge according to claim 10 ,
wherein the magnetic tape further comprises: a non-magnetic layer containing a non-magnetic powder between the non-magnetic support and the magnetic layer.

17 . The magnetic recording medium according to claim 10 ,
wherein the magnetic tape further comprises: a back coating layer containing a non-magnetic powder on a surface side of the non-magnetic support opposite to a surface side on which the magnetic layer is provided.

18 . A magnetic recording and reproducing device comprising:
the magnetic recording medium according to claim 1 .

Assignees

• Fujifilm Corp

Inventors

• Fujimoto Takashi
• Ozawa Eiki

Classifications

• G11B5/70621 Primary

  containing Co metal or alloys · CPC title

• G11B5/70642 Primary

  iron oxides · CPC title

• G11B5/7356

  comprising non-magnetic particles in the back layer, e.g. particles of TiO2, ZnO or SiO2 · CPC title

• G11B5/7021

  containing a polyurethane or a polyisocyanate · CPC title

• G11B5/78 Primary

  Tape carriers · CPC title