Oriented body, method for producing the same, device for producing the same, and magnetic recording medium

Patent metadata

Field	Value
Publication number	US-2018366151-A1
Application number	US-201615780057-A
Country	US
Kind code	A1
Filing date	Nov 30, 2016
Priority date	Nov 30, 2015
Publication date	Dec 20, 2018
Grant date	—

Abstract

There is provided an oriented body containing platinum group-substituted-6 iron oxide particles typified by Rh-substituted ϵ-iron oxide or Ru-substituted ϵ-iron oxide applicable to MAMR, MIMR, or F-MIMR system, and a technique related thereto, containing platinum group element-substituted ϵ-iron oxide particles in which a part of ϵ-iron oxide is substituted with at least one element of platinum group elements, as magnetic particles wherein the degree of orientation of the magnetic particles defined by the degree of orientation=SQ (direction of magnetization easy-axes)/SQ (direction of magnetization hard-axes) exceeds 5.0, and a coercive force exceeds 31 kOe.

First claim

1 . An oriented body containing platinum group element-substituted ϵ-iron oxide particles in which a part of ϵ-iron oxide is substituted with at least one element of platinum group elements, as magnetic particles
wherein the degree of orientation of the magnetic particles defined by the degree of orientation=SQ (direction of magnetization easy-axes)/SQ (direction of magnetization hard-axes) exceeds 5.0, and a coercive force exceeds 31 kOe.

2 . The oriented body according to claim 1 , wherein the platinum group element is rhodium (Rh) or ruthenium (Ru).

3 . A method for producing an oriented body, comprising:
injecting a mixed solution in which platinum group element-substituted ϵ-iron oxide particles are dispersed, into a region partitioned by a partition frame on a predetermined base, wherein the platinum group element-substituted ϵ-iron oxide particles are obtained by substituting a part of ϵ-iron oxide with at least one element of platinum group elements; and removing a solvent of the mixed solution while applying a magnetic field to the region to obtain an oriented body.

4 . A device for producing an oriented body having a function of:
injecting a mixed solution in which platinum group element-substituted E-iron oxide particles are dispersed, into a region partitioned by a partition frame on a predetermined base, wherein the platinum group element-substituted E-iron oxide particles are obtained by substituting a part of E-iron oxide with at least one element of platinum group elements; and removing a solvent of the mixed solution while applying a magnetic field to the region to obtain an oriented body.

5 . A magnetic recording medium, for microwave assisted magnetic recording (MAMR), millimeter wave assisted magnetic recording (MIMR) or focused millimeter wave resonance magnetic recording (F-MIMR) in which the oriented body of claim 1 is used.

6 . A magnetic recording medium using an oriented body containing epsilon type iron oxide substituted with a metal element, in which a millimeter wave absorption performance is utilized, which is generated due to a natural resonance of the epsilon type iron oxide which is a magnetic material to be used, and a magnetic recording mode is millimeter wave assisted magnetic recording (MIMR) or focused millimeter wave resonance magnetic recording (F-MIMR).

7 . An oriented body containing Rh-substituted ϵ-iron oxide particles in which a part of ϵ-iron oxide is substituted with rhodium (Rh) as magnetic particles,
wherein the degree of orientation of the magnetic particles defined by the degree of orientation=SQ (direction of magnetization easy-axes)/SQ (direction of magnetization hard-axes) exceeds 3.5, and
a coercive force exceeds 31 kOe.

8 . A magnetic recording medium, for microwave assisted magnetic recording (MAMR), millimeter wave assisted magnetic recording (MIMR) or focused millimeter wave resonance magnetic recording (F-MIMR) in which the oriented body of claim 2 is used.

Assignees

• Univ Tokyo
• Dowa Electronics Materials Co Ltd

Inventors

• Ohkoshi Shin-Ichi
• Imoto Kenta
• ANAN Shizuka
• Namai Asuka
• Masada Kenji

Classifications

• H01F1/11

  in the form of particles {(for magnetic record carriers G11B5/70626)} · CPC title

• C01G49/00

  Compounds of iron · CPC title

• C01P2006/42

  Magnetic properties · CPC title

• G11B5/70605 Primary

  metals or alloys · CPC title

• G11B2005/0024

  Microwave assisted recording · CPC title