US 7,611,783 B2 · Magnetic recording medium and magnetic recording device

Abstract

A magnetic recording medium includes; a base member; an underlayer formed on the base member; a main recording layer formed on the underlayer, and a writing assist layer formed on or under the main recording layer in contact with the main recording layer. The main recording layer has perpendicular magnetic anisotropy with an anisotropic magnetic field of Hk1 and an inclination of a reversal part of a magnetization curve of a1. The writing assist layer has an anisotropic magnetic field of Hk2 and an inclination of a reversal part of a magnetization curve of a2. The anisotropic magnetic fields Hk1 and Hk2 and the inclinations a1 and a2 satisfy Hk1>Hk2 and a2>a1.

Claims20

Dependent claims

A magnetic recording medium, comprising:

a base member;
an underlayer formed on the base member;
a main recording layer formed on the underlayer, the main recording layer having perpendicular magnetic anisotropy with an anisotropic magnetic field of Hk1 and an inclination of a reversal part of a magnetization curve of a1;
and
a writing assist layer formed on or under the main recording layer in contact with the main recording layer, the writing assist layer having an anisotropic magnetic field of Hk2 and an inclination of a reversal part of a magnetization curve of a2,
wherein the anisotropic magnetic fields Hk1 and Hk2 and the inclinations a1 and a2 satisfy Hk1>Hk2 and a2>a1.

3 more elements

Dependencies are inferred from the claim text.

Facts

Application

11/374,424Filed 14 Mar 2006 · continuation in part

Priority

JP 2005-10476631 Mar 2005

Published

US 2006/0222900 A15 Oct 2006

Granted

3 Nov 2009

Term ends

Not estimatedThe source records don’t support an estimate.

Classification5 codes

G11B 5/672
The record carriers consisting of several layers: having different compositions in a plurality of magnetic layers, e.g. layer compositions having…
G11B 5/7369
Non-polymeric layer under the lowermost magnetic recording layer: two or more non-magnetic underlayers, e.g. seed layers or barrier layers
G11B 5/737
Two or more non-magnetic underlayers, e.g. seed layers or barrier layers: physical structure of underlayer, e.g. texture
G11B 5/7379
Non-polymeric layer under the lowermost magnetic recording layer: seed layer, e.g. at least one non-magnetic layer is specifically adapted as a…

Magnetic recording medium and magnetic recording device

Life of this patent

Magnetic recording medium and magnetic recording device

Life of this patent

Abstract

Claims20