Magnetic recording medium, and thermal stability measuring method and apparatus of magnetic recording medium
US7420886B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 20, 2007 |
| Grant date | Sep 2, 2008 |
| Priority date | — |
| Expiry date | Apr 20, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/40
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
There is disclosed a magnetic recording medium in which a seed layer, under layer, intermediate layer, first magnetic layer, nonmagnetic layer, second magnetic layer, protective layer, and lubricant layer are successively laminated on a glass substrate, the nonmagnetic layer is constituted of an alloy containing Cr and C, and the magnetic layer is constituted of an alloy containing Co and Pt. The under layer includes at least the seed layer for finely dividing the crystal particles of the magnetic layer, the seed layer includes at least two or more layers of nonmagnetic films, and the intermediate layer formed of the material different from that of the nonmagnetic film is interposed between the nonmagnetic films. In measurement of the thermal stability of the magnetic recording medium, a head is used, the head includes a read/write element, and a write track width is twice or more as large as a read track width in the head.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.