Magnetic recording medium
US5906884A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 15, 1995 |
| Grant date | May 25, 1999 |
| Priority date | — |
| Expiry date | Aug 15, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S428/90
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording medium has a substrate made of a nonmetal nonmagnetic material whose coefficient of linear expansion lies within a range from 0.000013/deg to 0.0001/deg. A magnetic layer is formed on the substrate as a thin polycrystalline film or a thin amorphous film. The magnetic layer has Co as a main component, which exhibits a negative magnetostrictive constant so that its coercive force rises in the direction of compressive strain. The magnetic layer is subjected to an in-plane compressive strain from the substrate due to a difference between the coefficient of thermal expansion of the substrate and the magnetic layer so that high coercivity is obtained in the magnetic layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.