Magnetic recording medium comprising a glass substrate of controlled surface roughness and a magnetic thin film layer of gamma Fe.sub.2 O.sub.3
US5094898A · kind A · utility
18Cited by
4References
15Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 21, 1990 |
| Grant date | Mar 10, 1992 |
| Priority date | — |
| Expiry date | Jun 21, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording disk comprising a rigid substrate and a magnetic layer of the continuous thin film type predominantly composed of .gamma.-Fe.sub.2 O.sub.3 shows high durability, especially CSS durability when the magnetic layer has specific peak area ratios in an X-ray diffraction chart thereof, the surface roughness of the substrate and medium surface is controlled to desired ranges, and a lubricating film of a perfluoro derivative of poly(n-propylene oxide) with a specific molecular weight is used. Reliable recording/reproduction can be conducted on the magnetic recording disk using a flying magnetic head.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.