Magnetic recording medium
US5908683A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 18, 1997 |
| Grant date | Jun 1, 1999 |
| Priority date | — |
| Expiry date | Apr 18, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/265
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording medium comprises a non-magnetic substrate, a lower coating layer, which is overlaid upon the non-magnetic substrate and primarily contains a binder and inorganic particles dispersed in the binder, and a magnetic layer, which is overlaid upon the lower coating layer and is constituted of at least a single layer. The magnetic layer contains at least a binder and ferromagnetic metal particles dispersed in the binder. The thickness of the magnetic layer falls within the range of 0.05 .mu.m to 0.5 .mu.m. The surface roughness of a top magnetic layer is at most 3 nm. The lower coating layer contains a fatty acid. An increase in the number of small protrusions, which have a height of at least 30 nm, does not occur substantially on the surface of the magnetic layer after the magnetic recording medium has been stored for seven days under environmental conditions of a temperature of 60.degree. C. and a relative humidity of 90%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.