Magnetic powder for magnetic recording and magnetic recording medium containing the same
US5494749A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 16, 1994 |
| Grant date | Feb 27, 1996 |
| Priority date | — |
| Expiry date | Sep 16, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2982
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic powder for magnetic recording is disclosed which comprises composite magnetic particles (A), each of which contains hexagonal ferrite and spinel structure ferrite, and single phase magnetic particles of hexagonal ferrite (B). When the mixing ratio [(A):(B)] of (A) and (B) in the range from 5:95 to 95:5, remarkable effect can be obtained. Especially, when the mixing ratio of (A) and (B) is in the range from 5:95 to 30:70, the dispersion property is improved due to disturbance of magnetic stacking. Thus, the magnetic powder in this mixing ratio is particularly suitable for magnetic recording in a short wavelength range. When the mixing ratio of (A) and (B) is in the range from 70:30 to 95:5, the reproduction output is improved due to activation of (A). Thus, the magnetic powder in this mixing ratio is specifically suitable for magnetic recording in a long wavelength range. By containing the magnetic powder described above, a perpendicular magnetic recording medium with high electromagnetic characteristics, particularly a high S/N ratio and a low noise can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.