Method for preparing perpendicularly magnetizable material usable on magnetic recording media
US5487878A · kind A · utility
Inventors
Key dates
| Filing date | Sep 1, 1994 |
| Grant date | Jan 30, 1996 |
| Priority date | — |
| Expiry date | Sep 1, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S428/90
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method for preparing a perpendicularly magnetizable material usable on magnetic recording media comprises the steps of: dissolving at least one member of the group consisting of strontium chloride and strontium nitrate with at least one member of the group consisting of iron chloride and iron nitrate in distilled water; adding citric acid to the resultant solution; controlling the pH of the solution to a range sufficient to completely dissociate the citric acid; heating the resultant solution with stirring to yield a gelatinous precursor; and subjecting the precursor to a temperature sufficiently high to remove the organic constituents thereof, which is characterized by controlling the pH of the solution to gelate the solution without the use of ethylene glycol, and can provide a perpendicularly magnetizable material superior in magnetic and particle properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.