Composition for texturing magnetic disk
US5609657A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 22, 1996 |
| Grant date | Mar 11, 1997 |
| Priority date | — |
| Expiry date | Feb 22, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/8404
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The composition for texturing a magnetic disk contains 0.1-5 weight %, based on the composition, of polycrystalline sintered alumina abrasives in a grinding fluid, the abrasives being produced by a sol-gel method comprising the steps of mixing a slurry of alumina hydrate with a dilute acid for solation, mixing the resultant alumina hydrate sol with a seed and/or a modifier, drying said alumina hydrate sol at 50.degree.-120.degree. C. for gelation, pulverizing and classifying the resultant gel, calcinating said gel at 400.degree.-900.degree. C., sintering the calcinated alumina particles at 1100.degree.-1400.degree. C., and pulverizing and classifying the resultant sintered alumina particles to a maximum particle size of 5 .mu.m or less and an average particle size of 0.1-3 .mu.m.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.