Spherical corundum particles, process for preparation thereof and rubber or plastic composition having high thermal conductivity and having spherical corundum paticles incorporated therein
US5340781A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 29, 1992 |
| Grant date | Aug 23, 1994 |
| Priority date | — |
| Expiry date | Jul 29, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/44
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Disclosed are spherical corundum particles consisting essentially of single particles having an average particle size of 5 to 35 .mu.m and a shape not including cutting edges. The particles are prepared by adding one or more members selected from halogen compounds, boron compounds, and alumina hydrates to pulverized alumina having a specific particle size, heat-treating the mixture at a temperature of at least 1000.degree. C., and disintegrating the heat-treated product. A rubber or plastic composition having a high thermal conductivity is formed by incorporating such particles into a rubber or plastic, and this composition is valuable as a sealing material for a semiconductor, etc..
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.