Method for producing &agr;-alumina powder
US6524549B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1996 |
| Grant date | Feb 25, 2003 |
| Priority date | — |
| Expiry date | Feb 27, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/80
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Alpha alumina powder having a regulated particle size, a uniform particle shape and a narrow particle size distribution and further a low halogen content is produced by calcining at least one starting material selected from transition alumina and alumina compounds in a halogen-containing atmosphere which comprises a hydrogen halide gas, a halogen gas or a mixture of a halogen gas and steam and contains at least 0.1% by volume of at least one halogen-containing gas selected from the group consisting of hydrogen halide gas and halogen gas, and removing halogen from a calcined material. The produced alpha-alumina powder is excellent in a packing property and homogeneously packed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.