Method for producing unsintered cristobalite particles
US5154905A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 26, 1991 |
| Grant date | Oct 13, 1992 |
| Priority date | — |
| Expiry date | Dec 26, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B19/1095
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for producing a nonsintered cristobalite particles comprising heating amorphous silica particles at a temperature of 1400.degree. to 1700.degree. C. in the presence of cristobalite particles (hereinafter referred to as cristobalite particles for addition and mixing) of at least 5 parts by weight based on 100 parts by weight of said amorphous silica particles to convert said amorphous silica particles to cristobalite particles with their particle form kept unchanged. According to the present invention, dense cristobalite having a low alkali content can be obtained in the form of particles. Such cristobalite is used as a filler, a dispersing agent, etc., and also as a material for high-quality artificial quartz, ceramics, etc., and particularly as a material for transparent quartz glass because of its generating no bubbles at the time of melt-molding.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.