Method of manufacturing a vitreous silica crucible having a transparent layer, bubble-containing layers, and a semi-transparent layer in its wall
US9719188B2 · kind B2 · utility
0Cited by
1References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 31, 2015 |
| Grant date | Aug 1, 2017 |
| Priority date | — |
| Expiry date | Aug 31, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T117/1032
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method of manufacturing of a vitreous silica crucible includes: fusing silica powder under a reduced pressure of −50 kPa or more and less than −95 kPa to form a transparent vitreous silica layer as an inner layer; fusing silica powder under a reduced pressure of 0 kPa or more and less than −10 kPa to form a bubble-containing vitreous silica layer as an intermediate layer; and fusing silica powder under a reduced pressure of −10 kPa or more and less than −50 kPa to form a semi-transparent vitreous silica layer as an outer layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.