Process for producing synthetic quartz glass powder
AssigneeKimmon Manufacturing Co., Ltd. and Mitsubishi Chemical Corporation
InventorsHajime Onoda, Hiroshi Ota, Kazumi Kimura, Akira Utsunomiya, Masaru Shimoyama
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Abstract
Synthetic quartz glass powder is produced by (a) hydrolyzing an alkoxysilane to form a gel, (b) finely dividing the gel and then drying, or drying the gel and then finely dividing, and (c) calcining the obtained powder, the powder being maintained under an atmosphere with an oxygen concentration of not less than 30 vol % during at least a part of the calcining period at a temperature of not lower than 1,000.degree. C.
Claims5
A process for producing a synthetic quartz glass powder, which comprises the steps of:
- (a) hydrolyzing an alkoxysilane to form a gel thereof,
- (b) finely dividing the gel and then drying, or drying the gel and then finely dividing to form a powder, and
- (c) calcining the powder of step (b), the powder being maintained under an atmosphere with an oxygen concentration of not less than 30 vol % during at least a part of calcining at a temperature of not lower than 1,000.degree. C.
A process for reducing black contaminant in a synthetic quartz glass powder, which comprises calcining the synthetic quartz glass powder while maintaining it in an atmosphere with an oxygen concentration of not less than 30 vol % during at least a part of the calcining at a temperature of not lower than 1,000.degree. C.
Dependencies are inferred from the claim text.