The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 04, 2010
Filed:
May. 09, 2007
Stephan Ochs, Bad Camberg, DE;
Bodo Kuehn, Gelnhausen, DE;
Stephan Ochs, Bad Camberg, DE;
Bodo Kuehn, Gelnhausen, DE;
Heraeus Quarzglas GmbH & Co. KG, Hanau, DE;
Abstract
A known method for producing synthetic quartz glass with a predetermined hydroxyl group content comprises the following steps: a porous SiOsoot body is produced by flame hydrolysis or oxidation of a silicon-containing start compound and by layerwise deposition of SiOparticles on a rotating support; the soot body is subjected to a dehydration treatment in a reaction gas-containing drying atmosphere at a drying temperature for removing hydroxyl groups; and the SiOsoot body is vitrified into a body consisting of the synthetic quartz glass. Starting from this, and in order to permit a reproducible and reliable manufacture of synthetic, UV-radiation resistant quartz glass with predetermined hydroxyl group content and low chlorine content, it is suggested according to the invention that the dehydration treatment according to method step (b) comprises a drying phase during which ozone is used as the reaction gas, whereby the ozone content of the drying atmosphere is between 0.5% by vol. and 10% by vol. and the drying temperature is chosen in the range between 1200° C. and 1400° C., and whereby no halogens are supplied to the drying atmosphere.