Patent ID: 6826927
Filing Date: 2004-12-07
Classification: C03B,C03C,Y02P

Abstract:
A process for producing a high purity synthetic quartz powder, the process comprisingbaking a silica gel powder, made by a wet process, to form a synthetic quartz powder, where the baking is at atmospheric pressure and at a temperature in a range higher than a temperature at which hydroxyl groups are removed from the silica gel powder and lower than a temperature at which the silica gel powder sinters; and baking the synthetic quartz powder under a low pressure atmosphere simultaneously within a pressure range of from 0 Pa to less than 100 Pa and at a baking temperature, T, in a range of 600Â° C.the baking at atmospheric pressure is in dry air or an oxidizing atmosphere; the baking temperature during the baking at atmospheric pressure is in a range from more than 800Â° C. to less than 1400Â° C.; and the synthetic quartz powder is baked at atmospheric pressure for a baking me of 5 to 70 hours.