Increase in silicon content in the preparation of quartz glass
AssigneeHeraeus Quarzglas GmbH & Co. KG
InventorsNigel Robert Whippey, Marcus Constantin Göbel, Boris Gromann, Gerrit Scheich
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Abstract
A quartz glass body and a process for the preparation of a quartz glass body is disclosed. One process includes providing a silicon dioxide granulate from a pyrogenic silicon dioxide powder, making a glass melt out of the silicon dioxide granulate and making a quartz glass body out of at least part of the glass melt. In at least one process a silicon component different from silicon dioxide is added. A quartz glass body is obtainable by this process. A light guide, an illuminant and a formed body, are each obtainable by further processing of the quartz glass body.
Claims20
A process for the preparation of a quartz glass body comprising:
- providing a silicon dioxide granulate, wherein this provision comprises:
- providing a pyrogenic silicon dioxide powder;
- and
- processing the silicon dioxide powder to obtain a silicon dioxide granulate, wherein the silicon dioxide granulate has a greater particle diameter than the silicon dioxide powder, wherein the processing of the silicon dioxide powder comprises one of spray granulation, centrifugal pulverisation, fluidized bed granulation and roll granulation and wherein the BET surface area of the silicon dioxide granulate is in a range from 25-35 m2/g and wherein the silicon dioxide granulate has a particle size distribution D10 in the range from 50 to 150 μm and D50 in the range from 150 to 300 μm;
- continuously making a glass melt out of the silicon dioxide granulate in a continuous melting process;
- and
- making a quartz glass body out of at least part of the glass melt;
- wherein processing the silicon dioxide powder to obtain a silicon dioxide granulate includes adding elemental silicon in order to limit the OH content of the quartz glass body in the continuous melting process to less than 500 ppm.
Dependencies are inferred from the claim text.