Glass and method for producing the same, and member and apparatus using the same
AssigneeTosoh Corporation
InventorsMasahiro Ito, Kazuyoshi Arai
Life of this patent
Estimating the term…
Abstract
Methods for producing a glass that contains no bubbles with diameters of more than 0.1 mm and in which the occupied area fraction of bubbles with diameters of 0.1 mm or less is 0.05% or less, the methods including: placing raw material powders for at least one oxide of Si and a di- or higher-valent metal element in a container, mixing the raw material powders together and then melting the mixture by heating under reduced pressure to obtain a melt; pressurizing the melt in a He gas atmosphere, or heating the melt in an inert gas atmosphere other than a He gas atmosphere and then pressurizing the melt in the inert gas atmosphere; and cooling the melt.
Claims14
A method for producing a glass comprising at least one oxide of Si and a di-or higher-valent metal element, the method comprising the steps of:
- (1) placing raw material powders for the at least one oxide of Si and the di-or higher-valent metal element in a container, mixing the raw material powders together and then melting the mixture by heating under reduced pressure to obtain a melt;
- (2-2) heating the melt in an inert gas atmosphere which is at least one of a nitrogen gas atmosphere or an Ar gas atmosphere for 10 minutes or more and then pressurizing the melt in the inert gas atmosphere for 30 minutes or more;
- and
- (3) cooling the melt to obtain a glass containing no bubbles with diameters of more than 0.1 mm, wherein in the obtained glass:
- an occupied area fraction of bubbles with diameters of 0.1 mm or less is 0.05% or less, and
- the di-or higher-valent metal element contains at least one selected from the group consisting of Y, La, and Ce.
Dependencies are inferred from the claim text.