Patent ID: 7823416
Filing Date: 2010-11-02
Classification: C03B,C03C

Abstract:
1. A method of producing a glass article comprising the steps of: melting a glass raw material by heating; homogenizing the molten glass; forming the homogenized molten glass into a predetermined shape; cooling the shaped formed glass article to room temperature, wherein, in at least one of the step of melting a glass raw material by heating and the step of homogenizing the molten glass, a helium gas is brought into contact with the molten glass so that helium is dissolved in a glass article in such a manner that a volume ratio of an isotope of helium with a mass number of 3 to an isotope of helium with a mass number of 4 (0° C., 1 atm) is smaller than a volume ratio of the isotope of helium with a mass number of 3 to the isotope of helium with a mass number of 4 present in the atmosphere (0° C., 1 atm), wherein the molten glass is melted and homogenized while the molten glass is evaluated for degree of homogeneity by measuring a volume ratio of the isotope of helium with a mass number of 3 to the isotope of helium with a mass number of 4 in the molten glass, a formed glass article, or a glass article; and setting or changing a production condition for the glass article on the basis of the measured volume ratio.