Refining Of Borosilicate Glasses Under Subatmospheric Pressures (Tables In English, Text In Japanese)

Glass refining technology has been investigated in some glasses which are difficult to refine. Glasses held under certain reduced pressures at relatively low temperatures showed severe foaming, followed by prominent reduction in the number of bubbles. One of the advantates of using the present technique is to suppress the bubble formation during subsequent stirring. In this article, it is shown that the subatmospheric treatment is not only useful for refining but also degassing procedures on borosilicate and aluminoborosilicate glass melts.