| 摘要 |
<p>A charged glass raw material B is melted in a melting tank 10 by heating with a burner 31 and by heating with electrodes 12, to form molten glass G. Then, the molten glass G flows into a tank additionally provided as a noble gas dissolving tank 20 through a throat 40. The noble gas dissolving tank 20 is provided with a noble gas dissolving device 53, and the noble gas dissolving device 53 is provided with sixteen noble gas inlets 22 for introducing a helium or neon gas supplied to a hearth through heat resistant gas introduction tubes 21 into the noble gas dissolving tank 20. Bubbles of a helium gas A having a purity of 99% are blown out from the noble gas inlets 22 in volumes such that the bubbles have an average diameter of 80 mm or less in the molten glass G.</p> |
