SMELTING OF PHOSPHATE GLASS

摘要

PURPOSE:To obtain colorless and transparent glass having a high light transmittance, by bubbling a gas into phosphate glass in a molten state to stir the glass. CONSTITUTION:An alumina pipe is inserted into phosphate glass converted into a molten state. A gas is blown thereinto to stir the glass by bubbling and the glass is then annealed. N2, O2, Ar, He and a blend thereof are used as the gas and the flow rate thereof is preferably about 10ml/min based on 100g glass at the glass melting temperature. The bubbling with the gas in place of stirring with a conventional platinum stirring rod is carried out in this method. Sufficient stirring effect can be obtained and clouding of glass can be prevented.