FLOAT GLASS FOR DISPLAY SUBSTRATE AND PROCESS FOR PRODUCING THE SAME

摘要

A float glass for display substrate that without losing of the performance as a substrate glass for display, attains lowering of high-temperature viscosity. There is provided a float glass for display substrate characterized by having a composition composed substantially of, by mass% on an oxide basis, 52 to 62% SiO<SUB>2</SUB>, 5 to 15% Al<SUB>2</SUB>O<SUB>3</SUB>, over 0 to 9% MgO, 3 to 12% CaO, 9 to 18% SrO, 0 to 13% BaO, 25 to 30% MgO+CaO+SrO+BaO, 6 to 14% Na<SUB>2</SUB>O+K<SUB>2</SUB>O+Li<SUB>2</SUB>O, 0 to 6% ZrO<SUB>2</SUB> and 0 to 1% SO<SUB>3</SUB>, and characterized in that the temperature of glass melt corresponding to a viscosity of 10<SUP>2</SUP> dPas is 1520°C or below, the temperature of glass melt corresponding to a viscosity of 10<SUP>4</SUP> dPas is 1120°C or below, the glass transition temperature is 610°C or above and the specific gravity is 2.9 or below.