FOAM GLASS AND PRODUCTION THEREOF

PURPOSE:To obtain lightweight foam glass having superior appearance, design, heat insulating property, fire resistance and durability and useful as interior and exterior building materials by laminating and integrating foamed glass layer and a crystallized glass layer. CONSTITUTION:A crystallized glass layer is formed on one side or both sides of a foamed glass layer in one body to produce form glass. The foamed glass layer is obtd. by adding a blowing agent such as calcium carbonate to soda lime glass and the coefft. of thermal expansion of the crystallized glass layer is 0.9-1.1 times as high as that of the foamed glass layer. The crystallized glass layer may be composed of 40% SiO2, 20% Al2O3, 7% B2O3, 5% MgO, 4% CaO, 4% ZnO, 10% Na2O3, 6% K2O, 2.5% TiO2 and 1.5% ZrO2.