Patent ID: 6319867
Filing Date: 2001-11-20
Classification: C03C,C09K,Y10T

Abstract:
An aluminosilicate glass exhibiting a density less than about 2.45 g/cm.sup.3 and a liquidus viscosity greater than about 200,000 poises, the glass consisting essentially of the following composition as calculated in mol percent on an oxide basis: 65-75 SiO.sub.2, 7-13 Al.sub.2 O.sub.3, 5-15 B.sub.2 O.sub.3, 0-3 MgO, 5-15 CaO, 0-5 SrO, and essentially free of BaO, wherein:(a) the RO/Al.sub.2 O.sub.3 ratio is between 0.92 and 0.96, wherein R represents Mg, Ca, Sr and Ba; and(b) the glass has a linear coefficient of thermal expansion (CTE) over the temperature range 0-300.degree. C. between 28-33.times.10.sup.-7 /.degree. C.