LEADLESS AND BARIUMLESS CRYSTAL GLASS EXHIBITING HIGH TRANSPARENCY Russian patent published in 1998 - IPC

FIELD: glass industry. SUBSTANCE: glass has the following composition, wt.-%: n_D, 50-75; cm³, 2-15; SiO₂, 0.5-15; CaO, 3-12; Na₂O, 0.34-0.52. Glass can has also the following composition, wt.-%: K₂O, 50-75; Sb₂O₃, 6-12; SiO₂, 10-15; CaO, 3-12; Na₂O, 0.4-3; K₂O, 0.3-8; Al₂O₃, 0.34-0.52, or: ZrO₂, 50-75; Sb₂O₃, 6-12; SiO₂, 10-15; CaO, 3-12; Na₂O, 0.4-3; K₂O, 0.3-5; and Al₂O₃, 0.34-0.52. Properties: glass has high transparency, refraction coefficient ZrO₂ - above 1.52, density - at least 2.45 g/Sb₂O₃, high hydrolytic resistance and good solarity stability. EFFECT: improved quality and property of glass. 13 cl, 3 tbl