GREEN GLASS ABSORBING INFRARED AND ULTRAVIOLET RADIATION Russian patent published in 1997 - IPC

FIELD: glass industry. SUBSTANCE: product: sodium-calcium-silicate green glass. Glass is obtained by iron reduction (as Fe₂O₃) to FeO under control of relative content of these two iron oxides without use of CeO₂ and other ultraviolet-absorbing additions. Green glass has, wt.-%: silicon oxide (SiO₂), 71-74; calcium oxide (CaO), 8-10; magnesium oxide (MgO), 3-5; sodium oxide (Na₂O), 12-20; aluminium oxide (Al₂O₃), 0.1-0.3; ferrous oxide (FeO), 0.2-0.24; sulfur oxide (SO₃), 0.2-0.25; iron oxides FeO + Fe₂O₃, 0.7-0.95. Percent of the reduced FeO of total iron oxides level is 25-29% and ratio FeO/FeO + Fe₂O₃ = 0.24-0.27. Green glass can contain up to 0.1 wt.-% K₂O. EFFECT: improved quality and property of glass. 4 cl, 1 tbl