GLASS FOR FIBER GLASS Russian patent published in 1995 - IPC

FIELD: glass industry. SUBSTANCE: glass has, wt.-% silicon oxide (SiO₂) 47.5-57.8; aluminium oxide (Al₂O₃) 17.1-19; titanium oxide (TiO₂) 1.2-2; ferric oxide (Fe₂O₃) 3.8-8.5; ferrous oxide (FeO) 3.4-7.0; manganese oxide (MnO) 0.11-0.19; calcium oxide (CaO) 6.5-10.8; magnesium oxide (MgO) 2.3-7.5; potassium oxide (K₂O) 0.8-2.5; sodium oxide (Na₂O) 2.2-4.6; sulfur oxide (SO₂) 0.01-0.20; phosphorus pentoxide (P₂O₅) 1.1-2.0; scandium oxide (Sc₂O₃) 0.03-1.2; zinc oxide (ZnO) 0.05-1.0. Ratio is Al₂O₃/(Ca+MgO)<2,0. Stability in 2N HCl (98 C, 3 h) is 98-98.9% in Ca(OH)₂ is 991.-99.8% Glass is used production of unbroken and rough fibers. EFFECT: enhanced quality of glass. 2 cl, 4 tbl