GLASS FOR JEWELRY ENAMEL Russian patent published in 1997 - IPC

FIELD: production of JEWELRY enamels. SUBSTANCE: enamel comprises, mas. %: silicium dioxide with essential formula SiO₂, 43-48.5; boron oxide with essential formula B₂O₃, 6.5-8; lead oxide with essential formula PbO, 22-25; sodium oxide with essential formula Na₂O₃, 3.5-5.8; potassium oxide with essential formula K₂O, 9.8-11.4; aluminium oxide with essential formula Al₂O₃, 0.7-1.2; antimony oxide with essential formula Sb₂O₅, 0.05-5; fluorine, 1.9-2.4; cobalt oxide with essential formula CO₂O₃, 0.2-0.5; molybdenum oxide with essential formula MoO₃ 0.05-2.5. Temperature of synthesis is 1400 C, temperature of calcination of enamel is 780 C. Reflection coefficient of desired enamel is 65 %. EFFECT: improved quality of enamel. 2 tbl