FLUORINE-CONTAINING STRONTIUM ALUMINOSILICATE GLASS FOR DENTAL GLASS IONOMER CEMENTS Russian patent published in 2023 - IPC C03C3/247 C03C6/06 A61K6/77 

FIELD: glass production.

SUBSTANCE: invention relates to powdered glass used in dentistry, in particular to fluorine-containing strontium aluminosilicate glass for dental glass ionomer cements. Fluorine-containing strontium aluminosilicate glass includes SiO₂, Al₂O₃, P₂O₅, SrO, AlF₃, SrF₂, besides, the following components are added to the original glass: Ga₂O₃, LaF₃, as well as salts of alkaline components K₂O, Na₂O, MgO, CaO are added, with the following ratios of components, wt.%: SiO₂ 21.0–28.0; Al₂O₃ 23.0–25.0; Ga₂O₃ 0–6.0; P₂O₅ 6.0–13.0; SrO 14.0–20.0; AlF₃ 11.0–12.0; SrF₂ 5.0–7.5; LaF₃ 0.2–5.0, up to 1 wt.% K₂O, Na₂O, MgO, CaO.

EFFECT: glass has a high transparency T≥80%, a refractive index close to the refractive index of the polymer matrix (n_dst = 1.51–1.54), and the value of TCLE α =52–64⋅^10-7 °C^-1 while maintaining the high manufacturability of the glass production process and reducing the melting temperature to temperatures below 1,500°C.

1 cl, 1 tbl, 4 ex