GLASS Russian patent published in 2008 - IPC C03C3/95 

FIELD: glass industry.

SUBSTANCE: invention relates to glass compositions used in making electric vacuum devices. Proposed glass comprises SiO₂, Al₂O₃, ZnO, Li₂O, Na₂O, K₂O, CaO, SrO, BaO, CeO₂, ZrO and, additionally, it comprises La₂O₃ and B₂O₃ in the following ratio of components, wt.-%: SiO₂, 45.0-50.0; Al₂O₃, 11.0-14.0; ZnO, 10.0-12.0; Li₂O, 0.5-1.0; Na₂O, 0.5-1.0; K₂O, 3.5-4.5; CaO, 1.0-2.0; SrO, 6.5-7.5; BaO, 3.0-4.5; CeO₂, 0.5-1.0; ZrO₂, 5.0-7.0; La₂O₃, 1.0-1.5, and B₂O₃, 3.0-3.5. Invention provides enhancing the softening point of glass.

EFFECT: improved and valuable property of glass.

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