GLAZE Russian patent published in 2008 - IPC C03C8/12 

FIELD: chemistry.

SUBSTANCE: invention pertains to the technology of silicates and relates to fritted glaze for coating porcelain, faience and majolica objects. The glaze contains SiO₂, Al₂O₃, CaO, MgO, Na₂O, K₂O, B₂O₃, ZnO, CuO, ZrO₂ and P₂O₅, with the following ratios of components, in the given mass ratios: SiO₂ - 50.0-53.0; Al₂O₃ - 5.0-7.0; CaO - 2.0-3.0; MgO - 4.0-6.0; Na₂O - 1.0-2.0; K₂O - 2.0-4.0; B₂O₃ - 17.5-22.5; ZnO - 4.0-6.0; CuO - 0.5-1.0; ZrO₂ - 3.0-5.0; P₂O₅ - 0.5-1.0.

EFFECT: increased thermal resistance and lowering of the thermal coefficient of expansion of the glaze.

1 tbl