GLASS COMPOSITIONS WITH IMPROVED CHEMICAL AND MECHANICAL DURABILITY Russian patent published in 2018 - IPC C03C3/87 

FIELD: glass.

SUBSTANCE: invention relates to chemically and mechanically resistant glass compositions and to glass articles made of them, and can be used to make a package for medicines. Glass composition include from about 74 to 80 mol. percent SiO₂; from 3 to 13 mol% of an alkaline earth oxide comprising MgO and CaO, X mol% Al₂O₃; and Y mol% alkaline oxide, and ratio of Y: X is greater than or equal to 1 and less than or equal to 2. Concentration of MgO in the glass composition is greater than the concentration of CaO, CaO is present in an amount of 0.1-1.0 mol% and the ratio (mol%) of CaO / (CaO + MgO) is less than or equal to 0.5. Alkali oxide includes Na₂O in an amount greater than or equal to 8 mol%. Glass composition does not contain boron or boron compounds. Glassware formed from the glass composition refers to at least class S3 acid resistance according to DIN 12116, at least to class A2 base resistance according to ISO 695 and a type HGA1 hydrolytic resistance according to ISO 720.

EFFECT: technical result of the invention is the creation of chemically resistant glasses that can be ion exchange strengthened.

13 cl, 7 dwg, 4 tbl