Borosilicate glass with high chemical resistance and use thereof
AssigneeSchott Glas
InventorsUlrich Peuchert, Christian Kunert, Reiner Bartsch
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Abstract
The borosilicate glass has a hydrolytic stability class of 1, an acid resistance class of 1 and a lye resistance class of at least 2 and a composition (in % by weight, based on oxide) of SiO2 70.5-76.5; B2O36.5-<11.5; Al2O3 4-8; Li2O 0.5-2; Na2O 4.5-9; K2O 0-5; with Li2O+Na2O+K2O 5.5-10.5; MgO 0-1; CaO 0-2; and CeO2 0-1, and optionally refining agents. This borosilicate glass is preferably free of As2O3, Sb2O3 and BaO and is then especially advantageous as a pharmaceutical packaging material. It also may contain up to 3% by weight TiO2 to block UV radiation. The borosilicate glass may include up to 0.5% by weight ZrO2 to reach a lye resistance class of 1.
Claims19
A borosilicate glass of high chemicals resistance, characterized by a composition comprising, in percent by weight based on oxide content:
- SiO2 70-77 B2O3 6-<11.5 Al2O3 4-8.5 Li2O 0.15-2 Na2O 4.5-9.5 K2O 0-5 with Li2O + Na2O + K2O 5-11 MgO 0-2 CaO 0-2.5 with MgO + CaO 0-3 ZrO2 0-<0.5 CeO2 0-1,
- and optionally at least one standard refining agent in an amount sufficient for refining.
A borosilicate glass at high chemicals resistance, characterized by a composition comprising, in percent by weight based on oxide content:
- SiO2 70.5-76.5 B2O3 6.5-<11.5 Al2O3 4-8 Li2O 0.7-1.5 Na2O 4.5-9 K2O 0-5 with Li2O + Na2O + K2O 5.5-10.5 MgO 0-1 CaO 0-2 with MgO + CaO 0-3 ZrO2 0-<0.5 CeO2 0-1,
- and optionally at least one standard refining agent in an amount sufficient for refining.
A packaging material for pharmaceuticals, said packaging material consisting of a borosilicate glass having a coefficient of thermal expansion (α20/300) equal to 5×10−6/K to 6.0×10−6/K and a working point (VA) of at most 1180° C., an acid resistance class (S) of 1, a Lye resistance class (L) of at least 2 and a hydrolytic stability (H) of 1 and characterized by a composition comprising, in percent by weight based on oxide content:
- SiO2 70.5-76.5 B2O3 6.5-<11.5 Al2O3 4-8 Li2O 0.7-1.5 Na2O 4.5-9 K2O 0-5 with Li2O + Na2O + K2O 5.5-10.5 MgO 0-1 CaO 0-2 with MgO + CaO 0-3 ZrO2 0-<0.5 CeO2 0-1,
- and optionally at least one standard refining agent in an amount sufficient for refining, but with the proviso that the boroslilcate glass is free of free of As2O3 and Sb2O3 apart from inevitable impurities and free of BaO.
Dependencies are inferred from the claim text.