Borosilicate glass with high chemical resistance and use thereof

US6794323B2 · kind B2 · utility

Assignee

• Schott Glas · DE

Inventors

• Ulrich Peuchert · Bodenheim, DE
• Christian Kunert · Wiesbaden, DE
• Reiner Bartsch · Tirschenreuth, DE

Key dates

• Filing date: Aug 13, 2002
• Grant date: Sep 21, 2004
• Expiry date: Oct 22, 2022

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C4/20
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

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.