Thermally tempered glass element and use thereof

US11021390B2 · kind B2 · utility

Assignee

• Schott AG · DE

Inventors

• Michael Schwall · Mainz, DE
• Christian Mix · Landshut, DE
• Jochen Alkemper · Klein-Winternheim, DE
• Peter Thomas · Singapore, SG

Key dates

• Filing date: Oct 25, 2019
• Grant date: Jun 1, 2021
• Expiry date: Oct 25, 2039

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C17/02
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A thermally tempered glass element is provided made of glass with two opposite faces that are under compressive stress of at least 40 MPa. The glass has a working point at which the glass has a viscosity of 104 dPa·s of at most 1350° C. The glass has a viscosity versus temperature profile and a coefficient of thermal expansion versus temperature profile of the glass are such that a variable (750° C.−T13)/(CTELiq−CTESol) has a value of at most 5*106 K2. The CTELiq is a coefficient of linear thermal expansion of the glass above a glass transition temperature Tg, the CTESol is a coefficient of linear thermal expansion of the glass in a temperature range from 20° C. to 300° C., and the T13 is a temperature at which the glass has a viscosity of 1013 dPa·s.