Transparent glass ceramic plate that has an opaque, colored bottom coating over the entire surface or over part of the surface

US7981823B2 · kind B2 · utility

Assignee

• Schott AG · DE

Inventors

• Friedrich Siebers · Nierstein, DE
• Ulrich Schiffner · Mainz, DE
• Wolfgang Schmidbauer · Mainz, DE
• Klaus Schönberger · Mainz, DE
• Petra Grewer · Wiesbaden, DE
• Erich Rodek · Mainz, DE

Key dates

• Filing date: Aug 13, 2009
• Grant date: Jul 19, 2011
• Expiry date: Aug 13, 2029

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C10/0054
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A transparent, colorless lithium-aluminosilicate glass ceramic plate with high-quartz mixed crystals as the prevailing crystal phase, which is provided on one side with an opaque, colored, temperature-stable coating over the entire surface or over the entire surface to a large extent, is described, which has a content of Nd2O3 of 40 to 4000 ppm, a Yellowness Index of less than 10% with a 4 mm glass (ceramic) layer thickness, and a variegation of colors of the glass or the glass ceramic in the CIELAB color system of C* of less than 5. The glass ceramic plate preferably has a composition (in % by weight based on oxide) of: Li2O 3.0-4.5, Na2O 0-1.5, K2O 0-1.5, ΣNa2O+K2O 0.2-2.0, MgO 0-2.0, CaO 0-1.5, SrO 0-1.5, BaO 0-2.5, ZnO 0-2.5, B2O3 0-1.0, Al2O3 19-25, SiO2 55-69, TiO2 1-3, ZrO2 1-2.5, SnO2 0-0.4, ΣSnO2+TiO2<3, P2O5 0-3.0, Nd2O3 0.01-0.4, CoO 0.0-0.004.