Method of producing decorations which are color-stable in a porcelain firing and a pigment composition suitable therefor

US5389402A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Dietrich Speer · Hanau, DE
• Akos Kiss · Alzenau, DE
• Jenny Horst · Gelnhausen, DE
• Guenter Halbritter · Rodenbach, DE
• Rita Loew · Rodgau, DE

Key dates

• Filing date: May 12, 1993
• Grant date: Feb 14, 1995
• Expiry date: May 12, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C8/14
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A method for producing decorations which are color-stable in a porcelain firing (glost firing), and a pigment composition suitable for this method, is disclosed. Inclusion pigments based on heavy-metal sulfides and selenides in an oxidic or silicate casing, especially ZrSiO.sub.4, result in more color-stable decorations in a porcelain firing if color-stabilizing auxiliary agents from the series of Zn compounds, especially ZnO or zinc-containing glass frits, or cerium(III) or cerium(IV) compounds, especially CeO.sub.2, are used in the decorative layer and/or glaze layer as color-stabilizing auxiliary agents. The amount used in the decorative layer is generally 5 to 50% by weight in the case of ZnO and CeO.sub.2, relative to the inclusion pigment. The pigment composition contains at least one of the color-stabilizing auxiliary agents in addition to an inclusion pigment.