Process for ion exchange on glass or glass ceramic

US5127931A · kind A · utility

Assignee

• Schott Glaswerke · DE

Inventors

• Werner Kiefer · Ingelheim am Rhein, DE
• Erich Rodek · Mainz, DE

Key dates

• Filing date: Jul 1, 1991
• Grant date: Jul 7, 1992
• Expiry date: Jul 1, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C21/008
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

For ion exchange at the surface of glass or glass ceramic, the ion exchange is carried out by means of a solid layer containing mainly one or more salts which do not melt at the exchange temperature and contain mono- or divalent cations. The layer can be applied to the glass as a dispersion in water or as an organic dispersion medium. Preferably, its thickness is 0.02 to 2 mm and the salts have a particle size of less than 60 .mu.m. Despite the solid reaction, the ion exchange proceeds at a surprisingly rapid rate and leads to products having highly reproducible properties. Corrosive attack of the glass surface does not take place.