Composite glass articles spontaneous opal glass and enamel of Li.sub.2 -O-B.sub.2 -O.sub.3 -TiO.sub.2 -ZrO.sub.2 -PbO-SiO.sub.2

US4038448A · kind A · utility

Assignee

• Corning Glass Works · US

Inventors

• David C. Boyd · Somerville, US
• Francis A. Cantaloupe · Horseheads, US
• William H. Dumbaugh, Jr. · Corning, US
• James E. Flannery · Corning, US
• Louis M. Holleran · Elmira, US
• Sylvester R. Sandor · Corning, US
• Dale R. Wexell · Corning, US

Key dates

• Filing date: Jun 4, 1976
• Grant date: Jul 26, 1977
• Expiry date: Jun 4, 1996

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/24942
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

This invention relates to the production of a composite article consisting of an opal glass body exhibiting a dense, milky-white appearance coated with an adherent enamel demonstrating high gloss and exceptional chemical durability. More specifically, the opal glasses of the present invention have compositions within the Na.sub.2 O-Al.sub.2 O.sub.3 -SiO.sub.2 -F system and demonstrate a softening point in excess of 760.degree. C., a strain point in excess of 490.degree. C., and a coefficient of thermal expansion (0.degree.-300.degree. C.) of about 66-75 .times. 10.sup..sup.-7 /.degree. C. The enamels of the instant invention have flux compositions within the Li.sub.2 O-B.sub.2 O.sub.3 -TiO.sub.2 -ZrO.sub.2 -PbO-SiO.sub.2 system, will fire to a high gloss in less than about 10 minutes at temperatures below about 720.degree. C., will exhibit coefficients of thermal expansion (25.degree.-300.degree. C.) about 3-10 points lower than the opal glass substrate, will demonstrate lead release after chemical attack of less than about 2 .mu.g/cm.sup.2, and will manifest excellent resistance to dishwasher detergents.