Low-melting, lead-free ceramic frits

Abstract

A lead-free low-melting frit is made by combining raw materials in amounts such that the product will have a specific oxide analysis, melting the raw materials at a temperature greater than 1000.degree. C. and cooling the thus-formed fused glass in a manner such that a frit is formed. The low-melting frit has the following oxide analysis: 7-12.5 parts by weight alkali oxide selected from 2-9 parts by weight Na.sub.2 O and 2-7 parts by weight Li.sub.2 O; 23-34 parts by weight B.sub.2 O.sub.3 ; 2-4 parts by weight Al.sub.2 O.sub.3 ; 30-45 parts by weight SiO.sub.2 ; 0.75-4 parts by weight F; 2-4 parts by weight P.sub.2 O.sub.5 ; 4-8 parts by weight ZnO; and 2-5 parts by weight TiO.sub.2. These frits are durable, have an incipient fusion point less than about 450.degree. C. and a coefficient of thermal expansion less than 10.times.10.sup.-6 cm/cm/.degree.C. The frits of the present invention are particularly useful as components in vitrifiable glass decorating colors.

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