Abstract The instant invention is directed to the production of essentially lead-free and cadmium-free frits which are eminently suitable for the production of decorative glazes and enamels to be used with glass, glass-ceramic, and ceramic articles. The frits exhibit good glass stability, demonstrate coefficient of thermal expansion (20°-300° C.) between about 52-65×10 -7 /°C., display excellent resistance to attack by acids and bases, and can be fired to fusion at temperatures between about 850°-1100° C. The compositions thereof consist essentially, expressed in weight percent on the oxide basis as calculated from the batch, of ______________________________________ SiO 2 51-60
B 2 O 3 4.5-8
BaO 0-13
SrO 0-18
BaO + SrO 6-30
ZrO 2 4-8
Al 2 O 3 5-8
Li 2 O 0-4
Na 2 O 0-5
K 2 O 0-5
Li 2 O + Na 2 O + K 2 O
1-5
MgO 0-6
CaO 0-12
Bi 2 O 3 0-10
MgO + CaO + Bi 2 O 3 0-20
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A frit essentially free from cadmium and lead demonstrating good glass stability, a coefficient of thermal expansion (20°-300° C.) between about 52-65×10 -7 /°C., a viscosity suitable for firing at about 850°-1100° C., and excellent resistance to attack by acids and bases as evidenced by no visual change in appearance and a weight loss of no more than about 0.05% after an exposure of 24 hours at 96° C. to a stirred aqueous solution containing 10% by weight citric acid and by no visual change in appearance and a weight loss of no more than 0.02% after an exposure of 24 hours at 96° C. to an aqueous solution containing 0.3% by weight alkaline detergent, said frit consisting essentially, expressed in weight percent on the oxide basis as calculated from the batch, of ______________________________________
SiO.sub.2 51-60
B.sub.2 O.sub.3 4.5-8
BaO 0-13
SrO 0-18
BaO + SrO 6-30
ZrO.sub.2 4-8
Al.sub.2 O.sub.3 5-8
Li.sub.2 O 0-4
Na.sub.2 O 0-5
K.sub.2 O 0-5
Li.sub.2 O + Na.sub.2 O + K.sub.2 O
1-5
MgO 0-6
CaO 0-12
Bi.sub.2 O.sub.3 0-10
MgO + CaO + Bi.sub.2 O.sub.3
0-20
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Claim 2
Dependent Claim
185 words
A frit essentially free from cadmium and lead demonstrating good glass stability, a coefficient of thermal expansion (20°-300° C.) between about 52-65×10 -7 /°C., a viscosity suitable for firing at about 850°-1100° C., and excellent resistance to attack by acids and bases as evidenced by no visual change in appearance and a weight loss of no more than about 0.05% after an exposure of 24 hours at 96° C. to a stirred aqueous solution containing 10% by weight citric acid and by no visual change in appearance and a weight loss of no more than 0.02% after an exposure of 24 hours at 96° C. to an aqueous solution containing 0.3% by weight alkaline detergent, said frit consisting essentially, expressed in weight percent on the oxide basis as calculated from the batch, of ______________________________________
SiO.sub.2 51-60
B.sub.2 O.sub.3 4.5-8
BaO 0-13
SrO 0-18
BaO + SrO 6-30
ZrO.sub.2 4-8
Al.sub.2 O.sub.3 5-8
Li.sub.2 O 0-4
Na.sub.2 O 0-5
K.sub.2 O 0-5
Li.sub.2 O + Na.sub.2 O + K.sub.2 O
1-5
MgO 0-6
CaO 0-12
Bi.sub.2 O.sub.3 0-10
MgO + CaO + Bi.sub.2 O.sub.3
0-20
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Claim 3
Dependent Claim
92 words
A frit according to claim 1 exhibiting a coefficient of thermal expansion ( 20°-300° C.) between about 52-60×10 -7 /°C. and a viscosity suitable for firing at about 850°-950° C. consisting essentially, expressed in weight percent on the oxide basis, as calculated from the batch, of ______________________________________
SiO.sub.2 56-60
B.sub.2 O.sub.3 4.5-6.5
BaO 0-13
SrO 0-16
BaO + SrO 6-16
ZrO.sub.2 4.5-7
Al.sub.2 O.sub.3 5-7
Li.sub.2 O 0-2
Na.sub.2 O 0-3
K.sub.2 O 0-2
Li.sub.2 O + Na.sub.2 O + K.sub.2 O
2-4.5
MgO 0-4
CaO 0-12
MgO + CaO 0-12
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