Lead-free fine crystal glassware
AssigneeCorning Incorporated
InventorsGeorge B. Hares, Roger A. Miller, Lisa A. Tietz
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Abstract
This invention relates to fine glass crystal prepared from lead-free glass compositions. The glasses consist essentially, in weight percent, of ______________________________________ SiO.sub.2 54-64 BaO 8-13 Li.sub.2 O 0-3 SrO 8-13 Na.sub.2 O 0-6.5 ZnO 5.5-9 K.sub.2 O 0-7 BaO + SrO + ZnO 22-33 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 8-15 ______________________________________ wherein at least two of Li.sub.2 O, Na.sub.2 O, and K.sub.2 O are present and are present in essentially equimolar ratios.
Claims4
A glass essentially free from lead which exhibits a density of at least 2.75 grams/cm.sup.3, a bell-like tone when struck, a coefficient of thermal expansion ranging from 85.9-91.4.times.10.sup.-7 /.degree.C., and excellent resistance to weathering consisting essentially, expressed in terms of weight percent on the oxide basis, of
- ______________________________________ SiO.sub.2 54-64 BaO 8-13 Li.sub.2 O 0-3 SrO 8-13 Na.sub.2 O 0-6.5 ZnO 5.5-9 K.sub.2 O 0-7 BaO + SrO + ZnO 22-33 Li.sub.2 O + Na.sub.2 O + K.sub.2 O 8-15 ______________________________________
- wherein at least two of Li.sub.2 O, Na.sub.2 O and K.sub.2 O are present and are present in essentially equimolar ratios.
Dependencies are inferred from the claim text.