US4518564A
Expired / Lapsed
US
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Gallium and silver free, palladium based dental alloys for porcelain-fused-to-metal restorations
Assignee: Jeneric Industries Inc
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Filing: 1984-05-30
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Granted: 1985-05-21
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Expires: 2004-05-30
Abstract
Abstract A dental alloy for porcelain-fused-to-metal restorations is provided which consists essentially of, on a weight basis, about 60-90% palladium, an effective amount of ruthenium up to about 2% for the purpose of grain-refining the alloy, an effective amount of copper up to about 30% for the purpose of lowering the melting point and raising the thermal expansion, up to about 15% indium, up to about 16% tin, up to about 12% zinc, up to about 5% gold, and from about 0.05 to about 0.25% boron or calcium boride, the total of said constituents being 100%, wherein the sum of the copper, indium, tin and zinc concentrations is greater than about 18%, the sum of the indium, tin and zinc concentrations is greater than about 10%, and the sum of the indium and zinc concentrations is greater than about 5%, such that said alloy exhibits a melting point between about 1100° C. and 1400° C. and a coefficient of thermal expansion of about 0.66 to 0.72 at 500° C. To ensure essentially bubble-free restorations, the alloy is preferably made in a ceramic, rather than a carbon-containing, crucible and in a protective environment.
Inventors
- 👤 Arun Prasad
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:21
CPC Classifications
C; C22; C22C; C22C5/00; C22C5/04; A; A61; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/844
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
166 words
A dental alloy for porcelain-fused-to-metal restorations consisting essentially of, on a weight basis, about 60-90% palladium, an effective amount of ruthenium up to about 2% for the purpose of grain-refining the alloy, an effective amount of copper up to about 30% for the purpose of lowering the melting point and raising the thermal expansion, up to about 15% indium, up to about 16% tin, up to about 12% zinc, up to about 5% gold, and from about 0.05 to about 0.25% boron or calcium boride, the total of the named constituents being 100%, wherein the sum of the copper, indium, tin and zinc concentrations is greater than about 18%, the sum of the indium, tin and zinc concentrations is greater than about 10%, and the sum of the indium and zinc concentrations is greater than about 5%, such that said alloy exhibits a melting point between about 1100° C. and 1400° C. and a coefficient of thermal expansion of about 0.66 to 0.72 at 500° C.
Claim 2
Dependent Claim
166 words
A dental alloy for porcelain-fused-to-metal restorations consisting essentially of, on a weight basis, about 60-90% palladium, an effective amount of ruthenium up to about 2% for the purpose of grain-refining the alloy, an effective amount of copper up to about 30% for the purpose of lowering the melting point and raising the thermal expansion, up to about 15% indium, up to about 16% tin, up to about 12% zinc, up to about 5% gold, and from about 0.05 to about 0.25% boron or calcium boride, the total of the named constituents being 100%, wherein the sum of the copper, indium, tin and zinc concentrations is greater than about 18%, the sum of the indium, tin and zinc concentrations is greater than about 10%, and the sum of the indium and zinc concentrations is greater than about 5%, such that said alloy exhibits a melting point between about 1100° C. and 1400° C. and a coefficient of thermal expansion of about 0.66 to 0.72 at 500° C.
Claim 3
Dependent Claim
79 words
The alloy of claim 1 wherein the palladium concentration is between about 65 and 75%, the copper concentration is between about 8 and 16%, the indium concentration is between about 3.5 and 6%, the tin concentration is between about 2 and 6%, the ruthenium concentration is between about 0.5 and 1.0%, the zinc concentration is between about 2 and 5.5%, the gold concentration is between about 0.5 and 3.0%, and the boron concentration is between about 0.05 and 0.15%.
Claim 4
Dependent Claim
55 words
The alloy of claim 2 wherein the palladium concentration is about 70.625%, the copper concentration is about 14.5%, the indium concentration is about 4%, the tin concentration is about 4%, the ruthenium concentration is about 1.0%, the zinc concentration is about 3.75%, the gold concentration is about 2%, and the boron concentration is about 0.125%.
Claim 5
Dependent Claim
69 words
The alloy of claim 1 wherein the palladium concentration is between about 65 and 75%, the copper concentration is between about 8 and 16%, the indium concentration is between about 3.5 and 6%, the tin concentration is between about 2 and 6%, the ruthenium concentration is between about 0.5 and 1.0%, the zinc concentration is between 2 and 5.5%, and the boron concentration is between about 0.05 and 0.15%.
Claim 6
Dependent Claim
49 words
The alloy of claim 4 wherein the palladium concentration is about 72.625%, the copper concentration is about 14.5%, the indium concentration is about 4%, the tin concentration is about 4%, the ruthenium concentration is about 1.0%, the zinc concentration is about 3.75% and the boron concentration is about 0.125%.
Claim 7
Dependent Claim
20 words
The alloy of claim 1 wherein all or part of the boron is replaced by silicon, magnesium or mixtures thereof.
Claim 8
Dependent Claim
20 words
The alloy of claim 1 wherein all or part of the gold is replaced by platinum, iridium or mixtures thereof.
Claim 9
Dependent Claim
191 words
An essentially bubble-free, porcelain-fused-to-metal, dental restoration comprising porcelain fused to a metallic alloy consisting essentially of, on a weight basis, about 60-90% palladium, an effective amount of ruthenium up to about 2% for the purpose of grain-refining the alloy, an effective amount of copper up to about 30% for the purpose of lowering the melting point and raising the thermal expansion, up to about 15% indium, up to about 16% tin, up to about 12% zinc, up to about 5% gold, and from about 0.05 to about 0.25% boron or calcium boride, the total of the named constituents being 100%, wherein the sum of the copper, indium, tin and zinc concentrations is greater than about 18%, the sum of the indium, tin and zinc concentrations is greater than about 10%, and the sum of the indium and zinc concentrations is greater than about 5%, such that said alloy exhibits a melting point between about 1100° C. and 1400° C. and a coefficient of thermal expansion of about 0.66 to 0.72 at 500° C., and wherein the components of the alloy are combined in a ceramic crucible and in a protective environment.
Claim 10
Dependent Claim
191 words
An essentially bubble-free, porcelain-fused-to-metal, dental restoration comprising porcelain fused to a metallic alloy consisting essentially of, on a weight basis, about 60-90% palladium, an effective amount of ruthenium up to about 2% for the purpose of grain-refining the alloy, an effective amount of copper up to about 30% for the purpose of lowering the melting point and raising the thermal expansion, up to about 15% indium, up to about 16% tin, up to about 12% zinc, up to about 5% gold, and from about 0.05 to about 0.25% boron or calcium boride, the total of the named constituents being 100%, wherein the sum of the copper, indium, tin and zinc concentrations is greater than about 18%, the sum of the indium, tin and zinc concentrations is greater than about 10%, and the sum of the indium and zinc concentrations is greater than about 5%, such that said alloy exhibits a melting point between about 1100° C. and 1400° C. and a coefficient of thermal expansion of about 0.66 to 0.72 at 500° C., and wherein the components of the alloy are combined in a ceramic crucible and in a protective environment.
Claim 11
Dependent Claim
79 words
The restoration of claim 8 wherein the palladium concentration is between about 65 and 75%, the copper concentration is between about 8 and 16%, the indium concentration is between about 3.5 and 6%, the tin concentration is between about 2 and 6%, the ruthenium concentration is between about 0.5 and 1.0%, the zinc concentration is between about 2 and 5.5%, the gold concentration is between about 0.5 and 3.0%, and the boron concentration is between about 0.05 and 0.15%.
Claim 12
Dependent Claim
55 words
The restoration of claim 9 wherein the palladium concentration is about 70.625%, the copper concentration is about 14.5%, the indium concentration is about 4%, the tin concentration is about 4%, the ruthenium concentration is about 1.0%, the zinc concentration is about 3.75%, the gold concentration is about 2%, and the boron concentration is about 0.125%.
Claim 13
Dependent Claim
69 words
The restoration of claim 8 wherein the palladium concentration is between about 65 and 75%, the copper concentration is between about 8 and 16%, the indium concentration is between about 3.5 and 6%, the tin concentration is between about 2 and 6%, the ruthenium concentration is between about 0.5 and 1.0%, the zinc concentration is between 2 and 5.5%, and the boron concentration is between about 0.05 and 0.15%.
Claim 14
Dependent Claim
49 words
The restoration of claim 11 wherein the palladium concentration is about 72.625%, the copper concentration is about 14.5%, the indium concentration is about 4%, the tin concentration is about 4%, the ruthenium concentration is about 1.0%, the zinc concentration is about 3.75%, and the boron concentration is about 0.125%.
References Cited (Backward Citations)
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1988-05-20 | 1988-11-19 | 1989-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-20 | 1992-11-19 | 1993-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-20 | 1996-11-19 | 1997-05-21 | $7700.00 | Window Closed / Lapsed |