Patent US4218244A successfully refreshed from Google Patents.
US4218244A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gold alloy for firing on porcelain for dental purposes
Assignee: Evonik Operations GmbH
•
Filing: 1978-11-01
•
Granted: 1980-08-19
•
Expires: 1998-11-01
Abstract
Abstract Gold alloys for firing on porcelain for dental purposes are prepared from 80 to 90% gold, 5 to 15% platinum, 0.5 to 10% palladium, 0.5 to 3% rhodium, 0.1 to 3% indium, 0 to 3% tin and optionally 0.1 to 2% tantalum and/or tungsten in place of or in addition to the rhodium.
Inventors
- 👤 Helmut Knosp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:29
CPC Classifications
C; C22; C22C; C22C5/00; C22C5/02; A; A61; A61K; A61K6/00; A61K6/80; A61K6/84; A61K6/844
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
74 words
A gold alloy having an intensive gold color and free from the gray-white coloration normally imparted to gold alloys containing palladium suitable for having porcelain fired thereon consisting of 80 to 90% gold, 5 to 15% platinum, 0.5 to 10% palladium, 0.1 to 3% indium, 0 to 3% tin and at least one member selected from the group consisting of 0.5 to 3% rhodium, 0.1 to 2% tantalum and 0.1 to 2% of tungsten.
Claim 2
Dependent Claim
74 words
A gold alloy having an intensive gold color and free from the gray-white coloration normally imparted to gold alloys containing palladium suitable for having porcelain fired thereon consisting of 80 to 90% gold, 5 to 15% platinum, 0.5 to 10% palladium, 0.1 to 3% indium, 0 to 3% tin and at least one member selected from the group consisting of 0.5 to 3% rhodium, 0.1 to 2% tantalum and 0.1 to 2% of tungsten.
Claim 3
Dependent Claim
10 words
A gold alloy according to claim 1 free from tin.
Claim 4
Dependent Claim
10 words
A gold alloy according to claim 1 free from rhodium.
Claim 5
Dependent Claim
15 words
A gold alloy according to claim 1 containing rhodium and tantalum and free from tungsten.
Claim 6
Dependent Claim
15 words
A gold alloy according to claim 1 containing rhodium and tungsten and free from tantalum.
Claim 7
Dependent Claim
13 words
A gold alloy according to claim 1 free from tin, rhodium and tungsten.
Claim 8
Dependent Claim
30 words
A gold alloy according to claim 1 consisting of 83 to 87% gold, 6 to 10% platinum, 3 to 6% palladium, 2 to 3% indium and 0.1 to 0.3% tantalum.
Claim 9
Dependent Claim
23 words
A gold alloy according to claim 7 consisting of about 84 to 85% gold, 8% platinum, 5% palladium, 2.5% indium and 0.1% tantalum.
Claim 10
Dependent Claim
20 words
A gold alloy according to claim 7 consisting of 85% gold, 2.5% indium, 4.4% palladium, 8.0% platinum and 0.1% tantalum.
References Cited (Backward Citations)
GB957493A
Cited
US3413723A
Cited
US3666540A
Cited
US3716356A
Cited
DE2424575A1
Cited
US4062676A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-08-19 | 1984-02-18 | 1984-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-08-19 | 1988-02-18 | 1988-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-08-19 | 1992-02-18 | 1992-08-19 | $7700.00 | Window Closed / Lapsed |