US3637473A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for electroplating gold
Assignee: Engelhard Minerals and Chemicals Corp
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Filing: 1969-07-03
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Granted: 1972-01-25
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Expires: 1989-07-03
Abstract
Abstract In an improved gold plating process the alkali metal concentration in the bath is maintained substantially constant during the plating operation by contacting the plating bath with an ammoniated cation exchange resin to replace alkali metal ions with ammonium ions and operating the ion exchanged plating bath at 60*-90* C. This process is particularly applicable when heavy coatings are desired, for example, in electroforming processes.
Inventors
- 👤 Lawrence Greenspan
- 👤 Heinrich K Straschil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 17:19
CPC Classifications
C; C25; C25D; C25D21/00; C25D21/16; C25D21/22; B; B01; B01J; B01J39/00; B01J39/04; B01J39/05
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
18 words
A process of electroplating gold according to claim 1 wherein the pH is maintained at 5.5 to 7.5.
Claim 2
Dependent Claim
28 words
A process of electroplating gold according to claim 2 wherein the process is continuously operated to form a gold coating of about 3 to 100 mils in thickness.
Claim 3
Dependent Claim
23 words
A process of electroplating old according to claim 3 wherein the Baume of the plating bath is maintained within + or - 2*.
Claim 4
Dependent Claim
15 words
A process of claim 1 wherein the gold-replenishing salt is an alkali metal gold cyanide.
Claim 5
Dependent Claim
13 words
A process of claim 5 wherein the alkali metal gold cyanide is KAu(CN)2.
Claim 6
Dependent Claim
13 words
A process of claim 5 wherein the alkali metal gold cyanide is NaAu(CN)2.
Claim 7
Dependent Claim
30 words
A process of electroplating gold according to claim 1 wherein the cation exchange resin is an ammoniated form of a highly sulfonated divinylbenzenepolystyrene copolymer or a highly sulfonated polystyrene polymer.
Claim 8
Dependent Claim
27 words
A process of electroplating gold according to claim 1 wherein the ammoniated cation exchange resin is regenerated after about 70 percent of the exchange capacity is used.
Claim 9
Dependent Claim
19 words
A process of electroplating gold according to claim 1 wherein the bath is maintained at 65* to 75* C.
References Cited (Backward Citations)
GB1051383A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-24 | 1975-07-26 | 1976-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-24 | 1979-07-26 | 1980-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-24 | 1983-07-26 | 1984-01-25 | $7700.00 | Window Closed / Lapsed |