US3637474A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrodeposition of palladium
Assignee: Sel Rex Corp
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Filing: 1968-08-26
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Granted: 1972-01-25
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Expires: 1988-08-26
Abstract
Abstract An electroplating bath for the deposition of palladium from a palladium-urea complex. A method for depositing palladium from a chemical solution containing a palladium-urea complex by passing an electric current through the solution, whereupon palladium deposits on the surface of a workpiece or a cathode.
Inventors
- 👤 Franco Zuntini
- 👤 Jean M Gioria
- 👤 Donald Gardner Foulke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:11
CPC Classifications
C; C25; C25D; C25D3/00; C25D3/02; C25D3/50; C25D3/52
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
17 words
The bath as claimed in claim 1 wherein the pH of the solution is 8.0 or greater.
Claim 2
Dependent Claim
34 words
The bath as claimed in claim 1 wherein a soluble sulfite compound is added in a quantity such that the sulfite concentration is between approximately 1.5 and approximately 70 grams per liter of solution.
Claim 3
Dependent Claim
26 words
The bath as claimed in claim 1 wherein a salt of ethylene diamine tetra-acetic acid is present in an amount sufficient to complex contaminating metal ions.
Claim 4
Independent Claim
56 words
A method of electrodepositing palladium on a workpiece which comprises passing an electric current through a chemical solution wherein the workpiece serves as a cathode, said chemical solution comprising an aqueous alkaline solution of a palladium-urea complex wherein the palladium content of the bath derived from said complex is at least about 2 grams per liter.
Claim 5
Dependent Claim
36 words
A method as claimed in claim 5 wherein the chemical solution contains a soluble sulfite compoUnd in a quantity such that the sulfite concentration is between approximately 1.5 and approximately 70 grams per liter of solution.
Claim 6
Dependent Claim
26 words
A method as claimed in claim 6 wherein a salt of ethylene diamine tetra-acetic acid is present in an amount sufficient to complex contaminating metal ions.
Claim 7
Dependent Claim
31 words
A method as claimed in claim 5 wherein the electric current passing through the solution is such that a current density of about 0.1 to about 1.2 amp. dm.2 is maintained.
Claim 8
Dependent Claim
21 words
A method as claimed in claim 5 wherein the temperature of the solution is maintained from about 40* to 60* C.
References Cited (Backward Citations)
US1981715A
Cited
US3290234A
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 |