US4478691A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver plating procedure
Assignee: Nokia Bell Labs
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Filing: 1983-07-11
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Granted: 1984-10-23
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Expires: 2003-07-11
Abstract
Abstract A silver electroplating procedure is disclosed which permits rapid and efficient plating and yields ductile, adherent silver films. The electroplating bath comprises silver complexed with an aliphatic polyamine compound with 3 to 20 carbon atoms. Particularly useful are such polyamines as diaminopropane (particularly 1,3-diaminopropane), diethylenetriamine, 1,4-diaminobutane, 1,6-diaminohexane, etc. The procedure is also useful for electroplating a variety of silver alloys. In addition, the bath is highly stable, does not adversely affect the base material being plated and does not contain hazardous materials which require special disposal procedures.
Inventors
- 👤 Joseph A. Abys
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:04
CPC Classifications
C; C25; C25D; C25D3/00; C25D3/02; C25D3/56; C25D3/64; C25D3/46
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
176 words
A process for electroplating a metallic substance on a surface, said metallic substance consisting of at least 90 mole percent silver, comprising the step of passing current through a cathode, electroplating bath and anode with a cathode potential great enough to electroplate silver, said electrochemical bath having a conductivity greater than 10 -3 mho-cm and a pH greater than 7 characterized in that the electroplating bath is an aqueous solution comprising a. a source of silver, said source of silver consisting essentially of silver-aliphatic polyamine complex in which the aliphatic polyamine has from 3 to 20 carbon atoms and substituents are selected from the group consisting of hydrogen, hydroxide, chloride and bromide and said aqueous solution has a silver concentration between 0.01 molar and saturation and an aliphatic polyamine concentration of from 2 to 12 times the mole concentration of silver and b. a buffer, said buffer consisting essentially of the hydrogen phosphate/phosphate system with buffer concentration between 0.1 and 2 molar and with the ratio of hydrogen phosphate to phosphate ion from 5/1 to 1/5.
Claim 2
Dependent Claim
176 words
A process for electroplating a metallic substance on a surface, said metallic substance consisting of at least 90 mole percent silver, comprising the step of passing current through a cathode, electroplating bath and anode with a cathode potential great enough to electroplate silver, said electrochemical bath having a conductivity greater than 10 -3 mho-cm and a pH greater than 7 characterized in that the electroplating bath is an aqueous solution comprising a. a source of silver, said source of silver consisting essentially of silver-aliphatic polyamine complex in which the aliphatic polyamine has from 3 to 20 carbon atoms and substituents are selected from the group consisting of hydrogen, hydroxide, chloride and bromide and said aqueous solution has a silver concentration between 0.01 molar and saturation and an aliphatic polyamine concentration of from 2 to 12 times the mole concentration of silver and b. a buffer, said buffer consisting essentially of the hydrogen phosphate/phosphate system with buffer concentration between 0.1 and 2 molar and with the ratio of hydrogen phosphate to phosphate ion from 5/1 to 1/5.
Claim 3
Dependent Claim
11 words
The process of claim 1 in which the substituent is hydrogen.
Claim 4
Dependent Claim
20 words
The process of claim 2 in which the aliphatic polyamine is selected from the group consisting of 1,3-diaminopropane and diethylenetriamine.
Claim 5
Dependent Claim
14 words
The process of claim 3 in which the pH varies from 7.5 to 13.5.
Claim 6
Dependent Claim
14 words
The process of claim 4 in which the pH varies from 9.0 to 12.5.
Claim 7
Dependent Claim
23 words
The process of claim 1 in which the electroplating process is carried out at a temperature between room temperature and 80 degrees C.
Claim 8
Dependent Claim
16 words
The process of claim 6 in which the temperature is between 30 and 65 degrees C.
Claim 9
Dependent Claim
15 words
The process of claim 1 in which the silver is from 0.05 to 1.0 molar.
Claim 10
Dependent Claim
17 words
The process of claim 1 in which the plating current density is between 50 and 1000 ASF.
Claim 11
Dependent Claim
23 words
The process of claim 1 in which the silver in the electroplating bath is replenished by the addition of a source of silver.
Claim 12
Dependent Claim
14 words
The process of claim 10 in which the source of silver is silver oxide.
Claim 13
Dependent Claim
17 words
The process of claim 10 in which the source of silver is silver chloride or silver nitrate.
Claim 14
Dependent Claim
16 words
The process of claim 1 in which the plating current density is up to 50 ASF.
References Cited (Backward Citations)
US2355070A
Cited
US2666738A
Cited
US2660554A
Cited
US2735808A
Cited
US2777810A
Cited
US4088549A
Cited
US4265715A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-23 | 1988-04-23 | 1988-10-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-23 | 1992-04-23 | 1992-10-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-23 | 1996-04-23 | 1996-10-23 | $7700.00 | Window Closed / Lapsed |