US4073700A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing by electrodeposition bright deposits of gold and its alloys
Assignee: Individual
•
Filing: 1976-07-02
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Granted: 1978-02-14
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Expires: 1996-07-02
Abstract
Abstract This invention discloses a process for producing by electrodeposition bright deposits of gold and its alloys at greatly increased speeds and with an evenness of distribution significantly greater than conventional baths resulting in considerable savings in the average amount of gold deposited to meet a minimum thickness specification. The deposition of gold is promoted and enhanced by the presence of chelating agents characterized as carboxymethylated aminomethylene phosphonic acids and its salts.
Inventors
- 👤 Alfred M. Weisberg
- 👤 Harry Kroll
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:35
CPC Classifications
C; C25; C25D; C25D3/00; C25D3/02; C25D3/56; C25D3/62; C25D3/48
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
151 words
In a process for producing bright gold or gold-base alloy deposits, in a pH range between 3 and 8, from an aqueous solution containing a water soluble complex of gold cyanide, the improvement comprising carrying in solution in said solution a chelating agent selected from the group consisting of those represented by the formula: ##STR9## where m and n are either 1 or 2 and m + n = 3, and M is hydrogen or an alkali metal cation, and those represented by the formula: ##STR10## where n is 1, 2, or 3 and R may be either ##STR11## at least one R group being either a methylene carboxylic acid group or a methylenephosphonic acid group, and not all R's the same, and M is hydrogen or an alkali metal cation which process comprises electrolyzing said solution employing a metal object to be electroplated as a cathode in said electrolytic operation.
Claim 2
Dependent Claim
151 words
In a process for producing bright gold or gold-base alloy deposits, in a pH range between 3 and 8, from an aqueous solution containing a water soluble complex of gold cyanide, the improvement comprising carrying in solution in said solution a chelating agent selected from the group consisting of those represented by the formula: ##STR9## where m and n are either 1 or 2 and m + n = 3, and M is hydrogen or an alkali metal cation, and those represented by the formula: ##STR10## where n is 1, 2, or 3 and R may be either ##STR11## at least one R group being either a methylene carboxylic acid group or a methylenephosphonic acid group, and not all R's the same, and M is hydrogen or an alkali metal cation which process comprises electrolyzing said solution employing a metal object to be electroplated as a cathode in said electrolytic operation.
Claim 3
Dependent Claim
68 words
A process for producing bright gold or gold-base alloy deposits in a pH range between 3 and 8, from an aqueous solution containing a water soluble gold cyanide, an organic or inorganic acid and, as a component separate from said organic acid, 0.5 to 150 grams per liter of N-carboxymethyl imino di(methylenephosphonic acid) which comprises electrolyzing said solution employing a metal object to be electroplated as a cathode.
Claim 4
Dependent Claim
68 words
A process for producing bright gold or gold-base alloy deposits in a pH range between 3 and 8, from an aqueous solution containing a water soluble gold cyanide, an organic or inorganic acid and, as a component separate from said organic acid, 0.5 to 150 grams per liter of N-carboxymethyl imino di(methylenephosphonic acid) which comprises electrolyzing said solution employing a metal object to be electroplated as a cathode.
Claim 5
Dependent Claim
87 words
In a process for producing bright gold or gold-base alloy deposits in a pH range between 3 and 8 from an aqueous solution containing a water soluble gold cyanide, an organic acid to adjust pH and its ammonium or alkali metal salts, the improvement comprising adding to said solution as a component separate from said organic acid 0.5 to 150 grams per liter of N,N' -di(carboxymethyl) aminomethylene phosphonic acid and electrolyzing said solution employing a metal object to be electroplated as a cathode in such electrolytic operation.
Claim 6
Dependent Claim
87 words
In a process for producing bright gold or gold-base alloy deposits in a pH range between 3 and 8 from an aqueous solution containing a water soluble gold cyanide, an organic acid to adjust pH and its ammonium or alkali metal salts, the improvement comprising adding to said solution as a component separate from said organic acid 0.5 to 150 grams per liter of N,N' -di(carboxymethyl) aminomethylene phosphonic acid and electrolyzing said solution employing a metal object to be electroplated as a cathode in such electrolytic operation.
Claim 7
Dependent Claim
31 words
A process in accordance with claim 3 wherein the bath contains a nickel salt as a source of alloying nickel in the amount of 0.01 gram to 25 grams per liter.
Claim 8
Dependent Claim
31 words
A process in accordance with claim 3 wherein the bath contains a cobalt salt as a source of alloying cobalt in the amount of 0.01 gram to 25 grams per liter.
Claim 9
Dependent Claim
33 words
A process in accordance with claim 3 wherein the bath contains a nickel salt and a cobalt salt as alloying metals in the total amount of 0.1 gram to 25 grams per liter.
Claim 10
Dependent Claim
89 words
In a process for producing bright gold or gold-base alloy deposits in the pH range between 3 and 8 from an aqueous solution containing a water soluble gold cyanide, an organic acid to adjust pH and its ammonium or alkali metal salts the improvement comprising adding to said solution as a component separate from said organic acid 0.5 to 150 grams per liter of N,N'-di(carboxymethyl) 1,2 -ethylenediamine N,N' -di(methylene phosphonic acid) and electrolyzing said solution employing a metal object to be electroplated as a cathode in such electrolytic operation.
Claim 11
Dependent Claim
89 words
In a process for producing bright gold or gold-base alloy deposits in the pH range between 3 and 8 from an aqueous solution containing a water soluble gold cyanide, an organic acid to adjust pH and its ammonium or alkali metal salts the improvement comprising adding to said solution as a component separate from said organic acid 0.5 to 150 grams per liter of N,N'-di(carboxymethyl) 1,2 -ethylenediamine N,N' -di(methylene phosphonic acid) and electrolyzing said solution employing a metal object to be electroplated as a cathode in such electrolytic operation.
Claim 12
Dependent Claim
89 words
In a process for producing bright gold or gold-base alloy deposits in a pH range between 3 and 8, from an aqueous solution containing a water soluble gold cyanide, an organic acid to adjust pH and its ammonium or alkali metal salts the improvement comprising adding to said solution as a component separate from said organic acid 0.5 to 150 grams per liter of N,N' -di(carboxymethyl) 1,2 -ethylenediamine N,N' -di(methylenediphosphonic acid) and electrolyzing said solution employing a metal object to be electroplated as a cathode in such electrolytic operation.
Claim 13
Dependent Claim
89 words
In a process for producing bright gold or gold-base alloy deposits in a pH range between 3 and 8, from an aqueous solution containing a water soluble gold cyanide, an organic acid to adjust pH and its ammonium or alkali metal salts the improvement comprising adding to said solution as a component separate from said organic acid 0.5 to 150 grams per liter of N,N' -di(carboxymethyl) 1,2 -ethylenediamine N,N' -di(methylenediphosphonic acid) and electrolyzing said solution employing a metal object to be electroplated as a cathode in such electrolytic operation.
References Cited (Backward Citations)
US2673214A
Cited
US2961311A
Cited
US3293176A
Cited
US3394172A
Cited
US3617343A
Cited
US3672969A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-13 | 1981-08-15 | 1982-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-13 | 1985-08-15 | 1986-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-13 | 1989-08-15 | 1990-02-14 | $7700.00 | Window Closed / Lapsed |