Patent US3869280A successfully refreshed from Google Patents.
US3869280A
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Process for gold precipitation
Assignee: EIDP Inc
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Filing: 1973-04-23
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Granted: 1975-03-04
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Expires: 1993-04-23
Abstract
Abstract An improved gold precipitation process is disclosed. In the reductive precipitation of gold from an aqueous solution of the chloride, agglomeration of the gold can be minimized by the use of small amounts of polyvinyl alcohol in the solution. The resultant fine, substantially nonagglomerated gold powder is useful to produce bright fired conductive patterns of gold on dielectric substrates, which gold does not bubble over a wide temperature range on being fired.
Inventors
- 👤 Darwin James Langlois
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:18
CPC Classifications
C; C22; C22B; C22B11/00; C22B11/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
71 words
IN A PROCESS FOR PREPARING FINELY DIVIDED GOLD POWDER BY REDUCTIVE PRECIPITATION OF GOLD FROM AN AQUEOUS SOLUTION OF GOLD CHLORIDE, THE IMPROVEMENT OF ADDING TO THE AQUEOUS SOLUTION OF AN AMOUNT OF POLYVINYL ALCOHOL EFFECTIVE TO REDUCE AGGLOMERATION OF THE GOLD PRECIPITATE, WHEREBY A SUBSTANTIALLY NONAGGLOMERATED FINE GOLD POWDER OR REDUCED BULK DENSITY IS PRODUCED, WHICH IS FIREABLE OVER A WIDE TEMPERATURE RANGE TO FILMS OF ENCHANCED BRIGHTNESS AND CONTINUITY.
Claim 2
Dependent Claim
71 words
IN A PROCESS FOR PREPARING FINELY DIVIDED GOLD POWDER BY REDUCTIVE PRECIPITATION OF GOLD FROM AN AQUEOUS SOLUTION OF GOLD CHLORIDE, THE IMPROVEMENT OF ADDING TO THE AQUEOUS SOLUTION OF AN AMOUNT OF POLYVINYL ALCOHOL EFFECTIVE TO REDUCE AGGLOMERATION OF THE GOLD PRECIPITATE, WHEREBY A SUBSTANTIALLY NONAGGLOMERATED FINE GOLD POWDER OR REDUCED BULK DENSITY IS PRODUCED, WHICH IS FIREABLE OVER A WIDE TEMPERATURE RANGE TO FILMS OF ENCHANCED BRIGHTNESS AND CONTINUITY.
Claim 3
Dependent Claim
18 words
A process according to claim 1 wherein the reducing agent is potassium sulfite, sodium sulfite, or mixtures thereof.
Claim 4
Dependent Claim
15 words
A process according to claim 1 wherein there is 0.1-10 grams PVA/liter of aqueous solution.
Claim 5
Dependent Claim
14 words
A process according to claim 3 wherein there is 0.3-3 grams PVA/liter aqueous solution.
References Cited (Backward Citations)
US2620714A
Cited
US3171734A
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US3505134A
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US3768994A
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US3816097A
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US3708313A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-03 | 1978-09-02 | 1979-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-03 | 1982-09-02 | 1983-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-03 | 1986-09-02 | 1987-03-04 | $7700.00 | Window Closed / Lapsed |