US3669852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electroplating gold
Assignee: AT&T Inc
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Filing: 1969-10-23
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Granted: 1972-06-13
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Expires: 1989-10-23
Abstract
Abstract The removal of dissolved oxygen prior to and during plating from certain electroplating baths such as citrate and phosphate buffered gold cyanide plating baths, by introducing nitrogen gas or a chemical reducing agent such as hydrazine or sulfite ions into the bath, results both in increased plating efficiencies of up to 98 percent and decreased thickness variation of the plated deposit, over the normally encountered current density range.
Inventors
- 👤 Earl D Winters
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 20:31
CPC Classifications
C; C25; C25D; C25D3/00; C25D3/02; C25D3/48; C25D21/00; C25D21/04; C25D5/00; C25D5/003
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
26 words
The method of claim 1 in which the gas is introduced at the rate of 1 to 5 liters per minute per liter of the bath.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |