US2853444A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrowinning of metals
Assignee: Dow Chemical Co
•
Filing: 1955-10-18
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Granted: 1958-09-23
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Expires: 1975-10-18
Abstract
No abstract record available.
Inventors
- 👤 David J Pye
- 👤 George F Schurz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:59
CPC Classifications
C; C25; C25C; C25C1/00; C25C1/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
40 words
A PROCESS FOR THE ELECTROWINNING OF ZINC WHICH COMPRISES ELECTROLYZING A ZINC SULFATE SOLUTION CONTAINING FROM ABOUT 25 TO ABOUT 150 PARTS BY WEIGHT OF A POLYETHYLENEIMINE PER MILLION PARTS BY WEIGHT OF SAID SOLUTION, SAID POLYETHYLENEIMINE HAVING THE FORMULA
Claim 2
Dependent Claim
40 words
A PROCESS FOR THE ELECTROWINNING OF ZINC WHICH COMPRISES ELECTROLYZING A ZINC SULFATE SOLUTION CONTAINING FROM ABOUT 25 TO ABOUT 150 PARTS BY WEIGHT OF A POLYETHYLENEIMINE PER MILLION PARTS BY WEIGHT OF SAID SOLUTION, SAID POLYETHYLENEIMINE HAVING THE FORMULA
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) | 1961-09-22 | 1962-03-24 | 1962-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-09-22 | 1966-03-24 | 1966-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-09-22 | 1970-03-24 | 1970-09-23 | $7700.00 | Window Closed / Lapsed |