US3630863A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cell diaphragm treatment
Assignee: PPG Industries Inc
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Filing: 1968-11-13
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Granted: 1971-12-28
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Expires: 1988-11-13
Abstract
Abstract THE EFFECTIVE LIFE OF ELECTROLYTIC CELL DIAPHRAGMS IS EXTENDED BY TREATMENT WITH HYDROXY CARBOXYLIC COMPOUNDS, E.G., HYDROXY CARBOXYLIC ACIDS SUCH AS GLUCONIC ACID OR SALTS. THIS TREATMENT REMOVES SUBSTANCES WHICH ARE KNOWN TO RESTRICT DIAPHRAGM POROSITY.
Inventors
- 👤 Thomas C Jeffery
- 👤 Waylon L White
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 19:29
CPC Classifications
C; C25; C25B; C25B1/00; C25B1/01; C25B1/34; C25B1/46; C25B15/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-12-27 | 1975-06-28 | 1975-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-27 | 1979-06-28 | 1979-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-27 | 1983-06-28 | 1983-12-28 | $7700.00 | Window Closed / Lapsed |