US3702267A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrochemical cell containing a water-wettable polytetrafluoroethylene separator
Assignee: EIDP Inc
•
Filing: 1970-06-15
•
Granted: 1972-11-07
•
Expires: 1990-06-15
Abstract
Abstract POLYTETRAFLUOROETHYLENE IS PROVIDED CONTAINING FROM 20 TO 95% BY WEIGHT OF INORGANIC PARTICULATE SOLIDS WHICH ARE CHARACTERIZED BY A PARTICLE DIAMETER OF NO GREATER THAN 0.2 MICRON, BULK DENSITY NO GREATER THAN OF 0.25 GM./CM.3, AND A SPECIFIC SURFACE AREA OF AT LEAST 20 M.2/GM. THE PARTICULATE SOLIDS IMPART A HIGH DEGREE OF MICROPOROSITY AND WETTABILITY WHICH MAKES THE POLYMER USEFUL AS A FILTER OR AS AN ION PERMEABLE SEPARATOR IN ELECTROCHEMICAL CELLS.
Inventors
- 👤 Walter Gustav Grot
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:40
CPC Classifications
C; C08; C08K; C08K3/00; C08K3/18; C08K3/20; C08K3/22; H; H01; H01M; H01M50/00; H01M50/40; H01M50/409; H01M50/411; H01M50/414; H01M50/426; H01M50/431; H01M50/434; H01M50/443; H01M50/446; H01M50/489; H01M50/491; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10S; Y10S521/00; Y10S521/905
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1975-11-07 | 1976-05-08 | 1976-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-11-07 | 1980-05-08 | 1980-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-11-07 | 1984-05-08 | 1984-11-07 | $7700.00 | Window Closed / Lapsed |