Patent US3779958A successfully refreshed from Google Patents.
US3779958A
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Method of preparing a phenol formal-dehyde amine microporous sheet
Assignee: WR Grace and Co
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Filing: 1971-07-15
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Granted: 1973-12-18
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Expires: 1991-07-15
Abstract
Abstract MICROPOROUS RESINOUS SHEETS PARTICULARLY USEFUL AS BATTERY SEPARATORS ARE PREPARED FROM PHENOL/FORMALDEHYDE/ AMINE RESINOUS PRE-PRODUCTS.
Inventors
- 👤 K Ohba
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:42
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/28; B; B29; B29C; B29C67/00; B29C67/20; B29C67/202; H; H01; H01M; H01M50/00; H01M50/40; H01M50/409; H01M50/411; H01M50/414; C08J2361/00; C08J2361/34; Y; Y02; Y02E; Y02E60/00; Y02E60/10
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) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |