Patent US2687447A successfully refreshed from Google Patents.
US2687447A
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Battery separator
Assignee: Dewey and Almy Chemical Co
•
Filing: 1951-04-25
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Granted: 1954-08-24
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Expires: 1971-04-25
Abstract
No abstract record available.
Inventors
- 👤 Merrill Edward Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:42
CPC Classifications
D; D21; D21H; D21H11/00; D21H11/16; D21H11/20; D21J; D21J1/00; D21J1/08; H; H01; H01B; H01B3/00; H01B3/18; H01B3/185; H01M; H01M50/00; H01M50/40; H01M50/409; H01M50/411; H01M50/429; H01M50/4295; H01M50/44; Y; Y02; Y02E; Y02E60/00; Y02E60/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US2175154A
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US2105711A
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US2084272A
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US2382621A
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US2591754A
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US2520963A
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US2645577A
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US2566960A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-08-23 | 1958-02-22 | 1958-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-08-23 | 1962-02-22 | 1962-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-08-23 | 1966-02-22 | 1966-08-24 | $7700.00 | Window Closed / Lapsed |