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US2448508A
Expired / Lapsed
US
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Photographic elements having a silver halide layer and an antihalation layer on a polyvinylpyridine layer
Assignee: EIDP Inc
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Filing: 1947-04-05
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Granted: 1948-09-07
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Expires: 1967-04-05
Abstract
No abstract record available.
Inventors
- 👤 Alles Francis Peter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:54
CPC Classifications
G; G03; G03C; G03C1/00; G03C1/76; G03C1/825; G03C1/835
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1939171A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-09-07 | 1952-03-08 | 1952-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-09-07 | 1956-03-08 | 1956-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-09-07 | 1960-03-08 | 1960-09-07 | $7700.00 | Window Closed / Lapsed |