Patent US2521908A successfully refreshed from Google Patents.
US2521908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
1-hydroxy-2-naphthamide colored couplers
Assignee: Eastman Kodak Co
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Filing: 1947-03-13
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Granted: 1950-09-12
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Expires: 1967-03-13
Abstract
No abstract record available.
Inventors
- 👤 Dudley B Glass
- 👤 Paul W Vittum
- 👤 Weissberger Arnold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:42
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/32; G03C7/333; G03C7/3335; C; C21; C21D; C21D9/00; C21D9/70
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
39 words
THE METHOD OF DEVELOPING A COLORED IMAGE IN A SILVER HALIDE EMULSION LAYER WHICH COMPRISES EXPOSING SAID EMULSION LAYER AND DEVELOPING IT WITH A PRIMARY AROMATIC AMINO DEVELOPING AGENT IN THE PRESENCE OF A COUPLER COMPOUND HAVING THE FORMULA:
Claim 2
Independent Claim
39 words
THE METHOD OF DEVELOPING A COLORED IMAGE IN A SILVER HALIDE EMULSION LAYER WHICH COMPRISES EXPOSING SAID EMULSION LAYER AND DEVELOPING IT WITH A PRIMARY AROMATIC AMINO DEVELOPING AGENT IN THE PRESENCE OF A COUPLER COMPOUND HAVING THE FORMULA:
References Cited (Backward Citations)
GB519208A
Cited
US2220123A
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US2310943A
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US2189817A
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US2313586A
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US2357394A
Cited
US2324832A
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US2455169A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-11 | 1954-03-13 | 1954-09-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-11 | 1958-03-13 | 1958-09-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-11 | 1962-03-13 | 1962-09-12 | $7700.00 | Window Closed / Lapsed |