US2739890A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photographic reproduction process
Assignee: Eastman Kodak Co
•
Filing: 1954-01-07
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Granted: 1956-03-27
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Expires: 1974-01-07
Abstract
No abstract record available.
Inventors
- 👤 Henry C Yutzy
- 👤 Edward C Yackel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:51
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/315
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
120 words
A METHOD OF PHOTOGRAPHIC REPRODUCTION WHICH COMPRIES EXPOSING TO A TWO-TONE SUBJECT A SUBSTANTIALLY UNHARDENED GELATINO-SILVER HALIDE EMULSION LAYER CONTAINING A GELATIN TANNING SILVER HALIDE DEVOLOPING AGENT, SAID EMULSION BEING NOT HARDER THAN A GELATIN LAYER CONTAINING 0.7 GRAM OF FORMALDEHYDE PER POUND OF GELATIN FRESHLY COATED, DEVELOPING THE EXPOSED EMULSION LAYER WITH AN ALKALINE SOLUTION TO OBTAIN A HARDENED GELATIN AND SILVER IMAGE IN THE REGION OF EXPOSURE AND SUBSTANTIALLY UNHARDENED GELATIN AND SILVER HALIDE IN THE UNEXPOSED REGION OF THE EMULSION LAYER, TREATING THE DEVELOPED EMULSION LAYER WITH A MEMBER OF THE CLASS CONSISTING OF AN ALKALINE SOLUTION OF FROM ABOUT 0.5 TO 5% OF A COMPOUND HAVING A SULFUR ATOM REACTING WITH SILVER HALIDE TO FORM SILVER
Claim 2
Independent Claim
120 words
A METHOD OF PHOTOGRAPHIC REPRODUCTION WHICH COMPRIES EXPOSING TO A TWO-TONE SUBJECT A SUBSTANTIALLY UNHARDENED GELATINO-SILVER HALIDE EMULSION LAYER CONTAINING A GELATIN TANNING SILVER HALIDE DEVOLOPING AGENT, SAID EMULSION BEING NOT HARDER THAN A GELATIN LAYER CONTAINING 0.7 GRAM OF FORMALDEHYDE PER POUND OF GELATIN FRESHLY COATED, DEVELOPING THE EXPOSED EMULSION LAYER WITH AN ALKALINE SOLUTION TO OBTAIN A HARDENED GELATIN AND SILVER IMAGE IN THE REGION OF EXPOSURE AND SUBSTANTIALLY UNHARDENED GELATIN AND SILVER HALIDE IN THE UNEXPOSED REGION OF THE EMULSION LAYER, TREATING THE DEVELOPED EMULSION LAYER WITH A MEMBER OF THE CLASS CONSISTING OF AN ALKALINE SOLUTION OF FROM ABOUT 0.5 TO 5% OF A COMPOUND HAVING A SULFUR ATOM REACTING WITH SILVER HALIDE TO FORM SILVER
References Cited (Backward Citations)
GB204101A
Cited
US2596756A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-03-27 | 1959-09-26 | 1960-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-03-27 | 1963-09-26 | 1964-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-03-27 | 1967-09-26 | 1968-03-27 | $7700.00 | Window Closed / Lapsed |