US2865745A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Photographic reproduction process
Assignee: Eastman Kodak Co
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Filing: 1955-08-25
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Granted: 1958-12-23
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Expires: 1975-08-25
Abstract
No abstract record available.
Inventors
- 👤 Robert E Chan
- 👤 Herbert B Cowden
- 👤 William B Kendall
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:13
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/315
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
147 words
A METHOD OF PHOTOGRAPHIC REPRODUCTION WHICH COMPRISES EXPOSING TO A SUBJECT A SUBSTANTIALLY UNHARDENED GELATINO-SILVER HALIDE EMULSION LAYER CONTAINING A GELATIN TANNING SILVER HALIDE DEVELOPING AGENT, DEVELOPING THE EXPOSED EMULSION LAYER WITH AN ALKALINE SOLUTION TO OBTAIN A HARDENED GELATIN AND SILVER IMAGE IN THE REGION OF MOST EXPOSURE AND SUBSTANTIALLY UNHARDENED GELATIN AND SILVER HALIDE IN THE LESS EXPOSED REGIONS OF THE EMULSION LAYER, PRESSING THE DEVELOPED EMULSION LAYER WHILE MOIST WITH THE ALKALINE SOLUTION, AGAINST AN ABSORBENT SURFACE HAVING THEREON A MIXTURE OF THIOUREA AND SODIUM FORMALDEHYDE BISULFITE, THEREBY CAUSING ONLY THE UNEXPOSED REGIONS OF THE EMULSION LAYER TO ADHERE TO THE ABSORBENT SURFACE AND THE SILVER HALIDE THEREON TO BE CONVERTED TO A BLACK IMAGE, AND SEPARATING SAID RECEIVING SHEET AND EMULSION LAYER TO TRANSFER ONLY A STRATUM OF THE UNEXPOSED REGION OF THE EMULSION LAYER CONTAINING THE BLACK IMAGE TO THE RECEIVING SHEET.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-12-22 | 1962-06-23 | 1962-12-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-12-22 | 1966-06-23 | 1966-12-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-12-22 | 1970-06-23 | 1970-12-23 | $7700.00 | Window Closed / Lapsed |