US2944895A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Regeneration of photographic silver bleach solutions
Assignee: Eastman Kodak Co
•
Filing: 1955-04-13
•
Granted: 1960-07-12
•
Expires: 1975-04-13
Abstract
No abstract record available.
Inventors
- 👤 Lloyd E West
- 👤 Bernard A Hutchins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 23:51
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/395; G03C5/3952
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
84 words
THE PROCESSING OF DEVELOPED SILVER HALIDE PHOTOGRAPHIC EMULSION LAYERS WHICH COMPRISES TREATING SAID LAYERS WITH A BLEACH SOLUTION CONTAINING AN ALKALI METAL FERRICYANIDE AND AN ALKALI METAL BROMIDE, ADDING TO THE SPENT BLEACHING SOLUTION WHICH RESULTS A WATER-SOLUBLE PERSULFATE IN AN AMOUNT APPROXIMATELY CHEMICALLY EQUIVALENT TO THE FERROCYANIDE PRESENT IN THE SPENT LIQUOR PLUS SODIUM BROMIDE IN SUFFICIENT AMOUNT TO RESTORE THE BROMIDE CONTENT OF THE BLEACH SOLUTION AND BLEACHING FURTHER DEVELOPED SILVER HALIDE PHOTOGRAPHIC EMULSION LAYERS WITH THE REGENERATED BLEACH SOLUTION THUS OBTAINED.
Claim 2
Dependent Claim
84 words
THE PROCESSING OF DEVELOPED SILVER HALIDE PHOTOGRAPHIC EMULSION LAYERS WHICH COMPRISES TREATING SAID LAYERS WITH A BLEACH SOLUTION CONTAINING AN ALKALI METAL FERRICYANIDE AND AN ALKALI METAL BROMIDE, ADDING TO THE SPENT BLEACHING SOLUTION WHICH RESULTS A WATER-SOLUBLE PERSULFATE IN AN AMOUNT APPROXIMATELY CHEMICALLY EQUIVALENT TO THE FERROCYANIDE PRESENT IN THE SPENT LIQUOR PLUS SODIUM BROMIDE IN SUFFICIENT AMOUNT TO RESTORE THE BROMIDE CONTENT OF THE BLEACH SOLUTION AND BLEACHING FURTHER DEVELOPED SILVER HALIDE PHOTOGRAPHIC EMULSION LAYERS WITH THE REGENERATED BLEACH SOLUTION THUS OBTAINED.
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) | 1963-07-12 | 1964-01-11 | 1964-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-07-12 | 1968-01-11 | 1968-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-07-12 | 1972-01-11 | 1972-07-12 | $7700.00 | Window Closed / Lapsed |