US3762922A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silver halide photographic images
Assignee: EIDP Inc
•
Filing: 1971-03-31
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Granted: 1973-10-02
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Expires: 1991-03-31
Abstract
Abstract The image quality of photographic pictures containing, in addition to a silver image, a dye image resulting from developer, is improved by treatment with an alkaline solution containing a heavy metal complex.
Inventors
- 👤 L Lugosy
- 👤 M Grossa
- 👤 W Pistor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 18:14
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/40; G03C7/00; G03C7/30; G03C7/3046
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
29 words
A process according to claim 1 wherein said heavy metal complex is formed from a metal selected from the group consisting of copper, cobalt, nickel, cadmium, zinc and silver.
Claim 2
Dependent Claim
15 words
A process according to claim 2 wherein said developer is a compound having the formula:
Claim 3
Dependent Claim
9 words
A process according to claim 3, said developer being:
Claim 4
Dependent Claim
9 words
A process according to claim 3, said developer being:
Claim 5
Dependent Claim
31 words
A process according to claim 3, wherein the complex former of said heavy metal complex is selected from the group consisting of ammonia, soluble amines, hydroxycarboxylic acids and soluble mercapto compounds.
Claim 6
Dependent Claim
13 words
A process according to claim 1, said alkaline solution containing a fixing agent.
Claim 7
Dependent Claim
13 words
A process according to claim 7, said complex former being a mercapto compound.
Claim 8
Dependent Claim
22 words
A process according to claim 8, said mercapto compound being selected from the group consisting of thioglycerol, thioglycol, thioglycollic acid and cysteine.
Claim 9
Dependent Claim
20 words
A process according to claim 3, wherein said heavy metal complex is formed from copper sulfate and potassium sodium tartrate.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |