US3754918A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dye bleaching bath for the silver dye bleaching process
Assignee: Agfa Gevaert AG
•
Filing: 1971-07-28
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Granted: 1973-08-28
•
Expires: 1991-07-28
Abstract
Abstract Color photographic images are produced by the silver dye bleaching process in which the bleaching is accelerated with a bleaching bath containing substituted 1,5-diazanaphthalenes as defined below.
Inventors
- 👤 S Hunig
- 👤 M Heilmann
- 👤 P Bergthaller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:05
CPC Classifications
C; C07; C07D; C07D471/00; C07D471/02; C07D471/04; G; G03; G03C; G03C7/00; G03C7/28
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
19 words
The combination of claim 1 in which the concentration of the bleaching catalyst is between 5 and 200 mg/1.
Claim 2
Dependent Claim
17 words
The combination of claim 1 in which the bath has a pH of between 0 and 1.
Claim 3
Dependent Claim
16 words
The combination of claim 1 in which the bath contains potassium iodide as a silver-salt-forming agent.
Claim 4
Dependent Claim
14 words
The combination of claim 1 in which the bath contains a thiourea silver-complex-forming agent.
Claim 5
Dependent Claim
33 words
In the process for the production of photographic images by means of the silver dye bleaching process, the improvement according to which the dye bleaching bath used is the bath of claim 1.
Claim 6
Dependent Claim
17 words
The combination of claim 2 in which the bath has a pH of between 0 and 1.
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) | 1976-08-27 | 1977-02-26 | 1977-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-27 | 1981-02-26 | 1981-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-27 | 1985-02-26 | 1985-08-28 | $7700.00 | Window Closed / Lapsed |