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Patent US4155764A successfully refreshed from Google Patents.
US4155764A
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Photographic color developer composition
Assignee: Agfa Gevaert AG
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Filing: 1977-05-17
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Granted: 1979-05-22
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Expires: 1997-05-17
Abstract
Abstract A photographic color developer composition containing a color developer compound and an antioxidant wherein it contains a water-soluble enolizable α-aminocarbonyl compound as antioxidant is provided. Resistance to atmospheric oxygen of photographic color developer baths is improved.
Inventors
- 👤 Arnfried Melzer
- 👤 Erwin Schon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:58
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/407; G03C7/413; G03C5/00; G03C5/26; G03C5/29; G03C5/305
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
168 words
A photographic color developer composition for aqueous color development containing a developer compound of the p-phenylene diamine series and having a water-soluble enolisable α-aminocarbonyl compound for increasing the effectiveness of the developer compound and enhancing the suitability of the composition for obtaining improved color development, wherein said water-soluble enolisable α-aminocarbonyl compound has the following structural formula: ##STR8## in which R 1 and R 2 are the same or different and represent hydrogen, alkyl or aryl; R 3 is hydrogen or an alkyl group; and R 4 is hydrogen, alkyl, or aryl; R 1 , r 2 , r 3 and R 4 not being simultaneously hydrogen or in which R 1 and R 2 together represent the atoms to complete a heterocyclic ring, and/or R 2 and R 3 together represent the atoms to complete a heterocyclic ring, and/or R 3 and R 4 together represent the atoms to complete a carbocyclic ring, and/or R 4 and R 1 together represent the atoms to complete a heterocyclic ring.
Claim 2
Dependent Claim
168 words
A photographic color developer composition for aqueous color development containing a developer compound of the p-phenylene diamine series and having a water-soluble enolisable α-aminocarbonyl compound for increasing the effectiveness of the developer compound and enhancing the suitability of the composition for obtaining improved color development, wherein said water-soluble enolisable α-aminocarbonyl compound has the following structural formula: ##STR8## in which R 1 and R 2 are the same or different and represent hydrogen, alkyl or aryl; R 3 is hydrogen or an alkyl group; and R 4 is hydrogen, alkyl, or aryl; R 1 , r 2 , r 3 and R 4 not being simultaneously hydrogen or in which R 1 and R 2 together represent the atoms to complete a heterocyclic ring, and/or R 2 and R 3 together represent the atoms to complete a heterocyclic ring, and/or R 3 and R 4 together represent the atoms to complete a carbocyclic ring, and/or R 4 and R 1 together represent the atoms to complete a heterocyclic ring.
Claim 3
Dependent Claim
26 words
A colour developer composition as claimed in claim 1, wherein at least one of the radicals R 3 and R 4 represents a hydroxyl-substituted alkyl radical.
Claim 4
Dependent Claim
17 words
A colour developer composition as claimed in claim 1, wherein it contains D-glucosamine or 1-deoxy-1-piperidino-D-fructose as antioxidant.
References Cited (Backward Citations)
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US2936308A
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US3068100A
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US3582333A
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US3664835A
Cited
US3700442A
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US3846129A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-21 | 1982-11-20 | 1983-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-21 | 1986-11-20 | 1987-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-21 | 1990-11-20 | 1991-05-22 | $7700.00 | Window Closed / Lapsed |