Patent US3628955A successfully refreshed from Google Patents.
US3628955A
Expired / Lapsed
US
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Inhibition of silvering in photographic solutions
Assignee: Eastman Kodak Co
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Filing: 1968-02-27
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Granted: 1971-12-21
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Expires: 1988-02-27
Abstract
Abstract Certain mercapto organic acids, such as mercaptoisobutyric acid, provide good antisludging action in photographic processing solutions.
Inventors
- 👤 Grant M Haist
- 👤 David A Pupo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 04:35
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/305
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
12 words
A liquid photographic processing solution as in claim 1 comprising a monobath.
Claim 2
Dependent Claim
23 words
A liquid photographic processing solution as in claim 1 comprising a monobath containing a silver halide developing agent and a thiosulfate fixing agent.
Claim 3
Dependent Claim
14 words
A liquid photographic processing solution as in claim 1 comprising a development activator solution.
Claim 4
Dependent Claim
13 words
A liquid photographic processing solution as in claim 1 comprising a developer solution.
Claim 5
Dependent Claim
17 words
A liquid photographic processing solution as in claim 1 wherein said mercapto organic acid is mercaptoisobutyric acid.
Claim 6
Dependent Claim
21 words
A liquid photographic processing solution as in claim 1 comprising a monobath and wherein said mercapto organic acid is mercaptoisobutyric acid.
Claim 7
Dependent Claim
26 words
A liquid photographic processing solution as in claim 1 comprising a monobath containing a thiosulfate fixing agent and wherein said mercapto organic acid is mercaptoisobutyric acid.
Claim 8
Dependent Claim
24 words
A liquid photographic processing solution as in claim 1 comprising a monobath containing 0.05 to 0.5 gram per liter of said mercapto organic acid.
Claim 9
Dependent Claim
36 words
A liquid photographic processing solution as in claim 1 comprising a monobath containing: a. mercaptoisobutyric acid, b. alkali metal thiosulfate, c. a silver halide developing agent, d. a development activator, and e. a gelatin hardening agent.
Claim 10
Dependent Claim
19 words
A liquid photographic processing solution as in claim 10 wherein said gelatin-hardening agent is a glutaraldehyde bis(alkali metal bisulfate).
Claim 11
Dependent Claim
15 words
A liquid photographic processing solution as in claim 1 also comprising a 3-pyrazolidone developing agent.
Claim 12
Dependent Claim
80 words
A photographic method comprising developing and fixing an image in an exposed photographic silver salt layer of a photographic element by contacting said photographic silver salt layer with a monobath resistant to sludging containing a mercapto organic acid of the formula: wherein R is hydrogen or lower alkyl; R1 is lower alkyl; and R2 and R3 are each selected from the group consisting of hydrogen, alkyl, amine, hydroxyl and halogen; m is zero or an integer from 1 to 5.
Claim 13
Dependent Claim
23 words
A photographic method as in claim 13 wherein said monobath comprises a thiosulfate fixing agent, a silver halide developing agent and mercaptoisobutyric acid.
Claim 14
Dependent Claim
20 words
A photographic method as in claim 13 wherein said photographic silver salt layer is a photographic silver halide emulsion layer.
Claim 15
Dependent Claim
98 words
A photographic method comprising developing and fixing an image in an exposed photographic silver salt layer of a photographic element containing a silver halide developing agent by contacting said photographic element with a photographic processing solution resistant to sludging comprising: a. a development activator, b. a silver halide fixing agent, and c. a mercapto organic acid of the formula: wherein R is hydrogen or lower alkyl; R1 is lower alkyl; and R2 and R3 are each selected from the group consisting of hydrogen, alkyl, amine, hydroxyl and halogen; m is zero or an integer from 1 to 5.
References Cited (Backward Citations)
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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) | 1974-12-20 | 1975-06-21 | 1975-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-12-20 | 1979-06-21 | 1979-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-12-20 | 1983-06-21 | 1983-12-21 | $7700.00 | Window Closed / Lapsed |