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US3816134A
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Photographic color developing solutions containing p-toluenesulfonic acid salts of p-phenylenediamines
Assignee: Eastman Kodak Co
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Filing: 1971-12-03
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Granted: 1974-06-11
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Expires: 1991-12-03
Abstract
Abstract The p-toluenesulfonic acid salts of certain p-phenylenediamine color developing agents have been found to possess extraordinarily and unexpectedly high solubility in aqueous alkaline solution. Thus, extremely concentrated solutions of these materials can be prepared to provide developer ''''concentrates'''' which are extremely economical to ship and working developer solutions which possess abnormally high developing agent concentrations and which are therefore capable of producing unusually high dye density levels in very short periods of time. Specifically preferred among these pphenylenediamine salts are the di-p-toluenesulfonic acid salts of 3-alkyl and 3-alkoxy N-alkyl-N-alkoxyalkyl-p-phenylenediamine developing agents.
Inventors
- 👤 D Schellenberg
- 👤 R Bent
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:06
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/407; G03C7/413; G03C7/4136
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
16 words
The photographic color developing solution of claim 1 wherein said p-toluenesulfonic acid salt has the formula:
Claim 2
Dependent Claim
1 words
N-Ethyl-N-methoxybutyl-3-methyl-p-phenylenediamine;
Claim 3
Dependent Claim
1 words
N-Ethyl-N-methoxybutyl-3-methyl-p-phenylenediamine;
Claim 4
Dependent Claim
1 words
N-Ethyl-N-ethoxyethyl-3-methyl-p-phenylenediamine;
Claim 5
Dependent Claim
1 words
N-Ethyl-N-ethoxyethyl-3-methyl-p-phenylenediamine;
Claim 6
Dependent Claim
27 words
The photographic color developing solution of claim 1 wherein said p-toluenesulfonic acid salt is a di-p-toluenesulfonic acid salt of a member selected from the group consisting of:
Claim 7
Dependent Claim
1 words
N-Ethyl-N-methoxyethyl-3-n-propyl-p-phenylenediamine;
Claim 8
Dependent Claim
1 words
N-Ethyl-N-methoxyethyl-3-n-propyl-p-phenylenediamine;
Claim 9
Dependent Claim
17 words
The photographic color developing solution of claim 1 further including a stabilizing amount of a water-soluble sulfite.
Claim 10
Dependent Claim
19 words
An aqueous alkaline photographic color developing solution containing, as the color developing agent, the di-p-toluenesulfonic acid salt of N-ethyl-N-methoxyethyl-3-methyl-p-phenylenediamine.
Claim 11
Dependent Claim
2 words
N-ethyl-N-methoxyethyl-3-methoxy-p-phenylenediamine; and
Claim 12
Dependent Claim
2 words
N-Ethyl-N-methoxyethyl-3-methoxy-p-phenylenediamine; and
Claim 13
Dependent Claim
1 words
N-Ethyl-N-butoxyethyl-3-methyl-p-phenylenediamine.
Claim 14
Dependent Claim
1 words
N-Ethyl-N-butoxyethyl-3-methyl-p-phenylenediamine.
Claim 15
Dependent Claim
57 words
In a process of color developing a photographic element by contacting said element with an aqeuous alkaline solution of a salt of a p-phenylenediamine color developing agent in the presence of a coupler that reacts with oxidized color developing agent to form a dye, the improvement wherein said salt is a p-toluenesulfonic acid salt of the formula:
Claim 16
Dependent Claim
11 words
The process of claim 6 wherein said salt has the formula:
Claim 17
Dependent Claim
22 words
The process of claim 6 wherein said salt is a di-p-toluenesulfonic acid salt of a member selected from the group consisting of:
Claim 18
Dependent Claim
15 words
The process of claim 6 wherein said salt is the di-p-toluenesulfonic acid salt of N-ethyl-N-methoxyethyl-3-methyl-p-phenylenediamine.
References Cited (Backward Citations)
US3656950A
Cited
US3658525A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-10 | 1977-12-10 | 1978-06-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-10 | 1981-12-10 | 1982-06-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-10 | 1985-12-10 | 1986-06-11 | $7700.00 | Window Closed / Lapsed |