Patent US4163023A successfully refreshed from Google Patents.
US4163023A
Expired / Lapsed
US
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Treatment of photographic processing solutions
Assignee: Fujifilm Holdings Corp
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Filing: 1976-12-02
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Granted: 1979-07-31
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Expires: 1996-12-02
Abstract
Abstract A process of selectively separating a developing agent and/or a color development accelerator such as benzyl alcohol, etc., from photographic processing solutions containing these materials by bringing the processing solutions into contact with a copolymer selected from the group consisting of a styrenedivinylbenzene copolymer and a methacrylic acid monoestermethacrylic acid polyester copolymer. The developing agent thus adsorbed on the copolymer can be recovered therefrom by treating the copolymer with, e.g., diluted sulfuric acid.
Inventors
- 👤 Akira Endo
- 👤 Tohru Kitahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:33
CPC Classifications
G; G03; G03C; G03C5/00; G03C5/26; G03C5/29; G03C5/31
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
89 words
A process of selectively separating a p-phenylene diamine derivative from a photographic processing solution which comprises bringing the photographic processing composition into contact with a porous copolymer of a monoester of a monohydric alcohol or polyhydric alcohol and methacrylic acid and a polyester of a polyhydric alcohol and methacrylic acid, said copolymer being a porous copolymer having a pore volume of about 0.2 to about 1.5 ml/g, a specific area of about 100 to about 700 m 2 /g and a pore diameter of 30 to about 2,000 A.
Claim 2
Dependent Claim
89 words
A process of selectively separating a p-phenylene diamine derivative from a photographic processing solution which comprises bringing the photographic processing composition into contact with a porous copolymer of a monoester of a monohydric alcohol or polyhydric alcohol and methacrylic acid and a polyester of a polyhydric alcohol and methacrylic acid, said copolymer being a porous copolymer having a pore volume of about 0.2 to about 1.5 ml/g, a specific area of about 100 to about 700 m 2 /g and a pore diameter of 30 to about 2,000 A.
Claim 3
Dependent Claim
29 words
The process as set forth in claim 1, in which the photographic processing solution is a developer solution containing both of a developing agent and a color development accelerator.
Claim 4
Dependent Claim
30 words
The process as set forth in claim 1, in which the photographic processing solution is a color developer solution containing both a color developing agent and a color development accelerator.
Claim 5
Dependent Claim
34 words
The process as set forth in claim 1, in which the photographic processing solution is brought into contact with the copolymer by passing the processing solution through a column having the copolymer packed therein.
Claim 6
Dependent Claim
32 words
The process as set forth in claim 1, in which the photographic processing solution is brought into contact with the copolymer by placing the copolymer in the processing solution followed by stirring.
Claim 7
Dependent Claim
38 words
The process as set forth in claim 1, further including regenerating the copolymer brought into contact with the photographic processing solution by treating the copolymer with diluted sulfuric acid and water and repeatedly reusing the copolymer thus regenerated.
Claim 8
Dependent Claim
28 words
The process as set forth in claim 1, including recovering the p-phenylene diamine derivative thus adsorbed on the copolymer therefrom by treating the copolymer with diluted sulfuric acid.
Claim 9
Dependent Claim
13 words
The process of claim 1 wherein the photographic processing solution is a developer.
Claim 10
Dependent Claim
20 words
The process of claim 1 wherein the p-phenylene diamine derivative is removed by treating the copolymer with aqueous inorganic acid.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-07-30 | 1983-01-29 | 1983-07-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-07-30 | 1987-01-29 | 1987-07-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-07-30 | 1991-01-29 | 1991-07-31 | $7700.00 | Window Closed / Lapsed |