EP0128720A2
Expired / Lapsed
EP
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Method and apparatus for separating and recovering color developing agent
Assignee: Konica Minolta Inc
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Filing: 1984-06-04
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Granted: —
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Expires: 2004-06-04
Abstract
Abstract A method and apparatus for separating and recovering a color developing solution from a color photographic processing solution with the said of a cation exchange resin are disclosed. Said solution has a pH of not higher than 8.0 and is brought into contact with a cation exchange resin, which is in turn brought into contact with an alkali solution having a pH of not lower than 9.0.
Inventors
- 👤 Christer Ernstson
- 👤 Yousuke Sadahiro
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 12:08
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/44
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
31 words
A method of separating a color developing agent from a solution containing it at a pH not greater than 8.0 by bringing said solution into contact with a cation exchange resin.
Claim 2
Independent Claim
31 words
A method of separating a color developing agent from a solution containing it at a pH not greater than 8.0 by bringing said solution into contact with a cation exchange resin.
Claim 3
Dependent Claim
23 words
A method according to Claim 1, wherein said cation exchange resin has a sulfonic acid group or a phosphonic acid group or both.
Claim 4
Dependent Claim
17 words
A method according to Claim 1 or 2, wherein said cation exchange resin is a styrene-divinylbenzene copolymer.
Claim 5
Dependent Claim
17 words
A method according to Claim 1, 2 or 3, wherein said color developing agent is a p-phenylenediamine.
Claim 6
Dependent Claim
25 words
A method according to Claim 1, 2, 3 or 4, wherein said solution has a salt concentration of not greater than 0.05 mol per liter.
Claim 7
Independent Claim
39 words
A method according to any one of claims 1 to 5 wherein after being brought into contact with said solution, the cation exchange resin is brought into contact with an alkali solution having a pH of at least 9.0.
Claim 8
Dependent Claim
15 words
A method according to claim 6 wherein said alkali solution is a color developing solution.
Claim 9
Independent Claim
50 words
An apparatus for recovering a color developing agent from a solution containing it comprising a tank for accommodating a waste photographic processing solution having a pH of not greater than 8.0 and at least one column adapted to bring said processing solution into contact with a cation exchange resin therein.
Claim 10
Independent Claim
50 words
An apparatus for recovering a color developing agent from a solution containing it comprising a tank for accommodating a waste photographic processing solution having a pH of not greater than 8.0 and at least one column adapted to bring said processing solution into contact with a cation exchange resin therein.
Claim 11
Dependent Claim
41 words
An apparatus according to Claim 8, which further includes a tank for accommodating a solution for adjusting the pH of the waste photographic processing solution and means for transferring said solution to a tank for accommodating said waste photographic processing solution.
Claim 12
Dependent Claim
22 words
An apparatus according to Claim 8 or 9, wherein said tank for accommodating the waste photographic processing solution includes a pH detector.
Claim 13
Independent Claim
70 words
An apparatus according to any one of Claims 8 to 10, which further includes a tank for accommodating an alkali solution having a pH of at least 9.0 for use in desorbing the color developing agent from the cation exchange resin, and a tank adapted to receive the alkali solution with any desorbed color developing agent after the alkali solution has been brought into contact with the cation exchange resin.
References Cited (Backward Citations)
No citation records indexed.
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