Process for processing photographic baths from color processes

Details Process for processing photographic baths from color processes Process for processing photographic baths from color processes

1997-05-16

1998-07-21

Le, Hoa Van

Radiation imagery chemistry: process, composition, or product th

Regenerating image processing composition

Bleach-fix

430398, 430399, G03C 744

Patent

active

057833745

ABSTRACT:
A process for the processing of spent photographic baths from color processes, namely bleaching or fixing baths with a preponderant content of amonium-Fe-EDTA (ethylene diamine tetraacetic acid) as the sequestering agent, fixing baths with a preponderant content of thiosulphates, particularly ammonium thiosulphate and optionally sodium thiosulphate, and developing baths with a preponderant content of sulfate, particularly sodium sulfite is proposed, which is characterized in that, following the deposition of the silver contained in the baths, the multipart starting solution is adjusted to a pH of approximately 13.5 to 14 using NaOH and the Fe(OH).sub.3 obtained after Fe complex decomposition is separated, the remaining, first intermediate solution is adjusted to a pH of 10 by adding acid and the resulting ammonia is separated, the remaining, second intermediate solution is brought to a pH of approximately 0.5 with concentrated HCl, the thiosulphates being decomposed into elementary sulphur and sulphurous acid and the sulphur is separated, the remaining, third intermediate solution is raised to a pH of approximately 1.5 with inorganic liquor and the crystallizing out EDTA is drawn off, the residual solution mixed with developing baths is raised to pH-3 and the sulfate contained therein is transformed into SO.sub.2, which is separated.

REFERENCES:
patent: 3700450 (1972-10-01), Cooley
patent: 3767401 (1973-10-01), Newman et al.
patent: 4013527 (1977-03-01), Idota et al.
patent: 4038079 (1977-07-01), Meckl et al.
patent: 4128464 (1978-12-01), Idota
patent: 4186007 (1980-01-01), Meckl et al.
patent: 4204930 (1980-05-01), Ono et al.
patent: 4217188 (1980-08-01), Ono
patent: 4256559 (1981-03-01), Ono et al.
patent: 4313808 (1982-02-01), Idemoto et al.
patent: 4680123 (1987-07-01), Wermicke et al.
patent: 5055382 (1991-10-01), Long et al.
patent: 5162106 (1992-11-01), Kunda et al.
patent: 5173157 (1992-12-01), Nevels

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