Use of tertiary phosphines in photographic silver dye bleach materials
AssigneeCiba-Geigy Corporation
InventorsChristoph Chylewski, Gerald Jan, Roland Kurzen, Max Meier, Matthias Schellenberg
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Abstract
A method of processing photographic silver dye bleach materials which have been exposed imagewise is provided. The process steps are (1) silver developing, (2) dye bleaching, (3) silver bleaching and (4) fixing. The treatment baths for the process steps (2), (3) and (4), or the combined treatment baths useful for process step (3) with at least one the process steps (2) or (4) contain water-soluble tertiary phosphines as silver ligands. These phosphines effect an acceleration of the dye and silver bleaching and they are further suitable stabilizers and optionally antioxidants which yield stable treatment baths.
Claims1
A phosphine of the formula ##STR33## and X.sub.2 is CNCH.sub.2 CH.sub.2 -- or CH.sub.3 OCH.sub.2 CH.sub.2 -- and M.sup..sym. is hydrogen, NH.sub.4.sup..sym., Na.sup..sym. or K.sup..sym., at least one of the W.sub.2 and X.sub.2 groups containing a cyano moiety.
Dependencies are inferred from the claim text.