Ciba-geigy Ag

Matthias Schellenberg

Christoph Chylewski

Max Meier

Gerald Jan

Roland Kurzen

Rolf Steiger

Max Marthaler

Herbert Mollet

Meinrad Schar

Leslie F Mason

Robert Stanley Cook

David Kilcast

A photographic material for the silver dye bleach process comprises, in at least one layer, a colloidal dispersion of azo in gelatine, the ratio of azo dye to gelatine being 1:1 to 1:10.

Photographic material for the silver dye bleach process comprising an

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.

Use of tertiary phosphines in photographic silver dye bleach materials

A new method to produce photographic images is provided which comprises

Process for producing photographic images

A method for processing silver dye-bleach materials, with the process measures silver developing, dye bleaching, silver bleaching and fixing, wherein the silver and dye bleaching can be combined in a single treatment step is provided. For the silver bleaching or the combined dye and silver bleaching an acid formulation is used which has a pH value of at most 2 and contains a strong acid, a water-soluble iodide, optionally a water-soluble organic nitro compound, a non-quaternised quinoxaline or pyrazine, an anti-oxidant and at least one quaternary ammonium salt or a protonated tertiary organic nitrogen base. By this method the processing time can be shortened without impairing the quality of the colored images obtained.

Method for processing silver dye-bleach materials

Method of processing photographic silver dye bleach materials

The present invention relates to an oil-in-water emulsion which is suitable for processing photographic material. There is present or produced during the processing a substance which exerts its action on the photographic material from the aqueous phase. Contingent on the consumption the active substance is replenished or regenerated from the oily phase. The active substance is more readily soluble in the oily phase than in the aqueous one. The active substance may be, e.g., a dye bleach catalyst for silver dye bleach material or an alkylmercaptan, the latter acting as an antioxidant.

Preparation for the processing of photographic materials

The present invention relates to a simplified method for processing silver dye bleach material by (1) silver developing, (2) dye and silver bleaching (3) silver fixing and (4) soaking. The sequence (1), (2), (3), (4) is followed and the bleaching bath (2) contains (a) a strong acid, (b) a water-soluble iodide, (c) a water-soluble oxidizing agent (d) an antioxidant and (e) a dye bleach catalyst.

Method for processing silver dye bleach materials

The present invention relates to a process for fixing silver iodide containing photographic material with a fixing bath. The bath contains, in addition to a compound capable of forming soluble silver complexes, at least one organic solvent, preferably N-methylpyrrolidone. The organic solvent increases the speed of dissolution of the silver iodide.

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Marly, Switzerland

Matthias Schellenberg