Silver halide emulsion stabilization

E. J. Birr, Stabilization of Photographic Silver Halide Emulsions. Focal Press, London and New York, 1974. 

Hydroxyhydroquinone and pyrogallol can be used for lining reactors for vinyl chloride suspension polymerization to prevent formation of polymer deposits on the reactor walls (98). Hydroxyhydroquinone and certain of its derivatives are useful as auxiliary developers for silver halide emulsions in photographic material their action is based on the dye diffusion-transfer process. The transferred picture has good contrast and stain-free highlights (99). 5-Acylhydroxyhydroquinones are useful as stabilizer components for poly(alkylene oxide)s (100). 

Coordination compounds and coordination chemistry are involved in a number of these steps. Chemical sensitizing agents, antifoggants and stabilizers are discussed separately. This discussion concerns silver halide emulsion precipitation and physical ripening methods. 

Metal complex formation can be used to stabilize an otherwise reactive or unstable organic developer, such as hydroquinone or p-phenylenediamine, to permit its incorporation into silver halide emulsion layers or adjacent layers. For example, catechols and hydroquinones can be mixed with several metal salts of lead(II), cadmium or barium and incorporated into emulsion layers. Treating the film with an activator solution containing an anion that forms an insoluble salt of the metal ion (S04 , liberates the organic developer.The structures of the complexes... 

G. Fischer, Stabilizers for Photographic Silver Halide Emulsions , Kluwer Academic/Plenum Publishers, New York (2004). 

Binder dispersant—photographic silver halide emulsions Dispersant—fluidizing agent Latex emulsifiers Shampoo foam stabilizers Dispersants coatings... 

Allen, C. F. H. Keimard, K. C. Stabilized photographic silver halide emulsions. U.S. Patent 2776211,1957. 

Ikeda, T. Silver halide emulsion containing cyanine dye for improved storage stability and high sensitivity and heat-developable photographic material. Jpn. Kokai Tokkyo Koho JP 2004094015, 2004. 

Like the more widely used 1,2,3-triazoles, many 1,2,4-triazole derivatives find application in photography thanks to the adsorption of thiones on silver halides, reactivity with silver compounds or the formation of disulfides as potential free radicals. Also 5-propargylthiol (344) stabilizes photographic emulsions (74GEP2304321). 

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