Influence of redox buffer solutions on photographic sensivity.

Y.V. Fedorov, V.N. Zakharov

Proceedings of IS&T's 50-th Annual Conference, 1997, Cambridge, Massachusetts, USA, p.150-151.

ABSTRACT. According to the thermodynamic theory of photographic sensitivity, all three main stages of photographic process are stages of reduction of emulsion crystals resulting in formation of metallic silver phase. Thermal processing of emulsion at the stage of its chemical sensitization aid the process of partial reduction of AgHal microcrystals.The value of oversaturation with free silver is unambiguously determined by overpotential value with respect to the potential of massive silver electrode, reached during sensitization. Redox buffer solutions, depending on the value of created overpotential, are capable of influencing thedegree of oversaturation and, therefore, the sensitivity as well. The form of the sensitivity vs. overpotential dependence isdetermined by the mechanism of latent image formation. We consider here two variants: the first when the latent image centres formation follows the mechanism of the photoinduced formation of nuclei and the secong -the mechanism of the spontaneous formation of nuclei.

Laboratory of Structural Chemistry