Morphology of silver developed from nanoparticle silver halide emulsion in fish gelatin medium

摘要

The morphology of silver developed from nanoparticle silver iodobromide emulsion in fish gelatin medium was observed by transmission electron microscopy in order to explore the effect of the protective gelatin state and the methionine (Met) component in it on the morphology of the developed silver. The silver developed in the liquid emulsion in which gelatin is in a state of colloidal solution showed a compact particle structure which could have resulted from solution physical devel- opment. The formation of filamentary silver was observed by the development of a dried emulsion coating with gelatin in a swollen state, which is characteristic of chemical development. The addition of Met, a sulphur-containing amino acid with reducing power found in the gelatin macromolecule, to the emulsion significantly accelerated the development of the coating which was attributed to shortening the induction period of the development. This acceleration disappeared if methionine sulphone, the oxidized product of Met, was added to the emulsion, instead of Met.