The effects of iodide addition on fog characteristics of cubic silver bromide grains

Citation
Jp. Li et al., The effects of iodide addition on fog characteristics of cubic silver bromide grains, J IMAG SC T, 43(1), 1999, pp. 61-69
Citations number
68
Categorie Soggetti
Optics & Acoustics
Journal title
JOURNAL OF IMAGING SCIENCE AND TECHNOLOGY
ISSN journal
10623701 → ACNP
Volume
43
Issue
1
Year of publication
1999
Pages
61 - 69
Database
ISI
SICI code
1062-3701(199901/02)43:1<61:TEOIAO>2.0.ZU;2-K
Abstract
Dependence of fog on chemical sensitization and iodide amount in cubic AgBr emulsions has been studied. Similar fog curve shapes were obtained from th e iodide-covered AgBr emulsions by varying the iodide amount and the sulfur -sensitized AgBr emulsions by varying the sulfur amount. Subsequent gold se nsitization of the two kinds of emulsions produces two fog peaks in the cur ves with varying the iodide or sulfur amount. The surface properties of the emulsion grains have been discussed with reference to fog formation. The o rigin of fog is attributed to the reactivity difference between the chemica l site and the bulk crystal surface. The reactivity sequences of different chemical sites were derived: Ag2S > AgI > AgBr > AgCa and Au-n > Ag-n, etc. Direct electron transfer development (DETD) and indirect electron transfer development (IETD) were supposed to be the two processes in development. B ased on the proposed mechanisms, the main experimental results were success fully explained with a distribution model of chemical impurities at the cub ic AgBr grain surface.