Integrated chemical system approach to silver halide emulsions

We investigate the materials and techniques available for construction of integrated chemical system (ICS) [1] based on silver halides. A typical ICS consists of a number of components, each serving a different function. A list of these, with some examples, includes the following: supports, catalysts, charge carriers and mediators, linking and coupling agents, photosensitive centers, electro-active centers, chemically sensitive centers. Electrochemical indicator devices as well as electrolytic sensitization [2] and redox properties of photographic emulsion are analyzed. Photographic film on the base of ultra-fine grained AgBr crystals is another example of ICS. This ICS could be useful to protect eyes under powerful flash action. In some ICSs, electrons or ions are transferred between species or across membranes. This charge transfer can be facilitated by appropriate mediators. Model photosensitizers could be such mediators. Structural-dynamics characteristic of exited states of photosensitizers and perspectives of its application in modem ICSs are given.