CONVERSION OF POSITIVE HOLE TO ELECTRON IN THE PROCESS OF LATENT IMAGE FORMATION

doi:10.7517/j.issn.1674-0475.2002.01.46

Abstract

Abstract: In the imaging system of silver halide, photon generated positive holes have been considered as a kind of species which play a negative role to cause inefficiency of latent image formation via recombination with electrons, regressive reaction with silver clusters and so on. Recently, some kind of novel sensitization technique that might be called as a conversion of hole to electron has been developed and are greatly interested in. So far 3 kinds of compounds have been found to act as a chemical converter. These are: 1) silver dimmer (Ag₂); 2) compounds of carboxylic acids including formic acid; 3)FED compounds, i.e fragmentable two electron donors. Each of these compunds possesses two elementary functions: trapping hole and releasing an extra electron through conversion when it is adsorbed or introduced into silver halide crystals. In this paper, features, mechanism and effect etc. of these converters are reviewed.

Key words: molecular type of chemical converters, chemical sensitization, imaging system of silver halide

CLC Number:

TQ57

XIA Pei-jie, GUO Hong, YAO Lin-hui, ZHAO Wen-fang. CONVERSION OF POSITIVE HOLE TO ELECTRON IN THE PROCESS OF LATENT IMAGE FORMATION[J]. Imaging Science and Photochemistry, 2002, 20(1): 46-59.

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