NEW TYPES OF DOPANTS IN SILVER HALIDE EMULSIONS

doi:10.7517/j.issn.1674-0475.2001.01.72

Abstract

Abstract: Two new types of dopants are introduced in this paper. One type is a transition metal complex dopant which can create shallow electron traps in silver halide grains. The other is a carboxylate organic compound which can create hole traps in the silver halide grains. Both types of traps can effectively prevent the photoelectrons and the holes from recombination and hence increase the efficiency of the latent image formation, resulting in significant increase of the sensitivity of the photographic emulsions. The principles of selecting dopants are presented. Some experimental results in patents are provided to illustrate the effects of dopants on the photographic properties of the silver halide emulsion.

Key words: dopant, shallow electron traps, hole traps, transition metal complex

CLC Number:

TQ57

DAI Hui, LIANG Bing, ZHUANG Si-yong . NEW TYPES OF DOPANTS IN SILVER HALIDE EMULSIONS[J]. Imaging Science and Photochemistry, 2001, 19(1): 72-78.

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