Abstract: In the present paper,the microwave photoconductivity signal intensity and the photoele-ctron lifetime of the fractionated polydispersed emulsion microcrystals were studied. It was found that with the decrease of grain size and iodide content,the photoconductivity,consequently the concentration of photoelectrons in emulsion microcrystals decreases,indicated the huge difference of different bunches of polydispersed emulsion in electronic conduction properties. The difference in the chemical ripening kinetics and the photographic characteristics of various bunches can be fairly well explained with the data of grain size,iodide content istribution,ionic conductivity,and the electronic properties reported here.

Key words: photographic chemistry, microwave photoconductivity, silver iodobromide-emulsion, photoelectron lifetimes