Sensitization of Zn (II)-EDTA and Cd (II)-EDTA on silver bromide emulsion doped with oxalate

In the emulsifying process of AgBr microcrystals in the double-jet apparatus controlled by a microcomputer, a certain amount of oxalate salt was injected at specific time and pAg into a reactor to prepare AgBr grain emulsions in which oxalate ions were doped at subsurface of AgBr microcrystals, and which were sensitized respectively by sulfur plus gold, sulfur plus gold plus Zn (II)-EDTA or Cd (II)-EDTA, and dye. The results from the whole experiments and sensitometric results from these emulsions showed: 1) that sensitization of Zn (II)-EDTA or Cd (II)-EDTA on silver bromide emulsion was affirmed; 2) That a cooperation sensitization of Zn (II)-EDTA or Cd (II)-EDTA, sulfur plus gold, and dye could be carried out to make a higher level of sensitization; 3) That a cooperation sensitization of Zn (II)-EDTA or Cd (II)-EDTA, on the basis of (sulfur plus gold) and dye, with oxalate-doped was carried out to make a higher level of sensitization without any increase in the level of fog.