Sensitization on tabular silver iodine bromide emulsion doped with oxalate

In the emulsifying process of AgBrI 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 tabular AgBrI grain emulsions in which oxalate ions were doped at subsurface of AgBrI microcrystals. The observation results from the whole experiments and sensitometric results from these emulsions showed: 1) that the sensitivities (S_d) of oxalate-doped emulsions, relative to those (S₀) of the corresponding undoped ones as the controlled, regardless of whether it is sensitized chemically and spectrally, were remarkably increased(S_d/S₀≥1.5); 2) That fog level of oxalate-doped emulsions, regardless of whether it is primitive or sensitized chemically and spectrally, were kept low.