Sensitivity and Sensitization of Silver Bromide Grains of Octahedral Sharp Doped with Oxalate Ions

摘要

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 octahedral AgBr grain emulsions in which oxalate ions were doped at subsurface of AgBr microcrystals. The sensitometric results from these emulsions showed:1) that the sensitivities (Sd) of oxalate-doped emulsions, relative to those (S0) of the corresponding undoped ones as the controlled, regardless of whether it is primitive, or sensitized chemically and spectrally, were remarkably increased; 2) that a cooperative sensitization by oxalate dopant, S+Au and dye without significant increase in fog level; was reconfirmed; 3) that the sensitivity gains (Sd/S0) of octahedral AgBr emulsions were more than those of cubic ones.