The Rate of Sulphide Formation During Photographic Sulphur Sensitization: Measurement of Proton Evolution

A method for measuring the production of protons in a photoemulsion has been applied to the measurement of the sulphur senSitizatIOn reaction. The formation of sulphide from conventional quantities of sensitizer was followed continuously in the digesting emulsion. Reactions of several different sensitizers generally obeyed first order kinetics, although in some cases an induction period was obferved. The generally written reaction for thiosulphate was confirmed. The results did not support a sensitization mechanism involving en lanced reaction at the sensitivity specks.