SILVER SULPHIDE MEMBRANE FOR THE DETERMINATION OF HALIDE IONS DURING PREPARATION OF PHOTOGRAPHIC EMULSIONS.

摘要

2075897 9112522 PCTABS00006 Silver sulphide crystalline membrane for the determination of halide ions and method of production. According to the invention, the membrane comprises silver sulphide doped with an ion capable of forming either with Ag+ or X- a salt which presents a much higher degree of insolubility than chemical species in solution. Preferably, the membrane also contains a hydrophobic compound which is resistant to reagents. The membrane is prepared by co-precipitating silver sulphide and the doping agent, homogenizing with the hydrophobic compound and then pressing. The membrane may be used in an electrode for the detection of halides during the preparation of photographic emulsions.