Development of photographic materials in the case of an elevated temperature

摘要

1395161 Photographic silver halide development AGFA-GEVAERT 15 Sept 1972 [17 Sept 1971] 43518/71 Heading G2C [Also in Division C2] An exposed photographic element comprising a support and at least one photographic silver halide emulsion is developed at above 30‹C in the presence of at least one nitrile compound selected from: (a) benzene compounds carrying at least two CN groups on the benzene nucleus, (b) #-deficient heterocycles carrying at least one CN group on the heterocyclic nucleus and (c) compounds of the formula:- NC-C(R 1 )=CHR 2 where R 1 is CN or a #-deficient heterocycle; and R2 is optionally substituted aryl or heterocyclyl. The nitrile compound is preferably present in the silver halide emulsion, but may be present in a gelatine anti-stress layer, intermediate layer or filter layer. 16 specific nitrile compounds are disclosed. The silver halide emulsion may contain 5-methyl-7-hydroxy-5-triazolo [1, 5-a] pyrimidine and mercury cyanide (see Examples). The nitrile compounds have a favourable effect on fog and/or speed and/or gradation.