Silver halide photographic emulsion

Abstract

A silver halide photographic emulsion containing silver halide grains formed in the presence of a silver halide solvent of the formula (I): ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each a subtituted or unsubstituted alkyl group, a substituted or unsubstituted alkenyl group (e.g., allyl group), a substituted or unsubstituted aryl group or a substituted or unsubstituted nitrogen-containing heterocyclic ring; or R.sub.1 and R.sub.2, R.sub.2 and R.sub.3, and R.sub.3 and R.sub.4 when taken together may form a 5- or 6-membered heterocyclic ring; provided at least one of R.sub. to R.sub.4 is a 5- or 6-membered nitrogen-containing heterocyclic ring, an alkyl group or aryl group substituted with an amino group, an alkyl grop substituted with a nitrogen-containing heterocyclic ring, or R.sub.1 and R.sub.2, R.sub.2 and R.sub.3, or R.sub.3 and R.sub.4 combine to form a 5- or 6-membered nitrogen-containing heterocyclic ring containing at least two nitrogen atoms.

Dependencies are inferred from the claim text.