Silver halide photographic material containing selenium or tellurium compound

A silver halide photographic material comprising a silver halide emulsion layer provided on a support, wherein the silver halide emulsion is sensitized with a heterocyclic selenium or tellurium compound represented by the formula (Ia), (Ib), (Ic) or (Id):

• ##STR13## in which each of Ch.sup.1, Ch.sup.3, Ch.sup.6 and Ch.sup.12 independently is Se or Te;
• each of Ch.sup.2, Ch.sup.4, Ch.sup.5, Ch.sup.7, Ch.sup.8, Ch.sup.9, Ch.sup.10, Ch.sup.11, Ch.sup.13, Ch.sup.14 and Ch.sup.15 independently is O, S, Se or Te;
• the heterocyclic compound may have one or more substituent groups;
• and when the compound has two or more substituent groups, any two of the groups may be combined with each other to form a condensed heterocyclic ring.

A silver halide photographic material comprising a silver halide emulsion layer provided on a support, wherein the silver halide emulsion layer contains a tellurium compound represented by the formula (II):

• ##STR14## in which Ch.sup.21 is O, S or Se;
• each of R.sup.22 and R.sup.23 independently is an aliphatic group, an aromatic group or a heterocyclic group;
• each of R.sup.24 and R.sup.25 independently is a hydrogen atom, aliphatic group, an aromatic group, a heterocyclic group, a halogen atom, a cyano group, a nitro group, a sulfo group, a sulfino group, a carboxyl group, a phosphono group, an amino group, an ammonia group, a phosphonio group, a hydrazino group, --Ch.sup.26 R.sup.27, an acyl group, a carbamoyl group, an amido group, a sulfamoyl group, a sulfamido group, an aliphatic sulfonyl group, an aromatic sulfonyl group, an aliphatic sulfinyl group, an aromatic sulfinyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, --Ch.sup.28 COR.sup.29, an alkoxycarbonyl amino group, an aryloxycarbonylamino group or an ureido group;
• each of CH.sup.26 and Ch.sup.28 independently is O, S Se or Te;
• each of R.sup.27 and R.sup.29 independently is a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group;
• each of R.sup.22, R.sup.23, R.sup.24 and R.sup.25 may have one or more substituent groups;
• and any two of R.sup.22, R.sup.23, R.sup.24 and R.sup.25 may be combined with each other to form a heterocyclic ring.

A silver halide photographic material comprising a silver halide emulsion layer provided on a support, wherein the silver halide emulsion layer contains a selenium or tellurium compound represented by the formula (IIIa), (IIIb), (IVa), (IVb), (Va) or (Vb):

• ##STR15## in which each of Ch.sup.31, Ch.sup.36, Ch.sup.41, Ch.sup.46, Ch.sup.51 and Ch.sup.56 independently is Se or Te;
• X is O or S;
• each of R.sup.32, R.sup.37, R.sup.42, R.sup.47, R.sup.52, R.sup.53, R.sup.57 and R.sup.58 independently is an aliphatic group, an aromatic group, a heterocyclic group, a halogen atom, an amino group or --Ch.sup.61 R.sup.62 ;
• Ch.sup.61 is O, S, Se or Te;
• R.sup.62 is a hydrogen atom, an aliphatic group, an aromatic group or a heterocyclic group;
• each of R.sup.33, R.sup.43 and R.sup.54 independently is an aliphatic group, an aromatic group, a heterocyclic group, an acyl group, a carbamoyl group, a sulfamoyl group, an aliphatic sulfonyl group, an aromatic sulfonyl group, an aliphatic sulfinyl group, an aromatic sulfinyl group, an alkoxycarbonyl group or an aryloxycarbonyl group;
• each of R.sup.32, R.sup.33, R.sup.37, R.sup.42, R.sup.43, R.sup.47, R.sup.52, R.sup.53, R.sup.54, R.sup.57 and R.sup.58 may have one or more substituent groups;
• R.sup.52 and R.sup.53 may be combined with each other to form a heterocyclic ring;
• R.sup.57 and R.sup.58 may be combined with each other to form a heterocyclic ring;
• M.sup.1 is an l-valent cation;
• M.sup.2 is an m-valent cation;
• and M.sup.3 is an n-valent cation.