Silver halide photographic material having specific silver halide structure

Claim 2

A silver halide photographic material comprising a support having thereon at least one light-sensitive silver halide emulsion layer containing chemically sensitized silver halide grain having a silver halide core portion comprising about 10 to 40 mol % silver iodide, substantially surrounded by a silver halide shell portion containing less silver iodide than the core portion and the silver halide of the surface region of the shell portion contains at least about 5 mol % silver iodide.

Claim 3

A silver halide photographic material as in claim 1, wherein the relative standard deviation of the iodide content distribution among grains is not more than about 50%.

Claim 4

A silver halide photographic material as in claim 1, wherein the content of silver iodide in the core portion is from about 15 to 40 mol %.

Claim 5

A silver halide photographic material as in claim 1, wherein the content of silver bromide in the core portion is at least 50 mol %.

Claim 6

A silver halide photographic material as in claim 1, wherein the core portion further contains at least one of silver bromochloride and silver bromide.

Claim 7

A silver halide photographic material as in claim 1, wherein the shell portion contains from about 0 to 10 mol % of silver iodide.

Claim 8

A silver halide photographic material as in claim 1, wherein the shell portion comprises at least one of silver chloride, silver chlorobromide and silver bromide.

Claim 9

A silver halide photographic material as in claim 7, wherein the content of silver iodide is not more than 5 mol %.

Claim 10

A silver halide photographic material as in claim 1, wherein the content of silver iodide in the silver holide surface region is from about 7 to 15 mol %.

Claim 11

A silver halide photographic material as in claim 9, wherein the content of silver iodide is not less than the silver iodide content in the core portion.

Claim 12

A silver halide photographic material as in claim 1, wherein the surface portion contains at least one of silver chloride, silver chlorobromide and silver bromide.

Claim 13

A silver halide photographic material as in claim 1, wherein the surface portion contains at least 40 mol % of silver bromide.

Claim 14

A silver halide photographic material as in claim 1, wherein the total content of silver iodide in the silver halide grains is at least about 7 mol %.

Claim 15

A silver halide photographic material as in claim 13, wherein the total content of silver iodide in the silver halide. graios is at most about 21 mol. %

Claim 16

A silver halide photographic material as in claim 1, wherein the emulsion contains tabular silver halide grains.

Claim 17

A silver halide photographic material as in claim 15, wherein the grains have a thickness of not more than about 0.5 µm, a diameter of at least 0.6 µm and an aspect ratio of at least 2, and the grains occupy at least about 50% of the total projected area of the silver halide grains in the emulsion.

Claim 18

A silver halide photographic material as in claim 1, wherein the emulsion is a monodisperse emulsion containing normal crystal grains and about 90% of the total silver halide grains have grain size within ±40% of the average grain size.

Claim 19

A silver halide photographic material as in claim 1, wherein the grain having a size of at least 1.0 µm are covered by a shell of at least 0.1 µm in thickness and grains having not more than 1.0 u.m are covered by a shell of at least 0.05 u.m.

Claim 20

A silver halide photographic material as in claim 1, wherein the ratio of silver content in the core portion to that the shell portion is in the range of from about 1:5:5:1.

Claim 21

A silver halide photographic material as in claim 1, wherein the silver halide grains are spectrally sensitized by at least one sensitizing dye selected from the group consisting of dyes represented by formula (I) or (II): wherein Z 1 and Z 2 each represents atomic group necessary for forming the same or different, substituted or substituted 5-or 6-membered, nitrogen-containing hetero rings, Q 1 represents an atomic group necessary for forming a 5 or 6-membered, nitrogen-containing ketomethylene ring, R 1 , R 2 , R 3 , and R 4 each represents a hydrogen atom a lower alkyl group a substituted or unsubstituted phenyl group a substituted or unsubstituted phenyl group, or aralkyl group; when l 1 represents 2 or 3 or when n represents 2 or 3, one R 1 and another R 1 , one R 2 and another R 2 , one R 3 and another R 3 , or one R 4 and another R 4 may be linked to each other to form a 5-or 6-membered ring optionally containing an oxygen atom, a sulfur atom, a nitrogen atom, R 5 , R 6 and R 7 , each represents a substituted or unsubstituted alkyl or alkenyl group containing up to 10 carbon atoms which may have an oxygen atom, a sulfur atom or a nitrogen atom in the carbon chain, l 1 and n 1 each represents 0 or a positive integer of 1 to 3, with l 1 + n 1 being 1 to 3, when l 1 represents 1, 2 or 3, R 5 and R 1 may be connected to each other to form a 5-or 6-membered ring, ji, k 1 , and m 1 each represent 0 or 1, X 1 represents an acid anion. r 1 represents 0 or 1; wherein Z 11 represents an atomic group necessary for forming a nitrogen-containing, substituted or unsubstituted 5-or 6-membered hetero ring, Q 11 represents an atomic group necessary for forming a nitrogen-containing, 5-or 6-membered ketomethylene ring, Q 12 represents an atomic group necessary for forming a nitrogen-containing, 5-or 6-membered ketomethylene ring, R 11 represents a hydrogen atom or an alkyl group containing up to 4 carbon atoms, R 12 represents a hydrogen atom, a substituted or unsubstituted phenyl or alkyl group and, when m 21 represents 2 or 3, plural R 12 groups may be linked to form a 5-or 6-membered ring optionally containing an oxygen atom, a sulfur atom or a nitrogen atom, R 13 represents a substituted or unsubstitutes alkyl, alkenyl or heteos ring group containing up to 10 carbon atoms and optionally containing an oxygen atom, a sulfur atom or a nitrogen atom in the carbon chain of the alkyl or alkenyl group, R 14 and R, 5 each has the same definition as R 13 , or each represents a hydrogen atom or substituted or unsubstitutes monocyclic aryl group, m 21 represents 0 or a positive integer of 1 to 3, j 21 represents 0 or 1, and n 21 represents 0 or 1, when m 21 represents a positive integer of 1 to 3, R 11 and R 13 may be linked to form a 5-or 6-membered ring.

Claim 22

A silver halide photographic material as in claim 1, wherein the emulsion contains a sulfur-containing silver halide solvent.

Claim 23

A silver halide photographic material as in claim 21, wherein said sulfur-containing silver halide solvent is contained in an amount from about 125 x 10 -4 mol to 5.0 x 10 -2 mol per mol of silver.

Claim 24

A silver halide photographic material as in claim 1, wherein the emulsion contains a 2-equivalent type coupler.