Silver halide photographic emulsion

• US 6,632,595 B2
• Filed: 03/12/2002
• Issued: 10/14/2003
• Est. Priority Date: 03/13/2001
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fuji Photo Film Co Limited (Fujifilm Holdings Corporation)
• Inventors: Furusawa, Genichi, Kikuchi, Makoto
• Primary Examiner(s): Schilling, Richard L.
• Application Number:
  US10/094,988
• Publication Number:
  US 20030013051A1
• Time in Patent Office: 581 Days
• Field of Search: 430/567, 430/568, 430/569
• US Class Current: 430/568
• CPC Class Codes: G03C 1/0051 Tabular grain emulsions
• CPC Class Codes: G03C 1/035 characterised by the crystal form or composition, e.g. mixed grain
• CPC Class Codes: G03C 2001/0056 Disclocations
• CPC Class Codes: G03C 2001/0058 Twinned crystal
• CPC Class Codes: G03C 2001/03535 Core-shell grains
• CPC Class Codes: G03C 2001/03552 Epitaxial junction grains; Protrusions or protruded grains
• CPC Class Codes: G03C 2200/03 111 crystal face

Abstract

A silver halide photographic emulsion comprising grains, wherein 50% or more (numerical ratio) of all the grains are occupied by tabular grains meeting the requirements (i) to (iii):

(i) a silver iodobromide or silver iodochlorobromide tabular grain having (111) faces as main planes and having two parallel twin planes;

(ii) a thickness of 0.12 μm or less; and

(iii) the tabular grains have a grain fringe portion meeting the requirements:

(a) the grain fringe portion has a phase of high silver iodide content in either of an upper region and a lower region than a region sandwiched between the two twin planes, and

(b) “A”, which represents the maximum local silver iodide content (mol %) in the phase of high silver iodide content, satisfies the relationship:

A−6.0≧B,

wherein “B” represents local silver iodide content (mol %) in an opposite part to the phase of high silver iodide content.

Claims

1. A silver halide photographic emulsion comprising grains, wherein 50% or more (numerical ratio) of all the grains are occupied by tabular grains each meeting the requirements (i) to (iii) below:

(i) a silver iodobromide or silver iodochlorobromide tabular grain having (111) faces as main planes and having two parallel twin planes;

(ii) a thickness of 0.12 μ

m or less; and

(iii) the tabular grains each have a grain fringe portion meeting the following requirements (a) and (b), the grain fringe portion being a grain peripheral portion extending from a grain side defining edge to an inside as much as a length corresponding to a grain thickness, when viewed in a direction perpendicular to the main planes;

(a) the grain fringe portion has a phase of high silver iodide content in either one of an upper region and a lower region than a region sandwiched between the two twin planes, and

(b) “

A”

, which represents the maximum local silver iodide content (mol %) in the phase of high silver iodide content, satisfies the relationship;

2. The silver halide photographic emulsion according to claim 1, wherein “

A” and

“

B”

satisfy the relationship;

3. The silver halide photographic emulsion according to claim 1, wherein said tabular grain thickness is 0.10 μ

m or less.

4. The silver halide photographic emulsion according to claim 1, wherein said tabular grain thickness is 0.08 μ

m or less.

5. The silver halide photographic emulsion according to claim 1, wherein said tabular grains further meet the following requirement (iv):

(iv) the tabular grains each have 10 or more dislocation lines per grain in the fringe portion.

6. The silver halide photographic emulsion according to claim 2, wherein said tabular grains further meet the following requirement (iv):

(iv) the tabular grains each have 10 or more dislocation lines per grain in the fringe portion.

7. The silver halide photographic emulsion according to claim 3, wherein said tabular grains further meet the following requirement (iv):

(iv) the tabular grains each have 10 or more dislocation lines per grain in the fringe portion.

8. The silver halide photographic emulsion according to claim 4, wherein said tabular grains further meet the following requirement (iv):

(iv) the tabular grains each have 10 or more dislocation lines per grain in the fringe portion.

9. The silver halide photographic emulsion according to claim 1, wherein said tabular grains further meet the following requirement (v):

(v) the tabular grains each have 30 or more dislocation lines per grain in the fringe portion.

10. The silver halide photographic emulsion according to claim 2, wherein said tabular grains further meet the following requirement (v):

(v) the tabular grains each have 30 or more dislocation lines per grain in the fringe portion.

11. The silver halide photographic emulsion according to claim 3, wherein said tabular grains further meet the following requirement (v):

(v) the tabular grains each have 30 or more dislocation lines per grain in the fringe portion.

12. The silver halide photographic emulsion according to claim 4, wherein said tabular grains further meet the following requirement (v):

(v) the tabular grains each have 30 or more dislocation lines per grain in the fringe portion.

13. The silver halide photographic emulsion according to claim 1, wherein said tabular grains occupying 50% or more (numerical ratio) of all the grains are produced by a method comprising forming, in the course of grain formation, one silver halide phase and another silver halide phase in the upper region and in the lower region than the region sandwiched between the two twin planes in the grain fringe portion, respectively, the silver halide phases having respective local silver iodide content maximum values whose difference is 25 mol % or more.

14. The silver halide photographic emulsion according to claim 1, wherein said tabular grains occupying 50% or more (numerical ratio) of all the grains are produced by a method comprising scooping out once, in the course of grain formation, either one of at least a part of the upper region and at least a part of the lower region than the region sandwiched between the two twin planes in the grain fringe portion, and thereafter recovering the scooped part.

15. The silver halide photographic emulsion according to claim 1, wherein said tabular grains occupying 50% or more (numerical ratio) of all the grains are produced by a method comprising forming, in the course of grain formation, silver halide epitaxy containing silver iodide at a position on either the upper region or the lower region of the grain fringe portion.

16. The silver halide photographic emulsion according to claim 1, wherein said tabular grains occupying 50% or more (numerical ratio) of all the grains are produced by a method comprising releasing iodide ions from an iodide ion-releasing agent, thereby forming epitaxy containing silver iodide in the course of grain formation.

17. A silver halide color photographic lightsensitive material comprising at least one layer containing a silver halide emulsion on a support, wherein at least one layer among the at least one layer contains the silver halide photographic emulsion according to claim 1.