JPH02230136A - Silver halide photographic sensitive material having high sensitivity and high graininess - Google Patents

Abstract

PURPOSE:To improve the sensitivity and graininess of the photosensitive material by using an emulsion which contains specific silver iodobromide particles and has a specific X-ray diffraction peak. CONSTITUTION:This photosensitive material is formed by using the silver halide emulsion contg. the silver bromide of >=3 phases of different compsns. or the silver iodobromide particles having the phases consisting of silver iodobromide in >=1 layers of the emulsion layers. The emulsion, the diffraction signals of which by the X-ray diffraction method of the emulsion powder have >=3 max. diffraction intensity based on the diffraction peak corresponding to the max. iodine phase, the diffraction peak corresponding to the min. iodine phase and the diffraction peak corresponding to >=1 iodine phases consisting of the intermediate compsn. thereof and >=2 min. diffraction intensity between the same is used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a silver halide photographic material, and more particularly to a silver halide photographic material having high sensitivity and improved graininess.

[Conventional technology]

There is an increasing demand for improved image quality for silver halide photographic materials. In particular, the commercialization of high-sensitivity films with ISO 1000 or higher in the field of color negative film and the spread of small format compact cameras such as disc film have led to an expansion of photographic opportunities, but on the other hand, the image quality of finished prints has deteriorated and improvements have been made. is desired. In particular, much research has been conducted on silver halide emulsions regarding graininess, which is an important factor determining the quality of color photographic images.

Silver iodobromide emulsions containing 5 mol % or more of silver iodide are already known as /X silver halide emulsions which are highly sensitive and have excellent graininess. As further improved silver iodobromide emulsions, core/shell type silver halide emulsions containing 5 mol % or more of silver iodide have been actively researched. In particular, much research has been conducted on core/shell type silver iodobromide emulsions having an internal phase containing a high silver iodide content of 10 mol % or more for use in color negative films.

JP-A-61-245151 discloses a core/shell type emulsion with improved graininess, and JP-A-60-1433 discloses a core/shell emulsion with improved graininess.
No. 31, No. 60-147727, No. 60-25403
No. 2 discloses a core/shell emulsion with a high silver iodide content in the core portion.

However, these emulsions were still unsatisfactory in terms of sensitivity and graininess.

The present inventors investigated the cause of this in detail and found that the former is caused by homogenization of the high iodine phase and the low iodine phase during the preparation of a core/shell emulsion having a core with a high silver iodide content. It has been found that this method has the disadvantage of easily producing silver halide grains with an unclear phase structure. In addition, regarding the latter, even if the separation between the high-iodity phase and the low-iodity phase is clear,
It was found that the silver halide grains had a separation of substantially two different iodide phases.

[Object of the Invention] An object of the present invention is to provide a silver halide photographic material with high sensitivity and high graininess.

[Structure of the invention]

As a result of extensive studies, the present inventors have determined that the object of the present invention is to provide a silver halide emulsion containing silver iodobromide grains having three or more phases of different compositions of silver bromide or silver iodobromide. ,
In a diffraction signal obtained by powder X-ray diffraction, a diffraction peak corresponding to the highest iodine phase, a diffraction peak corresponding to the lowest iodine phase, and a composition intermediate between the highest iodine phase and the lowest iodine phase, or At least one emulsion layer containing an emulsion having three or more diffraction maxima based on diffraction peaks corresponding to a plurality of iodide phases and two or more diffraction minima between them.
It has been found that this can be achieved by a silver halide photographic material characterized by having layers.

In the present invention, at least one of the silver halide emulsion layers contains the silver iodobromide emulsion of the present invention.

Regarding the method of measuring powder X-ray diffraction images, for example, "New Experimental Chemistry Course, Basic Technology 5, Structural Analysis" (Marupu 197
The synchrotron orbital synchrotron radiation from the storage ring described on page 81 of 7) is made monochromatic with a monochromator using a single crystal described on pages 83-84 of the same magazine; Can be done.

In the measurements of the present invention, powder X-ray diffraction of silicon (111) is performed using X-rays with a wavelength of 1.4877A obtained by diffracting synchrotron orbital synchrotron radiation twice with a curved silicon single crystal (111). was measured, and the half-width at 1; was 0.043° (2θ).

A specific example of the X-ray diffraction method using synchrotron orbital synchrotron radiation can be found in the 7 Oton Factory Activity Report. Volume 3. 105 (1985). In addition, an X-ray monochromator using a single crystal is available from the International Tables for X-ray Crystallography.
Tables For X-Ray Crystal
3, pp. 79-86.

The silver halide emulsion in the present invention is composed of silver iodobromide (42
0) The diffraction signals corresponding to the diffraction lines are a diffraction peak corresponding to the highest iodine phase, a diffraction peak corresponding to the lowest iodine phase, and an iodine phase with a composition intermediate between the highest iodine phase and the lowest iodine phase. One or more corresponding diffraction peaks have a total of three or more diffraction maxima and two or more minima therebetween. It is preferable that the diffraction intensity corresponding to the phase giving the highest intensity among the diffraction maxima is 1 to 50 with respect to the diffraction intensity corresponding to the phase giving the lowest intensity among the diffraction maxima,
More preferably 1 to 20, particularly preferably 1 to 1
This is the case of O.

In the present invention, for an emulsion having a clear phase structure of three or more phases, it is more preferable that the diffraction intensity of the minimum value sandwiched between any two adjacent diffraction maxima is the same as that of the two adjacent diffraction maxima (peaks). Of these, it is preferable that the strength is 95% or less of the weaker one. More preferably, it is 90% or less.

Also, equipment noise is not counted.

The phase structure of silver bromide or silver iodobromide having three or more phases in the present invention can be determined by an X-ray diffraction method.

An example of applying the X-ray diffraction method to silver halide grains is given by H. It is described in Hirsch's Journal of 7 Otographic Science, Volume 1θ (1962), pages 129 onwards. When the lattice constant is determined by the halogen composition, a diffraction peak occurs at a diffraction angle that satisfies Black's condition (2dsinθ=nλ).

Even in the case of an emulsion in which many types of grains having different halogen compositions coexist, each consisting of a uniform phase, a plurality of peaks may appear in the X-ray diffraction.

Such emulsions cannot exhibit the excellent photographic performance obtained by the present invention.

To determine whether a silver halide emulsion is an emulsion according to the present invention or an emulsion in which various types of silver halide grains as described above coexist, in addition to the
tron-Probe Micro An
This is possible by using the Alyzer method).

This method enables elemental analysis of extremely small parts compared to X-ray analysis using electron beam excitation, in which a well-dispersed sample is prepared so that the emulsion grains do not come into contact with each other, and the sample is irradiated with an electron beam.

By this method, the halogen composition of each particle can be determined by determining the characteristic X-ray intensities of silver and iodine emitted from each particle.

By confirming the halogen composition of at least 50@ grains by the EPMA method, it can be determined whether the emulsion is an emulsion according to the present invention.

In the emulsion of the present invention, it is preferable that the iodine content among the grains is more uniform. When the distribution of iodine content between particles is measured by the EMPA method, the relative standard deviation is preferably 50% or less, more preferably 35% or less, and particularly preferably 20% or less.

Preferred halogen compositions of the silver halide grains having a three-phase or more phase structure according to the present invention are as follows.

The silver iodobromide emulsion of the present invention is a grain composed of a highest iodide phase, a lowest iodide phase, and an intermediate iodide phase between them, and the intermediate iodide phase is composed of one or more phases. formed by. The highest iodide phase, the lowest iodide phase, and the intermediate iodide phase have different silver iodide contents.

The silver iodide content of the highest iodide phase is preferably 10 mol% or more, more preferably 15 to 45 mol%, particularly preferably 20 to 40 mol%. The silver iodide content of the lowest iodide phase is 6 mol% or less, more preferably 0 to 3 mol%.
It is. The proportion of the lowest iodide phase in the silver halide grains of the present invention is preferably 10 to 80% by volume, more preferably 15 to 70%, particularly preferably 20 to 60%.

The proportion of the highest iodide phase is Iθ~80 in the total grain volume.
%, more preferably 20 to 50%.

The silver iodide content of the intermediate iodide phase is 3 mol% or more, expressed as the difference in silver iodide content between the highest iodide phase and the intermediate iodide phase, and between the intermediate iodide phase and the lowest iodide phase, respectively. are preferred, and more preferably 5 mol% or more, respectively.

The preferred volume of the intermediate iodide phase is 5-60% of the total grain.
, more preferably 20 to 50%.

The silver halide grains of the present invention may be normal crystals such as cubes, tetradecahedrons, and octahedrons, may be composed of twin crystals, or may be a mixture thereof, but are preferably normal crystals. .

In the silver halide grains of the present invention, the highest iodide phase may be present anywhere within the grain, but it is preferably present as an internal core within the grain. Further, the lowest iodide phase may exist anywhere within the grain, but it is preferably present as an outer shell outside the inner core. The intermediate iodide phase or phases may also be present anywhere within the grain, but are preferably present as an intermediate layer between the inner core and the outer shell, and are also preferably present inside the inner core. , or can exist in both.

The silver halide emulsion of the present invention is silver iodobromide, and the average silver iodide content is preferably 5 mol % or more, more preferably 6 to 15 mol %. Further, silver chloride can be contained within a range that does not impair the effects of the present invention.

The silver halide grains according to the present invention are preferably core/shell emulsions, and the manufacturing method thereof is disclosed in JP-A-59-177.
No. 535, No. 60-138538, No. 59-5223
8, No. 60-143331, No. 60-35726, No. 60-258536, No. 61-245151, etc. can be used. That is, a method can be used in which a seed emulsion is grown by a double jet method while controlling Ag and pl.

In producing the silver halide emulsion of the present invention, p at the time of production is
Control of Ag is extremely important.

The pAg during core growth is preferably 6 to IO, and the pAg during shell growth is preferably 9 to 11. The pAg change between the core and the shell during formation may be changed stepwise or continuously, but it is preferable to change it continuously.

In producing the silver halide emulsion of the present invention, stirring conditions during production are extremely important. As a stirring device, JP-A-6
It is preferable to use the stirring device shown in No. 2-160128 and set the stirring rotation speed to 500 to 1.200 revolutions/minute.

Furthermore, when a core/shell type silver halide emulsion is grown starting from seed grains as in the method described in JP-A-60-138538, the center of the grains may have a halogen composition region different from that of the core. obtain.

In such a case, the halogen composition of the seed grains may be of any composition such as silver bromide, silver iodobromide, silver chloroiodobromide, silver chlorobromide, or silver chloride, but if the silver iodide content is Silver iodobromide or silver bromide of less than 10 mol % is preferred.

The proportion of the seed grains in the total silver halide is 50% by volume.
% or less is preferable, and 10% or less is particularly preferable.

Known silver halide solvents such as ammonia, thioether, thiourea, etc. can be present during the growth of silver halide grains.

During the process of grain formation and/or growth, silver halide grains are produced using cadmium salts, zinc salts, lead salts, thallium salts, iridium salts (including complex salts), rhodium salts (including complex salts), and iron salts ( By adding at least one metal ion selected from the group consisting of complex salts, these metal elements can be contained inside the particles and/or in the particle surface layer, and by placing the particles in an appropriate reducing atmosphere. Reduction sensitizing nuclei can be provided inside and/or on the particle surface.

Unnecessary soluble salts may be removed from the silver halide emulsion after the growth of silver halide grains is completed, or they may be left contained. When removing the salts, Research Disclosure (Research Disclosure) is required.
Closure (hereinafter abbreviated as RD) can be carried out based on the method described in Section H of No. 17643.

The silver halide grains may be grains in which a latent image is mainly formed on the surface or grains in which the latent image is mainly formed inside the grain, and the size of the silver halide grains is as follows:
The diameter is 0.05 to 30μ, preferably 0.1 to 20μ.

As the silver halide emulsion of the present invention, any one can be used, such as a polydisperse emulsion with a wide grain size distribution or a monodisperse emulsion with a narrow grain size distribution.

In carrying out the present invention, it is preferable to use a monodisperse emulsion alone or a mixture thereof after sensitization.

In the present invention, a monodisperse silver halide emulsion is one in which the weight of silver halide contained within a grain size range of ±20% around the average grain size F is 60% or more of the weight of all silver halide grains. It is preferably 70% or more, still more preferably 80% or more.

Here, the average particle size F is the frequency n of particles having particle size ri
The product niX of i and rl3 is defined as the particle size ri when ri3 is the maximum (3 significant figures, the minimum digit is rounded down to 4 to 5).

In the case of spherical silver halide grains, the grain size ri is the diameter thereof, and in the case of grains having shapes other than spherical, it is the diameter when the projected image thereof is converted into a circular image of the same area.

The particle size can be obtained, for example, by photographing the particle with an electron microscope at a magnification of 10,000 to 50,000 times and measuring the particle diameter or projected area on the print.
(The number of particles to be measured shall be 1,000 or more indiscriminately.)

Particularly preferred highly monodisperse emulsions of the present invention have a distribution width of 20% or less, more preferably 15% or less, when the width of the distribution is defined as follows.

Here, the average particle diameter and standard deviation shall be determined from ri defined above.

A method for obtaining a monodisperse emulsion is to add a water-soluble silver salt solution and a water-soluble nitride solution to a gelatin solution containing seed particles.
It can be obtained by adding by double jet method under control of Ag and pH.

In determining the addition rate, reference may be made to JP-A-54-48521 and JP-A-58-49938.

As a method for obtaining a more advanced monodisperse emulsion,
The growth method in the presence of tetrazaindene disclosed in No. 122935 can be applied.

The silver halide emulsion of the present invention can be chemically sensitized by conventional methods.

The silver halide emulsion of the present invention can be optically sensitized to a desired wavelength range using dyes known as sensitizing dyes in the photographic industry. Sensitizing dyes may be used alone, but
You may use two or more types in combination.

Anticapri agents, stabilizers, etc. can be added to the silver halide emulsion. Gelatin is advantageously used as binder for the emulsion.

The emulsion layer and other hydrophilic colloid layers can be hardened or can be cured by containing a plasticizer or a dispersion (latex) of a water-insoluble or sparingly soluble synthetic polymer.

A coupler is used in the emulsion layer of a light-sensitive material for color photography.

Furthermore, by coupling with a colored coupler having a color correction effect, a competitive coupler, and an oxidized form of a developing agent, various 7-ragment products, namely, a development accelerator, a bleaching accelerator, a developer, a silver halide solvent, and a toning agent are produced. agent, hardener, fogging agent,
Compounds that release photographically useful fragments such as antifoggants, chemical sensitizers, spectral sensitizers, and desensitizers can be used.

The photosensitive material can be provided with auxiliary layers such as a filter layer, an antihalation layer, and an antiirradiation layer. These layers and/or the emulsion layer may contain dyes that are washed out or bleached from the light-sensitive material during the development process.

Photosensitive materials include formalin scavengers, optical brighteners,
A matting agent, a lubricant, an image stabilizer, a surfactant, a color antifoggant, a development accelerator, a development retarder, and a bleach accelerator can be added.

As a support, paper laminated with polyethylene, etc.
Polyethylene tele-7 tallate film, baryta paper, cellulose triacetate, etc. can be used.

To obtain a dye image using the photosensitive material of the present invention, after exposure,
Commonly known color photographic processing can be performed.

〔Example〕

Next, the present invention will be specifically explained with reference to Examples.

Here, the present invention will be specifically explained by preparing a core/shell type emulsion as one embodiment, but other embodiments (an emulsion having an average aspect ratio of 11/% silver halide grains, or It has been found that the effects of the present invention can also be obtained in an emulsion containing silver halide grains having three phases but not having a layered (core/shell) structure.

(Comparative Example 1) As comparative emulsions, core/shell type emulsions Em-1 and Em-2 were prepared according to the method of JP-A-61-245151.
was prepared.

The pAg during core growth was 8.7, and the pAg during shell growth was 10.2, and the pAg during intermediate shell growth was continuously changed.

(Comparative Example 2) Core/shell type emulsion E+I1-3 was prepared according to the method of JP-A-60-143331.

Prescription value (Example 1) Prepare a solution of 2.512 or less with water and prepare the fa/shell emulsion E■-4 of the present invention.
Prepare.

``Osei'Gelachi'' 25g Solution B-1 at 50°C was stirred at 1.000 revolutions/min using the stirring device shown in JP-A No. 62-160128. B-4 and solutions A-1 to A
-2 was added by the double jet method according to Table 3. In addition, pu and pAg at this time are shown in Table 3.
; It was controlled using a KBr aqueous solution and 56% acetic acid. *After the prescription value addition was completed, desalting and washing with water were performed in the usual manner.

Emulsion Em-4 was thus obtained.

(Comparative Example-3) Example! , a stirring device was developed in Japanese Patent Application Laid-Open No. 57-92523.
E-1 by the same procedure except that the equipment shown in
Prepare 5.

(Example 2) εm-6 was prepared in exactly the same manner as in Example-1 except that solution B-5 was used instead of solution B-4.

■Ossein gelatin 12g or less Margin or less 1 Table-5 (Example 3) Emulsion E+m-1"Em6 of Comparative Examples 1-5 and Examples 1-2
The silver iodide content of the core and the state of the silver iodide content after grain formation were investigated by X-ray diffraction. The results are shown in Table-6.

Moreover, the measurement results by X-ray diffraction method after particle formation of Em-4 are shown in FIG.

Table 6 (Emulsion E■-l- shown in Examples Comparative Examples 1-3 and Examples 1-2
E heavy-6 was chemically ripened in the presence of sodium thiosulfate, chloroauric acid and ammonium thiocyanate, divided and 4-hydroxy-6-methyl-1.3 was added with the sensitizing dye IV described later as a stabilizer. .3a. 7-Tetrazaindene was added. Using these emulsions, layers having the compositions shown below were sequentially formed on a triacetylcellulose film support from the support side to prepare a multilayer color photographic material.

Sample = (Reference) 1st layer: Antihalation layer (HC-2) Gelatin layer containing black colloidal silver.

2nd layer: Intermediate layer (I.L) gelatin layer.

3rd layer: Low sensitivity red-sensitive silver halide emulsion layer (RL-
2) A monodispersed emulsion (emulsion^) consisting of AgBrl containing 9 mol% of Ag with an average t diameter (r) of 0.80 μm and an Ag containing 8 mol% of Agl with an average grain size (r) of 0.4 μm.
Monodispersed emulsion (emulsion) consisting of Brl...coated silver amount 1.7 g/Shoulder 2 sensitizing dye I... 25X 10-' mol sensitizing dye ■... per 1 mol silver...
- 1.3X 10-' moles cyan coupler (C-1) for 1 mol of silver Colored cyan coupler (CC-1)... 0.08 mol for 1 mol of silver Colored cyan coupler (CC-1)... for 1 mol of silver 0.004 mol DIR compound CD-4)... 0-0005 mol per mol of silver 4th layer: Intermediate layer (I.L) Gelatin layer 5th layer: Low-sensitivity green-sensitive silver halide emulsion layer (GL-
2) Emulsion A...Amount of coated silver 1.79/I1'' Emulsion B Sensitizing dye ■... 1.9X 10-' mol sensitizing dye ■ per 1 mole of silver
... 1.9X 10-' mole magenta coupler (M-1) per 1 mole of l&1 mole Colored magenta coupler (CM-1): 0.06 mole of silver per mole of silver
0.012 mole to mole 6th layer: Intermediate layer (1.L) Gelatin layer 7th layer: Low-speed blue-sensitive silver halide emulsion layer (BI, -
2) Emulsion A...Amount of coated silver 1. Og/I12 sensitizing dye...
- 4.2X 10 moles per mole of silver Yellow coupler (Y-1)... 0.06 moles per mole of silver DIR compound (D-4)... per mole of silver 0.004 mol 8th layer: Intermediate layer (IL) Gelatin layer containing the emulsified dispersion of D-4 9th layer: High-sensitivity red-sensitive silver halide emulsion layer (RH-
2) Monodisperse (distribution 13%) silver iodobromide emulsion (E-1) - Coating film amount 2.1
9/II" sensitizing dye I... per 1 mole of silver!.3X 10-' mol sensitizing dye ■...
... 6.3X 101 molesian coupler (C-2) for 1 mole of silver... 0.015 molesian coupler (C-3) for 1 mole of silver... 0 for 1 mole of silver .015 mol Colored cyan coupler (CC-1): 20.002 mol per mol of silver DIR compound (D-4): 0.004 mol per mol of silver 10th layer: Intermediate layer (1.L) Eleventh layer of gelatin layer containing the emulsified compound of D-4: High-sensitivity green-sensitive silver halide emulsion layer (GH-
2) Monodisperse emulsion (Em-1)...coated silver amount 2.49 ha" Sensitizing dye re-... 7.OX 10-' mol sensitizing dye per 1 mol silver...
... 7.0 for 1 mole of silver. OX 10-'Magenta coupler (M-1)...0.020 mole per mole of silver Magenta coupler (CM-1)...0.002 mole per mole of silver 12th layer: Gelatin layer containing the emulsified fraction of D-4 13th layer: High-sensitivity blue-sensitive emulsion layer (BH-2'') Monodisperse emulsion (Em-1) ... Coated silver amount 2.19/m2 Sensitizing dye ■... 1.9X 10-' mole per mole of silver Yellow Kagura (Y-1)... 0.08 mole per mole of silver DIR compound (D-1)... - 0.0007 mol per mol of silver 14th layer: 1st protective layer (Pro-3) average grain f
M.O. 07tt mAgl 1 mol%AgBrl...
・Amount of coated silver 0.2 g/m" Gelatin layer containing ultraviolet absorbers UV-1, U'/-2 15th layer: Second protective layer (Pro-4) polymethyl methacrylate particles (diameter 1.5 μm) and Gelatin layer containing formalin scavenger (HS-1) In addition to the above composition, each layer also contains gelatin hardener (H-1).
(H-2.) and a surfactant were added.

The compounds contained in each layer of sample 1 are as follows.

Sensitizing dye I; Anhydro-5,5'-dichloro-9-ethyl-3,3'-di(3-sulfobyl)thiacarpocyanine hydroxide sensitizing dye ■; Anhydro-9-ethyl-3,3'-di (3-Sulhopkuchi Building)-4. 5. 4'. 5'
-diside sensitizing dye ■; anhydro 5,5'-d7enyl-9=
Ethyl-3,3'-di(3-sulfobropinole)oxacarpocyanine hydroxide sensitizing dye ■; Anhydro-9-ethyl-3,3'-di(3-sulfobropinole)-5. 6. 5'6'-
Dibenzooxalpocyanine hydroxide sensitizing dye V: Anhydro 3,3'-di(3-sulfopyl)-4,5-benzo5'-methoxythiacyanine anhydroxide C-1 0H C,H tapenzothiapyl Lupocyanine hydroxy C - C D-2 0H Below margin ゛, CC- l D-1 M-1 CM1 l Y-1 0H Cu 0H uv- i H-2 ((CI{2 = C) {SO2Cib) sccHzsO
z(CHz)z) zN(CHz)zsOdescriptionUV-2! fA-1 HS-1 H-1 Next, in Sample 1, silver halide emulsions Em-2 to Em- were used instead of Em-1 in the 9th layer, II layer, and 13th layer.
Samples 2 to 6 were prepared using No. 6.

Each sample No. prepared in this way. 1 to 6 were wedge exposed using white light, and then subjected to the following development treatment.

Processing process (38℃) Color development 3 minutes 15 seconds bleaching
Wash with water for 6 minutes and 30 seconds, set for 3 minutes and 15 seconds 1i
Wash with water for 6 minutes and 30 seconds
Stabilized for 3 minutes and 15 seconds
Drying for 1 minute and 30 seconds The composition of the treatment liquid used in each treatment step is as follows.

[Color developer]

4-Amino-3-methyl-N-ethyl-N-(β-hydroxyethyl)monoaniline sulfate 4.75g Anhydrous sodium sulfite 4.25g Hydroxylamine 1/2 sulfate 2.0g Anhydrous potassium carbonate 37.5g Sodium bromide
1.3g nitrilotriacetic acid trisodium salt (l hydrate) 2.5g potassium hydroxide l. Add Og water to make la.

[Bleach solution]

Ethylenediaminetetraacetic acid iron ammonium salt 100g Ethylenediaminetetraacetic acid diammonium salt 10.0g Ammonium bromide 150.0g Glacial acetic acid 10.0m (2 Add water to make IQ, use aqueous ammonia to pH = 6.0
Adjust to.

[Fixer]

Ammonium thiosulfate 175.0g Anhydrous sodium sulfite 8.5g Sodium metasulfite 2.3g Add water to make 1f2, and adjust to pH=6.0 using acetic acid.

[Stabilizing liquid]

Formalin (37% aqueous solution) 1.
511Q Conidax (manufactured by Konishiroku Photo Industry Co., Ltd.) 7
．． Add 5mQ water to make IQ.

Relative sensitivity (S) and granularity (R M S ) of each sample obtained were measured using blue light (B), green light CG'), and red light (R). Table 7 shows the results when green light was used.

Note that the relative sensitivity (S) is a relative value of the reciprocal of the exposure amount that gives a fog density of +0.1, and is a relative value of the reciprocal of the exposure amount that gives a fog density of +0.1. 4 W sensitivity to 1
It is shown as a value of 00.

The RMS value is the density of the minimum density + 0.3 with an aperture scanning area of 25
It is expressed as a relative value of the standard deviation of density value fluctuations that occur when scanning with a 0 μi microdensitometer.

The smaller the RMS value, the more effective it is.

Table-7 The results were obtained.

Furthermore, the effects of the present invention were also obtained in the case where the monodisperse emulsion of E++-4 was replaced with a polydisperse emulsion with a coefficient of variation of 23%.

Further, preparing an emulsion having three diffraction peaks and having a minimum diffraction intensity of 93% sandwiched between the two adjacent diffraction peaks with respect to the weaker one; Sensitivity and granularity were measured in the same manner as in Example 4, and the effects of the present invention were observed.

[Brief explanation of the drawing]

FIG. 1 shows the X-ray diffraction pattern of emulsion grains, where the horizontal axis represents the diffraction angle (2θ) and the vertical axis represents the diffraction intensity. Applicant: Roku Konishi Photo Industry Co., Ltd. As can be seen from Table 7, sample No. 1 using the silver halide emulsion of the present invention. It can be seen that samples 4 and 6 are excellent in both sensitivity and granularity.

Claims (1)

[Claims] A silver halide emulsion containing silver iodobromide grains having three or more phases of different compositions of silver bromide or silver iodobromide, in which the highest iodine phase is detected in the diffraction signal by powder X-ray diffraction. , a diffraction peak corresponding to the lowest iodide phase, and three diffraction peaks corresponding to one or more iodide phases having a composition intermediate between the highest iodide phase and the lowest iodide phase. A silver halide photographic light-sensitive material characterized by having at least one emulsion layer containing an emulsion having the above diffraction maximum and two or more diffraction minima therebetween.