JPH0412344A - Silver halide photographic sensitive material and preparation thereof - Google Patents

Abstract

PURPOSE:To improve reproducibility, sensitivity and preservable property by adding a spectral sensitizing dye to an emulsion by taking the time for distributing and adding the prescribed ratio of this dye longer than the average mixing time at the time of prepn. of the emulsion, thereby eliminating the fluctuation in function among the emulsion particles and lessening the change in performance in an emulsion state. CONSTITUTION:The above-mentioned dye is added to the emulsion by taking the time Ta for distributing and adding the dye longer than the average mixing time T for mixing and stirring the emulsion. The time T to attain the uniform distribution in the liquid mixture phase is basically given by the average mixing time of the liquid mixture phase of the emulsion. The time Ta for distributing and adding the dye suffices, insofar as this time is longer than the average mixing time for stirring. The preferable time is >=1 minute, and further the more preferable time is >=5 minutes. The change in the desorption of the sensitizing dye from the silver halide particles or the adsorption state thereof at the time of the prepn. of the emulsion or the preservation of the photosensitive material is decreased in this way and the production stability preservable property and sensitivity are improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a silver halide photographic light-sensitive material and a method for preparing a silver halide emulsion used in the construction of the light-sensitive material.

[Background of the invention]

In the process of preparing silver halide photographic emulsions (hereinafter simply referred to as emulsions), various additives are added to the emulsion mother liquor in order to adjust and improve photographic properties and impart specific properties. Finished in a beautiful emulsion.

As is well known, an emulsion is a suspension of silver halide (designated as AgX) crystal grains in a hydrophilic polymer solution, generally a gelatin solution.

The basic properties required of a silver halide photographic material composed of such an emulsion are high sensitivity, low fog, high development activity, and excellent storage stability of the material.

In order to increase the sensitivity of a photosensitive material, it is required to increase the sensitivity of silver halide grains, which are the basic elements forming the photosensitive layer of the photosensitive material, and various chemical sensitization methods have been studied. Typical methods thereof include sulfur sensitization, selenium sensitization, noble metal sensitization, reduction sensitization, and sensitization by combinations thereof.

Furthermore, various studies have been made on methods for increasing the sensitivity of silver halide grains themselves. Regarding specific light absorption, it increases in the order of AgC4, AgBr, and Ag+.
On the other hand, development activity decreases in the above order. As a way to reconcile these contradictory characteristics,
No. 939 discloses a silver halide core inside the grain and a core/core covered with a different silver halide shell layer.
Shell-type silver halide emulsions are disclosed to separately bring out the useful properties of each silver halide. In particular, as a method for sensitizing by increasing light absorption and maintaining good processability, an example of increasing the Agl content in the inner core and giving a particle structure having a single layer of AgBr with a relatively low Agl content as a shell is as follows. JP-A-60-14331, JP-A No. 61-
It is disclosed in No. 245151. In the case of photographic paper and printing sensitive materials that require higher processing properties, they have a core with a high silver bromide content inside and cover it with a layer with a lower silver bromide content. Examples of AgBrC12 particles are described in Japanese Patent Publication No. 56-18939 and Japanese Patent Application Laid-open No. 61-215540.

These AgBr, AgBr1. The characteristic absorption edge of silver halides such as AgBr(J) is in the blue to ultraviolet light region and absorbs only a portion of visible light. So-called spectral sensitization is carried out by adsorbing a dye.Generally, if the adsorption of the dye to silver halide is weak, the dye may desorb from the silver halide grains during storage of the light-sensitive material, or the adsorption state may deteriorate. changes in photographic performance.Especially when placed under high temperature and high humidity, the change is large.In color photosensitive materials, spectral sensitizing dyes in certain color-sensitive layers may diffuse to other color sensitivities, causing significant performance deterioration such as color turbidity.

The adsorption of spectral sensitizing dyes to silver halide is often stronger in the order of silver chloride, silver bromide, and silver iodide, but based on this tendency, the adsorption of spectral sensitizing dyes to silver halide becomes stronger in the order of silver chloride, silver bromide, and silver iodide. This is disadvantageous, and is also mentioned in Japanese Patent Application Laid-open No. 1-273033 as an essential weakness of double-structured particles as disclosed in Japanese Patent Application Laid-Open No. 60-14331.

On the other hand, attempts have been made to enhance adsorption by selecting the addition position of the spectral sensitizing dye, and US Patent No. 2,735.766
No. 3,628.960, No. 4,183.756, No. 4,225.666, JP-A-55-26589, and JP-A No. 58-184142 show that during particle formation (during physical ripening) Addition techniques are shown.

However, although this method improves the amount of dye adsorption and its retention under various environments, it has the problem that the dye adsorbs to the surface of the growing particles, interfering with normal crystal growth. .

JP-A-61-103149 and JP-A No. 61-196238 disclose a technique in which it is added in the latter half of grain growth so that the particle shape does not substantially change, and from after grain formation to before the desalting process. , JP-A-1-52137 discloses a technique for adding it during the desalting process. In these techniques, adsorption is certainly enhanced compared to when the additive is added after the desalting process and before the coating process, but they do not provide a sufficient level of improvement.

Moreover, it is disadvantageous in terms of production efficiency.

Furthermore, as a method for strengthening adsorption on the side of silver halide grains, Japanese Patent Application Laid-Open No. 106745/1983 describes a method in which the surface Agl content of core/shell structure grains with an internal high Agl content is increased to 5 moQ.
% or more. However, it is well known that as the surface Agl content increases, the suitability for chemical sensitization deteriorates, resulting in a decrease in sensitivity and a decrease in development activity. It is difficult to be satisfied. - Also, the publication does not mention any specific method to solve this problem. JP-A-1-273033 discloses a technique for improving the suitability for chemical sensitization by changing a part of the surface of the same surface index of particles with a high Agl content to a different composition, that is, a low Agl content. Disclosed. However, particles having such a structure have the drawback of poor production stability and storage stability.

In addition to the above-mentioned macroscopic problem of equilibrium, there are further problems of reaction kinetics and microscopic uniformity and homogeneity of reaction or adsorption based on emulsion grains.

When these additives are added as a solution, suspension, or powder to the emulsion mother liquor (the emulsion solution that is in the process of forming the final finished photographic emulsion to be coated), they can be added quickly or gradually, depending on the stirring conditions. It is evenly distributed throughout the entire mother liquor, reaching a homogeneous distribution after 1 hour from the time of addition.

However, during the period from said addition to uniform distribution within said mixed liquid phase, uniform distribution over the entire mother liquor is slow, and dissolution is fast and adsorption rate is high and/or relatively small amounts of silver halide are added. If there are many adsorption sites, the additive will be taken up only in the emulsion grains near the addition point, and adsorption will be completed.If several types of such additives are used, each emulsion grain will be adsorbed individually. Different additives and amounts constitute various miscellaneous particle groups with different photographic behaviors, and if these additives are added at different times, the desorption equilibrium due to competitive adsorption with the preceding adsorption additive may be affected. Furthermore, problems of irreversible adsorption and selective adsorption of additives to crystal phase planes are intertwined, and the emulsion design and control means to fully utilize the qualities of the emulsion grains become uncontrollable.

Moreover, when it is necessary to use an emulsion consisting of a group of grains with different crystal phases and/or grain sizes instead of a monodisperse emulsion, the above-mentioned inconsistency is doubled, and the reliability as a technical system becomes extremely low. .

Therefore, if we want reproducible photographic properties in emulsions, we have no choice but to wait for the adsorption equilibrium of all additives, but the emulsion preparation time is too short to wait for equilibrium, and on the other hand, The transition to adsorption equilibrium under these conditions progresses gradually but surely, leading to changes in performance over time.

[Purpose of the invention]

The object of the present invention is to provide the above-mentioned additives between emulsion grains,
In particular, in addition to the equilibrium problem of spectral sensitizing dyes, we focused on the necessity of microscopic homogeneous adsorption. (2) There is no variation in functionality between emulsion grains, (3) There is little change in performance in the emulsion state and there is good reproducibility, (4) A method for preparing an emulsion with high sensitivity and good storage stability, and The object of the present invention is to provide a photosensitive material having the above characteristics.

[Structure of the invention]

The object of the present invention is to perform spectral sensitization on the emulsion mother liquor by adding a silver halide solvent to the emulsion mother liquor in which emulsion grain formation of a silver halide photographic emulsion has been completed, and then distributing and adding a predetermined amount of a spectral sensitizing dye. A silver halide characterized in that the predetermined amount of the spectral sensitizing dye is added for a longer time than the average mixing time during the preparation of the emulsion in the process or in the process including a process of chemical sensitization. A method for preparing a photographic emulsion, and a photographic light-sensitive material having at least one silver halide photographic emulsion layer on a support, in which at least one of the silver halide emulsion layers is coated with the method for preparing a silver halide photographic emulsion. This is achieved by a silver halide photographic material containing the prepared silver halide photographic emulsion.

Time T during which uniform distribution within the mixed liquid phase according to the invention can be reached
is basically given by the average mixing time of the emulsion mixture liquid phase. The average mixing time here is the time required for the concentration in the mixed liquid phase to reach 95% of the equilibrium concentration after addition of the additive substance.

In the present invention, the distributed addition time Ta satisfies Ta≧T.

Further, the upper limit of Ta may be determined by taking into account the number of dyes used, the necessary addition time, the allowable process time, etc.

Regarding the addition method of the dye, the number of nozzles used for addition may be one or more, and the position of the outlet for the liquid from the nozzle may be above the liquid surface or immersed in the mother liquor.

Further, the addition rate during the distributed addition time Ta may be constant throughout, may be given a smooth or step-like increase/decrease change, or may be added in portions.

The emulsion mother liquor according to the present invention has different liquid properties such as gelatin concentration, AgX particle content, particle size or viscosity, and temperature depending on its formulation.When adding a dye to the emulsion mother liquor, the liquid of each emulsion mother liquor It is necessary to determine stirring and mixing conditions according to the characteristics.

At this time, the flow behavior of the emulsion mother liquor differs depending on whether it is a circulating flow throughout the mother liquor or a turbulent flow of local swirling flow, so the flow behavior of the mother liquor is used as a stirring system. It is necessary to capture it.

In other words, it is of course necessary to provide circulating flow or convection to quickly homogenize the mother liquor, but the microscopic mixing behavior is also important because the target is one ls of suspended solids such as AgX particles. When influencing the reaction mechanism and reaction amount, it is necessary to pay attention to the strength and scale of turbulence.

The flow behavior of such emulsion mother liquor, like general low-viscosity fluids, is related to the stirring Reynolds number Re -p d''n/η, and is correlated with various properties such as the required stirring power and heat transfer characteristics.

In the stirring tank used as a reaction tank for promoting and homogenizing the reaction of the dye, it is necessary to select the flow behavior of the emulsion mother liquor, which is determined by the stirring conditions, depending on the reaction characteristics of the dye.

On the other hand, the liquid characteristics of the emulsion mother liquor and the required power P for stirring involving a stirring mechanism such as a pump are related to the power number Np defined as Np = P /p n"d', and furthermore, the power number Np is N1
)=A/Re (A is a constant) and is related to the stirring Reynolds number.

When Re exceeds several thousand, a clear turbulent flow appears after passing through the turbulent flow transition region, and a circulation flow spreads throughout the mother liquor, but when Re
Below several hundred, the part away from the stirring blade forms a laminar flow, and further down, the flow stops only in the vicinity of the stirring blade.

In a sufficiently developed turbulent region where Re is large, Np becomes a substantially constant value Npω.

In the present invention, the flow conditions of the emulsion liquid are adjusted to 1 J when adding the dye.
Preferably, this is done in the poo area.

In this area, rapid and uniform distribution of the dye into the mother liquor is realized, which improves characteristic reproducibility not only in the case of the same scale preparation but also in the case of different scales, as well as guaranteeing homogeneity in continuous preparation. A step is given.

Note that ρ is the emulsion mother liquor density, l is the viscosity, n is the rotation speed of the stirring blade, and d is its diameter.

The present invention will be explained in more detail below.

In the present invention, "emulsion grain formation has been completed" means a situation in which 100% of the silver salt and halide necessary to produce a predetermined amount of AgX crystals have been added to the mother liquor.

Next, the order of addition of AgX solvent, dye and chemical sensitizer is A
The gX solvent is added first, preferably after the desalting step and before the AgX crystal surface is subjected to dye adsorption or chemical sensitization effects.

The dye is added at least after the addition of the AgX solvent, and the addition interval depends on the type of AgX solvent and the temperature and pH of the mother liquor.

Although it depends on conditions such as pAg, in practice it is 1 minute or more, more preferably 5 minutes or more.

However, it is essential that the silver halide solvent is added before the spectral sensitizing dye, and after adding the dye,
For example, it may be added together with a gold sensitizer.

The distribution addition time Ta of the dye may be longer than the average mixing time of stirring, preferably 1 minute or longer, more preferably 5 minutes or longer.
It's more than a minute.

The chemical sensitizer is added at the same time as the AgX solvent is added, more preferably after the dye is added, and in practice it is 5 minutes, more preferably 15 minutes after the dye distribution addition time Ta has elapsed. be.

Next, in the present invention, the AgX solvent added prior to addition of the dye will be described. As the solvent, AgX
Although various AgX solvents having the action of dissolving AgX may be used, the AgX solvent preferably used in the present invention includes (a)
U.S. Patent No. 3,271,157, U.S. Patent No. 3,531.289
Organic thioethers described in JP-A No. 3,574.628, JP-A-54-1019, JP-A-54-158917 and JP-A-62-14646, etc.;
No. 82408, No. 55-77737 and No. 55-29
Thiourea derivatives described in No. 829 etc., (C) Ag having a thiocarponyl group sandwiched between an oxygen or sulfur atom and a nitrogen atom described in JP-A-53-144319
X solvent, (d) imidazoles described in JP-A-54100717, (e) sulfites, (f) thiocyanates, (g) hydroxyalkyl-substituted ethylenediamines described in JP-A-57-196228, (h)
Examples include substituted mercaptotetrazoles described in JP-A-57-202531.

Next, specific examples of the AgX solvents (a) to (h) will be given. However, the AgX solvent that can be used in the present invention is not limited to the following examples.

(a) HO(CH2)z (CH2)2 CH2NHCO-CHzCHzCOOHCH2-5-C
H, CH25C2H3 CH, -NHCO-CH, CH2CH2CHz S
CH2CHxSCHxCH*C00H(cnJz
on (C) (b) (d) (e) (f) NH. SCN K, So.

SCN (g) H-3 H H H H (h) In the preparation method of the present invention, the amount of AgX solvent added is arbitrarily determined depending on the desired effect, but is 0.0005 to 1 per mole of AgX. It is preferable that it is .0g,
More preferably, it is 0.001 to 0.5 g, particularly preferably o, oos to 0.2 g.

Spectral sensitizing dyes used in the present invention include methine dyes, cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, hemioxonol dyes, and the like. Ru. Particularly useful dyes are those belonging to the cyanine dyes, merocyanine dyes, and complex merocyanine dyes. Any of the nuclei commonly used for cyanine dyes can be used as the basic heterocyclic nucleus for these dyes.

That is, pyrroline nucleus, oxazoline nucleus, thiazoline nucleus, pyrrole nucleus, oxazole nucleus, thiazole nucleus, selenazole nucleus, imidazole nucleus, tetrazole nucleus, pyridine nucleus, etc.; a nucleus in which an alicyclic hydrocarbon ring is fused to these nuclei; and these A nucleus in which an aromatic hydrocarbon ring is fused to the nucleus of Imidazole nuclei, quinoline nuclei, etc. can be applied. These nuclei may be substituted on carbon atoms. Merocyanine dyes or composite merocyanine dyes include a pyrazolin-5-one nucleus, a pyrazolin-5-one nucleus, and a ketomethylene structure.
Thiohydantoin core, 2-thioxazolidine-2,4
A 5- to 6-membered heterocyclic nucleus such as a dione nucleus, a thiazolidine-2,4-dione nucleus, a rhodanine nucleus, a thiobarbic acid nucleus, etc. can be applied.

Useful sensitizing dyes include, for example, German Patent No. 929.
No. 080, U.S. Patent No. 2,231,658, U.S. Patent No. 4,04
6,572, British Patent No. 1,242,588, Japanese Patent Publication No. 44-14030, Japanese Patent Publication No. 52-24844, and the like.

These sensitizing dyes may be used alone or in combination, and combinations of sensitizing dyes are often used particularly for the purpose of supersensitization.

Typical examples are U.S. Pat. No. 2,688.545 and U.S. Pat.
No. 26,707, British Patent No. 1,344.281, No. 1
．． No. 507,803, Special Publication No. 43-4936, No. 53
-12375, JP-A-52-110618, JP-A No. 52
-409925 etc.

Along with the sensitizing dye, the emulsion may contain a dye that itself does not have a spectral sensitizing effect or a substance that does not substantially absorb visible light and exhibits supersensitization.

These sensitizing dyes may be added after being dissolved in water or an organic solvent miscible with water such as methanol or ethanol, or if they are water-insoluble, they may be added with a surfactant. It may be solubilized and added as a solution.

Alternatively, a dispersion in water may be formed and added.

The amount of the spectral sensitizing dye added in the present invention is not particularly limited, but preferably the total amount added is l x 1 per mole of silver.
0-' to l x 10-' mol.

Any chemical sensitizer can be used as the chemical sensitizer according to the present invention, but unstable chalcogen compounds are used,
Alternatively, it is preferable to use an unstable chalcogen compound and an unstable metal compound in combination.

As the chalcogen compound, a sulfur compound or a selenium compound is preferably used.

As the metal compound, gold, platinum, palladium, iridium, and rhodium compounds are preferably used.

A particularly preferred means of chemical sensitization when carrying out the present invention is the combined use of sulfur sensitization and/or gold sensitization. Thereby, a remarkable sensitizing effect can be obtained. Among the above, the combined use of sulfur sensitization and gold sensitization is particularly useful since it not only provides a sensitizing effect but also a fog suppressing effect.

Various sulfur sensitizers can be used for the above-mentioned sulfur sensitization. Examples include thiosulfate, allylthiocarbamide thiourea, allyl isothiacyanate, cystine, I)-toluenethiosulfonate, and rhodanine. Other patents include US Pat. No. 1,574,944, US Pat. No. 3,656.955, and German Patent I.

Sulfur sensitizers described in Japanese Patent Publication No. 422.869, Japanese Patent Publication No. 56-24937, Japanese Patent Application Laid-Open No. 55-45016, etc. can also be used. The amount of sulfur sensitizer added may be sufficient to effectively increase the sensitivity of the emulsion. This amount is p
Although it varies over a considerable range under various conditions such as H, temperature, and the size of AgX particles, as a guide, AgX
About 1 O-7 to about 1 O-1 mole per mole is preferred.

As the gold sensitizer for the above gold sensitization, the oxidation number of gold may be +1 or +3, and gold compounds commonly used as gold sensitizers can be used. Typical examples include chlorauric acid salt, potassium chlorate, auric trichloride, potassium auric thiocyanate, potassium iodoaurate, tetracyanoauric acid,
Examples include ammonium aurothionanate and pyridyl trichlorogold.

The amount of gold sensitizer added also varies depending on various conditions, but as a guideline it is approximately 10-7 mol per 1 mol of AgX.
Ranges up to 10-' moles are preferred.

In the preparation method of the present invention, the temperature of chemical ripening is arbitrary as long as the desired sensitization is achieved, but it is preferably 90 ° C to 20 ° C, more preferably 80 ° C to 30 ° C, Particularly preferably the temperature is 70°C to 35°C.

The composition of AgX particles in the emulsion according to the present invention is arbitrary,
For example, AgCl2Brl, AgCQ, AgC(lB
r, AgBr.

Any silver halide such as AgBr I may be used. The average grain size of the silver halide grains is preferably 0.1 to 8.0 μm, more preferably 0.2 to 3.0 μm, and particularly 0.1 to 8.0 μm, more preferably 0.2 to 3.0 μm.
．． The effect of the present invention is great for particles of 6 to 3.0 μm. The internal structure of the silver halide grains is arbitrary, but preferably has a multilayer structure as described in JP-A No. 61-245151. The shape of the silver halide grains may be regular crystal shapes (normal crystals) such as hexahedron, octahedron, dodecahedron, or tetradecahedron, or irregular crystal shapes such as spherical or tabular. It can be anything. or,
Regarding the grain size distribution of the silver halide grains, the emulsion may have a wide size distribution or a narrow so-called "monodisperse" emulsion.

Here, monodisperse means the coefficient of variation of the particle size of AgX particles, that is, the coefficient of variation (U) = standard deviation / average particle diameter x 100 (%)
When the width of the distribution is defined by, U of AgX particles is 2
It means having U of 0% or less, more preferably 15% or less.

In addition, the above-mentioned average grain size refers to the diameter in the case of spherical silver halide grains, and in the case of grains having shapes other than cubic or spherical, the diameter when the projected image is converted to a circular image of the same area. As an average value, when the individual particle size is ri and the number is ni, r is defined by the following formula.

r = Σn1ri/Σni In addition, in the process of forming AgX particles according to the present invention, for example, cadmium salt, zinc salt, lead salt, iron salt, thallium salt, iridium salt or a complex salt thereof, rhodium salt, osmium salt, ruthenium salt or A complex salt thereof may also be present.

Further, when carrying out the present invention, antifoggants, stabilizers, etc. can be added to the silver halide emulsion. Gelatin is advantageously used as binder for the emulsion.

When obtaining a light-sensitive material using the emulsion prepared according to the present invention, the emulsion layer and other hydrophilic colloid layers can be hardened, and a dispersion (latex) of a plasticizer, a water-insoluble or poorly soluble synthetic polymer can be used. ) can be included.

When embodied as a light-sensitive material for color photography, a coupler is used in the emulsion layer.

Furthermore, a colored coupler having the effect of color correction, a competitive coupler, and an accelerator that accelerates development by coupling with an oxidized form of a developing agent, a bleach accelerator, a developer, and Ag.
Compounds that release photographically useful fragments such as X-solvents, toning agents, hardeners, fogging agents, antifogging agents, chemical sensitizers, spectral sensitizers, and desensitizers can be used.

Further, such a 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.

Furthermore, formalin scavengers, optical brighteners, matting agents, lubricants, image stabilizers, surfactants, color cast inhibitors, development accelerators, development retarders and bleaching accelerators can be added to the photosensitive materials.

As the support for the photosensitive material, paper laminated with polyethylene or the like, polyethylene terephthalate film, baryta paper, cellulose triacetate, etc. can be used.

In order to obtain a dye image using a light-sensitive material using the emulsion obtained according to the present invention, commonly known photographic processing may be performed after exposure.

〔Example〕

The present invention will be further explained below with reference to Examples, but the present invention is not limited thereto.

Example 1 Using the 8 types of solutions shown below, 15
Cores with Agl content of mol%, 5 mol% and 3 mol%/
A shell-type silver iodobromide emulsion EM-1 having an average grain size of 0.81 μm and an average Agl content of 7.16 mol % was prepared.

(Solution A-1) Ossein gelatin IO, 8g propanone (10% ethanol solution) 20.0mQ4
-Hydroxy-6-methyl-1,3,3a,7tetraazaindene (hereinafter referred to as TA+) 200mg
56% acetic acid aqueous solution 32.5ml
228% ammonia aqueous solution 58.7mQ
Seed emulsion (silver iodobromide with Ag+ content of 2 mol%, average grain size 0.33 um.

Coefficient of variation 26%) Agl Adjust to 4000 mα with distilled water.

(Solution B-1) ossein gelatin Br old TA+ Bring to 1300 mff with distilled water.

(Solution C-1) ossein gelatin Br I AI Make the volume up to 1700m12 with distilled water.

(Solution D-1) ossein gelatin Br old AI Make up to 800ml (l) with distilled water.

0.4673 mole equivalent 0g 404.6g 99.6g 224mg 0g 791.4g 58.1g 142mg 5g 606.0g 26.15g 605mg (Solution E-1) AgNOs
310-4g 28% ammonia water
253+++12 Make 1827m12 with distilled water.

(Solution F-1) AgNO3” 803.3g 28% ammonia water 655mQ Make up to 1351ml with distilled water.

(Solution G-1) 20% KBr solution pAg adjustment required amount (
Solution H-1) 56% acetic acid aqueous solution pH adjustment required amount 40°
In C, JP-A-57-92523, JP-A-57-92
! Using the same mixer as shown in No. 524, solution E-1 and solution B-1 were added to solution A-1 by the simultaneous mixing method, and at the same time as the addition of B-1 was completed, C-1 and F −
1 was added, and D-1 was added at the same time as the addition of C-1 was completed. Control of p7kg, pi (and solution E during simultaneous mixing)
-1. Solution B-1, solution C-1 and solution D-1, F-1
The addition rate was as shown in Table 1.

pAg and pH were controlled by changing the flow rates of solution G-1 and solution G-1 using a roller tube pump with variable flow rate.

Table 1 Particle growth conditions Next, wash with demineralized water using a conventional method, and ossein gelatin 19
After dispersing 7.4g in an aqueous solution, the total amount was made up to 30g with distilled water.
It was adjusted to 00m12. At this time, at 40°C, the pH
6.00, pAg was adjusted to 7.7.

Next, by the method shown below, emulsions EIA-2, EM3,
EM-4 and emulsions EM-5 and EM-6 of the present invention were prepared.

(Preparation of comparative emulsion EM-2) Emulsion EM-1 in an amount equivalent to 1 mole of silver halide was mixed and stirred at 50°C for an average mixing time of about 15 seconds.
Add 68cc of the spectral sensitizing dye solution shown below instantly (approximately 2 seconds or less), and after 30 minutes add 6.5X sodium thiosulfate.
Added 10-6 mol of chlorauric acid 2X after another 2 minutes.
10-' mol, ammonium thiocyanate 6.0 x 1O
−4 moles, making a total amount of 7 moles per mole of silver halide.
Adjusted to 00cc.

4- as a stabilizer at the time when the sensitivity-fogging relationship is optimal.
Hydroxy-6-methyl-1,3,3a,7-chitrazaindene was added and at the same time the temperature was lowered to 40°C to stop chemical ripening. The time giving optimal sensitivity was 130 minutes after addition of sodium thiosulfate.

Furthermore, a magenta coupler dispersion represented by M-1 below was added to obtain emulsion EM-2. After that, one part of the emulsion was separated to make the total amount 4000 cc per mole of silver halide,
Stirring was continued at 40°C, the reflection spectrum of the emulsion solution was measured, and the change over time in the sensitizing dye adsorption state was measured.

Further, one part of the emulsion was taken out, a hardening agent was added thereto, and the emulsion was coated on a cellulose triacetate film support and dried to obtain coated samples No. 1.

(Preparation of comparative emulsion EM-3) 15 minutes before adding the sensitizing dye solution, 5.5X 10-' mol of ammonium thiocyanate was added, and the amount of ammonium thiocyanate added at the same time as chloroauric acid was increased to 0.5X.
Emulsion EM-3 was prepared in exactly the same manner as EM-2 except that the emulsion was changed to 10-' mol, and coating sample No. 12 was obtained.

(Preparation of comparative emulsion EM-4) In the preparation of emulsion EM-2, the sensitizing dye solution was added at a constant flow rate over 20 minutes, and sodium thiosulfate was added 30 minutes after the dye solution addition path=34. Emulsion EM-3 was prepared in exactly the same manner as EM-2 except for the above, and coating sample No. 003 was obtained.

(Preparation of sample EM-5 of the present invention) Sodium thiosulfate was added to emulsion EM-1, and
After 10 minutes, chloroauric acid and ammonium thiocyanate were added, and after another 10 minutes, the addition of the sensitizing dye solution was started (addition over 20 minutes at a constant flow rate). 5 and coating sample No. 4 were obtained.

(Preparation of emulsion EM-6 of the present invention) In the preparation of emulsion EM-4, 5.5 x 1 O-4 ammonium thiocyanate was added 15 minutes before adding the sensitizing dye solution.
Emulsion EM-6 was prepared in exactly the same manner, except that the amount of ammonium thiocyanate added at the same time as chloroauric acid was changed to 0.5×10-' mol, and coating sample N005 was obtained.

As an indicator of stability during emulsion preparation, the change in the shape of the reflection spectrum in the spectral sensitization region when stirring the emulsion at 40°C (
That is, the change in the state of dye adsorption from the time when chemical ripening was stopped was evaluated. The measurement was performed using a spectrophotometer Uv-2100 equipped with an integrating sphere manufactured by Takasu Seisakusho Co., Ltd. Example of change in reflection spectrum shape over time of stirring (EM-2)
is shown in FIG. 1 (reflectance is converted into absorbance and shown). It can be seen that the dye gradually desorbs and the absorbance decreases.

Table 2 shows the rate of decrease in absorbance after 3 hours of stirring with respect to the absorbance at a wavelength of 560 nm immediately after preparation. It can be seen that the emulsion of the present invention has a small reduction rate and is excellent in stability during emulsion preparation.

Sensitizing dye solution Sensitizing dye S -12,7x 10-'mol//S
-21,9X IQ-4mo/l.

HCF* CFx CH*OH20ccCHsOH
Using 80cc coating sample No. 1 = No. 5, emulsion E
Sensitivity and storage stability of M-, 2 to EM-6 were evaluated.

After each coated sample was exposed to wedge light through a green light filter, the following development treatment was performed.

Development process (38°C) Color development 2 minutes 50 seconds Bleaching 6 minutes 30 seconds Water
Wash for 3 minutes and 15 seconds
Arrive: Wash for 6 minutes and 30 seconds
Stabilized for 3 minutes and 15 seconds. Dry for 1 minute and 30 seconds. The composition of the drying solution is as follows.

(Color developer) 4-amino-3-methyl-N-ethyl-N-(β-hydroxyethyl)-aniline, sulfate, anhydrous sodium sulfite, hydroxylamine, 1/2 sulfate, anhydrous potassium carbonate, sodium bromide, nitrilotriacetic acid, Trisodium salt (l hydrate salt) Add potassium hydroxide water to make IQ.

(bleach solution) Iron ethylenediaminetetraacetate ammonium salt Ethylenediaminetetraacetic acid 2 ammonium salt ammonium bromide glacial acetic acid Add water to make if, Adjust the pH to 6.0.

(Fixer) 10.0g 150.0g 10.0m12 Using ammonia water, 4.75g 4.25g 2.0g 37.5g 1.3g 2.5g 1.0g 100.0g γ Ammonium thiosulfate 175.0g anhydrous Sodium sulfite 8.5g Thorium metasulfite 2.3g Add water to 1Q
, and adjusted to pH 6.0 using acetic acid.

(Stabilizer) Formalin (37% aqueous solution) 1.5mf
f Konidax (manufactured by Konica Corporation) 7.5mQ
Add water to make 1Q.

The sensitivity is determined by taking the reciprocal of the exposure amount that gives a density of fog +0.3, and Table 2 shows the relative value when the sensitivity of sample No. 1 is taken as 100.

The storage stability of the coated sample is to store the sample at 40°C1 relative humidity 80°C.
Sensitivity when left for 7 days under conditions of % and wavelength 56
The absorbance of the coated sample at 0 nm was compared with that immediately after sample preparation to evaluate the fluctuation. Table 2 shows the results.

Table 2 shows that the emulsions Em-5 and Em-6 of the present invention and the light-sensitive materials using them are excellent in storage stability in terms of both sensitivity and dye adsorption properties.

In addition, Em-6 has better performance than Em-51, and adding a sensitizing dye before adding a chemical sensitizer can give more favorable results in terms of high sensitivity. Recognize.

Example 2 A multilayer color photosensitive material having the composition shown below was prepared on a subbed triacetylcellulose film support. Sample No. 1 was prepared using emulsion Em-2 of Example 1, with the eighth layer (high sensitivity green-sensitive emulsion layer) being a silver iodobromide emulsion.
6 (comparative sample), sample using the same emulsion Em3, No. 7
(comparative sample), and a sample using the same emulsion Em-6 is designated as No. 8 (present invention).

The coating amount is the amount expressed in g/m'' in terms of silver for silver halide and colloidal silver, the amount expressed in g/m'' for additives and gelatin, and the amount expressed in g/m'' for sensitizing dyes. , couplers, and DIR compounds are expressed as the number of moils per mo12 of silver halide in the same layer.

The emulsion contained in each color-sensitive emulsion layer was optimally sensitized using sodium thiosulfate and chloroauric acid.

1st layer: Antihalation layer (HC-1) Black colloidal silver 0.20 Ultraviolet absorber (UV
-1) 0.20 High boiling point solvent (oil -1) 0.20 Gelatin 1.5 2nd layer: Intermediate layer (+, L, -1) Ultraviolet absorber (UV-1) High boiling point solvent (0th - 1) Third layer of gelatin: low-sensitivity red-sensitive emulsion layer (RL) Silver iodobromide emulsion (emulsion A below) Silver iodobromide emulsion (emulsion B below) Sensitizing dye■ Sensitizing dye■ Sensitizing dye V Cyan coupler (C-1) Cyan coupler (C-2) Colored cyan coupler (CC-L DIR compound (D-1) High boiling point solvent (oil-1) Gelatin 4th layer: High sensitivity red-sensitive emulsion layer (RH) 0, Ol 0.01 1.5 0.9 0.6 2.5X 10-' 2.5X 10-' 0.5X 10-' 1.0 0.05 ) 0.05 0.002 0.5 1.5 Silver iodobromide emulsion (EM-1) Sensitizing dye■ Sensitizing dye■ Sensitizing dye V Cyan coupler (C-2) Cyan coupler (C-3) Colored cyan coupler (cc-I DIR compound (D-2) High boiling point solvent (oil-1) Gelatin 5th layer: Intermediate layer (+, L, -2) Gelatin 6th layer: Low-sensitivity green-sensitive emulsion layer (GL) Silver iodobromide emulsion (emulsion A below) Sensitizing dye ■ Sensitizing dye ■ Magenta coupler (M-2) Colored magenta coupler (CM- DIR compound (D-3) DSR compound (D-4) 2.0 2, OX 10-' 2, OX 10-' 0, IX , lO-' 0.015 0.25 ) 0.015 0.05 0.3 1.5 0.5 1.0 5 X 10-' I X 10-' 0.5 1) 0.01 0.02 0.02 High boiling point solvent (Oil-2) Gelatin 7th layer: Intermediate layer (1, L, -3) Gelatin 8th layer: High sensitivity green-sensitive emulsion layer (GH) Silver iodobromide emulsion magenta coupler (M- 3) Magenta coupler (M-4) Colored magenta coupler (CM-2) DIR compound (
D-3) High boiling point solvent (Oil-3) Gelatin 9th layer: Yellow filter layer (yc) Yellow colloidal silver stain inhibitor (SC-1) High boiling point solvent (Oil-3) Gelatin 1 theta layer: Low sensitivity blue Sensitive emulsion layer (BL) silver iodobromide emulsion (
Emulsion A below) Silver iodobromide emulsion (Emulsion B below) 0.4 1.0 0.8 ■, 8 0.05 0.15 0.05 0.0I O45 1,0 0,25 0,25 Sensitization Dye ■ Yellow coupler (Y-1) Yellow coupler (Y-2) DIR compound (D-2) High boiling point solvent (Oil-3) Gelatin 11th layer: High sensitivity blue-sensitive emulsion layer (BH) Iodobromide Silver emulsion (
Emulsion C below) Silver iodobromide emulsion (Emulsion A below) Sensitizing dye ■ Sensitizing dye ■ Yellow coupler (Y-1) Yellow coupler (Y-2) High boiling point solvent (Oil-3) Gelatin 12th layer: No. 1 protective layer (PRO-1) Fine grain silver iodobromide emulsion average grain size 0.08 μm Agl 2mol1% ultraviolet absorber (LIV-1) Ultraviolet absorber (UV-2) 7 X 10-' 0.5 0.1 0.01 O13 1,O 0,4 0,3 1X 10-' 3 X to-' 0.3 0.05 0.1 1.1 0.4 0.1 0.05 -1) 0.1
High boiling point solvent (Oil-4) 0.1
Formalin scavenger (H3-1) 0.5 Formalin scavenger (H3-2) 0.2 Gelatin ゛ 1.0 13th layer:
Second protective layer (PRO-2) Surfactant (Su-1) 0.00
5 Alkali-soluble matting agent (average particle size 3 μm) 0.1 Gelatin 0.6 Emulsion A...
・Average grain size 0.38 μm 1 Average silver iodobromide content 3, Qm
o1%, monodisperse surface paper silver iodide-containing emulsion Emulsion B...average grain size 0.27 μm1 average silver iodide content 2.0mol1%, monodisperse emulsion with uniform composition Emulsion C... An emulsion with an average grain size of 0.80 μm, an average silver iodide content of 9.0 mo1%, and a monodisperse surface containing low-order silver. In addition to the above composition, each layer contains a coating aid Su-2,
Dispersing aid 5u-3', hardeners H-1 and H-2, stabilizer 5tab i, and antifoggant AF-1 were added.

The photographic sensitivity of the prepared multilayer photosensitive material was compared when it was stored at 23° C. and 55% relative humidity for 7 days and when it was stored at 40° C. and 80% relative humidity for 7 days. The photographic sensitivity was evaluated in accordance with the method shown in Example 1. The results are shown in Table 3 (No, 6 samples 23'0, 55% R, H,
(expressed as a relative value with the sensitivity at storage as 100).

Further, a sample stored at 50° C. and 80% relative humidity for 7 days was exposed and developed according to the method shown in Example 1, and then the cyan color density was measured at an exposure amount that gave a fog of +0.6. The results are shown in Table-3.

Table 3: The light-sensitive materials containing the emulsions of the present invention show less decrease in sensitivity under high temperature and high humidity conditions, and less color turbidity, which is thought to be caused by desorption of adsorbed dyes and diffusion into other color-sensitive layers.

Sensitizing dye I Sensitizing dye■ Sensitizing dye■ Sensitizing dye■ Sensitizing dye■ Sensitizing dye■ Sensitizing dye■ Sensitizing dye■ Sensitizing dye■ C u 0M- Q 0M-2 Kiichi 5u-2 SC - iQ 2 iQ -5- iQ i12 tab- V S ■ S-2 [(CH2-CHSO*CH*)sccHzsOg (
CL)sl 2N(CH*)*SOJu-Na0sS CC00CTo(CFzCFz)JC-
COOCHz (CFsCF2)zH one leap F-1 [Effects of the invention] As described above, according to the present invention, the desorption of the sensitizing dye from the silver halide grains or the desorption thereof during the preparation of the emulsion and the storage of the light-sensitive material is prevented. Changes in adsorption state can be reduced,
It is possible to provide silver halide emulsions and photographic materials with improved manufacturing stability and storage stability and with high sensitivity.

[Brief explanation of drawings]

FIG. 1 is an absorbance spectrum showing the progress of dye desorption during emulsion stagnation.

Claims (3)

[Claims] (1) In the step of adding a silver halide solvent to an emulsion mother liquor in which emulsion grain formation of a silver halide photographic emulsion has been completed, and then distributing and adding a predetermined amount of a spectral sensitizing dye to spectral sensitize the emulsion mother liquor. A method for preparing a silver halide photographic emulsion, wherein the distributed addition time is longer than the average mixing time of the emulsion mixing and stirring to perform spectral sensitization. (2) In the step of chemically sensitizing the emulsion mother liquor in which emulsion grain formation of the silver halide photographic emulsion has been completed, a spectral sensitizing dye is added after adding a silver halide solvent, and A method for preparing a silver halide photographic emulsion, characterized in that the predetermined amount of the spectral sensitizing dye is added over a period of time longer than the average mixing time of the emulsion mixing and stirring. (3) In a photographic light-sensitive material having at least one silver halide photographic emulsion layer on a support, the silver halide photographic emulsion according to claim 1 or 2 is contained in at least one of the silver halide emulsion layers. A silver halide photographic material comprising a silver halide photographic emulsion prepared by the method described above.