JPH0354548A - Silver halide photosensitive material containing sepaloid silver halide crystal particles - Google Patents

Abstract

PURPOSE:To improve sensitivity to blue light by incorporating silver halide crystal particles with calyxes sensitized with a specified sensitizing dye into silver halide crystal particles having a specified crystal phase. CONSTITUTION:Crystal particles with calycine crystals (AB), (BC), (CA) project ing at right angles to the edge faces (a-b), (b-c), (c-a) of the regular octahedron of each normal crystal are sensitized with at least one kind of spectral sensitiz ing dye represented by formula I (where each of Y1 and Y2 is S, Se, Te or O, each of W1-W8 is H, alkyl, alkoxy, aryl, etc., each of R1 and R2 is alkyl, X is an acid anion and n is 0 or 1). A concentric effect on sensitization, expo sure or development is produced and high sensitivity to blue light is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to silver halide crystal grains having a unique shape, and further relates to a silver halide photosensitive material in which the grains exhibit an effect on photographic performance.

[Background of the invention]

In recent years, demands on silver halide emulsions for photography have become increasingly strict, with increasingly high standards required for photographic performance such as high sensitivity, excellent graininess, high sharpness, low fog density, and sufficiently high optical density. being done.

In order to meet these demands, silver iodobromide emulsions containing 10 mol % or less of silver iodide are well known as high-sensitivity emulsions. Conventionally, methods for preparing these emulsions include pH conditions such as ammonia method, neutral method, and acidic method.
) Single jet method, double jet method, etc. are known as methods for controlling Ag conditions and mixing methods. Based on these known technologies, technical means have been elaborately studied and put into practical use for the purpose of achieving high sensitivity, improved graininess, high sharpness, and low fog. In particular, research has been carried out on silver bromide and silver iodobromide emulsions in which not only the crystal phase and grain size distribution but also the concentration distribution of silver iodide within each silver iodide grain is controlled.

The most traditional way to achieve the above-mentioned photographic performance such as high sensitivity, excellent graininess, high sharpness, low fog density and sufficiently high covering power is to improve the quantum efficiency of silver halide. That's true. For this purpose, knowledge of solid state physics is actively incorporated. According to a study that theoretically calculated the thread efficiency, narrowing the particle size distribution to create a monodisperse emulsion is effective in improving the quantum efficiency. In addition, it is inferred that monodisperse emulsions are advantageous in order to efficiently achieve high sensitivity while maintaining low fog in a process called chemical sensitization in which silver halide emulsions are sensitized. For engineering monodisperse emulsion preparation, Japanese Patent Application Laid-Open No. 54-4852
As described in No. 1, it is necessary to control the theoretically determined supply rate of silver ions and halide ions to the reaction system under strict control of pAg and pH, and to provide sufficient stirring conditions. Ru. The silver halide emulsions produced under these conditions have cubic, octahedral, or tetradecahedral shapes with various proportions of (100) and (111) planes, so-called It consists of regular cubic grains. It is known that such normal crystal particles can increase sensitivity.

Furthermore, as halogenated grains capable of obtaining high sensitivity, silver iodobromide grains having excellent photographic properties and having (110) planes are disclosed in Japanese Patent Application Laid-open Nos. 61-35440 and 60-222842, respectively. In addition, in Japanese Patent Publication No. 55-42737, a rhombus with (110) face is described as having less fog.
Photographic emulsions containing dihedral silver chlorobromide grains are disclosed.

On the other hand, JP-A No. 61-83531 discloses silver bromide and silver iodobromide grains having crystal planes having a ridge line in the center of the (110) plane, and it has been shown that this allows for even higher sensitivity. It has been done. This crystal plane is considered to be a very high-order crystal plane, and its characteristics are described in Japanese Patent Application Laid-Open No. 61-83
It is stated in No. 531. The crystal plane is expressed as (nnl), and examples such as the (331) plane are shown. Other aspects are described in JP-A Nos. 62-124551, 62-124550, and 62-123447. On the other hand, silver iodobromide emulsions comprising polydisperse twin crystal grains have been known as silver iodobromide emulsions suitable for high-speed photographic films.

Moreover, silver iodobromide emulsions containing oblate twin grains are disclosed in Japanese Patent Application Laid-open No. 58-113927 and others.

Although these twin-related techniques contribute to high sensitivity, they tend to be irregular in shape and size, making it difficult to precisely control photographic characteristics, and causing problems in reproducibility. On the other hand, in the field of chemical sensitization treatment, chemical sensitization reactions for normal crystals have a large crystal phase preservation property, and for example, in normal methods, there are many sulfur sensitizing nuclei on the (111) plane compared to the (100) plane. As a result, the latent image form becomes dispersive and the efficiency is poor, and therefore, it is known that the sensitization efficiency is poor, and it is difficult to put silver halide grains having the above-mentioned (111) plane into practical use. has been considered disadvantageous or difficult.

For example, Japanese Patent Application Laid-open No. 50-63914 and German patent application (
OLS) No. 2,419,798 discloses that after sulfur-sensitizing a monodisperse silver halide grain emulsion of cubic grains with a silver bromide content molar ratio of 80% or more, a hydroxytetrazaindene compound is added. It is stated that the sensitivity increases, and this publication states that for crystal shapes other than cubic, for example, octahedral grains substantially surrounded by (111) planes, the sensitivity may actually decrease or even increase. It is also noted that the degree of damage is slight. As mentioned above, research from the perspective of crystal morphology is progressing at an impressive rate toward improving the photographic properties of silver halide photosensitive materials, but with the exception of minute concave portions of twins or concavities of tactile images, all of them are There is no research on crystals that are outwardly convex and have clearly large concave portions on the crystal plane.

However, the lines or points of intersection of the surfaces forming the concave portions are thought to exhibit specificity in the concentration of effects in chemical sensitization, exposure, and development, and development from crystals having concave surfaces is expected.

Further, crystal particles having such a concave surface are considered to have unique properties regarding adsorption of a sensitizing dye during spectral sensitization and phenomena during electron transfer.

Regarding silver halide photographic materials in recent years, many techniques have been developed to spectral sensitize silver halide emulsions so that they can be appropriately sensitized to blue, green, and red light, and this method is known as spectral sensitization. It is being done. The objectives of such spectral sensitization are that the spectral sensitization wavelength range is appropriate, that it is not reactive with various additives, that it does not deteriorate photographic properties, and that it has excellent storage stability. In addition, it must satisfy various conditions such as not causing color staining after development, and first of all, it must be able to achieve high spectral sensitivity.

Among the above-mentioned spectral sensitization methods, techniques for spectral sensitization in the blue light region include, for example, U.S. Pat. No. 3,480,
No. 434, same No. 3. 752, 670, West German Patent Application (OLS) No. 2.303.204, Special Publication No. 4
The use of sensitizing dyes described in No. 6-30023 and the like is known.

It is also known that when a pure silver bromide emulsion contains silver iodide, the long wavelength end of the inherent sensitivity range of silver halide shifts to the long wavelength side, resulting in spectral sensitization.

However, in conventional silver halide emulsions containing normal crystals and twin crystals, as the amount of sensitizing dye added increases, the inherent sensitivity of the emulsion decreases. A solution was desired.

[Problem that the invention seeks to solve]

Silver halide crystal grains that most effectively concentrate the effects of chemical sensitization, spectral sensitization, exposure or development mentioned above include:
One example is a crystal in which the concentration site is the intersection line or point of intersection of the crystal planes that form the concave surface, but this requires precise and novel control of the specific crystal structure. It is preferable that the crystal be a normal crystal without lattice defects or other singular points that would be a substantial hindrance.

However, in systems in which normal crystals with a predetermined crystal phase, especially monodisperse silver halide grains, are freely suspended, the crystal grains grow surrounded by almost isotropic planes, and there are usually no peculiarities such as crystal habit. Otherwise, there are few opportunities to exhibit anisotropy.

On the other hand, under conventional conditions that exhibit anisotropy such as twin crystals, it is difficult to precisely control grains, control the chemical jI sensitivity associated therewith, and ultimately control photographic properties.

Furthermore, conventional silver halide emulsions containing normal crystals and twin crystals suffer from desensitization due to adsorption of sensitizing dyes, and therefore, silver halide emulsions with less desensitization and high spectral sensitivity have been desired.

[Purpose of the invention]

An object of the present invention is to provide silver halide crystal grains that exhibit concentration of effects on sensitization, exposure, or development and have high blue light sensitivity when spectral sensitization is performed in the blue light region, The object of the present invention is to provide a novel silver halide photosensitive material having an emulsion layer containing the sensitized silver halide crystal grains.

[Precepts of invention]

The above objects of the present invention are achieved by a photographic light-sensitive material containing the following silver halide crystal grains. That is,
Silver halide grains in photographic emulsions, which are parallel to each other along three flat ridges formed by four edges on the same plane of a regular octahedron assumed in its normal crystal, and at right angles to each other. It is a silver halide crystal grain with a calyx piece attached with combined and overhanging crystal pieces (hereinafter, such crystal grain is also referred to as "crystal grain with a calyx piece of the present invention" etc.), and also has the general formula (1) described in detail later. This can be achieved by a silver halide light-sensitive material containing silver halide crystal grains with sepals sensitized with at least one sensitizing dye represented by:

Next, the present invention will be explained in detail. In general, silver ions arranged on the crystal plane of the silver halide crystal grains contained in the silver halide emulsion,
Depending on the dense density, lattice energy, surface energy, or predetermined length conditions of halide ions, crystal planes having a specific Miller index are dominantly expressed, giving the crystal a specific crystal phase. Furthermore, when there is a difference in the length conditions surrounding each crystal grain on a grain size scale, the sizes of the surfaces differ even though they have the same Miller index, causing a crystal habit in each grain.

On the other hand, the plane that becomes the final crystal plane that gives the crystal its crystal phase is the plane with the minimum longitudinal velocity in the normal direction of the cough plane (^Joh
nsen+ 1910)'', therefore, by selecting the Kaicho conditions, even silver halide crystals belonging to the cubic system can be given a crystal form having a predetermined crystal phase.

For example, in order to give cubic silver halide a hexahedral (cubic) crystal form as the crystal phase, the growth velocity, that is, the deposition of silver ions and halide ions on the cubic plane, is slower than on the other Miller index crystal planes. It is only necessary to provide growth conditions.

Furthermore, when changing the crystal phase from an octahedral silver halide crystal grain surrounded by (111) planes to a hexahedral (cubic) crystal phase as a host grain, a Kaicho condition that suppresses the Kaicho length of the cubic (100) plane is given. As silver halide is further precipitated, a cuboctahedron, that is, a tetradecahedron in which the six vertices of the octahedron have been shaved off, appears in the middle, and the (111) plane gradually degenerates until only the cubic face remains. The other crystal grains become cubic crystal grains as silver halide is added.

Finally, cubic crystal particles can be used as host particles to lead to octahedral crystal particles.

Similarly, for example, trioctahedral crystal grains can also be derived from cubic crystal grains as host grains. In other words, if we choose growth conditions in which the normal growth of trioctahedral crystal planes is slower than planes of other Miller indices and continue precipitation of halogenated crystals, trioctahedral crystal planes will first be recognized, and then Eventually, the host grains are occupied by trioctahedral crystal faces.

Desired crystal grains can also be obtained with other crystal grains having tetrahexahedral, rhomboid icosahedral, and hexoctahedral crystal faces by selecting growth conditions that suppress the growth of the faces that give the respective crystal phases.

The growth conditions for the silver halide grains having various crystal phases are as follows:
It is influenced by a wide variety of factors such as silver halide composition, density of ions arranged on the crystal plane, temperature, lattice or surface energy, adsorbent, halide iIJ agent, etc. A growth modifier is added as a factor that slows down the deposition of .

Many compounds are already known as growth regulators, and for photographic halogenated resins, there are photographic dyes such as soanine dyes that have adsorption properties on their surfaces, stabilizers such as azaindene and imidazole, and fog suppressants. Some of these are known to be useful. (The above-mentioned disclosed patent publication, Japanese Patent Application No. 62-15
9280 etc.).

However, at present, there is a lack of theory that relates the various factors that affect crystal elongation as described above to the crystal form formed, and there is particularly a lack of theory in the unexplored technical field of producing concave surfaces on dry crystal grains, as in the present invention. There is no proof, and we have no choice but to search for ways to realize the intended crystal form through trial and error.

In the present invention, conditions for preparing crystal particles, such as pAg,
By trial and error regarding the temperature or silver halide addition rate and fluctuation of conditions, for example, the formation and/or length of silver halide crystal grains can be adjusted to pAg 1 to 11.5 and pH 5.8 to 11.
．． 5, and at the time of growth when the crystal shape is octahedral or tetradecahedral, 1 to 300 g of cyanine dye/gX
By adding mol at once and continuing ﾾgX growth, the ridges are parallel to each other along the three planes (referred to as ridge planes) formed by the ridge lines of the octahedron, and the three ridge planes are at right angles to each other. Silver halide crystal grains are obtained in which each quadrant has concave portions with the preceding crystal plane as the bottom surface, with crystal pieces extending out along the interlocking planes.

The method of controlling the core/shell type particles is used as the particle lengthening process, and the crystal part with the calyx is considered to be a deformed shell part.

In the present invention, the specificity of the particles can be further amplified by appropriately doping a metal complex salt during the aging and/or aging of the crystal particles.

Furthermore, when the normal particles are used in a photosensitive material, it is preferable to make them monodisperse using a known method. A schematic diagram of the calyx-clipped crystal grain having a concave surface of the present invention is shown in FIG. 1, and electron micrographs are shown in FIGS. 2 to 4.

In Figure 1, an octahedral crystal is taken as an example of a host normal crystal, and (a-b), (b-c) and (ca)
is the ridge plane formed by axes a, b, and C. The figure shows only one quadrant of the three ridges. (AB), (B
C) and (CA) are sepal crystals extending parallel to the ridge surface and interlocking with each other at right angles. Figure 2 is almost the first
This is an electron micrograph of a crystal with calyx fragments seen from the angle shown in the schematic diagram. FIG. 3 shows the crystal viewed from the axes a, b or c direction. Figure 4 shows a group of crystals with calyxes in Kaichozuji.

This means that a certain length-inhibiting factor does not act in the direction of sepal length, but the reason why disc-like length progresses in this direction as a sequela in a suspended system with a homogeneous environment is probably due to the length of the twins. It seems to be.

The silver halide emulsion used in the light-sensitive material of the present invention includes those used in ordinary silver halide emulsions such as silver bromide, silver iodobromide, silver chlorobromide, and silver chloride. However, silver bromide and silver iodobromide are particularly preferred.

The silver halide grains used in the halogenated emulsion may be obtained by any of the acid method, neutral method, and ammonia method. The particles may be lengthened continuously or may be lengthened while creating seed particles in stages. The method of creating the seed particles and the method of elongating them may be the same or different.

In the silver halide emulsion, halide ions and silver ions may be mixed simultaneously, or one may be mixed in a liquid in which the other is present. In addition, while taking into account the critical lengthening speed of silver halide crystals, halide ions and silver ions were
It is also possible to control the pH and pAg in the kombu pot and add them sequentially and at the same time to make them grow. By this method, silver halide grains with a regular crystal shape and a nearly uniform grain size can be obtained. Known silver halide solvents such as ammonia, thioether, thiourea, etc. can be present during the growth of silver halide grains.

Silver halide grains are formed by at least one selected from cadmium salts, zinc salts, lead salts, thallium salts, iridium salts, rhodium salts, iron salts, and complex salts thereof. Metal ions can be added to the inside of the particles and/or on the surface of the particles, and by placing them in an appropriate reducing atmosphere, reduction can be increased inside the particles and/or on the surface of the particles. Can give a sensitive core.

In the silver halide emulsion used in the present invention, unnecessary soluble salts may be removed after the growth of silver halide grains is completed, or they may be left contained. When removing the salts, please refer to Research Discology w (Re
search Disclosure (hereinafter abbreviated as RD)
It can be carried out based on the method described in Section 17643 u.

The calyx-clipped crystal particles of the present invention are sensitized with at least one kind of spectral sensitizing dye represented by the following general formula (1). That is,
The light-sensitive material of the present invention contains at least one kind of spectral sensitizing dye represented by the same formula. In that case, the calyx-clipped crystal particles according to the present invention are sensitized with the sensitizing dye.

General formula (1) However, Y, and Yt are S, Se, Te, or ○.

w. ,w, ,w. ,w. ,w,,w&,W,,
W8 is H, an alkyl group, an alkoxy group, an aryl group,
A halogen atom, an amino group, an acylamido group, an acyloxy group, an alkoxycarbonylamino group, an alkoxy carbonyl group, or a hydroxy group, and W-, Wz, WX
and W3, W4 and Ws, W, and W,, W1 and W? , W4 and W may be bonded to form an aromatic carbon ring or aromatic heterocycle. R1. RZ is an alkyl group.

X is an acid anion.

n is O or l, and when forming an inner salt,
n=o.

In the above general formula (1), R. and R2 is preferably an alkyl group having a carboxyl group or an alkyl group having a sulfo group, and R+
Alternatively, when R2 represents the above group, the remaining one is preferably an unsubstituted alkyl group, and this alkyl group is preferably a lower alkyl group, such as methyl, ethyl, probyl, butyl, and the like. Examples of anions represented by XS include chloride, bromide, iodide, thiocyanate, sulfamate, methyl sulfate,
Examples include ethyl sulfate, perchlorate, and p-toluenesulfonate. In general formula (1), Y1 and Y2 may be the same or different and represent a sulfur atom, an oxygen atom, a tellurium atom, or a selenium atom, and W1 to W8 are
Hydrogen atoms, halogen atoms (e.g. chlorine, bromine,
iodine, fluorine), hydroxyl group, alkoxy group (e.g. methoxy, ethoxy, propoxy, putoxy, etc.), amino group (e.g. amino, methylamino, dimethylamino,
diethylamino), acylamido groups (e.g. acetaξ
etc.), acyloxy groups (e.g. acetoxy, propionoxy, etc.), alkoxy carbonyl groups (e.g. ethoxycarbonyl, propoxycarbonyl, etc.), alkoxy luponylamino groups (e.g. ethoxy luponylamino, broboxycarbonylamino, butoxy) carbonylamino, etc.), alkyl groups (e.g. methyl, ethyl, probyl, etc.), and aryl groups (e.g. phenyl, tolyl, etc.). W1 and W2, Wt and Wx, W4 and Ws, Ws
and wh, W, and W'l, W4 and W. may be linked together to form, for example, a benzene ring. This benzene ring may have a substituent. Typical specific examples of the sensitizing dye represented by general formula (1) that can be used in the present invention are described below, but the dye that can be used in the present invention is limited only to these compounds. isn't it.

The sensitizing dye represented by the general formula (1) as exemplified above is a known compound, for example, U.S. Pat.
49. No. 105, No. 2,238,231, British Patent No. 742,112 or "The Cyanine Soybean and Related Compound" by F.M. Herma (Interscience Publications, NY) (1964), p. 55, et seq., those skilled in the art can easily synthesize those not described by similar methods.

The sensitizing dye represented by the above general formula (1) may be used alone or in combination of two or more types. (For example, see JP-A-59-116645). Furthermore, the sensitizing dye according to the present invention can also be used with a substantially colorless compound known as a sensitizing dye or supersensitizer other than the sensitizing dye represented by the general formula (1'j). For example, U.S. Patent No. 2,933.390;
No. 511,664, No. 3615.613, No. 3,
Compounds having a pyriξdinylamino group or triazinylamino group described in No. 615.632, No. 3,615,641, etc., and aromatic organic acid monoformaldehyde described in British Patent No. 1.137,580. It may also contain condensates or cadmium salts. Furthermore, as a method for adding the above-mentioned sensitizing dye to a photographic emulsion, various methods that have been proposed in the past can be applied. For example, as described in U.S. Pat. No. 3,469,987, a sensitizing dye is dissolved in a volatile organic solvent, the solution is dispersed in a hydrophilic colloid, and this dispersion is added to an emulsion. You can. Furthermore, the sensitizing dyes according to the present invention may be individually dissolved in the same or different solvents,
These solutions can be mixed or added separately before being added to the emulsion. When a sensitizing dye is added to a silver halide emulsion, a water-miscible organic solvent such as methyl alcohol, ethyl alcohol, acetone, etc. is often used as a solvent for the dye.

When the sensitizing dye is added to the silver halide emulsion, the preferred addition rate is from 2.times.10'' moles to IXIO-' moles per mole of silver halide.

The light-sensitive material of the present invention uses silver halide grains that have regular crystal shapes such as cubes, octahedrons, and dodecahedrons, as well as spherical and plate-like silver halide grains, in addition to the calyx-shaped crystal grains produced by the present invention. It may also be used in combination with those having irregular crystal forms.

The particle size of halogenated particles is 0.05 to 3μ.
m, preferably 0.1-3. A material with a diameter of 0 μm can be used.

The silver halide grains used in combination may have any grain size distribution. An emulsion with a wide grain size distribution (referred to as a polydisperse emulsion) may be used, or a monodisperse emulsion with a narrow grain size distribution may be used. Monodispersity as used herein means that the standard deviation of the particle size distribution divided by the average particle size is 0.20 or less.

Monodisperse emulsions may be used alone or in combination. Furthermore, a polydisperse emulsion and a monodisperse emulsion may be mixed and used. The silver halide emulsion may be a mixture of two or more different types of silver halide emulsions.

In the present invention, various commonly used chemical sensitization treatments can be performed. Chalcogen sensitizers used in chemical sensitization include sulfur sensitizers, selenium sensitizers, and tellurium sensitizers, and sulfur sensitizers and selenium sensitizers are preferred for use in photography. As the sulfur sensitizer, known ones can be used. For example, thiosulfate, allylthiocarba ξ
de, thiourea, allyl isothiocyanate, cystine,
Examples include p-toluenethiosulfonate and rhodanine. In addition, U.S. Patent No. L574,944, U.S. Patent No. 2,
No. 410,689, No. 2,278,947, No. 2,
728. No. 668, No. 3,501,313, No. 3,
No. 656,955, OLS No. 1,422
．． No. 869, JP-A-56-24937, JP-A No. 55-45
Sulfur sensitizers described in No. 016 and the like can also be used. The amount of sulfur sensitizer added may be sufficient to effectively increase the sensitivity of the emulsion. This appropriate amount depends on pH, temperature,
The amount varies over a considerable range depending on various conditions such as the size of silver halide grains, but as a rough guide, it is preferably about 10<-7 >mol to about 10<-1 >mol per 1 mole of halide.

Examples of selenium sensitizers include aliphatic inselenocyanates such as allyl isoselenocyanate, selenoureas, selenoketones, selenoamides, selenocarboxylic acids and esters, selenophosphate a, diethylselenide, diethyl diselenide. Selenides such as
No. 4,944, No. 1,602,592, No. 1,623
, No. 499. As with the sulfur sensitizer, the amount added varies over a wide range, but as a guide, approximately 10
-'mol to about 10-'mol is preferable.

In the present invention, various gold compounds are used as the gold sensitizer, whether the gold has a valence of +1 or +3. Typical examples include chloroauric acids, kawaum chloroaurate, and auric trivalent. Examples include chloride, potassium auric thiocyanate, potassium iodoaurate, tetracyano auric acid, ammonium aurothiocyanate, biridyl trichloride gold, and the like.

The amount of gold sensitizer added varies depending on various conditions, but as a guide, it is about 10-7 to 10 mol per mol of silver halide.
A range of up to -' moles is preferred.

The gold sensitizer may be added at the same time as the sulfur or selenium sensitizer, or during or after the sulfur or selenium sensitization step.

The pAg of the emulsion subjected to sulfur sensitization, selenium sensitization, and gold sensitization in the present invention is 5.0 to 10.0, and the pH is 5.
．． The range of 0 to 9.0 is preferable. The chemical sensitization method of the present invention can also be combined with a sensitization method using other noble metals, such as metal salts such as platinum, palladium, iridium, and rhodium, or complex salts thereof. Further, as a compound that desorbs gold ions from gold-gelatinate with N and promotes gold ion adsorption to silver halide grains, Rh. ．． Complexes such as Pd, Ir, and PC are effective.

As a specific compound, (NHn)z [P tC i
4], (Ntl4) z [P tc j2 a),
L [IrBr6l, (NH4) :l fRhc
l bl 12IhO, etc., and particularly preferred is ammonium tetrachloride (If) acid (NH4) zPtcjl: a. The amount added is preferably 10 to 100 times the stoichiometric ratio (molar ratio) to the gold sensitizer. The timing of addition may be at the start of, during, or after the chemical sensitization process, but preferably during the chemical sensitization process, and particularly preferably at the same time as or before or after the addition of the gold sensitizer. It is. In the present invention, reduction sensitization can also be used in combination. There are no particular restrictions on the reducing agent, but known examples include stannous chloride, thiourea dioxide, and hydrazine.
Examples include i-form, polyamine, and the like. Reduction sensitization is carried out during the growth of silver halide grains, but it is preferably carried out after completion of chalcogen sensitization, gold sensitization and noble metal sensitization.

Furthermore, in the chemical sensitization treatment, a compound having a nitrogen-containing heterocycle, particularly preferably an azaindene ring, may be present together.

The amount of the nitrogen-containing heterocyclic compound added depends on the size of the emulsion grains, &[
Although it varies over a wide range depending on the molecular weight and chemical sensitization conditions, it is preferably added in an amount that forms a monomolecular layer to 10 molecular layers on the surface of the silver halide grains. The amount added can also be adjusted by controlling the adsorption equilibrium state by changing the pH and/or temperature during sensitization. Further, the above-mentioned compounds may be added to the emulsion in such a manner that the total amount of two or more compounds falls within the above range. The compound can be added to the emulsion by dissolving it in a suitable solvent (for example, water or aqueous alkaline solution) that does not have a harmful effect on the photographic emulsion, and then adding it as a solution. The timing of addition is preferably before or at the same time as adding a sulfur sensitizer or a selenium sensitizer for chemical sensitization. The gold sensitizer may be added during or at the end of sulfur or selenium sensitization.

Further, the silver halide grains can be optically sensitized to a desired wavelength range using a sensitizing dye.

Antifoggants and stabilizers 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 and can contain a plasticizer and a dispersion (latex) of a water-insoluble or sparingly soluble synthetic polymer.

A coupler is used in the emulsion layer of color photographic materials. Furthermore, by coupling with colored couplers that have a color correction effect, competitive couplers, and oxidized forms of developing agents, development accelerators, bleaching accelerators, developing agents, silver halide solvents, toning agents, and hardening agents can be produced. , fogging agent, antifogging agent,
Compounds that release photographically useful fragments such as chemical sensitizers, spectral sensitizers, and desensitizers can be used. The photosensitive material may 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 of the light-sensitive material or bleached 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 the support, paper laminated with polyethylene or the like, polyethylene terephthalate film, baryta paper, cellulose triacetate, etc. can be used.

When a dye image is obtained using the light-sensitive material of the present invention, commonly known color photographic processing can be performed after exposure.

〔Example〕

EXAMPLES Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited thereto.

Prior to the examples, comparative emulsions will first be shown.

Comparative Example 1 Comparative emulsion EM-1 was prepared using seven types of solutions shown below.

(Solution A) Ossein gelatin 68 g CH, 1 [0{CIIzCIIzOh{CIICIIzOhdC
10% ethanol solution of IlzCIIzOh”H average molecular weight 1700 ・Prononone CF 3 oils and fats 20 d2
8% ammonia water 104 d56%
Acetic acid aqueous solution 62 type emulsion (0.2
7 μm, tetradecahedral silver iodobromide (AJI content: 2.0 mol%) 6771 d equivalent to 0.139 mol of silver halide Distilled water (solution B) Ossein gelatin KBr Make up to 3383 cc with distilled water.

(}Liquid C) A g N 01 28% ammonia water 67.6g 845.4 g 1177 960 Make 3299d with distilled water.

(Solution D) 50% KBr aqueous solution 1'Ag adjustment required (Solution E) 50% acetic acid aqueous solution pH adjustment required amount 40°C
In, JP-A-57-92523, JP-A No. 57-925
Solutions B and C were added to solution A by simultaneous mixing method for 73.7 minutes using a mixing stirrer shown in No. 24.

During simultaneous mixing, the addition rates of OPAg, pi{, and solutions B and C were controlled as shown in Table 1. f) Ag and pH were controlled by changing the flow rates of solution D and solution E using a variable flow rate roller tube pump. Two minutes after the addition of Solution C was completed, the pH was adjusted to 6.0 by adding a solution.

Next, it was washed with demineralized water using a conventional method and dispersed in an aqueous solution containing ossein gelatin.

According to electron microscopy, this emulsion has an average grain size of 1.0 μm.
The emulsion was found to be a highly octahedral monodisperse emulsion with a coefficient of variation of grain size distribution of 12%.

Table 1 Example 1 Emulsion EM-2 containing calyx-clipped crystal grains of the present invention was prepared in the same manner as in Comparative Example 1, except that the following two types of photosensitive dye aqueous solutions were added 43.2 minutes after the start of addition. .

0.2% methanol aqueous solution of photosensitive dye (1) 0.2% methanol aqueous solution of 736 photosensitive material (II) 864 sensitizing dye (1) Sensitizing dye (U) Sensitizing dye adsorbed on this silver halide emulsion EM-2 The sensitive dye was removed by the following method to produce a silver halide emulsion EM-3 with sepals that had not been spectrally sensitized.

That is, extraction treatment with a solvent was performed to remove the sensitizing dye. The above-prepared silver halide emulsion EM-2 to which the sensitizing dye had been adsorbed was subjected to a sensitizing dye imaging process by adding methanol under acidic conditions.

The emulsion was then allowed to settle and the supernatant liquid was discarded. This process was repeated several times to create emulsion EM-3, which had only intrinsic sensitivity.

Example 2 Next, an example of a silver halide color light-sensitive material using the emulsion according to the present invention will be shown.

Here, a case will be described in which the present invention is applied to a sample consisting of an emulsion layer containing a coupler.

In this example, a yellow colored coupler was used. Specifically, in this example, as a yellow coloring coupler,
A coupler represented by the following formula (A) was used.

Tricresyl phosphate (TCP) was employed as a high boiling point solvent for dissolving the formula (A) coupler.

The coupler was oil-protected and dispersed according to a conventional method.

Next, the silver iodobromide emulsion (E
M-1, EM-2.2 and M-3) were optimally chemically sensitized using an unstable sulfur compound and a gold salt according to a conventional method.

Further, during chemical sensitization, the sensitizing dyes shown in Table 2 were added to increase the color sensitivity to blue.

Silver iodobromide emulsion 1.8 subjected to the above chemical sensitization and color sensitization
A high-speed blue-sensitive emulsion layer containing 0.06 g of TCP (1-licresyl phosphate) dispersion in which 1.9 g of gelatin and 0.20 g of yellow coupler was dissolved was prepared.

Each sample was wedge exposed using blue light according to a conventional method and subjected to sensitometry.

Each exposed sample was processed in the next processing step.

Processing steps: Color development 3 minutes 15 seconds bleaching 6 minutes 30 seconds water
Wash 3 minutes 15 seconds Fix
Wash with water for 6 minutes and 30 seconds
Stabilization for 3 minutes and 15 seconds Drying for 1 minute and 30 seconds The processing solutions used in each treatment step are shown below.

Color developer> 4-amino-3-methyl-N-(β-hydroxyethyl)-aniline sulfate 4.75g Anhydrous sodium sulfite 4.25g Hydroxylamine A
Sulfate 2.0g Anhydrous potassium carbonate
37.5 g sodium bromide
1.3g nitrilotriacetic acid trisodium salt (
(monohydrate) 2.5g Potassium hydroxide 1.0g Add water to make IQ.

<Bleach solution> Ethylenediaminetetraacetic acid iron ammonium salt 100. 0 g
Ethylenediaminetetraacetic acid diammonium salt 10.0 g Ammonium bromide 150.0 g Glacial acetic acid io. Add o ml water to make 1 liter, and adjust the pH to 6.0 using ammonia water. <Fixer> Ammonium thiosulfate 175.0 g
Anhydrous ammonium sulfite 8.6 g Sodium metasulfite 2.3 g Add water to make 1 liter, and adjust the pH to 6.0 using acetic acid. <Stabilizing liquid> Formalin (37% liquid) 1.5
d Konidax (manufactured by Konica ■) 7.5
d Add water to make 1 liter.

The developed sample was subjected to sensitometry using blue light.

Fog: the lowest optical density of the so-called characteristic sensitivity curve obtained by sensitometry (the larger the value, the higher the fog, which is undesirable).

Degree: Reciprocal of the exposure amount (anti-value) that gives an optical density of fog + 0.1 on the characteristic curve (In the table of results of the example, the sensitivity of sample Nα1 during normal exposure (1/50 second refraction) 10
Relative values are set as 0: the larger the value, the faster the sensitivity, which is preferable).

Actual concentration: The value obtained by subtracting the maximum concentration from the maximum concentration on the characteristic curve. (In Table 2, the actual density of sample Nα1 is set as 100 and relative values are calculated. The larger the value, the faster the development speed is, which is preferable.) The results are shown in Table 2.

Margin Table 2 below It turned out to be.

Example 3 Precautions for multilayer color photosensitive material (referred to as multilayer sample): Silver iodobromide subjected to the same chemical sensitization and color sensitization as used in preparing the single color sensitive coating sample described above. Using the emulsion, a color photosensitive material consisting of nine layers having three types of photosensitive layers, a blue photosensitive layer, a green photosensitive layer, and a red photosensitive layer was prepared as follows.Chemical sensitization and color sensitization were performed. EM-1, EM-3
The emulsion was changed only in the blue-sensitive high-speed layer (eighth layer). For the other photosensitive layers, the same emulsion was used in each sample.

It consists of an undercoated cellulose triacetate film with an antihalation layer (0.40 g of black coroitic silver).
and 3.0g of gelatin. Samples were prepared by coating each of the following layers in order on a transparent support (1) having a material (1). In all of the following examples, the amounts added to the light-sensitive materials are shown per unit, and are shown in terms of silver halide emulsion and colloidal silver. Layer 1: 1.4 g of low-sensitivity red-sensitive silver iodobromide (containing 7 mol% silver iodide) emulsion color-sensitized to red sensitivity and 1.2 g
of gelatin and 0.8 g of l-hydroxy-4-(β
-methoxyethylamino(lponylmethoxy)-N-
(δ-(2.4-di-L-alphenoxy)butyl)
-2=naphthamide [hereinafter referred to as C-1]. ], 0.0
75 g of 1-hydroxy-4-(4-(1-hydroxy-δ-aceto-ξ-3,6-disulfo-2-naphthylazo)phenoxy)-N-(δ-(2,4-di-L-
amylphenoxy>butyl-2-naphthamide disodium [hereinafter referred to as colored cyan coupler (CC-1). ] and 0.015 g of 1-hydroxy-2-
[δ-(2.4-di-L-amylphenoxy)butyl]
Naphthamide, 0.07 g 4-octadecylsuccinido-2-(l-phenyl-5-tetrazolylthio)
-1-indanone [hereinafter referred to as DIR compound (D-1)]. 〕these? A slow red-sensitive emulsion layer containing 0.65 g of dissolved tricresinolephosphate (TCP) dispersion.

1.2...1.3 g of high-sensitivity red-sensitive silver iodobromide emulsion 1.
2 g gelatin and 0.21 g cyan cobbler (C
-1) and 0.02g of colored cyan cabra (C(
, -1), a high-speed red-sensitive emulsion layer containing a 0.23H TCP dispersion in which . Layer 3...0.07g 2
, 5-di-t-octylhydroquinone [hereinafter referred to as antifouling agent (HQ-1). ) dissolved in 0.04 g of dibutyl phthalate (hereinafter referred to as DBP). ] Intermediate layer containing the dispersion and 0.8 g of gelatin. /t'l4...o.color sensitized to green sensitivity. sog's low-sensitivity silver iodobromide emulsion (containing 6 mol% silver iodide) and 2.2 g
of gelatin and 0.8 g of 1-(2,4.6-trichlorophenyl)3-(3-(2,4-di-amylphenoxyacetate)benzado]-5-pyrazolone, 0 .15 g of 1-(2,4.6-trichlorophenyl)-4-(1-naphthylazo)-3-(2
-Chloro-5-octasecenylsuccinimide anilino)-5-pyrazolone, sakukai [hereinafter referred to as colored magenta cobra (CM-1). ) 0.95 g of TCP in which 0.016 g of DIR compound (D-1) was dissolved
A low-speed green-sensitive emulsion layer containing a dispersion.

Layer 5...1.8g chemically sensitized and color sensitized to green sensitivity
A high-sensitivity green-sensitive silver iodobromide emulsion of High speed green sensitive emulsion layer containing .06 g of DNP dispersion.

Layer 6...o. is g yellow colloidal silver, 0.2g
0.11g of DB containing antifouling agent (HQ-1)
Yellow filter layer containing P fraction and 1.5 g gelatin.

Layer 7: 0.2 g of low-sensitivity silver iodobromide (containing 4 mol% silver iodide) emulsion sensitized to blue sensitivity, 1.9 g of gelatin, and 1.5 g of α-vivaloyl-α- (1-benzyl-2-phenyl-3,5-dioxoiξdazolidine-
4-yl)-2'-chloro-5'-[α-dodecyloxycarbonyl)ethoxycarbonyl]acetanilide [hereinafter referred to as Y-1. ]0.6g of TC dissolved in
A low-speed blue-sensitive emulsion layer containing a P dispersion.

Layer 8...1.0 chemically sensitized and color sensitized to blue sensitivity
The high-speed blue-sensitive silver iodobromide emulsions (EM1, EM-3)
), a high-speed blue-sensitive emulsion layer containing 0.65 g of TCP dispersion in which 1.5 g of gelatin and 1.30 g of yellow coupler (Y-1) were dissolved. See Table 3 for the type and amount of sensitizing dye and type of emulsion.

Layer 9: Protective layer with 2.3 g of gelatin.

Measurement of multilayer sensitivity: The multilayer color light-sensitive material thus prepared was exposed to white wedge light according to the conventional method, processed in the above processing steps, and blue light sensitivity was obtained by sensitometry (the definition of sensitivity is based on the above-mentioned simple method). (same as for monochromatically coated samples).

The results are shown in Table-3.

Margin Table 3 M-1 As seen in Table 3, the samples of the present invention have little fog and high sensitivity. Furthermore, the actual density is high and the development activity is high. As described above, it was found that the effects of the present invention can be obtained even with a sample having a multilayer structure, as in Example 2.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a silver halide crystal according to the present invention. Furthermore, FIGS. 2, 3, and 4 are electron micrographs of silver halide crystals according to the present invention.

Claims (1)

[Scope of Claims] 1. Silver halide crystal grains of a photographic emulsion, each of which has four particles lying on the same plane of a regular octahedron assumed in its normal crystal.
It is a crystal grain that is parallel to the three planes formed by the three edges, and has crystal pieces attached to it that extend out by combining them at right angles to each other, and it is also a crystal grain that is attached to a sensitizing dye represented by the following general formula (1). A silver halide photographic light-sensitive material comprising silver halide crystal grains with sepals sensitized with at least one kind. General formula (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ However, Y_1 and Y_2 are S, Se, Te, or O. W_1, W_2, W_3, W_4, W_5, W_6
, W_7, W_8 are H, alkyl group, alkoxy group,
An aryl group, a halogen atom, an amino group, an acylamido group, an acyloxy group, an alkoxycarbonylamino group, an alkoxycarbonyl group, or a hydroxy group, W_1
and W_2, W_2 and W_3, W_4 and W_5, W_5 and W_6, W_1 and W_7, and W_4 and W_8 may be bonded to form an aromatic carbocycle or an aromatic heterocycle. R_1 and R_2 are alkyl groups. X is an acid anion. n is 0 or 1, and when forming an inner salt,
n=0.