JPH0234A - Silver halide emulsion and its production - Google Patents

Abstract

PURPOSE:To obtain the silver halide emulsion having a high sensitivity and an excellent development progress by composing a silver halide particle contg. in an emulsion of a particle which has the crystal surface of crystal faces (100) and (111) on the surface of one of the particle and a different halogen composition. CONSTITUTION:The AgX emulsion contg. a dispersion medium and the silver halide AgX particle is composed of the particle which has crystal surfaces of the crystal faces (100) and (111) on the surface of >=70% of the total projected area and the different halogen composition on the surface layer of the particle respectively. The position of the chemical sensitizing nucleus of the particle is controlled by differing the halogen composition on the crystal surface of the particle or the formability of the chemical sensitizing nucleus composed of an effective electron trap and/or the absorbing property due to the halogen composition on the substrate of an adsorbent. Thus, the silver halide emulsion which has the excellent sensitivity, gradation, reciprocity law failure and development progress, is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention provides silver halide (silver halide) useful in the field of photography.
Regarding emulsions (hereinafter referred to as AgX), in particular, a dispersion medium and one A
On the gX particle surface, at least (100) and +111
The present invention relates to an AgX emulsion consisting of AgX grains having one crystal surface.

(Prior art and its problems) Generally, in order to produce highly sensitive photosensitive AgX particles, it is necessary to control the position and number of chemically sensitizing nuclei that serve as photosensitive centers. The limiting method is: 1) Growing epitaxial particles on the corners and edges of AgX particles with or without adsorption using a halogen conversion method or by adding AgNOx and a halogenated alkali solution. , a method in which the adsorbent is adsorbed and stabilized, and then chemically sensitized to limit the latent image formation position to the epitaxial region.

Regarding this, please refer to JP-A-58-108526 and JP-A-58-108526.
-133540 and 62-32443 can be referred to.

■ A method in which additives such as aggravating dyes are added during particle formation to introduce defective areas into the particles, and chemical sensitization nuclei are preferentially formed only in these defective areas.

This method is a method for controlling the number of chemically sensitized nuclei by introducing defects into particles. Regarding these, see U.S. Patent No. 2,735,766, U.S. Patent No. 3°628.960, U.S. Patent No. 4,183,756, U.S. Pat.
P, 155 (1980) may be referred to.

■ A with two or more types of crystal planes on one AgX particle
A method of forming chemical sensitizing nuclei only on one crystal face using gX particles and taking advantage of the difference in reactivity of a sulfur sensitizer to those crystal faces.

For example, when using an emulsion with pH 6.4 and pAg 8.4 at 40°C, the reactivity of sulfur sensitization by hypo is +111
A method of forming chemical sensitizing nuclei only on the (111) plane of a tetradecahedral particle using the fact that 1 plane>[1001 plane, in this case, a tetradecahedral particle with different ratios of (111) area and 1100) area. This is a method of controlling the position and number of chemically sensitized nuclei by using Regarding this, J, Pho
t, Sci.

23.249 (1975) Journal of the Photographic Society of Japan, vol. 47,
P, 255 (1984), Figure 3 may be referred to.

■ Adsorbent 1 (sensitizing dye, antifogging agent,
There is a method of chemical sensitization by adsorbing additives such as stabilizers and then adding a chemical sensitizer.

In this method, chemically sensitized nuclei are formed only in areas where no adsorbent is adsorbed, so the number of chemically sensitized nuclei is controlled, but the position is not controlled. No. 58-113926, No. 58-113927,
No. 58-113928, U.S. Patent No. 4,439,520
No. 4,435.501, Re5earch Di
sclosure, Itam, 17643, 5e
ction m, JP-A-62-6251. Japanese Unexamined Patent Publication No. 1983-
126526, JP-A-62-56949, JP-A-62-
43644.

■ AgX particles with two or more types of crystal planes on the surface of one AgX particle are used, and an adsorbent that is selective for adsorption to those crystal planes (surface-selective adsorbent) is added to increase the density of the adsorbent. After forming an adsorbed crystal plane and a crystal plane on which the adsorbent is loosely adsorbed, a chemical sensitizer is added to chemically sensitize it, and chemically sensitized nuclei are formed on the crystal plane on which the adsorbent is loosely adsorbed. Method.

Regarding this, JP-A-58-113928 describes that ``The spectral sensitizing dye is preferentially adsorbed on the crystal surfaces forming the main surfaces of the tabular grains, so that chemical sensitization differs from one another in the tabular grains. There is a short description that ``can occur on crystal surfaces''.

This method attempts to control the number and location of chemically sensitized nuclei.

The present invention relates to improvements in methods (1) and (2) among these methods.

However, the following problems remain with method (2).

(11 In this case, the adsorbent that can be used is AgX
It is limited only to compounds whose adsorption ability is highly dependent on crystal habit, and the selection range of adsorbents to be used is greatly restricted.

(2) In order to limit the formation sites of chemically sensitized nuclei, it is preferable that the adsorption of the adsorbent be strong, but this is contrary to the fact that the adsorption capacity is crystal habit dependent.

That is, in general, strongly adsorbing additives strongly adsorb to any surface, so dependence on crystal habit is small.

Generally, there is a problem that the adsorption power of dyes and additives whose adsorption ability is highly dependent on crystal habit is weak. Therefore, chemical sensitizing nuclei are also formed on the crystal planes on which the sensitizing dye and additives have been adsorbed, and the ability to form chemical sensitizing nuclei W is insufficiently controlled.

(3) On the other hand, method (■) also has the following problems. It is known that the reaction of sulfur sensitizers is also crystal habit dependent, but the difference in reactivity is not sufficient. For example, when ripening is performed using Hypo under emulsion conditions of 50°C, pH 6.4, and pAg 8.5, in the low concentration range of Hypo,
The reaction occurs selectively on the +1111 plane compared to the (l OO) plane, but when a gold sensitizer is added together, the difference becomes smaller.

Also, although this is not known, the reverse case, for example,
When trying to form a chemically sensitized nucleus only on the +1001 plane using triethylthiourea, its (100} and {11
The situation is such that the difference in reactivity on the 11 faces is not sufficient, and if a gold sensitizer is used in combination for ripening, the face selectivity of the reaction is almost completely lost.

(Objective of the Invention) The object of the present invention is to provide a silver halide emulsion in which the position and number of chemically sensitizing nuclei are sufficiently controlled, thereby improving the degree of anger, gradation, reciprocity properties, development progress, and stability over time. The object of the present invention is to provide a silver halide emulsion capable of improving graininess, graininess, sharpness, and resolution.

4. Disclosure of the Invention The purpose of the present invention is to produce an AgX material consisting of a dispersion medium and AgX particles.
In the emulsion, 70% or more of the total projected area of AgX grains,
Preferably 80% or more, more preferably 90% or more is 1
At least +1001 and (111) crystal surfaces exist on the surfaces of two silver halide grains, the halogen compositions of the surface layers of the crystal surfaces are different from each other, and the chemical aggravation nuclei are preferentially located on one crystal surface. A characterized by being formed
This was achieved with gX emulsion.

Conventionally, for example, the +1001 face or +1 face of a tetradecahedral particle
When forming chemical sensitizing nuclei on one of the 111 crystal faces, simply
In contrast to the method that utilizes the difference in adsorption to the fl 001 plane and the fl 111 plane) + (the difference in the reactivity of the sulfur sensitizer to the fl 001 plane and the +1111 plane), the method of the present invention
By changing the halogen composition of the surface layer of the +1001 plane and the T1111 plane, the above (■) difference in the ability to form chemically sensitized nuclei, which becomes an effective electron trap for O in addition to O;
Or, it utilizes (differences in adsorption properties due to the halogen composition of the adsorbent substrate) + (differences in the ability to form chemically sensitized nuclei that become effective electron traps), and its discrim
By increasing the ination factor, the position of the chemosensitizing nucleus can be more fully controlled.

First, the structure of the AgX particles of the present invention will be explained in detail, and then the method for producing SiAgX particles will be explained in detail.

The AgX grains of the present invention are grains having crystal surfaces of at least fl O01 and fl 111 on the surface of one AgX grain, but more specifically, they include tetradecahedral grains and tabular grains having parallel twin planes. It is.

It is well known that the outer surface of a tetradecahedral grain has a +1001 face and a (111) face, but in the case of a tabular AgX grain, T, F, Hamilton and L,
E.

Brady (Journal of Applied
Physics, Volume 35, P.

414-421.1964), both the parallel main outer surfaces and the outer surfaces of the edge portions are +1111 planes.

In other words, the entire surface is [1111 planes, single tw
It can be thought of as a structure in which in particles are simply piled up.

However, the tabular grains described in Japanese Patent Application No. 62-203635 by the present inventors have (100) faces in the edge portions.The tabular grains as used in the present invention are particles having such a form.

The AgX particles of the present invention have at least a TI O01 plane and a fl 111 plane on one AgX particle, but the +
The average value of area of 1111 sides/+1001 areas is 14
In the case of facepiece particles, it is 20 to 1/20, preferably lO to 1
/10, and in the case of tabular grains it is 20 to 1.0. Preferably it is 15-2.0. In addition, this (1113 side and (
The area ratio of the 100) plane is measured using the dependence of the adsorption of the sensitizing dye on the (1111 plane and (100) plane (T, Tan
1 Journalofl+aaging 5cien
ce, 29. 165 (1985)).

However, when the area ratio is clear from the electron micrograph image, such as a tetradecahedral particle, the area ratio can be determined from the electron micrograph.

The AgX particles of the present invention are characterized in that the halogen compositions of the surface layers on the (100) and 1111) crystal surfaces are different from each other. Refers to the crystal layer of the lattice.

The halogen composition of the surface layers of the (100} and {111) crystal surfaces of the AgX particles of the present invention is characterized by being different from each other, which preferably differs in the immersion content and/or the C1 content. If they are different, it is preferable that they differ from each other by 2 to 40 mol%, preferably from 3 to 30 mol%. In this case, the chemical sensitizing nuclei are preferentially located on the crystal surface having the low iodine content surface layer. Preferably, the surface layer of the crystal surface (hereinafter referred to as A-side) where chemically sensitized nuclei are preferentially formed has a immersion content of 5 mol% or less, and 3 mol% or less. is more preferable.

The immersion content of the surface layer of the crystal surface where chemical sensitizing nuclei are not preferentially formed (hereinafter referred to as B-side) is preferably 2 mol% to the solid solubility limit, and more preferably 3 to 35 mol%.The reason is (1) - In melon, adsorbents such as cyanine dyes preferentially and strongly adsorb onto crystal surfaces having a high iodine content surface layer, so that chemical sensitizing nuclei are formed on the crystal surface having a high iodine content surface layer. This is because it is more difficult to form.

■ When chemical sensitization is performed on a crystal surface with a high iodine content layer, Ag-S nuclei and Ag-Au-3 nuclei are formed;
This is because they are difficult to become effective electron traps, and as a result, it tends to be difficult to form effective chemical aggravation nuclei.

This is E, Mo1sar (1, C, P, S, T
OKYO+ 1967) and 11. old rsch (1,
Phot, Scr,, 20. 187 (1972
Monodisperse normal crystal emulsions with the same grain size and varying immersion content in the surface layer were prepared according to the method of 2010).
These are the results of sulfur-sensitization and measurement of its reflection spectrum.

In addition, when the C1 content is different, 7 to 10
The difference is preferably 0 mol %, preferably 10 to 80 mol %. In this case, it is preferable that the chemical sensitizing nuclei are preferentially formed on the crystal surface where the high 01 content layer is present.

The reason is that adsorbents such as cyanine dyes are generally AgC
j! This is because Br particles are more strongly adsorbed onto the crystal surface having a high Br content surface layer, so that chemical aggravation nuclei are less likely to be formed on the crystal surface having the high Br content surface layer.

Generally, the adsorption strength of cyanine dye is AgC1→AgBr-
It is known that the strength increases in the order of AgBr+.

The ti o o+ of the AgX particles of the present invention and the halogen composition of the surface layer on the (111) crystal surface are different from each other, but this is because the I! of the AgX particles is different from each other. Iectron ProbeMic
It can be investigated by the roanalysar (EPMA) method or the like.

In the °AgX particles of the present invention, it is more preferable to have one or more adsorbents adsorbed on the 8 faces. In this case, the adsorbents include: (a) an adsorbent whose adsorption power varies depending on the halogen composition of the substrate; .

Mountain 1 Adsorbents having different adsorption powers for the (111) and (100) crystal planes are preferable.

Generally, the adsorption strength of cyanine dye is AgC1-AgBr-
It is known that the strength increases in the order of =AgBrl, which meets the purpose of the present invention.

Regarding the adsorption properties of these adsorbents, T, H, Ja
mes+ The Theory of the Ph
otographicProcess, Fourth
Edition, Macmillan+ New
York.

1977, Chap, 9. Chap, 1. Ch
You can refer to the description in AP, 13.

In the case of tabular grains, the A-plane is (11, from the 11-plane
The +1001 plane is preferable because in tabular grains, the area ratio of the crystal to the surface of the +1001 plane is overwhelmingly smaller, and therefore the number and position of chemically aggravated nuclei can be more controlled.

On the other hand, in the case of a tetradecahedral particle, the A plane may be either the (111) plane or the [1001 plane, but the -most fl 00
The chemical enhancement nuclei on the + side are dot-shaped compared to the chemical enhancement nuclei on the [1111 side, and from the standpoint of controlling the location and number of chemical sensitization formations, it is preferable to place them on the fI O01 side.

Regarding the difference in the characteristics of chemically enhanced nuclei formed on the (1111 plane and +1001 plane), for example, E, Mo1
sar, S.P.S.E., Tokyo (1967),
E, Mo1sarBer, Bunsenges,
Phys, Chew,, 7 2 + P, 4
6 7-474 (1968) and G, C, Far
nell+ J, PhoL.

Sci., 23.249 (1975) may be referred to.

In addition, from the viewpoint of the number of A planes per particle, the first
As shown in the figure, in a tetradecahedral crystal close to an octahedral world, the number of A-planes is six, while in a tetradecahedral crystal close to a cubic crystal,
The number of A-planes is eight, and from the viewpoint of reducing the number of A-planes per particle, a tetradecahedral crystal close to an octahedral boundary is preferable.

It is preferable that the AgX particles of the present invention have a patented structure characterized by having at least +100} and {1111 crystal surfaces on the surface of one AgX particle and having different halogen compositions. Preferential in this case means (number of chemical sensitizations on crystal faces where chemical sensitization is preferentially formed/cffl) / (chemical sensitization on crystal faces where chemical sensitization is not preferentially formed) The number of impressions/1) is 2.
5 or more, preferably 5 or more.

It is difficult to directly observe this ratio. However, when a silver halide emulsion coating is exposed to light, a latent image is formed on its chemically sensitized result (photosensitive nuclei), suppressed development is performed, and the suppressed development nuclei are made visible by electron microscopy, and then the suppressed development is performed. The above ratio of chemical sensitization can be determined by counting the number of nuclei. Regarding this method, D. C.
Birch et al., Journal of Photogr.
aphic Science, Volume 2 3, P. 249
~256 (1975).

Here, the chemical enhancement nucleus is a chemical sensitization compound consisting of sulfur, selenium, tellurium, gold, and Group 8 noble metal compounds alone or in combination, and most preferably is a combined sulfur enhancement nucleus. It is usually called a sulfur sensitized nucleus, a gold sensitized nucleus, a noble metal sensitized nucleus, or a combination thereof, and for details, reference can be made to the literature mentioned below.

Furthermore, the inside of these particles is preferably reduction sensitized. Whether or not it has this reduction-sensitized silver nucleus is determined by
When wedge exposure is performed, internal development is carried out by a conventional method, and an HD curve is drawn, a reversal image of the existing internal fog is observed, so it can be easily determined.

The crystal structure inside the particle may be uniform, the inside and outside may have different halogen compositions, or it may have a layered structure. The halogen composition change between the eyebrows may be of a gradual increase type, a gradual decrease type, or a steep type, and can be used depending on the purpose of use.
The crystal structure described can also be referred to.

Further, the halogen composition change between the crystal surface layer and its interior may be of a gradual increase type, a gradual decrease type, or a steep type, but from the viewpoint of reducing the electron trapping property at the interface, is preferred.

The AgX grains used in the present invention are silver iodobromide and silver chloroiodobromide, and there are no particular limitations other than the aforementioned limitations on the halogen composition of the surface layer.

In the AgX particles of the present invention, the particle size distribution of the tetradecahedral particles is preferably narrow, and the coefficient of variation is preferably 20% or less, more preferably 5% or less.

In the AgX grains of the present invention, the grain size distribution of the tabular grains is preferably narrow, and the coefficient of variation is preferably 30% or less, more preferably 15% or less. Although the shape may be triangular or hexagonal, hexagonal tabular grains described in Japanese Patent Application No. 61-238808 and circular tabular grains described in Japanese Patent Application No. 62-203635 are more preferred.

The aspect ratio of the tabular grains of the present invention is preferably 1.0 or more, more preferably 1.5 to 16.

The AgX emulsion of the present invention has a crystal surface of at least (100) and +11 ml on the surface of one AgX grain, and is composed of AgX grains with different halogen compositions in the surface layer of the crystal surface, but these grains occupy The projected area ratio is preferably 70% or more of the projected area of all particles, more preferably 80% or more, and still more preferably 90% or more.

In particular, when an AgX emulsion with 14-hedral grains and a superhard gradation is preferred, it is preferable that the 3814-hedral grains of the present invention account for 98% or more, more preferably 99% or more of the projected area of all grains. It is particularly preferable that the coefficient of variation of the size distribution is 5% or less.

Next, a method for producing AgX particles of the present invention will be described.

First, a method for producing tetradecahedral grains will be described, and then a method for producing tabular grains will be described.

/, /4'hedral particles can be made by adding C, D, J, of an aqueous solution of A g N O 3 and an aqueous alkali solution of chloride in a gelatin aqueous solution, but C, D, in which 11-hedral crystals are formed.

The pBr (or pAg) region of J depends on the halogen composition during growth, the amount of coexisting AgX solvent, and the degree of supersaturation during growth. For more information on these please visit Murofush
International Congress
sof Photographic 5cienc
e, Tokyo (/riA7) J, Rodgers,
Symposium Paper on Growth
of Photosensitive crystal
s, Cambridge (/ri7r) T,
G. Bogg et al., J. Phot, Sci.

x p,, r t (/ri77) Akira Sasai, Nichishashi,
4'7 volumes.

Description of p, 211 (/r≠) and patent application 1982-col.
The reference example of Tata T-co (hereinafter referred to as application (A)) can be referred to. For example, in AgB r, the critical growth rate j
At supersaturation levels from 0 to %, pAg7, r! ~7. This is a reference area.

The (ll/) area and (ioo) area ratio of this /≠hedral grain can be changed depending on the pBr values of C, D, J, during crystal growth.
C, D, J at a potential close to the r value.

When added, a tetradecahedral product with a small area ratio of +1111 is produced.

In particular, the description in "Application (A)" can be referred to regarding how to prepare the AgX emulsion of the present invention in which the projected area of the dodecahedral grains is 98% or more, preferably 99% or more. To put it simply, the important point lies in the formation conditions.

In other words, it is preferable that nucleation be carried out under conditions in which twin planes are not formed.The frequency of formation of twin planes is determined by various supersaturation factors [temperature during nucleation, gelatin concentration, silver salt aqueous solution and alkali halide aqueous solution, etc. Addition speed, Br concentration, stirring rotation speed, aqueous alkali halide solution to be added? ■ in fft
-Content, halogenated iI? 8 Drug amount, pH, salt concentration (K
(N Os , Na N O2, etc.) depends on the molecular weight of gelatin, the presence of an antifoggant, etc., and this dependence is shown in the figure of Japanese Patent Application No. 6.1-238808 by the present inventors. Therefore, while looking at these dependencies, it is sufficient to move these conditional factors in a direction in which twin planes are not formed.

More specifically, while observing a replica image of the silver halide grains finally produced using a transmission electron microscope, the conditions for the supersaturation factor during nucleation may be adjusted to a direction in which twin planes are less likely to be formed. .

PAL of the reaction solution during particle formation can be 2 to 1O, but when introducing reduction-sensitized silver nuclei, it is 8.0 to 1O.
9.5 is preferred.

The concentration of AgXtl agent in the reaction solution is O~1.5
X I O-' mol/1 is preferable, and as the AgX solvent, those described below can be used.

Next, the surface layer of the (100) crystal surface of the AgX particle and the (
111) The following method is used to vary the halogen composition of the surface layer on the crystal surface.

Generally, a tetradecahedral crystal is formed under pgr of a cubic crystal formation head region,
When grown under low supersaturation, only the (111) plane grows. On the other hand, when a tetradecahedral product is grown at low supersaturation under the pAg of the octahedral crystal formation head region, only the [100) plane grows. Therefore, this characteristic is utilized.

In this case, p of the cubic crystal production region and the octahedral high production region
Regarding the Br region, the above-mentioned K.

Reference can be made to the description in the literature by Murofushi et al.

More specifically, for example, in the case of silver iodobromide grains having different halogen compositions in the surface layer, the method is as follows.

■ The entire surface layer forms tetradecahedral AgBrI grains with high iodine content, and then Ag with low iodine content under low supersaturation in the pAg in the octahedral high region or the pAg region in the cubic region.
The Br1 layer is crystal grown.

■ The entire surface layer forms tetradecahedral AgBr+ grains with low iodine content, and then Ag with high iodine content under low supersaturation in the pAg in the octahedral high region or the pAg region in the cubic region.
Br1ltiI is grown as a crystal.

In this way, tetradecahedral grains consisting of high iodine content crystal faces and low iodine content crystal faces are formed.

Further, in the above, the critical content between the low iodine content f# layer and the high iodine content layer may be of a gradual increase type, or the critical content of the halide salt added with in-situ gold crystal growth may be changed over time.

The total surface layer in this case means 50 grids, preferably 20 grids.
0 lattice thickness, and the degree of low supersaturation in these cases is 3-50% of the critical growth rate under those conditions.
, preferably at a rate of addition of 5 to 40% of the silver salt and halide salt.

To explain more generally, for example, when a tetradecahedral particle is placed in a solution of pAg in the cubic area, the cough (1001 plane and +1 plane)
The chemical p of each Ag' on the 111 plane
As shown in Figure 2, the relationship between
By adding a silver salt and a halide salt to this system, the chemical poten of Ag'' in the solution when 1 is
When the addition rate of silver salt and halide salt is increased, the supersaturation ratio (S) of the solution increases, and EA
, ◆ is △EA, ◆-kTJns (however, k-Bolt
zmanr+constant, T=absolute temperature). This is the driving force for crystal growth.
n+tcal potential difference, and this dr
If we focus only on the iving force, E16゜>
It is preferable to add the silver salt and the halide salt at a supersaturation ratio satisfying E ag''>E1□, which specifically corresponds to the above-mentioned addition rate.

In addition, when forming surface layers with different halogen compositions, it is undesirable if Ostwald ripening occurs between the layers, so the temperature at that time is preferably low. In this case, the preferable temperature range is 15 to 65°C, and Preferably it is 20-60°C.

It is also preferable to adsorb the above-mentioned adsorbent immediately after crystal growth to prevent Ostwald ripening between the eyebrows.

In addition, AgX with different halogen compositions in one AgX particle
AgX particles described in JP-A-55-124139 are examples of particles having a surface. This AgX particle is a particle in which AgX with a halogen composition different from that of the main body is precipitated in a part of the corner of the tetradecahedron, and as a result, a cubic crystal is formed.
A of the present invention is a particle having only the outer surface of 1001.
Different from gX particles.

In addition, as a method for producing AgX particles of the present invention, after adsorbing an adsorbent that preferentially adsorbs onto the - side crystal face, silver salt and silver halide are added, and the main body portion is placed on the other crystal face. It is also effective to precipitate AgX with a halogen composition different from the halogen composition.

Regarding the conventional method for forming tabular grains, see Japanese Unexamined Patent Application Publication No. 58-11.
No. 3926, No. 58-113927, and No. 58-
The description in No. 113928 can be referred to.

On the other hand, regarding a method for forming hexagonal tabular grains with good monodispersity, Japanese Patent Application Laid-Open No. 55-142329 and Japanese Patent Application No. 61-48950
No. 61-299155, No. 61-238808
You can refer to the description in the issue.

Usually, as mentioned above, the tabular grains produced in this way have a [1111 plane as the main plane and most of the edge faces, and the shape of the main surface is hexagonal (hereinafter referred to as a hexagonal tabular grain). , the particle size distribution is narrow.

However, after producing hexagonal tabular grains, if the crystals are subsequently grown in the cubic or tetradecahedral region (more specifically, in the case of AgBr, 9Ag8.0 or less), the grains become thicker. The main surface is a (111) plane, but the (100) plane begins to appear at the edges. Regarding this, reference example 1 can be referred to. If an AgX solvent is present at this time, this change will be further promoted.

Another method is to wash the emulsion with water to remove excess halogen present in the solution, or to remove the excess halogen present in the solution.
(100) can be added to the edge by double-jet addition of an aqueous solution of a silver salt and a halide salt.
A surface can be formed.

Excessive C in this case! -The concentration is pcj-0,7~
2.5 square range is preferred.

■After producing hexagonal tabular grains, when ripened under pAg in the cubic or tetradecahedral range, the edges (100
The first page is covered with rain. The progress of ripening at this time depends on the particle size of the tabular grains, the pBr of the solution, and the concentration of the AgX solvent, and this dependence is described in Japanese Patent Application No.
Tabular grains having (100) planes are produced on the shaded side of the curve in Figure 0, which can be referred to.

The obtuse angle of the edge of the tabular grain produced in this way is 125° when the edge is completely solidified (100), whereas that of the conventional tabular grain is 109.5°. .

After forming tabular grains having 00) planes at the edges in this way, halogens different from the substrate are formed on the (111) planes of these grains under pBr in the cubic island region and under low supersaturation. When AgX having the composition is laminated, the tabular grains of the present invention are produced.

The degree of low supersaturation in this case is the same as in the case of the tetradecahedral grains described above, and silver salts and halides are added at an addition rate of 3 to 50%, preferably 5 to 40%, of the critical growth rate of AgX grains under the conditions. Refers to the degree to which salt is added.

In the above-mentioned tetradecahedral grains and tabular grains, if AgX with a halogen composition different from that of the substrate is laminated only on one crystal plane, and if it is also laminated on the other crystal plane by mistake, then the cubic crystal By performing ripening in the region or the octahedral island region, the mistakenly stacked AgX layer is dissolved and deposited on one crystal face, making it possible to obtain the AgX particles of the present invention. At this time, the presence of AgX solvent further promotes the above-mentioned ripening.

In this way, at least (1
After forming AgX particles having crystal surfaces of 00} and {I L 11 and different halogen compositions in the surface layers of the crystal surfaces, chemical sensitization is performed to preferentially form particles on one crystal surface. There are two representative processes of chemical sensitization that preferably produce chemical sensitization.

■ Grain formation - Adsorption of adsorbent onto a specific crystal plane = (sulfur-rich gold) aggravation ■ Particle formation - (sulfur-rich gold) aggravation However, in the above process, the water-washing process of the emulsion may be performed anywhere after grain formation. That is, the water washing step may be carried out after particle formation, after the adsorbent has been adsorbed, between sulfur sensitization and gold sensitization, or after gold sensitization, or even once.
Even twice is fine.

First, the process (■) will be explained.

Immediately after grain formation or after washing the emulsion with water, it is preferable to add an adsorbent and allow the adsorbent to be adsorbed to the AgX grains. This is to prevent Ostwald ripening between crystal faces with different halogen compositions. It is also preferable.

As mentioned above, the adsorbent is preferably an adsorbent (which has different adsorbing powers depending on the halogen composition of the Al substrate) (an adsorbent which has different adsorbing powers for bl (111) and (100) crystal faces).

Specifically, such adsorbents were determined by examining the adsorption isotherm curves of various adsorbents on various AgX emulsion grains with the same grain surface area but different halogen compositions or crystal habits.
You can choose.

In this way, the above (a) or (al + (b)
Utilizing the selective adsorption characteristics of the adsorbent, the adsorbent is selectively adsorbed onto crystal faces where chemically sensitized nuclei are not preferentially formed.

- In boat fishing, the stronger the adsorption power, the more the sensitizing dye is J
Aggregates of J4 are more likely to form, and aggregates of J4 are preferred because they more effectively inhibit the formation of chemically sensitized nuclei.

Regarding the adsorption characteristics of adsorbents due to differences in the halogen composition and crystal plane of these substrates,
e Theory of the Photography
hic Process+Fourth Editio
n, Macmillan+ New York+ 1
977.

Chap, 9. Chap, 1. Chap, 13.

A, IIerz and J, Helling, J.
Co11oid InterfaceSci-+Main 2
, 391 (1966).

S, L, 5cruLLon, J, Phol S
ci, +22. 69 (1974).

J, Nys, Dye 5ensitizat
ion, Bressanone Sympos*
ulI+Focal Press, London
, 1 9 7 0. P, 2 6-4 3.57
~65°T, Dingani, Journal of I
imagining 5science, 2 5, 16
5 (1985).

Also, the description in the above-mentioned "Application (A)" can be referred to.

In addition, the adsorption power of aggravating dyes and additives to silver halide is
It is known that in addition to the crystal habit of the 5ubstrate and the halogen composition, it depends on various atmospheres of the emulsion (p of the emulsion, PAg, coexistence of adsorption promoters, etc.).

Therefore, use this knowledge to improve the adsorption strength of aggravating dyes and additives! You can write one verse.

For these, see, for example, T. Il. James,
The Theory of the Photographer
aphic Process, FourthEdit
ion, Mac+l1illan, New Year
k+ 1977, Chap, 9+Chap, 1.
Chap., 13 may be referred to.

Adsorbents include sensitizing dyes, antifoggants, stabilizers, and
The pendant dye (a compound chemically combined with an aggravating dye and an antifoggant or a stabilizer) described in the above-mentioned "Ex. III (A) J" is also effective.

As for the method of adding these adsorbents, only one type of sensitizing dye, antifogging agent, stabilizer, and pendant dye may be added, or a mixture of two or more types of additives may be added.
They may be added separately.

Further, the entire amount may be added before adding the chemical sensitizer, or 1 part may be added and the remainder may be added later, and 1 part is 1/10 to 1 of the total amount.

The amount of adsorbent added is not particularly limited, but is usually 0 to 120%, preferably 0 to 100% of the saturated adsorption amount of AgX particles.
It is.

In this way, after the adsorbent is selectively adsorbed onto one crystal face, a chemical sensitizer is added and ripened to form chemically sensitized nuclei preferentially on the other crystal face.

As the chemical sensitization method in this case, the following two chemical enhancement methods can be used.

[1] Commonly used chemical aggravation method (temperature of emulsion
A method of heating the temperature to 0° to 75°C, adding a sulfur sensitizer, adding a gold sensitizer 2 to 5 minutes later, and aging for 20 to 80 minutes)
Even if chemical aggravation is performed on one crystal face, the adsorbent is preferentially adsorbed on one crystal face, so almost no chemical aggravation nuclei are formed on that crystal face, and no chemical aggravation nuclei are formed on the other crystal face. Chemosensitized nuclei are preferentially formed.

[2] As a chemical sensitizer, a surface-selective chemical sensitizer that reacts selectively on a specific crystal face is used. Specifically, a surface-selective sulfur sensitizer that reacts selectively on a specific crystal face is used as the sulfur sensitizer. In the above case, it is preferable to use a sulfur sensitizer that reacts selectively on crystal faces that are not preferentially adsorbed by the adsorbent. (A)" and Reference Example 1 can be referred to.

For example, the emulsion conditions are pH 6.5, pAg 8.5.5
When aged at 0°C for 60 minutes, hypo reacts very selectively on the [1111 plane compared to the +1001 plane, forming sulfur-enhancing nuclei.

Triethyl Lhiourea reacts very selectively on the [1001 plane compared to the [111) plane, and
00) selectively forms sulfur-sensitized nuclei on the surface.

However, other conditions such as (pH 6.5, p, Ag8.
5.65°C 160 minutes) aging (pH 6.5, pAg 7
．． 7.50'C, 60 minutes) under aging conditions, its selectivity is small and therefore undesirable.Including other sulfur sensitizers, its surface selectivity is generally large under low temperature and high pAg conditions. .

In addition, in this case, if a gold sensitizer is added at the same time for chemical sensitization, the surface selective reactivity will decrease, so the above-mentioned "Out W4 (
A) Method J (method of adding gold sensitizer after performing sulfur aggravation, washing with water to remove residual sulfur sensitizer, or adding gold sensitizer after 80% or more of the added sulfur sensitizer has reacted, It is preferable to use a method in which a sensitizer is added.

In this way, effective chemical sensitizing nuclei are preferentially formed on one crystal face, and the AgX particles of the present invention are formed.

Furthermore, in the present invention, when AgBr+ with a high iodine content is used as the halogen composition of the surface layer of the B-plane, the chemically sensitized nuclei formed on the crystal plane are difficult to become effective electron traps, as described above. In this case, dl in the chemical sensitization process
As scris+1nat1on factor, (
It is particularly preferable because it has the advantage of being able to utilize the difference in crystal planes + difference in halogen composition and more effective discrimination.

Next, we will discuss the process (■). In this case, since there is no adsorbent that preferentially adsorbs on one crystal face, effective control of the formation position of chemical sensitizing nuclei is due to the reactivity of the chemical sensitizer (
Differences in crystal planes (differences in halogen composition of surface layer)
n is inferior to the process of ■.

However, compared to the conventional method (2) (difference in crystal plane), the difference in halogen composition of the surface layer is
Since it comes in as an onfactor, it has the advantage of being able to control the generation position of chemical sensitizing nuclei more effectively than conventional methods.

Regarding the chemical sensitization method of AgX particles of the present invention, reference may be made to the description in the amendment of Japanese Patent Application No. 61-299155.

The silver halide grains of the present invention can be used as an emulsion by themselves; however, a core/shell type direct inversion emulsion may be formed using the grains as a core, and this may be used. Example 13 of Japanese Patent Application No. 61-299155, and U.S. Patent No. 3,761,276,
No. 4,269°927 and No. 3,367.778 may be referred to.

Furthermore, a shallow latent type emulsion may be formed and used by using the particles as a core.
Reference may be made to British Patent No. 2, British Patent No. 145,876.

Alternatively, the particles may be used as host particles to form epitaxial particles.
No. 8526, No. 57-133540, Patent application 1986-1
No. 72966 may be referred to.

Further, the particles may be used as substrate particles to form Roughfuld particles. In this regard, reference can be made to US Pat. No. 4,643,966.

The tabular grains can also be used in high hardness systems.

Regarding this, please refer to JP-A-58-11392 Re5ear.
chDisclosure, Volume 184, August 1979, Item 18431, Section K may be referred to.

Moreover, until the gold sensitization aging of the particles is completed, H-0:
A method of adding an oxidizing agent such as a peroxy acid and then adding a reducing substance, or a method of reducing the amount of free gold ions in the sensitive material after gold sensitization and aging can be used. Regarding this, Japanese Patent Application No. 59-122981 and No. 59-12298
No. 4, No. 60-96237, No. 60-61429,
No. 60-61430, No. 61-184890, No. 6
No. 1-183949 may be referred to.

The tabular grains may be spectrally sensitized with an antenna dye.

Regarding this, Japanese Patent Application No. 61-51396, No. 61-2
The descriptions in No. 84271 and No. 61-284272 can be referred to.

Regarding the use of the optical coherence of the tabular grains, details of the above matters, and other matters, please refer to Japanese Patent Application No. 61
-299155 can be referred to.

In the ripening process of the present invention, in order to promote ripening,
Further, during this crystal growth period after ripening, a silver halide solvent may be used to promote crystal growth.

Examples of frequently used silver halide solvents include thiocyanates, ammonia, thioethers, and thioureas.

For example, thiocyanate (U.S. Pat. No. 2,222°264)
No. 2.448,534, No. 3゜320.06
9, etc.), ammonia, thioether compounds (e.g., U.S. Pat. No. 3,271,157, U.S. Pat. No. 3,574,6)
No. 28, No. 3,704.130, No. 4,297,
439, 4276.347, etc.), thione compounds (e.g., JP-A-53-144319, JP-A-53-8)
No. 2408, No. 55-77737, etc.), amine compounds (for example, JP-A-54-100717, etc.) can be used.

Sensitizing dyes used as the adsorbent and spectral enhancing dye of the present invention include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, and holopolar dyes.
Mention may be made of polymethine dyes including cyanine dyes, hemicyanine dyes, styryl dyes, hemioxonol dyes, oxonolmerosteryl and streptocyanine.

Specifically, /, /'-diethyl-2
, 2'-cyanine chloride, /
, / ', j, J'-tetramethy
l-,2,2'-cyanine, anionic termethylthiacarbocyanine j, j'-dimethyl
thiazolinodicar-bocyani
ne bromide, etc. For details, see the patent application No. 6/1977/No. 77≠/, t2-2/Tata ♂ No. 3, 2λ-
No. 231373 and the documents mentioned below can be referred to.

In addition, the above-mentioned [Application (A) JK described is a dandant dye (
Compounds in which a sensitizing dye and an anti-fog agent or a stabilizer are chemically bonded during their replacement period can also be used.

In addition, antifouling agents used as adsorbents, antifouling agents, and stabilizers include, for example, tetrazaindenes, azoles, such as benzothiazolium salts,
Nitroindazoles, Nitrobenzimidazoles,
Chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzimidazoles, aminotriazoles, benzotriazoles, nitrobenzotriazoles, mercaptotetrazoles (especially 1-phenyl-5-mercaptotetrazole), and mercapto Pyrimidines, mercaptotriazines, thioketo compounds such as oxacyrithione, as well as benzenethiosulfinic acid, benzenesulfinic acid, benzenesulfonic acid amide, hydroquinone derivatives, aminophenol derivatives, gallic acid derivatives, ascorbic acid derivatives, etc. I can do it.

As the sulfur sensitizer used in the present invention, in addition to the sulfur sensitizer of Reference Example 1, U.S. Patent No. 1.574.944,
Same No. 2,278,947, Same No. 2,410,689, Same No. 3,189,458, Same No. 3,501,313
Compounds such as those described in French Patent No. 2.059.245, or activated gelatin can be used.

There are no particular restrictions on other structures of the emulsion layer of the silver halide photographic material of the present invention, and various additives may be used as required.

Chemical sensitizers, spectral sensitizing dyes, antifoggants, metal ion dopes, silver halide solvents, stabilizers, dyes, color couplers, DIR couplers, binders, hardeners, coating aids, which can be added. Thickeners, emulsion precipitants, plasticizers,
Dimensional stabilizing agents, antistatic agents, optical brighteners, lubricants, matting agents, surfactants, ultraviolet absorbers, scattering or absorbing materials,
Hardening agents, anti-adhesion agents, photographic property improvers (e.g. development accelerators, contrast enhancers, etc.), developers, etc. Photographically useful fragments (development inhibitors or accelerators, bleaching accelerators, developers, silver halide solvents) , L-ners, hardeners, antifoggants, competitive couplers, chemical or spectral sensitizers and desensitizers, etc.), image dye stabilizers, self-suppressing developers, and uses thereof; Super-exacerbation in spectral sensitization, halogen acceptor effect and electron acceptor effect of spectral sensitizing dyes, effects of antifoggants, stabilizers, development accelerators or inhibitors, and other manufacturing equipment used to manufacture the emulsion of the present invention , reaction equipment, stirring equipment, coating, drying method, exposure method (light source, exposure atmosphere, exposure method), photographic support, microporous support, undercoat layer, surface protective layer, cloak agent, interlayer, antihalation. Regarding layers, photographic processing agents, and photographic processing methods, see Research Disclosure Magazine, Vol. 176, 1978, 1.
February issue (Item 17643), 184 @ August 1979 issue (Item 18431), 134S1975
June 2015 (Item 13452) Product Licensing Index Magazine Volume 92 107-110 (1971
(December 2013), JP-A-58-113926, JP-A No. 5B-1
No. 13927, No. 58-113928, No. 61-31
No. 34, No. 62-6251, JCIA Monthly Report 1984, 1
February issue, P, 11' 8-2 7 T, H, J
ames, The Theory of t
hePhotographic Process+F
ours Edition, Macmillan+
New York, 1977, V, L, E
elikman at al, authorMaking and
CoatingPhotographic Es+u
lsion (The Focal Press, 1
964) can be referred to.

The silver halide emulsion of the present invention can be provided in one or more layers (for example, two or three layers) on a support together with other emulsions, protective layers, intermediate layers, and filter layers, if necessary.

Moreover, it can be provided not only on one side of the support but also on both sides. Furthermore, they can be layered as emulsions with different color sensitivities.

Regarding this layer structure, please refer to JP-A No. 61-3134.
Reference may be made to the description in Japanese Patent Application No. 61-299155.

The silver halide emulsion of the present invention can be used in black-and-white silver halide photographic materials (e.g., It can be used for film, color paper, silver dye bleaching photographs, etc.). Furthermore, it can also be used for a photosensitive material 14 for diffusion transfer (for example, a color diffusion transfer element, a silver salt diffusion transfer element), a heat-developable photosensitive material (black and white, color), and the like.

(Effects of the present invention) The AgX particles of the present invention, in which the position and number of chemically sensitized nuclei on one AgX particle are controlled, have the following characteristics.

1. The formation of chemically enhanced nuclei is well confined on one crystal face. Therefore, a silver halide emulsion with less latent image dispersion, high sensitivity, and good development progress can be obtained. This effect is particularly important for particles with a particle size of 1.0 μm or more that cause latent image dispersion.
gX particles have a particularly large effect.

2. Compared to the method of controlling the formation position of chemically sensitized nuclei only by the dependence of the adsorption force of the adsorbent on the crystal plane, this method has the following advantages.

(i) The adsorbents that can be used (especially sensitizing dyes) were limited to surface-selective adsorbents, but now they can be used to utilize the difference in adsorption power due to the difference in the halogen composition of the surface layer. The range of adsorbents that can be selected is widened.

(ii) Strongly adsorbing adsorbents are more preferable to suppress chemically aggravated extrusion formation, but in general, surface-selective adsorbents are
The adsorption force was weak, and the two were contradictory requirements8.In the present invention, the adsorbent can be strongly adsorbed to the intended crystal surface because it also utilizes the difference in adsorption force due to the difference in the halogen composition of the surface layer. , the above problem has been solved.0 For example, a layer of AgBr1 with a high iodine content is used as the surface layer of the crystal, and AgBr or a layer of AgBr1 is used as the other surface layer of the crystal! When a layer is used, the adsorbent is strongly adsorbed on the surface of the AgBr1 crystal.

(iii) Since chemical ripening is carried out with the adsorbent strongly adsorbed, particle deformation during chemical ripening is small.

3. Site and color The site is generally an adsorbent (
If a large amount of sensitizing dye (sensitizing dye) is strongly adsorbed, the development suppressing effect becomes stronger, but in the AgX particles of the present invention, the latent image nucleus, which is the development starting point, is formed on the crystal face where the sensitizing dye is sparsely adsorbed. Therefore, its development inhibiting effect is small.

On the other hand, until now it has not been possible to adsorb large amounts of sensitizing dyes from the viewpoint of suppressing development, but since there are almost no latent image nuclei on the crystal planes that adsorb large amounts of sensitizing dyes, development can be suppressed. There is no need to worry about this, and a large amount of sensitizing dye can be adsorbed onto this crystal face, making it possible to achieve high negative blue sensitivity.

That is, the adsorption distribution of the sensitizing dye on the AgX particle surface is
The required amount of exacerbating dye is adsorbed to the necessary places, and only a small amount of exacerbating dye is adsorbed to the places where adsorption remains, resulting in photographic properties with high sensitivity and good development progress. .

4. In a preferred embodiment of the present invention, one crystal face has a high iodide content of iAgBrl as a surface layer, and the other crystal face has a low iodide content of AgBr1 or 8gBr, AgBrC.
1 as a surface layer, it has the following characteristics.

(i) Sensitizing effect due to dye holes Minus When exposed to blue light, the excited electrons of the dye are AgX
is injected into the conduction band of the iodine, is trapped by chemically sensitized nuclei on the low iodine content crystal plane, forms a latent image, and is positionally charge-separated from the dye holes.

On the other hand, the dye holes are injected into the high-tolerance content layer, react with the reduction sensitized nuclei in the high-tolerance content layer as follows, and release electrons.

Agz + regular bill - A g ” + A g = 2 A
g ” + e These electrons are trapped in the latent image nucleus and serve to increase photographic sensitivity.

Since the valence band of the highly saturated IT layer is located at a higher position, this dye hole injection is more efficient (injected into AgX, the above reaction is further promoted, and high sensitivity is achieved).

That is, the effect of preventing recombination by separating the latent image nuclei and dye holes, and the effect of increasing sensitivity due to the high conversion efficiency of dye holes to conduction electrons can be obtained. If this is represented by an energy level diagram of AgX and the dye, it will be as shown in Figure 3.

(ii) Effect of having a low iodine content crystal face and a high iodine content crystal face on one AgX grain
On the other hand, the adsorption of the dye increases, the color sensitization efficiency (if it is strongly adsorbed, the wave function overlap between the conduction band of AgX and the excited level of the dye becomes larger, and the A single layer with a high concentration is preferred from the viewpoints of high electron injection efficiency) and hole injection efficiency into AgX, and these two are contradictory requirements.

In the AgX particles of the present invention, in order to increase the initial development speed, the development start point (latent image nucleus formation position) is located on the low iodine content crystal face, and a large amount of dye is strongly adsorbed, increasing the color sensitization efficiency. In order to improve the performance, the dye adsorption crystal surface has a high content of iAgX, which satisfies both of these contradictory requirements.

5. Blue and generally speaking, the magnitude of blue light absorption of AgX emulsion grains is
C1<AgB r<Ag E, and on the other hand, the development progress is Ag Cj! >AgBr>Ag I, and satisfying both is a contradictory requirement.

However, in the AgX particles of the present invention, the latent image nucleus, which is the starting point for development, is located on the low iodine content crystal plane, and there is no problem in terms of development speed. Since the crystal plane can have a high content of AgBr1, there is no problem and both requirements can be satisfied.

The thus obtained photographic material comprising AgX grains of the present invention provides a silver halide emulsion excellent in sensitivity, development progress, graininess, reciprocity properties, sharpness, resolution, gradation, and image quality.

Preferred embodiments of the invention are as follows.

1) An AgX emulsion characterized in that 70% or more, preferably 80% or more, more preferably 90% or more of the projected area of all AgX grains consists of the AgX grains according to claim 1 or 2.

2) (Number of chemically sensitizing nuclei on the crystal face where chemically sensitizing nuclei are preferentially formed/J) / (Chemically sensitizing rf on the crystal face where chemically sensitizing nuclei are not preferentially formed!, Nuclei number/-) is 2.5
Silver halide emulsion 3) +L L Area of 11 planes/(average value of area of 1001 planes is 20 to 1/20, preferably 1O to 1/10)
The AgX emulsion according to claim 1.2, characterized in that it consists of tetradecahedral grains.

4) (Area of 1111 planes/Area of +1001 planes) consists of tabular grains having parallel twin planes having an average value of 20 to 1.01, preferably 15 to 2.0. AgX emulsion described in Section 1.2.

5) [1002 and il 11) The halogen composition of the surface layer on the crystal surface differs from each other by 2 to 40 mol%, preferably 3 to 30 mol%, and the chemical sensitizing nuclei are different from each other in the low iodine content surface. A according to claim 2, characterized in that it is preferentially formed on a crystal surface having a layer.
gX emulsion.

6) AgX according to claim 2, characterized in that the surface layer of the crystal surface where chemically aggravated nuclei are preferentially formed has a normal content of 5 mol% or less, preferably 3 mol% or less
emulsion.

? ) +1001 and (1111) A crystal surface in which the halogen compositions of the surface layers of the crystal surface differ from each other by 7 to 100 mol%, preferably 10 to 80 mol%, and the chemical sensitizing nuclei have a high C1 content layer. AgX according to claim 2, characterized in that it is preferentially formed on
emulsion.

8) Using the difference in effective chemical sensitization nucleation ability due to (differences in crystal planes and differences in halogen composition of the surface layer) AgX emulsion grains produced by the method of claim 4, one A method for producing an AgX emulsion, characterized by forming effective chemically enhanced nuclei preferentially on crystal faces.

9) In the AgX emulsion produced by the method according to claim 4, on the crystal face on which chemical sensitization nuclei are not formed preferentially,
A method for producing an AgX emulsion, which comprises adsorbing an adsorbent preferentially by utilizing the differences in crystal planes and the halogen composition of the surface layer, followed by chemical sensitization.

The present invention will be further explained with reference to Reference Examples and Examples below.

Reference Example 1 Gelatin aqueous solution (water 1
000-, gelatin 7 g, K13 r 4.5 g.

pH 8,0) and keeping the solution temperature at 30°C,
AgN0. 25 d of aqueous solution (containing 8.0 g of AgNOt) and 25 d of KBr aqueous solution (5.8 g of KB r
) were simultaneously added over a period of 1 minute (flow rate 25-7 minutes), and after stirring for 1 minute, 350- of them were used as seed crystals,
Add gelatin aqueous solution (650 g of water, 20 g of gelatin)
, KB r 0.5 g, pH 8,0) and the temperature is raised to 75°C. After raising the temperature and aging for 45 minutes, A
gNOs aqueous solution (30g AgNOs in 100TR1
) and KBr aqueous solution for the first 10 minutes, 13-7 minutes for the next 20 minutes, pBrl, 8
(However, in this case, including Br- adsorbed on AgX particles,
The excess amount of KBr present in the AgX emulsion is 1.6 g/f
The silver potential was -15 mV. ) During the next 20 minutes, C, D, and J were added at 20-7 minutes.

A is (-4mV), B is +10mV, C is +40mV,
D was +70mVSR was +100mV C, D, and J were added. (100) of the obtained AgBr tabular grains
When the area ratio of the surface is determined using the method of T and Tan1 described above,
A (9%), B (9.6%), C (15.5%),
D (25%), E (58%), C, D, J, 1
As the number one rank increased, the (100) area ratio of tabular grains increased.

A gelatin aqueous solution [water 1
000d, deionized alkali-treated gelatin 30g5K
BrO, 5g-NHaNOsl g1NH3 (25% by weight)
An aqueous gNOs solution and an aqueous halide solution were added. Ag
N0. The addition rate was 3.3X l for the first 10 minutes.
O-'M7win, double-jet addition of AgN0° aqueous solution and KBr aqueous solution was carried out. The pBr value during addition is 2
．． The zero-order addition rate was 53.6. OX 10-'M/
win, AgN0. for 7 minutes. After adding the aqueous solution and the KBr aqueous solution, continue at an initial addition rate of 6.0X 10-'M/
sin,, final addition rate 8×10-”M/a+in,
pAg 7.7f)C,D by linear accelerated addition method for 85 minutes
, J, was added. The sealing distance between the (111) faces of the tetradecahedral particles (hereinafter referred to as fiE1) obtained at this point is 0.
90 μm, (1111 area was 17%).

Next, after adding kBr to make pAg 8.6, initial addition rate 1.5X 10-'M/win, final addition rate 2X
10-'M/sin,, with an addition time of 20 minutes, AgNO
s aqueous solution with Kl content of 6 mol% (KB r + K I)
Aqueous solutions were added to C, D, and J with a pAg of 8.6. The distance between the (///) faces of the /≠hedral particles obtained at this time is θ, P
There was no bulkiness at θ μm as above, and the added AgBrI (4
(mol%) indicates that only the (ioo) plane of the monohedron was laminated.

The temperature of this emulsion was lowered to 300C, washed with water, redispersed, pAgr, l=, pHA, j, temperature≠o
'C 1. ? , J'-bis (4'-5u
lfobutyl)-tar methylthiaca
After adsorbing 7% of the saturated adsorption amount of rbocyanine dye, the emulsion conditions were changed to pAgf, 4, pHA, j
, set the temperature to j00c, and set the temperature to N a S O-j H20
Add only 1 mol AgBr t” '-2×IO mol, and after a 3 minute delay add gold sensitizer (gold thiothia/ugly complex) tl-0,3×
10 mol of AgBr was added and aged for 70 minutes.

The temperature was set to ≠o 'C and the antifoggant (TAI ('I-
hydroxy-A-methy+-/, j,
ja.

1.5 g/rl of silver was coated onto the transparent base with the addition of 3 g (1 mole Ag) coating aid.

Odachi ■ Example 1 is the same except that the dye is adsorbed onto the tetradecahedral grains, and the emulsion conditions are pAg 8.6, pH 6.5, and temperature 50°C. 9X
After adding 10-' 1 mol AgBr and aging for 40 minutes, the aforementioned gold sensitizer was added at 0.3X 10'' mol 1 mol AgBr, and the mixture was aged for another 40 minutes. Add anti-fogging agent, coating aid,
ill, 5 g/n (coated on a transparent base).

For comparison, the process is the same as in Example 1 up to the point where AgX particles of El are made. After adding KBr to the zero order and making p A g 8.6,
Initial addition rate 1.5X 10M/min, final addition rate 2X 10-"M/ll1n, addition time 20
AgN0° aqueous solution and KBr aqueous solution with pAg8.6 C, D, J.

Added. The sealing distance between the (111) faces of the tetradecahedral particles obtained at this time was 0.9 μm, indicating that the added AgBr was deposited only on the (100) face of the tetradecahedron. After this, the same steps as in Example 1 were carried out.

The emulsion coatings of Examples 1 and 2 and Comparative Example 1 were exposed to blue light for 1 second (the exposure dose was 10 times the exposure dose that gave the maximum density), and the coatings were incubated at 20° C. with the aforementioned suppressing developer of Birch et al. After developing for 6 minutes, the gelatin was removed and a TEM image of the particles was observed using a replica method. Table 1 shows the percentage of development start points of 0 particles present on the +111) plane of the tetradecahedral particles.

The emulsion coatings of Example 1.2 and Comparative Example 1 were also wedge exposed for 10-'' seconds through a blue filter, and MA
It was developed with A-1 developer at 20°C for 10 minutes. The relative quantum sensitivities determined from the obtained characteristic curve and the light absorption rate of the AgX particles are shown in Table 1, and the effect of the present invention on Comparative Example 1 was expressed as u'ffl t=.

Table 1 Aqueous gelatin solution (water 1
000ad, gelatin 7 g, KB r 4.5 g.

pH 8.0) was added, and while maintaining the solution temperature at 30'C, AgN0. Water-soluble t&25mff1 (A g N
(contains 38.0 g of O) and 25 d of KBr aqueous solution (KB
r containing 5.8 g) at the same time for 1 minute (flow rate 2
5-7 minutes) and stirred for 1 minute, then 300
- as a seed crystal, and add thereto an aqueous gelatin solution (650 m of water, 720 g of gelatin, 0.6 g of KBr, pH 8,
0) and raise the temperature to 75°C. After raising the temperature and aging for 45 minutes, a AgNo3 aqueous solution (10 (40
g(7)AgNO,) and a KBr aqueous solution,
6-7 minutes for the first 10 minutes and 12-7 minutes for the next 20 minutes.
At 7 minutes, pBrl, 7 C, D, J, was added.

Then C, D, J at pAg 6.8 for 7 min at 6-7 min.

Added. The tabular grains obtained at this point were
Using Tan1 method (1001 area ratio is calculated as 20
%Met. The average particle size was 1.1 μm.

Then 6.1 layers for 7 minutes, pA g 6.5teA g
NOx aqueous solution and legal content of 6 mol% (KBr+Kr)
Aqueous solution was added. The average grain size of the finally obtained tabular grains was 1.1 μm, which was the same as above. Therefore, it can be seen that AgBr1 (6 mol %) was laminated only on the [1111 principal plane. The tabular grains have an average aspect ratio of 6 and a coefficient of variation of the projected grain size of the tabular grains of 15.
It was %.

The AgX emulsion thus obtained was washed with water, redispersed, and the emulsion was adjusted to pH 6.5, pAg 8. o, set the temperature to 40℃,
3* 3'-dimethylthJazoli
Nodicarbocyanine bromide dye was added in an amount of 80% of the saturated adsorption amount, and the pAg was adjusted to 8.0. After incubating for 20 minutes, pAg 8.5 Temperature 5
At 0°C, a methanol solution (0,005% by weight) of Trlathy and thlouraa was added to 1. OX 10'' mol 1 mol AgBr was added and after a delay of 3 minutes, the aforementioned gold sensitizer was added in 0.4× 10'' mol 1 mol AgBr and further aged for 40 min. The temperature was increased to 40°C. Lower it to
An antifoggant and coating aid were added and coated onto a transparent base.

In Example 3, one layer of AgBr to be laminated later was
An AgX emulsion was prepared in which all other conditions including chemical sensitization were the same except that gBr was replaced, and an antifoggant and a coating aid were added and coated on a transparent base.

Next, the emulsion coatings of Example 3 and Comparative Example 2 were compared in the same way as in Table 1, and the results are shown in Table 2. The effect of the present invention on Comparative Example 2 was confirmed.

Table 2 Sm Emulsion A of Reference Example 1 (average projected grain size 1.35 μm) was 0
．． Gelatin aqueous solution containing 22 mol (11 water, 20 gelatin)
g, KB r O, 3 g, pH 6,0) were placed in a 41 reaction vessel, the temperature was brought to 75 °C, and the N H4
Added 3 g of N03, 60% of NH3 water (25% by weight), and added 2 minutes diameter km of AgNO3 aqueous solution (10 in
containing 0g of AgNO3) and KBr aqueous solution at a silver potential of +4
C, D, J were added at 0 mV for 40 minutes. The initial flow rate is 3.9-7 minutes and the final flow rate is 13-7 minutes of linearly accelerated addition. After 1 minute, add 2 HNOs (3N) solution.
8-Added. The average projected grain size of the tabular grains at this point was 1.45 μm.

Next, A g N Os aqueous solution (log A in 100-
g N Os) and with a Kl content of 6 mol% (KB
r+KI) aqueous solution at 2.5 m/min for 30 minutes, silver potential 1
Added at 20 mV. The temperature was lowered to 30°C and the emulsion was washed with water and redispersed. The average projected grain size of the tabular grains at this point was 1.45 μm.

Therefore, the finally added AgBr1 was not deposited on the edges of the tabular grains (Fig. 4 shows the shape of the edges of this grain, indicating that it was laminated on the main surface of 1111).
(21,000x magnification), (12
This indicates that the grains are tabular grains having (100) edge faces with an obtuse angle of 5°. The average (100) area ratio was 30%.

A gelatin aqueous solution containing 0.26 mol of emulsion A of Comparative Example 1 (containing water I II, 15 g of NaF-20 g of gelatin) was placed in a reaction vessel No. 41, the temperature was set to 75°C, and Ag
NO3 aqueous solution (including AgN0!Log in 100-)
and (KB r +Na C
l1) Using an aqueous solution, the initial flow rate is 4.0 a! /min, final flow 1t20ad/min linearly accelerated addition, p C1-1
,07. The temperature was lowered to 30°C and the emulsion was washed with water and redispersed. The average projected grain size of the tabular grains at this point was 1.30 μm, and the added Ag
BrC1 indicates that the film was laminated only on the (1111 main surface) of the tabular grain.

The shape of this particle is shown in Figure 5 (magnification: 19,000 times), (1111) indicating that it is a tabular grain with a fl O01 face having an obtuse angle of 125°C with respect to the main surface. +1001 area ratio was 50%.

In a reaction vessel having a volume of 42 ml, gelatin aqueous liquid [water 1 ml] was added.
000TR1, gelatin 30g, KBro, 5g, N
2m of Hs (25% by weight)! ,,N HaNOs (5
0% by weight) 2-], and while maintaining the solution temperature at 60°C, add 0.9% AgNO° in an AgNOs aqueous solution (100°C).
(containing 3 g) and a halogenated salt aqueous solution were added.

The AgNOx addition rate was 3.3 for the first 10 minutes.
x 10-'M/min, then 8.9X 10-' for the next 9 minutes
'AgN0.M/min. The liquid and (KB r +K I) aqueous solution (KI content: 6 mol %) were added by double jet.

The pBr value during the addition was 2.4.

Next, initial addition rate 9. C, D, and J were added at a silver potential of 125 mV using a linear accelerated addition method of OX 10-"M/min, a final addition rate of 7.8X 10-"M/min, and a period of 60 minutes.

The tetradecahedral particles obtained at this point were as shown in FIG. 6a.

Next, set the position of 111 to +170mV, and set A g N O
J liquid (contains 510g of AgN in 100-) and KBr
Using a linear acceleration addition method for 20 minutes, using a liquid with an initial addition rate of 1.8X 10-'M/min and a final addition rate of 3.25X 104M/min. ! C, D, and J were added at a potential of 18 OmV. The tetradecahedral particles obtained at this point were as shown in FIG. 6b.

The edge lengths of both tetradecahedral particles were both 0.63 μm, indicating that the AgBr added last was precipitated only at a portion of the corners of the tetradecahedron. (100) area of this particle determined from TEM image: (111) plane fl-15:8
It was 5.

This emulsion contains 3. 3'-bis(4-5ulfob
-9-5ethylthiacarboc
After adsorbing 75% of the saturated adsorption amount of yanine dye, the emulsion conditions were pAg 8.6, pH 6.5, and temperature 50°C.
and NatsxOs ・5H1O to 0.9 x 10
``'1 mol AgBr was added, and after 3 minutes, a gold sensitizer [gold-thiocyanate complex] was added in an amount of 0°3 x 10-5 mol 1 mol AgBr, and the mixture was aged for 70 minutes.The temperature was set to 3!
Lower the temperature to 0C, wash the emulsion with water, redisperse it, and adjust the emulsion to pHj
, j, pAgr, jK1 section.

Adjust the temperature to ≠00C, add antifouling agent and coating aid, and silver/! g/yn2 coated on a transparent base.

Comparative Example 3 The procedure of Example 6 was repeated until the AgX particles shown in FIG. 6a were made. Next, the silver potential was set to 10 OmV, and the AgNO3 solution (l
Using a KBr solution containing 310 g of AgNO3 in ooml, the initial addition rate was i, rX 10-3 M/min, the final addition rate was 3.2j C, D, and J were added. The shape of the nta/≠hedral particle obtained at this point is 7 in Figure 6a.
The AgBr added last, which has a shape almost similar to the proporhedral particles, is uniformly layered on almost the entire surface of the protrusive particles, indicating that they are so-called 2ffi-structured particles with a high internal rigidity.

This emulsion is washed with water and redispersed; 3. 3-bis(4
-5ulfobuLyl) -9-methylthi
After adsorbing 75% of the saturated adsorption amount of acarbocyaninedye-f, the emulsion conditions were changed to pAg 8.6 and pH 6.
, 5. The temperature was set to 50°C, and Nazsto* 5 HzO
Add 1.5X 10-'mol 1 mol AgBr, 3
After a minute delay, add 0.5
Only molar AgBr was added and aged for 60 minutes.

The temperature was then lowered to 40° C., an antifoggant and a coating aid were added, and the coating was coated onto a transparent base at 1.5 g/rd of silver.

Next, the emulsions of Example 6 and Comparative Example 3 were compared in the same way as in Table 1, and the results are shown in Table 3. The effect of the present invention on Comparative Example 3 was confirmed.

Table 3

[Brief explanation of the drawing]

Figure 1 schematically shows the position where chemical sensitization occurs, and ial is for the case of a tetradecahedral particle close to a cube;
(bl indicates the case of a dodecahedral particle close to an octahedron. Figure 2 shows the chemical potential of the (100) plane and (111) plane in a cubic atmosphere in the method for producing AgX particles of the present invention. FIG. 3 is a schematic diagram showing the relationship between the chemical potential of the ion in the particle. FIG. Coordinates are shown, black circles indicate electrons and white circles indicate holes. Figures 4 and 5 show the Ag prepared in Examples 4 and 5.
The zero magnifications of the electron micrographs showing the resulting structure of X are 21.000x and 19°000x, respectively. Figure 6 schematically represents the structure of AgX in Example-6.
shows dodecahedral grains in which AgX with different halogen compositions are grown on host grains.

Claims (1)

[Scope of Claims] 1) A silver halide emulsion consisting of a dispersion medium and silver halide grains, which accounts for 70% of the projected area of all silver halide grains.
At least {10
A silver halide emulsion having crystal surfaces of {0} and {111}, wherein the halogen compositions of the surface layers of the crystal surfaces are different from each other. 2) The silver halide emulsion according to claim 1, wherein chemically sensitized nuclei are preferentially formed on one crystal face. 3) The halogen compositions of the surface layers on the {100} and {111} crystal surfaces differ from each other by 2 to 40 mol% in iodine content, and the chemical sensitized nuclei are on the crystal surface having the low iodine content surface layer. 3. The silver halide emulsion according to claim 2, wherein the silver halide emulsion is preferentially formed as follows. 4) At least {100
} and {111} crystal surfaces are placed on one of the {100} or {111} crystal faces under low supersaturation in the octahedral pAg or cubic pAg region. 1. A method for producing a silver halide emulsion, which comprises growing crystals of silver halide having a halide composition different from that of silver halide grains as a substrate.