JPH08262617A - Production of internal latent image type direct positive silver halide emulsion and color diffusion transfer photographic film unit using this emulsion - Google Patents

Abstract

PURPOSE: To provide a method of producing a parallel twin crystal containing type flake core/shell emulsion with a high S/N ratio, and heighten the sensitivity of a color diffusion transfer photographic film by using this emulsion, while lowering minimum density. CONSTITUTION: In a method of producing a parallel twin crystal containing type flake core/shell emulsion in which the thickness of 75%-100% of the total projected area of all grains is 0.03-1.0μm and the aspect ratio is 2-50 through nucleation, curing and growth processes, 30-100wt.% of a dispersion medium in a part or the whole of grain forming process is formed of gelatine with such a characteristic that the relation between the ratio (%) of the chemically modified number of -NH2 radicals in gelatin and the methionine content of gelatin is in an a1 area.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an internal latent image type direct positive silver halide emulsion which has not been previously covered, and a color diffusion transfer photographic film unit using the emulsion.

[0002]

2. Description of the Related Art Generally, in the case of a core / shell direct inversion emulsion, preparation and chemical ripening of core grains are followed by addition of a silver salt solution and a halogen solution to laminate silver halide on the core grains (shell attachment). It is prepared). In such a preparation, a parallel twin-containing tabular core / shell direct inversion emulsion is preferred in order to obtain high sensitivity. At that time, the photographic characteristics are changed by the variation of the shell thickness, and in order to achieve a high S / N ratio, the uniformity of particles (and thus the uniformity of the shell thickness) has been strongly desired. When a parallel twin crystal-containing tabular silver halide emulsion is used as the core / shell direct reversal emulsion in a color diffusion transfer photographic film unit, the photosensitive layer of the photosensitive material can be made thinner. For this reason, it is possible to improve the sharpness of the photosensitive layer itself and the sharpness of the transferred image at the time of diffusion transfer. Further, since the surface / volume ratio of the particles is larger than that of the normal crystal particles, more sensitizing dye can be adsorbed and the color sensitizing sensitivity is improved. Therefore, graininess is also improved. Therefore, there is an advantage that the color diffusion transfer photographic film unit can have high sensitivity and high image quality. Parallel twin-containing tabular core / shell direct inversion emulsions are described in US Pat.
504,570, JP-A 1-297,649, 1
No. 158,429, the tabular grains prepared by the well-known preparation method have insufficient monodispersity, and they cause unevenness in shell thickness, which makes it impossible to achieve high contrast. Furthermore, in order to prepare an internal latent emulsion, it is necessary to coat the chemical sensitization site with a shell thickness of a certain value or more,
This inevitably requires shell attachment and growth in the thickness direction, and in order to realize an internal latent emulsion with a high aspect ratio, a method for forming monodisperse high-aspect grains of core grains has been strongly desired. So far, attempts have been made to monodisperse tabular grains, and Japanese Patent Application No. 6-184158 discloses a grain forming method with improved monodispersity. However, the examples are so-called negative type and there is no description of autopositive emulsions.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to prepare a core / shell direct inversion emulsion in which a high S / N ratio is realized by a method for producing monodisperse high aspect grains in the preparation of the core / shell direct inversion emulsion. And to provide a color diffusion transfer photographic film unit using the same.

[0004]

The objects of the present invention are as follows (1)
The problems are solved by the core / shell type direct inversion silver halide emulsion described in (6) to (6) and the color diffusion transfer photosensitive unit using the same. <1> In a dispersion medium solution containing water and a dispersion medium, 75-100% of the total projected area of silver halide grains has a thickness of 0.03-1.0 μm through at least nucleation, ripening and growth processes.
m, an aspect ratio (diameter / thickness) of a tabular grain having a core / shell type direct inversion emulsion of 2 to 50, wherein 30 to 100 of the dispersion is used in a part or all of the silver halide grain formation process. A method for producing an internal latent image type direct positive silver halide emulsion which has not been previously fogged, characterized in that the weight% is gelatin having the following characteristics (a). (A) The relationship between the percentage (%) of the number of chemically modified --NH ₂ groups in the gelatin and the methionine content of gelatin is in the region a ₁ of FIG. <2> The dispersion medium solution is a polymer having repeating units of polyalkylene oxide and has a molecular weight of 500 to 10 ⁶ HPAO [represented by general formula (1) -a] or (1) -b). Or PEOD [general formula (2) -a) to-
f) is contained in an amount of 0.001 g / liter or more and 100 g / liter or less <1
> The method for producing a silver halide emulsion as described above.

[0005]

[Chemical 4]

R ⁰ is H or a hydrocarbon having at least one polar group and having 1 to 10 carbon atoms, preferably H. R represents an alkylene group having 3 to 10 carbon atoms. n and m represent the average number of repeating units and are values of 4 or more satisfying the above-mentioned molecular weight regulation.

[0007]

Embedded image

Here, LPU means a lipophilic group other than the HO-HPEOU- group and the HO-LPAOU- group, and includes a substituted or unsubstituted alkyl group, alkenyl group, aryl group,
A heterocyclic group, an alkoxy group, an aryloxy group, an acyl group, an acylamino group, an alkylthio group, an arylthio group, an alkoxycarbonyl group, an aryloxycarbonyl group, and an alicyclic group. In addition, HPEOU, L
PAOU has the same meaning as in formula (1). <3> The dispersion medium solution contains 0.01 g / liter or more and 100 g / liter or less of at least one kind of polymer containing 1% by weight or more of the repeating unit of the monomer represented by the general formula (3). The method for producing a silver halide emulsion as described in <1>, wherein the combined molecular weight is 500 to 10 ⁶ .

[0009]

[Chemical 6]

R in the formula¹Represents H, a lower alkyl group, R
²Represents a monovalent substituent. R³Is an alkane having 3 to 10 carbon atoms
Represents a xylene group, and L represents a divalent substituent. n is repeated
It represents the average number of units and is 4-600. <4> The dispersion medium solution is a monomer represented by the general formula (3).
And at least 2 of the monomers represented by the general formula (4).
0.01% of a copolymer containing 1% by weight or more of each seed
g / liter or more, and the molecular weight of the copolymer is 500 to 1
0⁶<1> The silver halide milk as described in <1>,
Method of manufacturing agent. General formula (4) CH₂= C (R^Four) -L '-(CH₂CH₂O)_m-R^Five Where R^FourRepresents H, a lower alkyl group, R^FiveIs monovalent
It represents a substituent, and L'represents a divalent linking group. m is repeated
It represents the average number of units and is 4-600. <5> The dispersion
The medium solution contains a single repeating unit represented by the following general formula (5).
At least one polymer containing at least 1% by weight, and
Weight containing 1 wt% or more of the repeating unit represented by (6)
0.01g / liter or more 100g /
Contains less than liters, the molecular weight of each polymer is 500 ~
10⁶<1> The silver halide described in <1>
Emulsion manufacturing method. General formula (5)-(RO)_n-General formula (6)-(CH₂CH₂O)_m-In the formula, R represents an alkylene group having 3 to 10 carbon atoms.
I forgot. n and m represent the average number of repeating units.
It is a value of 4 or more that satisfies the requirement. <6> Heavy having a repeating unit represented by the general formula (5)
The united component is a monomer of the following general formula (7)-(a)
A vinyl polymer and a poly of the general formula (7)-(b)
Is at least one polymer selected from urethane,
A polymer having a repeating unit represented by the general formula (6) is
A monomer represented by the following general formulas (7)-(c) is used as a constituent component.
Vinyl polymer, polyurethane of the general formula (7)-(d),
And from substituted or unsubstituted polyethylene glycol
Characterized by being at least one polymer selected
<1> The method for producing a silver halide emulsion according to <1>. General formula (7) -a) CH₂= C (R¹) -L- (RO)_n-R² General formula (7) -b)-[O- (R-O)_n]_x− ・ − [O-R¹¹-O)_y− ・ − [CONH-R¹²-NHCO] _Z -General formula (7) -c) CH₂= C (R^Four) -L '-(CH₂CH₂O)_m-R^Five General formula (7) -d)-[O- (CH₂CH₂O)_m]_{X '}− ・ − 〔O-R¹³-O]_{y '}− ・ − [CONH-R¹⁴-NHCO]_{Z '} -In the formula, n and m represent the average number of repeating units and are 4 to 600.
Is. R¹, R^FourIs H or a lower alkyl having 1 to 4 carbon atoms
Represents a kill group. R², R^FiveIs H or has 1 to 20 carbon atoms
It represents a monovalent substituent. L and L'represent a divalent linking group.
R¹¹, R¹²Represents a divalent linking group and has 1 to 20 carbon atoms.
Ruylene group, phenylene group having 6 to 20 carbon atoms, or charcoal
It represents an aralkylene group having a prime number of 7 to 20. x, y, z,
x ', y', z'represent the weight percentage of each component, x,
x'is 1 to 70, y and y'is 1 to 70, and z and z'are 20.
Represents ~ 70. Where x + y + z = 100, x '+ y'
+ Z '= 100. R is an alkyle having 3 to 10 carbon atoms
Represents a group. <7> At least one dye image forming substance on a support
Combined at least one silver halide emulsion layer
A photosensitive sheet having the same, and 2. the photosensitive sheet and a second support
Alkaline treatment composition to be developed between
In a color diffusion transfer photographic film unit containing objects
And at least one of the silver halide emulsion layers is <1>.
To <6>, the internal latent image type rectilinear body not pre-fogged
Coloring characterized by containing a positive-contact silver halide emulsion
-Diffusion transfer photographic film unit.

The present invention will be described in more detail below. A. Tabular grains The tabular grains are tabular grains whose principal planes are {100} planes (hereinafter,
Examples thereof include "(100) tabular grains" and tabular grains having {111} faces (hereinafter referred to as "(111) tabular grains"). The tabular grains have a thickness of 1.0 µm or less and 0.03 µm or more, preferably 0.5 µm to 0.1 µm.
Is. The aspect ratio (diameter / thickness) is 2 to 50, preferably 3 to 30. The variation coefficient (standard deviation of distribution / average diameter) of the diameter distribution is preferably 0 to 0.3, and 0 to 0.
2 is more preferable. Here, the diameter refers to the diameter of a circle having an area equal to the projected area of a grain, and the thickness refers to the distance between two principal planes of tabular grains. Particle diameter is 0.1 μm
The above is preferable and 0.2-10 micrometers is more preferable. The tabular grains account for 75 to 100% of the total projected area of AgX grains,
Preferably 90 to 100%, more preferably 97 to 10
It accounts for 0%. The variation coefficient (standard deviation of distribution / average thickness) of the thickness distribution of the tabular grains is preferably 0 to 0.3, and 0 to 0.3.
0.2 is more preferable, and 0 to 0.1 is further preferable.

The tabular grains are manufactured through at least the steps of nucleation → ripening → growth. The nuclei of the finally obtained tabular grains are substantially formed in the nucleation process. Here, “substantially” means a number, preferably 75 to 100%, more preferably 95 to 100%. When the modified gelatin is used in the process of nucleation and ripening, the pH of the reaction solution is preferably a pH equal to or higher than the isoelectric point of the modified gelatin.
+0.2) to pH 10 is more preferable, and (isoelectric point pH +
0.4) -pH 7 is more preferable. The amount of AgNO ₃ added at the time of nucleation is preferably 1 g or more, more preferably 1.8 g or more, still more preferably 3 to 30 g, per liter of the reaction solution. Nucleation is performed by Ag ⁺ liquid and X ^{− in the} reaction solution.
It is more preferable to perform the simultaneous mixed addition method of liquids or the plural alternating single jet addition method of 2 to 1000 times. Next, the description will be made in order from (100) tabular grains.

A-1. (100) Tabular grains 1. Grain structure When tabular grains whose main plane is the {100} plane are classified by shape, the following six can be listed. (1) The shape of the principal plane is a right-angled parallelogram and within one tabular grain (long side length /
(Length of short side) is 1 to 10, preferably 1 to 3 particles, more preferably 1 to 2 particles, (2) 4 of the right-angled parallelogram.
Particles in which one or more, preferably 1 to 3 of one corner is non-equivalently missing. That is, [area of maximum missing part / area of minimum missing part) = particle in which a ₁ is 2 to ∞], (3) particle in which the four corners are equivalently missing (particle in which a ₁ is smaller than 2) ),
(4) 5 to 100% of the area of the missing portion, preferably 20 to
100% of the particles are (111) planes, (5) Particles in which at least two opposite sides of the four sides constituting the principal plane are convex curves outward, (6) of the right-angled parallelogram Particles in which one or more, preferably 1 to 3 of the four corners are missing in a right parallelogram shape. 2. Nucleation The nuclei of the (100) tabular grains are produced by the following method.
(1) In a low protective colloidal solution, a silver salt solution and a halogen salt solution (hereinafter referred to as "X ^- salt solution") are added to form nuclei. It is thought that crystal defects are formed by Coagulation. (2) Plate nucleation method by lattice constant mismatch. For example, a) a nucleus having at least one halogen composition gap surface, preferably 1 to 4, more preferably 1 to 3 is formed. Specifically, in (AgX ₁ | AgX ₂ ), X
The halogen compositions of ₁ and X ₂ differ in Cl ⁻ content, Br ⁻ content, or I ⁻ content by 10 to 100 mol%, preferably 30 to 100 mol%, and more preferably 60 to 100 mol%. Where (AgX ₁ | AgX ₂ ) is AgX
After forming _one nucleus, it refers to an embodiment in which an AgX ₂ layer is laminated on the surface of the nucleus. More specifically, X added during nucleation
^- refers to the halogen composition of the salt solution can be varied discontinuously according to the provisions at the gap surface. The gap is Ag
The X ₁ nucleus, X ₂ ^- salt solution added, halogen conversio
It can also be formed by giving n.

A flat plate nucleus having two gap surfaces is (Ag
X ₁ | AgX ₂ | AgX ₃ ). In addition, b) sulfur, selenium, tellurium between adjacent phases of the gap, in order to promote defect formation due to the lattice misfit,
Metal ions other than SCN ⁻ , SeCN ⁻ , TeCN ⁻ , CN ⁻ , and Ag ⁺ , and complexes of the metal ions (as the ligand, X ⁻ ligand, CN ⁻ ligand, isocyano,
Nitrosyl, thionitrosyl, amine, and hydroxyl) can be used, and the content difference of at least one of them is preferably 0.1 to 100 mol%, more preferably 1 to 100 mol%, and further preferably 10 to 10. A mode in which the difference is 100 mol% can be mentioned. As a typical example of a metal ion other than Ag ⁺ , a metal ion of Group 8 of the periodic table,
Cu, Zn, Cd, In, Sn, Au, Hg, Pb, C
Examples thereof include metal ions of r and Mn.

C) In addition, there can be mentioned a mode in which the defect is formed only by the impurity ion content gap. See Research Disclosure for specific compound examples of these impurity ions and details of the method for doping the AgX phase.
, 307, Item 307105, November, 198
9 years, U.S. Pat. Nos. 5,166,045, 4,933,272, 5,164,292, 5,132,203 and 4,269,992.
7, ibid 4847191, ibid 4933272, ibid 4981
781, the same 5024931, JP-A-4-305644,
Id. 4-321024, Id. 1-183647, Id. 2-20
The description of 853, 1-285941, and 3-118536 can be referred to.

In the present invention, the nucleation method of the above 2), preferably 2) a) can be preferably used, and the halogen conversion method can be more preferably used. The tabular grains are formed because there are defects that promote growth in the edge direction of the tabular grains. The defect is referred to as a screw dislocation defect in the present invention. When a large number of the defects are formed in one particle, growth is promoted in the three-dimensional direction, and the resulting particle becomes thick. When the defect formation probability is gradually increased from zero, tabular grains having an edge ratio of 1 to 2 are formed first. Therefore, the grains have a [110] direction or −25 °
It is considered to have one screw dislocation defect having a growth promoting vector in the direction of + 25 °. If the probability is further increased, the number of tabular grains produced increases, and if it is further increased, the mixing ratio of grains having a low aspect ratio increases. It is considered that this is because two or more defects are introduced per grain and have a growth acceleration vector in the thickness direction. Therefore, the probability may be increased within a range in which the mixing ratio of thick particles is allowed.

In addition to the method of forming the gap with a composition of (AgX ₁ | AgX ₂ ), (AgX ₁ | AgX ₁₂ | Ag
X ₂ ) may be formed by forming nuclei. In this case Ag
X ₁₂ is an intermediate layer having a halogen composition between Ag ₁ X ₁ and AgX ₂ . When the difference in halogen composition between AgX ₁ and AgX ₂ is increased, the number of tabular grain nuclei increases, but the ratio of the number of thick grain nuclei also increases. Inclusion of the intermediate layer increases the number of tabular grain nuclei produced, but has an effect of suppressing the production ratio of thick grain nuclei. In this case, the halogen composition gap amount of (AgX ₁ | AgX ₁₂ ) and (AgX ₁₂ | AgX ₂ ) is preferably 10 to 90%, and more preferably 30 to 70% of the gap amount of (AgX ₁ | AgX ₂ ). The number of the intermediate layers is 1 to 4, preferably 1. The intermediate layer can be provided for one or more of the gap surfaces even in the embodiment having two or more gap surfaces.

3. Aging Among the nuclei formed by nucleation, the number of non-tabular grain nuclei in the aging process is preferably 30 to 100%, more preferably 6%.
The projected area ratio of tabular grains is increased by eliminating 0 to 100%. Specifically, the AgX solubility of the reaction solution is increased to 1.1 times or more, preferably 1.5 to 30 times, and aging is performed. The following method can be mentioned as a method for increasing the solubility.
(1) Raise the temperature by 5 ° C or higher, preferably 10-60 ° C. (2) Add X ^- salt or silver salt. (3) Add AgX solvent. (4) A combination method of two or more of the above (1) to (3).
The (Cl ⁻ concentration / X ⁻ concentration) in the reaction solution is 0.9 to 1.
In the case of 0, 30% or more of the nuclei were first eliminated by the temperature increase, and then Cl ⁻ salt was added to increase the AgX solubility to 1.1 times or more, preferably 1.3 to 10 times, and the remaining 80 of the nucleus
It is more preferable to eliminate 100%, preferably 97 to 100%. After disappearance, the excess Cl ^- concentration is AgNO
It is possible to reduce the amount by adding the _3rd solution, or desalting by a conventionally known emulsion desalting method. AgNO ₃
The addition rate of the liquid can be selected as an optimum addition rate, and it is preferable to add at a rate at which no new nuclei are generated.

The nucleus forming the halogen composition gap surface is
When ripening and erasing non-tabular grain nuclei, grow at that time
Different halogen ions accumulate on the tabular grains. This time,
The tabular grains further incorporate defects such as screw dislocations,
Growth-promoting defect having a growth vector component perpendicular to the plane
The pit is incorporated. Therefore, the tabular grains will grow further as they grow.
Get thicker. To prevent this, different halogen ions
May be diluted with host halogen ions. Specific examples
When you get (inner core | outer core) becomes (AgX₁| AgX ₂) Nuclear
In the case, different ions X released during aging₂To dilute
And Ag⁺And X ₁ ^-A method of aging while adding
The structure is (AgX₁| AgX₂| AgX₁) And how
X with a particle diameter of 0.01 to 0.15 μm₁High composition ratio
A method of adding fine particles and a combination method of two or more thereof are mentioned.
Can be The dilution eliminates the non-tabular grain nuclei.
The number of screw dislocation defects newly formed when
The number of existing defects is preferably 0 to 0.9, and is preferably 0 to 0.2.
More preferable.

A-2. (111) Tabular grains 1. Grain Structure (111) When classified by the shape of the main plane of the tabular grain, the following two can be mentioned. (1) Hexagonal tabular grains whose main plane has a substantially hexagonal peripheral shape. Here, "substantially" means that the maximum adjacent side ratio [(longest side length / shortest side length) in one hexagon] is 1 to 2, preferably 1 to 1.
5, more preferably 1 to 1.2. (2)
Triangular tabular grains whose main plane has a substantially triangular peripheral shape. Here, “substantially” refers to a mode in which the ratio of adjacent sides is greater than 2. (3) A mode in which the corners of the particles of (1) and (2) above are rounded. The ratio (b ₁ ) of the straight line portion of the peripheral side is 0 to 0.5
And tabular grains of 0.5 <b ₁ ≦ 1.0. The b ₁ value refers to the ratio of the length of the straight line portion of the side to the length between intersections formed by extending the straight line portion of the surrounding side. (4) In the particles of (1) to (3), [area of {111} face of edge face / total area of edge face] is 0 to 1.0.
And a particle having [area of {100} face of edge face / total area of edge face] of 0 to 1.0. [{11 of the edge surface
Area of 1} / area of {100} face of edge surface] is 0.0
1-100 particles.

In the embodiment of the hexagonal tabular grain and the triangular tabular grain having the above six sides, the length (longest side length / shortest side length) = b ₂ of every other three sides is 1 to 1. 3 is preferable, 1-1.2 is more preferable, 1-1.1 is the most preferable. It is preferable that the total projected area of the grains accounts for 80% or more, preferably 90% or more, more preferably 97 to 100% of the total projected area of all AgX grains. The number of twin planes parallel to the main plane is 2 to 4, preferably 2 to 3, and more preferably 2. Two grains are usually the hexagonal tabular grains and three grains are the triangular tabular grains, but there is an embodiment in which two grains are the triangular tabular grains.
Particularly, it appears when thin tabular grains of 0.1 μm or less are grown under a low supersaturation degree. Although there are concave and convex corners on the edge surface, the concave corner grows faster due to the large number of atomic bond steps. Since thin tabular grains have a small (thickness / twin plane spacing), they are often (area of concave corner portion ≠ area of convex corner portion).

It is considered that when the grains are grown at low supersaturation, the side of (area of concave corner surface> area of convex corner surface) grows faster. It is considered that in the grain having three parallel twin planes, the growth rate of the edge portion is (edge portion having two recess angles> edge portion having one recess angle). This is because the edge portion having two recessed corner portions has a larger number of (growth active points / unit area) and a relationship of (recessed corner area> convex angle area) holds. (Thickness of tabular grains / distance between twin planes) or (thickness of tabular grains / distance between outermost twin planes) is 1.1 or more, preferably 1.5 to 100, more preferably 2 to 50. Is. The outermost twin plane refers to the twin plane closest to the principal plane. In the present invention, the hexagonal tabular grains or grains having rounded corners (0.5 <b ₁ <1.0)
Is preferable, the ratio of adjacent sides is more preferably 1 to 1.5,
1-1.2 is more preferable. The grains are hereinafter referred to as "regular hexagonal tabular grains".

2. Nucleation The temperature during nucleation is preferably 60 ° C or lower, 10 to 50 ° C.
Is more preferable. The dispersion medium concentration is preferably 0.01 to 5% by weight.
More preferably, 0.01 to 1% by weight is more preferable, and 0.03
˜0.6 wt% is more preferred. X^-Salt concentration is 10^-0.8
-10^-3Mol / l is preferred, 10^-1.2-10^-2.7Mo
Le / liter is more preferable, and 10^-1.6-10^-2.7Mol / li
Torr is more preferred. Ag to be added⁺Liquid and / or X
^-It is preferable that the liquid contains a dispersion medium, and the concentration is 0.01.
~ 1 wt% is preferred, 0.03-0.6 wt% is more
preferable. The molecular weight of the dispersion medium is preferably 3000 to 200,000.
More preferably 3000 to 100,000. PH of reaction solution
Is preferably 1 to 11, and more preferably 2 to 6. Dispersion medium
Is preferably gelatin, more preferably alkali-treated gelatin.
The modified gelatin described below is more preferable. Next ripening
Ripening in the process can be performed more quickly, and the tabular grain ratio
In order to further increase the rate, it was
It is preferable to form a nucleus. That is, low X ^-Concentration and low temperature are good
Good. X^-The decrease in twin plane formation probability due to the decrease in concentration
This can be compensated by reducing the concentration of the dispersion medium. Also,
Generally, the lower the pH, the lower the solubility of AgX in the dispersion medium.
It is preferable because 30% or more of the amount of silver salt added during nucleation
Above, preferably 60 to 100%, more preferably 80 to
100% is X^-It is preferable to add it simultaneously with the salt solution.

3. Aging Among the nuclei formed by nucleation, the number of non-tabular grain nuclei in the aging process is preferably 75 to 100%, more preferably 9%.
The projected area ratio of tabular grains is increased by eliminating 0 to 100%, more preferably 100%. Specifically, the solubility of the reaction solution is increased 1.1 times or more, preferably 1.5 to 30 times, and aging is performed. As the method for increasing the solubility, the above-mentioned A-
The method described in item 3 of 1 can be mentioned. The lower the concentration of the dispersion medium during the aging and the lower the pH, the faster the aging. It is considered that this is because the adsorption force of the dispersion medium to the AgX grains is weakened, the growth alienation factor of the tabular grains is removed, and the dissolution of the non-tabular grains is promoted. Regarding the concentration of the dispersion medium at the time of aging, the molecular weight of the dispersion medium, the pH of the reaction solution, and the type of the dispersion medium, the description in the above item 2 can be referred to. The X ^- salt concentration is preferably 10 ^-0.8 to 10 ^-2.5 mol / liter, more preferably 10 ^-1.2 to 10 ^-2 mol / liter.

B. Growth conditions of tabular grains In the present invention, the dispersion medium in the dispersion medium solution in the growth process is
100% by weight, preferably 60-100% by weight, more preferably 80-96% by weight (chemically modified --NH ₂
Gelatin having a relationship between% of the number of bases and methionine content in the region of a ₁ , preferably a ₂ , and more preferably a ₃ in FIG. 1)
Is. The following method can be mentioned as a method for realizing the embodiment.

(1) Nucleation and ripening are carried out using a dispersion medium other than the modified gelatin (hereinafter referred to as "unmodified medium"), and 10 to 99.7% by weight of the dispersion medium is removed before growth. Then, the modified gelatin is newly added. (2) Nucleation is performed using an unmodified medium, and after the nucleation, 10 to 99.
A method of removing 5% by weight and newly adding the modified gelatin. (3) A method of performing nucleation in a low concentration of an unmodified medium and adding the modified gelatin after the nucleation. (4) A method in which nucleation and ripening are carried out under a low concentration of an unmodified medium, and the modified gelatin is added after ripening. (5) A method of performing nucleation and ripening in the presence of the modified gelatin. The modified gelatin may be further added after nucleation or ripening. (6) A method in which nucleation is performed or ripening is performed in the presence of unmodified gelatin, and then the gelatin is modified with a modifying agent described below to increase the ratio of the modified gelatin. (7) Until after nucleation,
Or until ripening in the presence of unmodified gelatin,
Next, a method in which unmodified gelatin is added and homogenized and mixed, and then the gelatin is modified with a modifier described below to increase the ratio of the modified gelatin.

The following method can be mentioned as a method for removing the dispersion medium. 1) A method of centrifuging an AgX emulsion and removing a supernatant. 2) A method of removing by an ultrafiltration method using an ultrafiltration membrane. 3) A method of adding a coagulating sedimentation agent and washing with sedimentation water, or a method used in combination with a centrifugation method. The removal rate of the dispersion medium is preferably from 30 to 99.5% by weight, and from 60 to 99.
% Is more preferable. The above methods (1) to (4), (6) and (7) can be more preferably used. The low concentration of (3) and (4) is 0.01 to 1% by weight, preferably 0.03 to 0.6.
%, More preferably 0.03 to 0.3% by weight. The amount of modified gelatin added later is the amount necessary to achieve the embodiment of the present invention.

In order to grow the tabular grains without making them thick and without broadening the size distribution, it is necessary to precisely control the adsorptivity of the dispersion medium for the AgX grains. When H ₂ O ₂ was added to the gelatin aqueous solution to oxidize the gelatin, H ₂ O ₂
The number of methionine sulfoxide groups / the number of methionine groups = C _{1 of} gelatin increases with the addition amount of. As C ₁ increases, the adsorptivity of gelatin to AgX particles decreases. When various (111) tabular grains are grown in the aqueous solution using various gelatins having different C ₁ values, the obtained tabular grains become thinner as the C ₁ value increases, but at the same time, the size distribution becomes smaller. Spreads. This phenomenon can be understood as follows.

Due to the oxidation, the lysine group, the aspartic acid group and the glutamic acid group were not changed at all, and this change can be attributed to the change in the C ₁ value. That is, since the strong adsorption of the methionine group is eliminated, the growth rate of the edge surface of the tabular grain changes from the desorption rate of the methionine group to the reaction rate of the edge surface. Since the growth active site of the (111) tabular grain is the concave corner portion of the edge, the probability that a growth nucleus is formed on the concave corner portion of one tabular grain is proportional to the edge length around the tabular grain. . Since the edge length (2πd) is proportional to the diameter (d), the growth nucleus formation probability is proportional to d. When the growth nucleation process is growth-controlled, the growth rate is (large particles> small particles), and the size distribution broadens with growth.

However, 1 methionine was added to the oxidized gelatin.
The thin tabular grains are formed even when tabular grains are grown by adding only 0.001 to 1000 (μmol / g gelatin). Therefore, the methionine group in gelatin alone does not have a strong adsorptive power. The amino group of gelatin is phthalated with phthalic anhydride to prepare gelatin with various phthalation rates. Next, when the same seed crystal tabular grains are grown in the dispersion medium under the same conditions, the tabular grains produced become thinner as the phthalation rate increases, but the size distribution does not broaden. Therefore, in order to prepare thin tabular grains having a uniform size distribution, it is necessary to select the optimum combination of the methionine group content and the amino group content of gelatin. The selection of this optimum value was made for the first time by the present invention. 1-Phenyl-5-mercaptotetrazole strongly adsorbs to AgX particles, but the mercapto group alone or the tetrazole group alone does not exhibit such strong adsorption. The said phenomenon can be considered similarly to this. That is, the strong adsorption of gelatin on AgX particles is due to the presence of methionine groups and -N in the gelatin molecule.
It is considered that this is caused by the concerted effect of the H ₂ group. Also, the when grown oxide gelatin, tabular grains distorted hexagonal shape is formed, a ₁ in the region of Figure 1,
Preferably, when gelatin in the region a ₂ is used, regular hexagonal tabular grains are formed.

Another major factor controlling the adsorptive power of the dispersion medium for AgX particles is temperature. Even with the same dispersion medium, the lower the temperature, the lower the frequency of desorption of the adsorbing groups, and the more the particle growth becomes desorption-controlled growth. In this case, all the surfaces of the tabular grains are closer to uniform growth.
Therefore, the higher the temperature, the more the desorption limiting rate is removed, the edge selective growth property is enhanced, and tabular grains having a higher aspect ratio are obtained. When the same tabular grains are grown at various temperatures of 30 to 80 ° C. using various dispersion media, the aspect ratio change of the resulting tabular grains has a high methionine content and a free amino group content of Higher gelatin is bigger. In the embodiment of the present invention, the temperature change is small, and monodisperse tabular grains having a high aspect ratio in a wide temperature range can be obtained. Further, since the appropriate adsorption force to the AgX particles is maintained, the occurrence of fogging is suppressed, and particles having a high (sensitivity / fogging) ratio can be obtained. The growth temperature is preferably 30 ° C or higher, more preferably 40 to 90 ° C. The most preferable temperature can be selected and used. Another major factor controlling the adsorptive power of the dispersion medium for AgX particles is pH.
Dispersion medium solutions of various pHs are prepared using oxidized gelatin having a methionine content of zero. When the same (111) tabular seed crystal is put into each solution and grown, the mixing ratio of thick tabular grains increases as the pH rises. pH 8 or higher,
Especially, it becomes remarkable at pH 9 or higher. At this time, since methionine sulfoxide does not change, it is shown that methionine is not the only cause of thick plate particles. On the other hand, when the modified gelatin of the present invention is used, the pH dependence is small, and even at pH 9 to 10, thick plate particles are not mixed.
That is, when the growth pH is 6 to 11, preferably 6 to 10, the advantage becomes greater. On the other hand, in the case of (100) tabular grains, the thinner the tabular grains are, the higher the pH of aging and growth conditions is.

The growth of these tabular grains is preferably carried out by selecting the most preferable degree of supersaturation according to the purpose.
When the critical supersaturation degree is 100 and the supersaturation degree when no solute is added is 0, 5 to 90 is preferable, and 10 to 80 is more preferable. Here, the critical degree of supersaturation refers to the degree of supersaturation in a state where new nuclei are generated when AgNO ₃ aqueous solution and X ^- salt aqueous solution are simultaneously mixed and added, and when added at a higher addition rate. If the degree of supersaturation is increased, the resulting tabular grains will be more monodispersed, but will also grow in the thickness direction and have a low aspect ratio. Lowering the degree of supersaturation leads to a higher aspect ratio, but a wider size distribution. The concentration of the dispersion medium during growth is preferably 0.1 to 7% by weight, and 0.3 to 3% by weight.
Is more preferable. The molecular weight is 3000 to 200,000, preferably 6000 to 120,000. The pH of the solution is preferably a pH above the isoelectric point of the modified gelatin, (isoelectric point pH + 0.
2) to pH 11 is more preferable, and (isoelectric point pH + 0.
4) to pH 10 are more preferable. When tabular grains are grown under the same conditions, the lower the pH, the lower the gelatin concentration, the lower the molecular weight, the higher the aspect ratio of the tabular grains produced. The most preferable combination can be selected and used according to the purpose.

The concentration of X ^{− in} the reaction solution during ripening and growth of the (111) tabular grains is preferably in the octahedral grain forming region. Here, the octahedral grain formation region means that, when Ag ⁺ and X ⁻ are simultaneously mixed and added while maintaining the X ⁻ concentration condition to form AgX grains, 70 to 100%, preferably 90 to 100% of the grain surface is formed. Indicates the concentration range in which particles on the {111} plane are generated. Usually, the X ⁻ concentration is preferably 10 ^−0.5 to 10 ^−2.5 mol / liter, more preferably 10 ⁻¹ to 10 ⁻² mol / liter. The characteristics are (111) tabular grains and (10
0) Also seen in tabular grains. Therefore, (10
0) It can also be preferably used for tabular grains.
The X ^- concentration in the reaction solution during nucleation, ripening and growth of (100) tabular grains is preferably in the cubic grain forming region. Here, the cubic particle generation region means that when Ag ⁺ and X ⁻ are simultaneously mixed and added while maintaining the X ⁻ concentration condition to form AgX particles, 70 to 100%, preferably 90 to 1% of the particle surface is formed.
00% refers to the concentration range in which particles of {100} plane are generated. Usually, the X ⁻ and Ag ⁺ concentrations are 10 ^−1.5 mol /
It is preferably liter or less, more preferably 10 ^-2 mol / liter or less. Other details of the tabular grains are described in the above-mentioned "Prior Art" and JP-A-3-288143, JP-A-3-212639 and 3-1.
No. 16133, No. 2-301742, No. 2-34,
6-59360, Japanese Patent Application No. 6-47991, 5-
248218, 5-264059, 5-962
Reference can be made to the description of No. 50, which will be described later.

C. Modified gelatin As the —NH ₂ group in gelatin, in addition to the amino group, lysine group, hydroxylysine group, histidine group, amino group of arginine group at the terminal group of the gelatin molecule, if the arginine group is converted to the ornithine group, The amino group can be mentioned. Furthermore, impurity groups such as adenine and guanine groups can be mentioned. The chemical modification of —NH ₂ group means adding a reaction reagent to gelatin and reacting with the amino group to form a covalent bond or deamination. That is, secondary amino group and primary amino group _{(-NH 2) (-NH -)} , refers to a change in the tertiary amino group or a deaminated body.

Specifically, for example, acid anhydrides (maleic anhydride, o-phthalic anhydride, succinic anhydride, isatoic
anhydride, benzoic anhydride, etc., acid halide (R
_{-COX, R-SO 2 X,} R-O-COX, R-O-C
OX, Rh-COCl, etc.), compounds having an aldehyde group (R-CHO, etc.), compounds having an epoxy group, deamino bases (HNO ₂ , deaminase, etc.), active ester compounds (sulfonic acid ester, p-nitrophenyl) Acetate, isopropenyl acetate, methyl o-chlorobenzoate, p-nitrophenyl benzoate, etc.), isocyanate compounds (Aryl isocyanate, etc.), active halogen compounds such as [Aryl halide (benzyl bromide, b
iphenyl-halomethanes, benzoyl halomethanes, phenyl
benzoylhalo-methane, 1-Fluoro-2,4-dinitro-benzen
e), β-ketohalide, α-haloaliphatic acid, β-hal
onitrile, (s-triazine, pyrimidine, pyridazine, pyr
azine, pyridazone, quinoxaline, quinazoline, phtha
lazine, benzoxazole, benzothiazole, benzoimidazol
e) chloro derivative], carbamoylating agent (cyanate, nit
rourea etc.), compounds having an acrylic double bond group (maleimide, acrylamine, acrylamide, acrylonitril)
e, methylmethaacrylate, vinyl sulphone, vinylsulph
onate ester, sulphonamide, styrene and vinylpyridi
ne, allylamine, butadiene, isoprene, chloroprene
Etc.), sultones (butane sultone, propane sultone),
Guanidine agent (o-methylisourea, etc.), carboxylazide
It can be achieved by adding such substances and reacting.

In this case, --OH groups of gelatin and --COO
A reagent that reacts mainly with the -NH ₂ group of gelatin is more preferable than a reagent that also reacts with an H group and forms a covalent bond. Mainly 60% or more, preferably 80-100
%, More preferably 95 to 100%. Furthermore, it is more preferable that the reaction product does not substantially contain (group in which oxygen of ether group or ketone group replaces chalcogen atom, for example, —S—, thione group). Here, "not substantially containing" means preferably 10% or less, and more preferably 0 to 3% of the number of chemically modified groups. Therefore, of the above,
Acid anhydrides, sultones, compounds having an active double bond group, carbamoylating agents, active halogen compounds, isocyanate compounds, active ester compounds, compounds having an aldehyde, and deamination bases are more preferred. It is more preferable that the chemical modification does not substantially allow crosslinking between gelatin molecules. The term "substantially impossible" means preferably 10% or less, more preferably 0 to 3% of the chemically modified group.

Other details of the chemical modifier and the chemical modification method of gelatin are described in the following references, JP-A-4-4-2.
26449, JP-A-50-3329, US Pat. No. 25
25753, 2614928, and 2614929.
No. 275639, No. 2594293, No. 31
No. 32945, edited by Abiko Yoshihiro, glue and gelatin, No. II
Chapter, Japanese Niwa-Gelatin Industry Association (1987), Wa
Reference can be made to the description of rd et al., The Science and Technology of Gelatin, Chapter 7, Academic Press (1977). % Of chemical modification of --NH ₂ group of the modified gelatin
Can be determined as follows. Prepare gelatin which has not been modified and gelatin which has been modified,
The numbers of —NH ₂ groups of both are determined as e ₁ and e ₂ . The chemical modification percentage can be calculated from 100 × (e ₁ −e ₂ ) / e ₁ . The e ₁ and e ₂ can be determined by infrared absorption intensity based on —NH ₂ group, NMR signal intensity of the proton, and a method utilizing color reaction and fluorescence reaction. Reference can be made to the description in Handbook, Organic Edition-2, Maruzen (1991). In addition, changes in the titration curve of gelatin and quantitative methods such as the formol titration method can be mentioned. For details, see The Science and Technology of Gelatin, No. 15
You can refer to the description in Chapter, Academic Press (1977).

In addition, glutaraldehyde and Britton-Ro
binson A method in which a mixture of high pH buffer solution is added to a gelatin solution of a specified concentration to cause color development, and the spectral absorption intensity near 450 nm is measured and colorimetrically determined [Photogra
phic Gelatin II, p. 297-315, Academic Press
(1976 can be referred to). The methionine content of the gelatin can be determined by completely decomposing gelatin into amino acids by an alkaline hydrolysis method, analyzing the amino acids with an amino acid analyzer, and determining the amount of methionine relative to the amount of glycine. For details, see Japanese Patent Application No. 6-
The description of 102485 can be referred to. The methionine content of the gelatin can be adjusted by adding an oxidizing agent to the gelatin aqueous solution and oxidizing the -S- group of methionine to one or more of sulfoxide, sulfonate, and sulfone. It is preferably oxidized to sulfoxide. That is, in the present invention, the oxidized form of methionine is not regarded as methionine. The level of the oxidation can be adjusted mainly by the kind of the oxidizing agent to be added and the addition amount thereof.
The temperature of the aqueous solution is preferably 10 to 70 ° C. and 25 to 50 ° C.
C is more preferred. 2-9 are preferable and, as for pH, 3-7 are more preferable. Usually, an oxidizing agent is added to a gelatin aqueous solution whose temperature and pH are adjusted to be constant, and the mixture is homogeneously mixed. Next, the container is capped, allowed to stand at a constant temperature, and allowed to stand for preferably 15 minutes to 3 days, more preferably 1 to 24 hours.
Regarding the oxidizing agent, the description in Japanese Patent Application No. 6-102485 can be referred to. Usually, H ₂ O ₂ can be preferably used.

Due to the oxidation, the extinction coefficient of gelatin (20
(0 to 500 nm wavelength range) decreases. Therefore, if reagents having various oxidation levels are prepared and the relationship between the extinction coefficient and the methionine content is determined, thereafter, the methionine content of the gelatin can be easily determined by measuring the extinction coefficient. The amino acid composition of standard gelatin is The Theory
of The Photographic Process, Chapter 2, Macmilan (1
977), and methionine is 8 in one molecule.
Molecule is included. When the molecular weight of gelatin is 96,000, the methionine content is 83 μmol / g, and it can be considered that the methionine content of conventional gelatin is about 80 μmol / g. The methionine content is preferably 75 μmol / g or less, more preferably 10 to 60 μmol / g, 32.5
˜50 μmol / g is more preferred.

D. PAO polymer A polyalkylene oxide polymer (hereinafter referred to as “PAO polymer”) is added before nucleation to 5 minutes before the end of growth, preferably after nucleation to just before the start of growth. Things are preferred. It can be more preferably added to the formation of tabular grains, and further to the formation of (111) tabular grains having a Br ⁻ content of 50 to 100 mol%. Details of the PAO polymer are described in European Patent 0514742A1, Japanese Patent Application Nos. 5-118418, 5-191814, and 5-26.
The compound described in 3128 is preferable, and especially Japanese Patent Application No. 5-1
91814 and the aspect of the said 5-263128 can be used preferably. The molecular weight of the compound is 500 to 10 ⁶
Is preferred, and 10 ³ to 10 ⁵ is more preferred. The addition amount is preferably 0.001 to 20 g / liter, and 0.003 to
More preferably 10 g / liter. PH during grain growth is 5
11 is preferable, and 5-9.5 is more preferable.

The order of the strength of adsorption of the organic ether compound to the AgX particles is generally -O-<-S-<-.
Se-<-Te-. Since the adsorption power of the oxygen ether group to the AgX particles is weaker than that of the thioether group, the growth of the AgX particles is not strongly suppressed. Also,
Since the adsorption on the AgX particles is based on the Van der Waalsca, the AgX particles are selectively adsorbed on the {100} surface rather than the {111} surface. This is because the {100} plane has Ag ⁺ and X ⁻ and has a larger induced dipole moment than the {111} plane. In the (111) tabular grains, the {100} plane is likely to appear because it is the edge plane.
O is adsorbed to the edge surface rather than the main plane with an appropriate adsorption force.
Then, the growth rate control of the edge surface is changed to the desorption rate control of PAO. If the number of adsorbed molecules of PAO per unit area is equal, both large particles and small particles have the same growth rate in each unit area. Therefore, the edge surface of both the large particles and the small particles grows at a constant speed, and the coefficient of variation of the diameter distribution decreases with the growth.

The crystal habit dependence of the adsorption of the PAO polymer can be determined by the following method. A monodisperse cubic grain emulsion and an octahedral grain emulsion having the same surface area are prepared, and a PAO compound is added to each of them to reach adsorption equilibrium, followed by centrifugation and analysis of the supernatant. For example, when the temperature is equal to or higher than the cloud point of the PAO, it can be obtained by comparing the spectral transmission intensities. In addition, a method of separating and analyzing the PAO component by a chromatography method (for example, gel filtration chromatography method) can be mentioned. Alternatively, the ionic conductivity of the cubic and octahedral particles may be measured by the dielectric loss method, and the amount of change in ionic conductivity due to the adsorption may be determined for comparison.

Adsorption of conventional gelatin to AgX grains usually occurs more strongly on the {100} plane than on the {111} plane. This is because the adsorption is mainly based on the interaction with Ag ⁺ on the particle surface. In this case, the PAO polymer {10
Adsorption to the 0} plane is excluded. However, in the case of the modified gelatin, since it is weakly adsorbed on the AgX particles, it is possible to selectively adsorb on the {100} plane of the PAO polymer, and the preferable growth characteristics of the above embodiment can be obtained. Since the PAO polymer increases the ionic conductivity of AgBr particles by the adsorption, {1
It is considered that the interaction of the 00} plane with Br ⁻ is large.
The interaction between the PAO polymer and X ⁻ in the aqueous solution can be determined by the following method. An X ^- selective electrode was placed in each of the aqueous solution containing PAO and the aqueous solution not containing PAO,
The relationship between the added amount of X ^- salt and the electrode potential (relative to the standard electrode) may be obtained and compared. X incorporated in PAO polymer
^- the power level change by an amount worth is small.

The first embodiment of the PAO polymer is HPAO and is represented by the above general formula (1) -a) or (1) -b). HPEOU represents a new aqueous polyalkylene oxide unit, and more specifically, it is represented by the formula (1) -c). LPAOU represents a new oily polyalkylene oxide unit, and is more specifically represented by the formula (1) -d). The molecular weight of HPEOU is 96.1 of the molecular weight of the whole molecule.
To 100%, preferably 97 to 100% (HP1) and 4 to 96% (HP2). In the formula (1), R ⁰ is H or a hydrocarbon having at least one polar group and having 1 to 10 carbon atoms, and preferably H. R is 3 or more carbon atoms, an alkylene group having 10 or less, -CH (CH ₃₎ Examples CH ₂ -
, -CH ₂ CH (CH ₃ )-, -CH ₂ CH ₂ CH _2- , -CH ₂ CH (OH) CH ₂ ,-
(CH ₂ ) ₄ -,-(CH ₂ ) _5- , -CH ₂ CH (C ₆ H ₅ )-can be mentioned, and -CH (CH ₃ ) CH _2- , -CH ₂ CH (CH ₃ ). -Is particularly preferable.
n and m represent the average number of repeating units and are values of 4 or more that satisfy the above-mentioned molecular weight regulation.

However, the selectivity of the ring-opening position of the cyclic ether at the time of polymerization is not sufficient, so that in the above formula (1) -d), for example,-[CH ₂ CH (CH ₃ ) O]-and-[CH ( CH ₃₎ CH ₂ O] - it is sometimes mixed. The second embodiment of the PAO polymer is PEOD, which is represented by the general formula (a) to (f) of the formula (2). Here, LPU refers to a lipophilic group other than a HO-HPEOU- group and a HO-LPAOU- group, and a substituted or unsubstituted alkyl group, alkenyl group, aryl group, heterocyclic group, alkoxy group, aryloxy group, acyl group,
It refers to an acylamino group, an alkylthio group, an arylthio group, an alkoxycarbonyl group, an aryloxycarbonyl group, and an alicyclic group, and a compound containing no divalent sulfur, selenium, or tellurium is more preferable. Specific examples of the HPAO compound are shown in formulas (10) a) to c), and specific examples of the PEOD are shown in formula (11) a) to b).

[0046]

[Chemical 7]

In the formula, a and b are integers of 1 to 25, and n
_{1 to} n ₃ are values of _{1 to} 10,000 which satisfy the above-mentioned molecular weight specifications of HPAO and PEOD. For other details of the polymers of the first and second aspects, see Japanese Patent Application No. 5-118.
The description of No. 418 can be referred to. The third mode of the PAO polymer is a mode in which at least one polymer having a repeating unit of the monomer represented by the general formula (3) is contained. In the fourth aspect, the polymer is at least two kinds of the monomer represented by the general formula (3) and the monomer represented by the general formula (4): 1: 100 to 100: 1, preferably 5 to 100 to 100: In this embodiment, the copolymer is a 5 molar ratio.

In the equations (3) and (4), R ¹ , R
⁴ may be the same or different, H, a lower alkyl group having 1 to 4 carbon atoms (methyl, ethyl, n-propyl, n-
Butyl), with H and methyl groups being particularly preferred. R ² ,
R ^{5 s} may be the same or different and each represents a monovalent substituent, preferably H, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or an acyl group, particularly H, a methyl group or an ethyl group. , Phenyl group and acetyl group are preferred.
n and m represent the average number of repeating units, n is 4 to 600,
Preferably 4-200, m is 4-600, preferably 4
~ 200. L and L'represent a divalent linking group.

Specific examples of the monomer represented by the general formula (3) are as follows. (3) -a) -1) CH ₂ ＝ C (CH ₃ ) -COO- CH ₂ CH (CH ₃ ) O _n -H n = 6 (3) -a) -2) 〃 n = 9 (3) -a) -3) 〃 n = 12 (3) -a) -4) 〃 n = 20 (3) -a) -5) 〃 n = 40

Specific examples of the monomer represented by the general formula (4) are as follows. (4) -a) -1) CH ₂ = C (CH ₃ ) -COO- (CH ₂ CH ₂ O) _n -CH ₃ n = 4 (4) -a) -2) 〃 n = 9 (4) -a) -3) 〃 n = 15 (4) -a) -4) 〃 n = 23 (4) -a) -5) 〃 n = 50

The proportion of the monomer represented by formula (3) in the polymer is 1 to 90% by weight, preferably 85% by weight, more preferably 5 to 70% by weight. The proportion of the monomer of the formula (4) in the copolymer of the monomers of the formulas (3) and (4) is 1 to 90% by weight, preferably 2 to 70% by weight, more preferably 3 to 50% by weight. is there. The monomer of the formula (3) and / or the monomer of the formula (4) and another monomer can be copolymerized and used. Specific examples of the other monomer include acrylic acid esters, methacrylic acid esters, acrylamides, methacrylamides, vinyl esters, vinyl ketones, allyl compounds, olefins, vinyl ethers, N-vinyl amides, vinyl heterocyclic rings. Compounds, maleic acid esters, itaconic acid esters, fumaric acid esters, and crotonic acid esters. The copolymerization amount is 0 to 99% by weight, preferably 0 to 90% by weight.

Specific examples of the copolymer of the monomer of the formula (3), the monomer of the formula (4) and the other monomer are (12) -1) to (12)
This is shown in the equation (5). In the parentheses, the weight percentage of each monomer in the polymer is shown. (12) -1) (3) -a) -3) / (4) -a) -4) / acrylamide copolymer (5/5/90) (12) -2) 〃 (10/10/80 ) (12) -3) 〃 (25/25/50) (12) -4) 〃 (35/35/30) (12) -5) (3) -a) -3) / (4) -a ) -4) Copolymer (50/50)

Others of the PAO polymers of the third and fourth aspects
For details, refer to the description in Japanese Patent Application No. 5-191814.
Can be A fifth aspect of the PAO polymer is
The repeating unit represented by the general formula (5) is 1 in the dispersion medium solution.
At least one polymer contained in an amount of not less than wt%;
Contains 1 wt% or more of the repeating unit represented by the general formula (6)
It is an embodiment in which each polymer is contained at the above concentration. The
In the formula, R represents an alkylene group having 3 to 10 carbon atoms.
As a specific example, -CH (CH₃) CH₂-, -CH₂CH (CH₃)-,-CH₂CH
₂CH₂-, -CH₂CH (OH) CH₂,-(CH₂)_Four-,-(CH₂) _Five-, -CH₂CH
(C₆H_Five)-Can be mentioned, and -CH (CH₃) CH₂-, -CH₂CH (C
H₃)-Is particularly preferred. n and m represent the average number of repeating units
However, it is a value of 4 or more that satisfies the above-mentioned molecular weight regulation.

The sixth aspect of the PAO polymer is the same as the fifth aspect.
On the other hand, the following limitation is added. It is expressed by equation (5)
Is a vinyl monomer which is a monomer represented by the formula (7) -a).
Polymer or polyurethane represented by the formula (7) -b)
At least one polymer selected from the group consisting of
Is a vinyl monomer containing a monomer represented by the formula (7) -c).
Polymer, a polyurethane represented by the formula (7) -d), and
And substituted or unsubstituted polyethylene glycol
Which is at least one polymer described above. In the formula, n,
m is 4 or more, preferably 4 to 600, more preferably 4
It can take a value of ~ 80. R¹, R^FourIs H or 1 carbon
4 represents a lower alkyl group. R ², R^FiveIs H or charcoal
It represents a monovalent substituent having a prime number of 1 to 20. L and L'are divalent
Represents a linking group. R¹¹, R¹²Represents a divalent linking group, carbon
C1-C20 alkylene group, C6-C20 phenyle
Or an aralkylene group having 7 to 20 carbon atoms.
x, y, z, x ', y', z'is the weight percentage of each component.
Where x and x'are 1 to 70, preferably 5 to 40, y,
y ′ is 1 to 70, preferably 3 to 50, and z and z ′ are 20.
Represents 70 to 70, preferably 30 to 60. Where x + y +
z = 100 and x '+ y' + z '= 100. R is charcoal
Represents an alkylene group having a prime number of 3 to 10 and is the same as above.
It The repeating unit represented by — (R—O) — is a polymer.
Among them, only one kind may be used, or two or more kinds
Good. In addition,-(RO)-or-(CH₂CH₂O)-
Two or more kinds with different average number of return units (molecular weight)
It may be used.

The polymer represented by the formula (5) can be preferably used as long as it contains the repeating unit represented by the formula (5). A polymer or a polyurethane having a repeating unit represented by the general formula (7) -b) can be more preferably used, and the vinyl polymer can be more preferably used. (7) −
a) Specific examples of the monomer represented by the formula (7) -a) -1) to (7)-
It is shown in the formula a) -5).

[0056]

Embedded image

In the vinyl polymer, the proportion of the monomer unit represented by (7) -a) is 1 to 90% by weight,
It is preferably 5 to 70% by weight. Specific examples of the vinyl polymer of the monomer of the formula (7) -a) are (8) -a) -1) to (8) -a)-
In the formula (3), a specific example of the polyurethane of the formula (7) -b) is (8)
-b) -1) to (8) -b) -2). The percentage in weight is shown in parentheses. (8) -a) -1): (7) -a) -3) / acrylamide copolymer (25/7
5) (8) -a) -2): (7) -a) -3) / acrylic acid / acrylamide copolymer (50/30/20) (8) -a) -3): (7)- a) -3) / acrylic acid copolymer (70/30) (8) -b) -1): isophorone diisocyanate / 2,2-bis (hydroxymethyl) sodium propionate / polypropylene oxide (molecular weight 400) / polypropylene Oxide (molecular weight 1000) (43.1 / 21.5 / 15.7 / 19.7). (8) -b) -2): Toluene diisocyanate / 2,2-bis (hydroxymethyl) butanoic acid soda / polypropylene oxide (molecular weight 1000) (29.3 / 20.1 / 50.6). The polyurethane is basically synthesized by adding a diol compound and a diisocyanate compound.

The polymer represented by the formula (6) can be preferably used as long as it contains the repeating unit represented by the formula (6), but the monomer represented by the general formula (7) -c) alone is used. Polymers or copolymers, polyethylene glycols, substituted polyethylene glycols, polyurethanes represented by the formula (7) -d) can be preferably used, and the homopolymers can be more preferably used.

The monomer of the formula (7) -c) may be copolymerized with another ethylenically unsaturated monomer. In the copolymer, the proportion of the monomer of formula (7) -c) is 1 to 100.
%, Preferably 10 to 80% by weight. (7) −
Specific examples of the monomer represented by the formula c) are as follows. CH ₂ = CH (CH ₃ ) -COO- (CH ₂ CH ₂ O) _n -CH ₃ (7) -c) -1) n = 4 (7) -c) -2) n = 9 (7)- c) -3) n = 15 (7) -c) -4) n = 23 (7) -c) -5) n = 50 (6) Other than the polymer having the repeating unit represented by the formula, Examples thereof include polyethylene glycol, substituted polyethylene glycol having a substituent having 1 to 30 carbon atoms, and polyurethane. The proportion of polyethylene oxide in the polyurethane polymer represented by the formula (7) -d) is 1 to 70% by weight, preferably 5 to 40% by weight.

Next, specific examples of the polymer of the monomer represented by the formula (7) -c) are shown in the formula (8) -c), and examples of the polymer of the formula (7) -d) are (8) -d). Shown in the formula. (8) -c) -1 (7)-(c) -3 / acrylamide copolymer (10/90) (8) -c) -2 〃 (25/75) (8) -c) -3 〃 (50/50) (8) -c) -4 (7)-(c) -3 Homocopolymer (8) -d) -1 Toluene diisocyanate / 2,2-bis (hydroxymethyl) sodium butanoate / Polyethylene glycol (molecular weight 1000) (29.3 / 20.1 / 50.6) (8) -d) -2 4,4'-diphenylmethane diisocyanate / 2,2-bis (hydroxymethyl) sodium propionate / Polyethylene glycol (molecular weight 400) ( (45.3 / 11.3 / 43.4)

For the other details of the fifth and sixth aspects, the description in Japanese Patent Application No. 5-263128 can be referred to. In the present invention, HP1 of the first aspect and the second to sixth aspects can be preferably used, the second to sixth aspects can be more preferably used, and the third to sixth aspects can be more preferably used. Furthermore, the fifth and sixth aspects are most preferable.
For more details on the PAO polymer, see Davidsohn.
Et al, Synthetic Detergents, John Wiley & Sons, New Y
Ork (1987), edited by Tadanori Misawa, water-soluble polymer, Kagaku Kogyosha (1990), Hiroshi Horiguchi, New Surfactant, Sankyo Publishing (1975), Takehiko Fujimoto, Introduction of New Surfactants, Sanyo Kasei ( 1976), Chemical Society of Japan, Handbook of Chemistry, No. 4-
Reference can be made to Section 6, Maruzen (1984), Toshiyuki Yoshida, et al., Surfactant Handbook, Engineering Books, and the references described below. The optimum addition ratio of the polymer represented by the formula (5) and the polymer represented by the formula (6) changes depending on the halogen composition of AgX particles and the growth conditions (temperature, pH, pAg, etc.). However, in the case of the fifth and sixth aspects, if both polymers are prepared, the optimum conditions can be selected by changing the addition amount ratio. However, in the case of the fourth aspect, it is necessary to prepare a polymer in which the polymerization ratio of the monomer of the formula (3) and the monomer of the formula (4) is variously changed, and it is difficult to deal with it in detail. In addition, a large number of products will be produced in small quantities, resulting in higher costs. Therefore, in this respect, the fifth and sixth aspects are more preferable than the fourth aspect.

E. Ag ⁺ and X ^- in the supply method Ag ⁺ and X in the growth process ^- the method of feed, 1) a soluble silver salt was dissolved silver salt solution and a soluble halogen salt halide salt solution obtained by dissolving (hereinafter "X ^- A salt solution)), an ionic solution addition method, 2) a method of previously forming an AgX fine grain emulsion and supplying the fine grain emulsion, 3) a splash addition method, 4) a combination method of the both. it can. Examples of the soluble silver salt and the soluble halogen salt include salts having a solubility in water at room temperature of 1% by weight or more, preferably 10% by weight or more.
The description in Chapter 8, Maruzen (1993) can be referred to. Usually, AgNO ₃ and an alkali metal salt or ammonium salt of Cl ⁻ , Br ⁻ or I ⁻ can be preferably used. The particle diameter (diameter of a circle having an area equal to the projected area of the particle) of AgX fine particles is 0.15 μm.
The following is preferable, 0.01 to 0.1 μm is more preferable, and 0.02 to 0.06 μm is further preferable. The halogen composition may be AgCl, AgBr, AgI, or a mixed crystal of two or more thereof.

The size distribution has a coefficient of variation of preferably 0 to 0.4, more preferably 0 to 0.2, and further preferably 0 to 0.1. The fine particles preferably have substantially no twin or more twin planes, and more preferably have substantially no single twin grains. Furthermore, it is preferable that the compound does not substantially have a screw dislocation defect. Here, the number of “not substantially having” is preferably 3% or less, more preferably 1% or less, and further preferably 0 to 0.1%. The fine particles can be added continuously or intermittently.
The halogen composition of the fine particles to be supplied can be continuously changed or intermittently changed with respect to the supply time. The pH of the fine grain emulsion is 1 to 12, p
X can select the most preferable combination of 0.5-6.

When forming the fine particles, a dispersion medium that strongly adsorbs to the AgX particles enables the formation of the above-mentioned fine particles. On the other hand, when the fine particles are supplied to grow tabular grains, the bond between the dispersion medium and the AgX grains is preferably weak.
This is because it promotes dissolution of the fine grains and growth of tabular grains. Therefore, after the AgX fine particles are formed in a dispersion medium solution, the treatment is performed, and the complex forming ability with Ag ⁺ per unit weight of the dispersion medium under the same conditions is 10% or more, preferably 30 to 99%. Or more, more preferably 60
It is preferable to lower the amount by ˜95%, more preferably by 80 to 95%. Here, the treatment means adding an oxidizing agent such as H ₂ O ₂ to oxidize the dispersion medium and / or adding the modifying agent to chemically modify the amino group. For details of the treatment and other details of the method for adding fine particles, the description in Japanese Patent Application No. 6-102485 can be referred to.

Any conventionally known apparatus can be used as the apparatus for supplying Ag ⁺ and X ⁻ and the apparatus for forming particles during nucleation, ripening and growth. Addition holes are provided in the dispersion medium solution, and the number of addition holes (number of addition holes / 1 addition liquid) is 2 or more, preferably 4 to 10 ¹⁵ , and the addition holes are made of a rubber elastic film, A mode in which the holes are opened and the holes are closed when the addition is stopped can be preferably used. For details of the method of adding fine particles and the conventional apparatus, reference is made to the following documents, and JP-A-3-21339 and JP-A-183417,
4-34544, 4-193336, 4-330
427, 3-1555539, 3-200952, 3-246534, 4-283741, 4-184.
326-184330, 5-11377, 5-45
757, 5-61134, 5-337350, 6
-11779, U.S. Pat. No. 5,254,454, Japanese Patent Application No. 4-
240283, 4-302605, 5-25314.
You can refer to the description of.

F. Manufacturing process of internal latent C / S emulsion The manufacturing process of internal latent C / S emulsion is usually core particle formation → water.
Washing → Chemical sensitization of core surface → Attaching shell → Washing with water → Shell table
It is performed by surface chemical sensitization → spectral sensitization. In the present invention,
Chemical sensitization and spectral sensitization depending on other purposes of
You can do it at the same time, or you can do either one first.
Wear. The emulsion is washed with water according to a conventional method and desalted.
I can do things. Examples of the desalting method include 1) Nudell washing method,
2) Add a flocculant to adjust the pH of the emulsion to the flocculation pH
A method of aggregating the agent, allowing it to settle, and removing the supernatant,
NH ₂A group and / or a carboxyl group, preferably-
NH₂Flocculant, when containing chemically modified gelatin
None, or it may aggregate and settle with a smaller amount added
it can. 3) Aqueous solution in AgX emulsion using ultrafiltration membrane
4) to remove AgX particles by centrifugal sedimentation
A method of lowering and removing the supernatant, 5) a centrifugal filtration method,
6) An electrodialysis method can be mentioned. To those details
Regarding the following documents, Japanese Patent Publication No. Sho 62-27008, JP
Sho 62-113137, JP-A-3-200952,
Misawa, Supplement, Centrifuge, Chemical Industry (1985)
You can refer to the description. In the case of the emulsion of the present invention,
Removes 10-99.9% of dispersion medium using centrifugal filtration
However, a method of adding a new dispersion medium and replacing the dispersion medium is also preferable.
It can be used better. Selection of dispersion medium in the present invention
Can be arbitrarily selected in each step and is shown in claims 1 to 6.
A part of the manufacturing process of the inner latent C / S emulsion.
Can be used for all, but preferably core particles
It is preferably used as a dispersion medium for formation. G. Chemical sensitization The chemical sensitization of the core particle surface and the shell surface of the present invention is
This can be done according to conventional methods. Japanese Patent Application 6-15
The description of No. 0616 can be referred to. A of the present invention
It is preferable that the core grain surface of the gX emulsion is gold-sensitized
New A conventionally known gold sensitizer may be used as the gold sensitizer.
Can be used, for example, chloroauric acid, potassium chloroaure
Glutamic acid, potassium or sodium aurithiocyanate
(Chloroauric acid: SCN^-= 1: 1 to 1: 100 molar ratio),
Examples include bromoauric acid, iodoauric acid, gold sulfide, gold selenide, etc.
For details, refer to the descriptions in the documents below.
You can In addition, (1 equivalent of moles of gold sensitizer / S
The ratio of x equivalent sensitizer added mole number) is preferably 4 to 0.2.
2 to 0.3 is more preferable, and 1.5 to 0.4 is more preferable.
Preferred. The amount added to the AgX emulsion is 10 each.^-2
-10^-7, Preferably 10^-3-10^-7Mol / mol AgX
It is preferable to select the optimum amount from the above.

H. In addition, as a dispersion medium for nucleation and ripening, and as a dispersion medium to be coexisted during growth, one or more kinds of conventionally known water-soluble dispersion media can be selected and used, and gelatin is preferably used. Regarding the conventionally known water-soluble dispersion medium, the following reference and Research Disclosure, Volume 307, Item 30
7105, November, 1989, Japanese Patent Application No. 6-10248
5, Japanese Examined Japanese Patent Publication No. 52-16365, Tadanori Misawa, Water-soluble polymers, Chemical Industry Co. (1987), Japan Society of Polymer Science, New Polymer Materials, One Point 24, Kyoritsu Publishing (1990), Shinji Nagatomo, water soluble And Markets of Polymers, CMC (1984), Ward et al., The Science and Technology
of Gelatin, Academic Press, London (1964),
You can refer to the description of. Dispersion medium concentration is 0.0
A preferable concentration within 1 to 10% by weight, preferably 0.05 to 3% by weight can be selected and used.

Regarding the adsorbed state of the dispersion medium on the AgX particles, one end can be understood by measuring the ionic conductivity of the AgX particles. When the ionic conductivity of interstitial silver ions Agi of AgX particles dispersed in gelatin was measured by the dielectric loss method, the pH of the emulsion was changed from pH7 to pH4 to HNO.
_When lowered with ₃ liquids, the ionic conductivity of cubic AgBr particles increases. This is because the -NH ₂ group of gelatin is -NH ₃ ^+.
It is considered that this is because the adsorptivity to Ag ⁺ on the particle surface is reduced. On the other hand, in the case of octahedral AgBr particles, the ionic conductivity increases due to the pH change. In this case, the Coulomb adsorptivity between --NH ₃ ^{+ of} gelatin and Br ⁻ on the grain surface is increased, and the adsorptivity of gelatin is increased. It is considered that Ag ⁺ can interact with -S- and the like in gelatin only by enhancing the adsorption. Furthermore, the surface Br
^It is conceivable that Agi ⁺ , which was present in balance with the negative charge of ⁻ , becomes unnecessary in terms of Coulomb due to neutralization of the negative charge, and the concentration decreases.

The AgX emulsion grains produced by the method of the present invention can also be blended with one or more other AgX emulsions. The blending ratio can be appropriately selected and used in the range of 1.0 to 0.01.

[0070] There is no particular limitation on the additive that can be added during the grain formation in these emulsions to the coating process, preferably a conventionally known any photographic additives 10 ^-8 ~10 ^-1 mol /
It can be added with the addition amount of molAgX. For example, A
gX solvent, dopant for AgX particles (for example, Group 8 noble metal compounds, other metal compounds, chalcogen compounds, S
CN compound, etc.), dispersion medium, antifoggant, sensitizing dye (blue,
Green, red, infrared, panchromatic, ortho), supersensitizer,
Chemical sensitizers (sulfur, selenium, tellurium, gold and Group 8 noble metal compounds, phosphorus compounds, rhodan compounds, reduction sensitizers singly and in combination of two or more thereof), fogging agents, emulsion precipitants, surfactants Agents, hardeners, dyes, color image forming agents, color photographic additives, soluble silver salts, latent image stabilizers, developers (hydroquinone compounds, etc.), pressure desensitizing agents, matting agents, etc. it can.

The constituent elements of the color diffusion transfer photographic film unit of the present invention are described below in JP-A-6-5937.
No. 7, page 10, right column, line 9 to page 17, left column, line 8 is described in detail. Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

[0072]

【Example】

Example 1 First, a method for preparing a silver halide emulsion will be described. (I) Preparation of Core Emulsion (Ia) Preparation of Core Emulsion (A-1) A reaction vessel contains gelatin solution 1 [1.2 liters of H ₂ O, 1.0 g of gelatin 1 and 0.25 g of KBr, HNO
₃ 3N was put was adjusted] to pH2.0 at a temperature of 4
Keeping the temperature at 0 ° C., stirring the Ag-1 liquid (AgNO ₃ 6
0 g / L) and solution X-1 (1 liter of H ₂ O, KBr 4)
3.2 g, containing 0.8 g of gelatin 1) was added at 30 ml / min for 1 minute to form nuclei. After stirring for 2 minutes, KBr
-1 solution (KBr 100 g / l) was added in an amount of 30 ml, and 1
The temperature was raised to 60 ° C. in 0 minutes. After the first aging for a further 12 minutes, ammonium sulfate solution [(NH ₄ ) ₂ SO ₄ 4 g, H ₂ O 2
0 ml) and NaOH 1N solution were added to adjust the pH to 9.1. After a second ripening for 10 minutes, gelatin solution 2
[25 g of gelatin 2, 130 ml of H ₂ O, KBr
0.15 g is included], and pH is adjusted to 6 with HNO ₃ 3N solution.
It was set to 3. At this time, 96.1% by weight of the dispersion medium becomes gelatin having a phthalation ratio of 96% and a methionine content of 34 μmol / g. The Ag-1 solution and the X-1 solution were simultaneously mixed and added while keeping the pBr at 1.68. 80 ml of Ag-1 solution was added at 6.6 ml / min. Next, Ag-2 liquid (AgNO ₃ 20
0 g / liter) and solution X-2 (146 g / liter) were simultaneously mixed and added while keeping the same pBr. The Ag-2 solution was added at an initial flow rate of 3 ml / min and a linear flow rate acceleration of 0.3 ml / min for 40 minutes. After stirring for 1 minute, 3 ml of the emulsion was sampled, and a transmission electron micrograph image (T
The EM image) was observed. The characteristic values were as follows.
99% or more of the total projected area of all AgX grains (hereinafter referred to as “SA”) are hexagonal tabular grains having a maximum adjacent side ratio of 1 to 1.2, an average thickness of 0.05 μm, and an average diameter of 2.1.
μm, average aspect ratio 42, C.I. V. The value was 0.09. The above emulsion was washed with water by a conventional flocculation method and dispersed using deionized alkali-treated non-modified bone gelatin (methionine content 34 μmol / g) as a dispersion medium to obtain a core emulsion. However, gelatin 1 is a deionized alkali-treated bone gelatin having a weight average molecular weight of 30,000 and a methionine content of 34 μmol / g, and gelatin 2 is gelatin 1.
Refers to gelatin phthalated at a phthalation ratio of 96%. (Ib) Preparation of core emulsion (A-2) The procedure of (A-1) was repeated except that 1.0 g of EPA1 was mixed in gelatin solution 2. When 3 ml of the emulsion was sampled and a TEM image of a replica of the produced grains was observed, the characteristic values were as follows. 99% or more of SA is hexagonal tabular grains having a maximum adjacent side ratio of 1 to 1.2, an average thickness of 0.09 μm, an average diameter of 1.56 μm, an average aspect ratio of about 17, and C.I. V. The value was 0.075. E here
PA1 is a copolymer of (3) -a) -2) formula compound: (4) -a) -4) formula compound: acrylamide = 25: 25: 50% by weight, and has a weight average molecular weight of 33. 1,000.

(Ic) Preparation of Core Emulsion (A-3) The procedure of (A-1) was repeated except that 1.0 g of EPA2 and EPA3 were mixed in the gelatin solution 2. When the TEM image of the replica of the produced particles was observed, the characteristic values were as follows. 99% or more of SA has a maximum adjacent edge ratio of 1
~ 1.2 hexagonal tabular grains with an average thickness of 0.09μ,
Average diameter 1.56 μm, average aspect ratio about 17, C.I.
V. The value was 0.07.

(Id) Preparation of Core Emulsion (A-4) Gelatin solution 1 contains gelatin solution 4 [H ₂ O 1.2 liters, gelatin 2 1.0 g, KBr 0.25 g, HNO ₃ solution. And pH of the solution is adjusted to 5.0 with NaOH solution], and X-1 solution is replaced with X-41 solution (H ₂ O 1 liter, KBr).
It was the same as the preparation of (A-1) except that 43.2 g and 0.8 g of gelatin 2 were included. In this case nucleation,
100% of the dispersion medium during aging and growth has a phthalation ratio of 95
%, The gelatin having a methionine content of 34 μmol / g. When the TEM image of the replica of the produced particles was observed, the characteristic values were as follows. 99% or more of SA is hexagonal tabular grains having a maximum adjacent side ratio of 1 to 1.2 and an average thickness of 0.04.
6 μm, average diameter 2.19 μm, average aspect ratio 4
7.6, C.I. V. The value was 0.085.

Preparation of (Ie) Core Emulsion (A-5)
(Comparative Example) (a) Preparation of core / shell type direct inversion emulsion-1 (comparison)
Example) 0.7% by weight of gelatin containing 0.046M MBr
Aqueous solution (gelatin has an average molecular weight of 20,000
Potassium-treated unmodified gelatin)
1.17M / liter of AgNO containing 0.9% by weight of₃water
Solution and 1.17 M / containing 0.9% by weight of the gelatin
53 cc / min while stirring 1 liter of KBr aqueous solution at 30 ° C
For 66 seconds at the same time. Next, an aqueous gelatin solution
Alkali-on-treated unmodified gelatin 20% by weight solution)
170 cc was added and the temperature was raised to 75 ° C. Ripe for 12 minutes after heating
After formation, 1.06M AgNO₃Add 27 cc of aqueous solution
And NH₃Adjust pH to 10 by adding water (25% by weight)
And aged for 20 minutes. Next is HNO₃Ammonia in water
1.06M / L of AgNO after neutralizing₃Aqueous solution
And a 1.2 M / liter KBr aqueous solution was added to pBr = 1.47.
Accelerated flow rate (end flow rate at start
Double jet addition). AgNO ₃Aqueous solution
Was 500cc. This emulsion was mixed with a conventional flocculant.
Washed with water, add dispersed gelatin and add 800 g
A core emulsion was obtained. The hexagonal tabular grains obtained were average thrown.
The circle equivalent to the shadow area has a diameter of 1.0 μm and an average thickness of 0.19.
μm, 99% or more of the projected area of all silver halide grains is 6
It is occupied by rectangular tabular grains, and changes in the grain size distribution.
The coefficient of motion was 12%.

(II) Preparation of Core / Shell Emulsion (II-a) Preparation of Core / Shell Emulsion (B-1) Core emulsion (A-1) (equivalent to 35 g in terms of AgNO ₃ ) was deionized with 750 cc of water. After 30 g of alkali-modified unmodified bone gelatin (methionine content: 34 μmol / g) was added and the temperature was raised to 75 ° C., 3,6-dithia-1,8-octanediol 0.3 g and sodium benzenethiosulfate 1
0 mg, 2.4 ml of an aqueous solution prepared by dissolving 90 mg of potassium tetrachloroaurate and 1.2 g of potassium bromide in 1000 ml of water, and 15 mg of lead acetate (added as an aqueous solution) were added, and the mixture was heated at 75 ° C. for 1 hour.
The chemical sensitization treatment was performed by heating for 80 minutes. Next, the outer shell is formed. In the same manner as when preparing the core particles, the core particles thus chemically sensitized are
M silver nitrate aqueous solution and 2.5M potassium bromide aqueous solution
The amount and rate of addition of the aqueous potassium bromide solution were adjusted so that Br was 2.2, and the solution was added by the double jet method at an accelerated flow rate (the flow rate at the end was 3 times the flow rate at the start). (The amount of the aqueous silver nitrate solution used was 810 ml.) After adding 0.3 M potassium bromide, this emulsion was washed with water by a conventional flocculation method and gelatin was added. Thus, a hexagonal tabular internal latent image type core / shell emulsion was obtained. The obtained hexagonal tabular grains had an average projected area circle equivalent diameter of 3.1 μm and an average thickness of 0.21 μm, and 95% of the total projected area was occupied by the hexagonal tabular grains. Next, 15 ml of an aqueous solution prepared by dissolving 100 mg of sodium thiosulfate and 40 mg of sodium tetraborate in 1000 ml of water was added to the hexagonal tabular internal latent image type core / shell emulsion,
Add another 20 mg of poly (N-vinylpyrrolidone),
The grain surface was chemically sensitized by heating at 0 ° C. for 100 minutes to prepare a hexagonal tabular internal latent image type direct positive emulsion.

(II-b) Core / shell emulsion (B-2)
Preparation of the core / shell emulsion (B-1) was carried out in the same manner as in the preparation of the core / shell emulsion (B-1) except that the core emulsion was changed from (A-1) to (A-2). It was (II-c) Preparation of core / shell emulsion (B-3) In the same manner as in the preparation of core / shell emulsion (B-1), the core emulsion was changed from (A-1) to (A-3). To prepare a core / shell emulsion (B-3). (II-d) Preparation of core / shell emulsion (B-4) In the same manner as in the preparation of core / shell emulsion (B-1), the core emulsion was changed from (A-1) to (A-4). Core / shell emulsion (B-4) was prepared. (II-e) Preparation of core / shell emulsion (B-5) (comparative example) In preparation of core / shell emulsion (B-1), the core emulsion was changed from (A-1) to (A-5). A core / shell emulsion (B-5) was prepared in the same manner except for the above. The sizes and shapes of the obtained parallel twin-containing tabular grains B-1 to B-5 are shown in Table 2 below.

[0078]

[Table 1]

Using the above core / shell emulsions B-1 to B-5, photosensitive elements 1 to 5 having the constitution shown in Table 2 below were prepared.

[0080]

[Table 2]

[0081]

[Table 3]

[0082]

[Table 4]

[0083]

[Table 5]

[0084]

[Chemical 9]

[0085]

[Chemical 10]

[0086]

[Chemical 11]

[0087]

[Chemical 12]

The cover sheet was prepared as follows. The following layers were coated on a polyethylene terephthalate transparent support containing a gelatin-primed anti-light piping dye. (1) 10.4 g / m ² and 1,4 of an acrylic acid / butyl acrylate (molar ratio 8: 2) copolymer having an average molecular weight of 50,000
4-bis (2,3-epoxypropoxy) -butane 0.
Neutralization layer containing 1 g / m ² . (2) Acetyl cellulose with an oxidation degree of 51% 4.3 g / m ² ,
A neutralization timing layer containing 0.2 g / m ² of poly (methyl vinyl ether co-monomethyl maleide). (3) Styrene / butyl acrylate / acrylic acid / N-
Methylol acrylamide weight ratio 49.7 / 42.3
The polymer latex emulsified at a ratio of / 4/4 and the polymer latex obtained by emulsifying and weighting methylmethacrylate / acrylic acid / N-methylolacrylamide at a ratio of 93/4 by weight have a solid content ratio of 6: 4. A layer containing 2.5 g / m ^{2 of the} total solid content by blending so that (4) A layer containing 1 g / m ² of gelatin.

The formulation of the alkaline treatment composition is shown below. 1-p-tolyl-4-hydroxymethyl-4-methyl-3-pyrazolidone 10.0 g methylhydroquinone 0.18 g 5-methylbenzotriazole 3.0 g sodium sulfite (anhydrous) 0.2 g benzyl alcohol 1.5 cc Carboxymethyl cellulose Na salt 58 g Carbon black 150 g Potassium hydroxide (28% aqueous solution) 200 cc Water 680 cc The treatment liquid of the above composition was charged 0.8 g each in a "pressure rupturable container". After exposing the photosensitive elements 1 to 5 from the emulsion side through a continuous gray wedge, they are superposed on the cover sheet, and the processing solution is spread between both materials by using a pressure roller so as to have a thickness of 75 μm. did. The treatment was carried out at 25 ° C., and after 10 minutes, the transfer density was measured with a color densitometer. The results are shown in Table-3.

[0090]

[Table 6]

As a result, as the protective colloid at the time of grain formation, gelatin in which the amino group was chemically modified was used in the region (a) of FIG. A color diffusion transfer light-sensitive material in which a high S / N ratio was achieved by a tabular grain core / shell emulsion was obtained.

Example 2 A similar method was used except that the phthalated gelatin used in the gelatin solution 4 and the X-41 solution in the preparation of the core emulsion A-4 of Example 1 was replaced with the gelatins 21 to 26 shown in Table-4. To prepare core emulsions A-21 to 26,
Core / shell emulsions B-21 to 26 were prepared in the same manner except that the core emulsion A-4 was replaced with the core emulsions A-21 to 26 in the preparation of the shell emulsion B-4. In the same manner as in Example 1, the emulsions of the 19th, 13th and 7th layers were replaced with core / shell emulsions B-21 to 26 to provide photosensitive elements 21 to 26.
Was prepared and evaluated in the same manner as in Example 1. Table of the results
5 shows. Most preferable photographic properties were obtained when gelatin in the region of a ₁ , preferably a ₂ , and more preferably a ₃ in FIG. 1 was used.

[0093]

[Table 7]

[0094]

[Table 8]

[Brief description of drawings]

FIG. 1 Definition of gelatin of the present invention

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G03C 8/50 G03C 8/50

Claims (7)

[Claims] 1. A total of 75 to 100% of the projected area of silver halide grains is 0.03 to 0.03 in thickness, which has undergone at least nucleation, ripening and growth in a dispersion medium solution containing water and a dispersion medium.
A method for producing a core / shell type direct inversion emulsion of tabular grains having an aspect ratio (diameter / thickness) of 2 to 50 and having a dispersion ratio of 30 μm in a part or all of a silver halide grain formation process. -100% by weight is gelatin having the following characteristics (a):
A method for producing an internal latent image type direct positive silver halide emulsion which has not been fogged in advance. (A) The relationship between the percentage (%) of the number of chemically modified --NH ₂ groups in the gelatin and the methionine content of gelatin is in the region a ₁ of FIG. 2. The dispersion medium solution is a polymer having repeating units of polyalkylene oxide and has a molecular weight of 500 to 1.
0 ⁶ a is HPAO [formula (1) -a) or (1)
-B)] or PEOD [general formula (2)-
represented by any of a) to -f)] is 0.00
The method for producing a silver halide emulsion according to claim 1, wherein the content is 1 g / liter or more and 100 g / liter or less. Embedded image Here, R ⁰ is H or a hydrocarbon having 1 to 10 carbon atoms and having at least one polar group, and preferably H.
R represents an alkylene group having 3 to 10 carbon atoms.
n and m represent the average number of repeating units and are values of 4 or more satisfying the above-mentioned molecular weight regulation. Embedded image Where LPU is HO-HPEOU-group and HO-LP
Refers to a lipophilic group other than the AOU- group, and includes a substituted or unsubstituted alkyl group, alkenyl group, aryl group, heterocyclic group,
An alkoxy group, an aryloxy group, an acyl group, an acylamino group, an alkylthio group, an arylthio group, an alkoxycarbonyl group, an aryloxycarbonyl group, and an alicyclic group. Incidentally, HPEOU and LPAOU have the same meanings as in the general formula (1). 3. The dispersion medium solution contains 0.01 g / liter or more and 100 g / liter or less of at least one polymer containing 1% by weight or more of the repeating unit of the monomer represented by the general formula (3), The method for producing a silver halide emulsion according to claim 1, wherein the polymer has a molecular weight of 500 to 10 ⁶ . Embedded image In the formula, R ¹ represents H or a lower alkyl group, and R ² represents a monovalent substituent. R ³ represents an alkylene group having 3 to 10 carbon atoms, and L represents a divalent substituent. n represents the average number of repeating units and is 4 to 600. 4. The dispersion medium solution contains 0.01 g / liter of a copolymer containing 1% by weight or more of each of at least two kinds of the monomer represented by the general formula (3) and the monomer represented by the general formula (4). The above is contained, and the molecular weight of the copolymer is 5
The method for producing a silver halide emulsion according to claim 1, wherein the amount is 00 to 10 ⁶ . Formula _{(4) CH 2 = C (} R 4) -L '- in _{(CH 2 CH 2 O) m} -R 5 Formula, R ⁴ represents H, a lower alkyl group, R ⁵ is a monovalent substituent And L'represents a divalent linking group. m represents the average number of repeating units and is 4 to 600. 5. The dispersion medium solution comprises at least one polymer containing 1% by weight or more of a repeating unit represented by the following general formula (5) and 1 repeating unit represented by the general formula (6). 0.01 g / each of one of the polymers containing at least wt%
2. The method for producing a silver halide emulsion according to claim 1, wherein the content of liter is 100 g / liter or less and the polymer has a molecular weight of 500 to 10 ⁶ . Formula (5) - (R-O ) n - Formula _{(6) - (CH 2 CH} 2 O) m - wherein, R represents an alkylene group having 3 or more carbon atoms, 10 or less. n and m represent the average number of repeating units and are values of 4 or more that satisfy the molecular weight regulation. 6. A repeating unit represented by the general formula (5)
A polymer having a monomer of the following general formula (7)-(a)
Vinyl polymer as a constituent and general formula (7)-
At least one type of polyurethane selected from the polyurethane of (b)
And a repeating unit represented by the general formula (6)
To form a monomer of the following general formulas (7)-(c).
A vinyl polymer as a component, a polymer represented by the general formula (7)-(d)
Polyurethane and substituted or unsubstituted polyethylene
At least one polymer selected from recalls
A silver halide emulsion according to claim 1, characterized in that
Build method. General formula (7) -a) CH₂= C (R¹) -L- (RO)_n-R² General formula (7) -b)-[O- (R-O)_n]_x− ・ − [O-R¹¹-O)_y− ・ − [CONH-R¹²-NHCO] _Z -General formula (7) -c) CH₂= C (R^Four) -L '-(CH₂CH₂O)_m-R^Five General formula (7) -d)-[O- (CH₂CH₂O)_m]_{X '}− ・ − 〔O-R¹³-O]_{y '}− ・ − [CONH-R¹⁴-NHCO]_{Z '} -In the formula, n and m represent the average number of repeating units and are 4 to 600.
Is. R¹, R^FourIs H or a lower alkyl having 1 to 4 carbon atoms
Represents a kill group. R², R^FiveIs H or has 1 to 20 carbon atoms
It represents a monovalent substituent. L and L'represent a divalent linking group.
R¹¹, R¹²Represents a divalent linking group and has 1 to 20 carbon atoms.
Ruylene group, phenylene group having 6 to 20 carbon atoms, or charcoal
It represents an aralkylene group having a prime number of 7 to 20. x, y, z,
x ', y', z'represent the weight percentage of each component, x,
x'is 1 to 70, y and y'is 1 to 70, and z and z'are 20.
Represents ~ 70. Where x + y + z = 100, x '+ y'
+ Z '= 100. R is an alkyle having 3 to 10 carbon atoms
Represents a group. 7. A photosensitive sheet having on a support at least one silver halide emulsion layer in combination with at least one dye image-forming substance, and a development between the photosensitive sheet and a second support. In a color diffusion transfer photographic film unit containing an alkaline processing composition adapted to be used, at least one of said silver halide emulsion layers is a pre-unfogged internal latent image according to claims 1-6. A color diffusion transfer photographic film unit containing a mold direct positive silver halide emulsion.