JP2001100349A - Silver halide emulsion and method for manufacturing same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the silver halide emulsion capable of preparing flat silver halide grains extremely small in thickness and high in an aspect ratio and monodispersing the grain size. SOLUTION: The flat silver halide grains comprise flat silver halide grains occupying>=50% of the projection areas of the total silver halide grains and having a thickness of <=0.3 μm, and a dispersion medium containing a gelatin substituted by at least one 4-16C aliphatic hydrocarbon or an aromatic hydrocarbon having at least one 4-16C aliphatic hydrocarbon group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a light-sensitive silver halide emulsion and a method for producing the same. More specifically, the present invention relates to a method for producing thin tabular grains having high uniformity.

[0002]

2. Description of the Related Art Tabular silver halide grains (hereinafter referred to as "tabular grains") have the following photographic characteristics: 1) Ratio of surface area to volume (hereinafter referred to as specific surface area).
And a large amount of sensitizing dye can be adsorbed on the surface, so that the color sensitization sensitivity is relatively higher than the intrinsic sensitivity. 2) When an emulsion containing tabular grains is coated and dried, the grains are arranged parallel to the surface of the support, so that the thickness of the coating layer can be reduced and the photographic light-sensitive material has good sharpness. 3) In a radiographic system, when a sensitizing dye is added to tabular grains, silver halide crossover light can be significantly reduced, and deterioration of image quality can be prevented. 4) An image with low light scattering and high resolution can be obtained. 5) The green photosensitive layer or
When used in the red photosensitive layer, the yellow filter can be removed from the emulsion. Since it has many advantages as described above, it has been conventionally used for high-sensitivity commercially available photosensitive materials. JP-B-6-44132 and JP-B-5-16015 disclose tabular grain emulsions having an aspect ratio of 8 or more. The aspect ratio here is indicated by a ratio of a diameter to a thickness of a tabular grain. Further, the diameter of a grain refers to the diameter of a circle having an area equal to the projected area of the grain when the emulsion is observed with a microscope or an electron microscope. The thickness is indicated by the distance between two parallel surfaces constituting the tabular silver halide. Japanese Patent Publication No. 4-36374 discloses that at least one of a green emulsion layer and a red emulsion layer has a thickness of 0.3.
There is described a color photographic light-sensitive material in which sharpness, sensitivity and graininess are improved by using tabular grains having a diameter of less than μ and a diameter of 0.6 μ or more. However, in recent years, high sensitivity and small format of silver halide photosensitive materials have been advanced,
There is a strong demand for color photographic materials having higher sensitivity and improved image quality. Therefore, silver halide grain emulsions with higher sensitivity and better graininess are required, and conventional tabular silver halide emulsions have to meet these demands.
It was insufficient, and further improvement in performance was desired.

Further, the tabular grains having a higher aspect ratio have a larger specific surface area, so that the above-mentioned advantages of the tabular grains can be greatly utilized. That is, by adsorbing more sensitizing dyes to a larger surface area, it becomes possible to obtain high sensitivity by increasing the amount of light absorption per particle. Therefore, many methods for preparing thinner tabular grains have been studied. Japanese Patent Publication No. 5-12696 discloses a method for preparing thin tabular grains by using methionine groups in gelatin and oxidized and invalidated gelatin as a dispersion medium. JP-A-8-82883 discloses a method for preparing thin tabular grains using gelatin in which amino groups and methionine groups have been invalidated as a dispersing medium. In addition, JP 10-1
No. 48897 discloses a method in which amino groups in gelatin are chemically modified to prepare thin tabular grains using gelatin having at least two or more carboxyl groups introduced therein as a dispersion medium.

On the other hand, as described above, in order to obtain high sensitivity, it is necessary to adsorb more dye to such tabular grains having a small thickness and a higher aspect ratio. The big problem of agglomeration arises. What is aggregation?
A phenomenon in which two or more tabular grains gather to form secondary grains. When this agglomeration occurs, photographic properties such as deterioration of graininess, decrease in density after development, and increase in fog are caused.
Agglomeration is a phenomenon in which the main surfaces of tabular grains coalesce, and it is likely to occur as the aspect ratio of the tabular grains increases, as the amount of adsorbed dye increases, that is, as the coverage of the adsorbed dye on the particle surface increases. It is described in Japanese Patent Application No. 10-293987 that this problem can be solved by using an alkali-treated bone gelatin containing a component having a molecular weight of 280,000 or more as 30% or more as a dispersion medium.

Silver chloride is inherently stable on the (100) plane. Therefore, in order to form tabular grains having (111) as the main surface, (111)
It is necessary to use a so-called crystal habit controlling agent for stabilizing the surface during grain formation. The use of a pyridinium cation as an effective (111) crystal phase controlling agent is disclosed in JP-A-2-32, JP-A-77-146891.
Issue. The patent discloses that these crystal habit-controlling agents are used for silver chloride to prepare (111) main surface tabular grains of silver chloride. However, thin tabular grains can be prepared using these control agents as well as silver bromide or silver iodobromide tabular grains. JP-A-8-220664 discloses (11
1) It is disclosed that tabular grains having long dislocation lines can be prepared using a plane crystal phase controlling agent. Also Japanese Patent Laid-Open No. 10-104769
Discloses preparing thinner tabular grains using a (111) crystal habit modifier. However, the method of preparing thin tabular grains using a control agent is not yet sufficient. In addition, the problem of aggregation of tabular grains having a very small thickness and a high aspect ratio has not been solved yet.

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a method which enables preparation of tabular grains having a very small thickness and a high aspect ratio and enables monodispersion of the grain size. is there.

[0007]

The object of the present invention has been attained by the following method. (1) In a photosensitive silver halide emulsion composed of silver halide grains and a dispersion medium, 50% or more of the total projected area of all silver halide grains has an aspect ratio of 3 or more and a thickness of 0.3 μm or less. Silver tabular grains containing gelatin substituted with at least one aliphatic hydrocarbon having 4 to 16 carbon atoms or at least one aromatic hydrocarbon having an aliphatic hydrocarbon group having 4 to 16 carbon atoms; A photosensitive silver halide emulsion comprising: (2) A photosensitive silver halide emulsion comprising silver halide grains and a dispersion medium, wherein 50% of the total projected area of all silver halide grains
The above is the aspect ratio is 3 or more, the thickness is 0.3 μm or less,
In a method for producing a photosensitive silver halide emulsion comprising silver halide tabular grains whose main surface is a (111) plane, the tabular grains are formed of at least one aliphatic hydrocarbon having 4 to 16 carbon atoms, or at least one aliphatic hydrocarbon having 4 to 16 carbon atoms. At least one compound represented by the following general formula (I), (II) or (III) in a dispersion medium containing gelatin substituted with an aromatic hydrocarbon having an aliphatic hydrocarbon group having 4 to 16 carbon atoms. A method for producing a photosensitive silver halide emulsion, which is prepared in the presence of one kind.

[0008]

Embedded image

In the formula, R₁Represents an alkyl group, an alkenyl group,
Represents an aralkyl group;_Two, R_Three, R _Four, R_FiveAnd R₆
Represents a hydrogen atom or a substituent, respectively. R_TwoAnd R_Three,
R_ThreeAnd R_Four, R_FourAnd R_Five, R_FiveAnd R₆May be fused
No. Where R_Two, R_Three, R_Four, R_FiveAnd R₆Less of
And one represents an aryl group. X^-Represents the counter anion
You.

[0010]

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In the formula, A ₁ , A ₂ , A ₃ and A ₄ represent a group of non-metallic atoms for completing a nitrogen-containing heterocyclic ring, and they may be the same or different. B represents a divalent linking group. m represents 0 or 1. R ₁ and R ₂ each represent an alkyl group. X represents an anion. n is 0 or 1
In the case of an inner salt, n is 0. (3) Halogenation containing at least 50% mol of silver bromide, at least 50% of the total projected area of all grains having an aspect ratio of 8 or more, and a main surface having a thickness of 0.05 μm or less being a (111) plane. The method for producing a photosensitive silver halide emulsion according to the above (1) or a silver halide emulsion according to the above (2), which is a silver tabular grain. (4) Silver halide containing at least 50 mol% of silver chloride, at least 50% of the total projected area of all grains has an aspect ratio of 8 or more, and a main surface having a thickness of 0.3 μm or less is a (111) plane. The method for producing a photosensitive silver halide emulsion according to the above (1) or a photosensitive silver halide emulsion according to the above (2), wherein the emulsion is tabular grains. (5) A mixer is provided outside a reaction vessel for causing nucleation and / or grain growth of silver halide grains, and an aqueous solution of a water-soluble silver salt and an aqueous solution of a water-soluble halide are supplied to the mixer and mixed. Forming silver halide fine grains, immediately supplying the fine grains to a reaction vessel, and causing nucleation and / or growth of the silver halide grains in the reaction vessel. A method for producing a silver halide emulsion or the photosensitive silver halide emulsion of the above (2).

The tabular silver halide grains (hereinafter, referred to as "tabular grains") in the present invention have two opposing parallel main surfaces and have a circle equivalent diameter of the main surface (the same projected area as the main surface). Are larger than the distance of the main surface (that is, the thickness of the particle) by a factor of two or more. The average grain diameter / grain thickness ratio of the emulsion having tabular grains of the present invention is from 3 to 3.
100 is preferable, 5 to 100 is more preferable, and 8 to 100 is more preferable. Here, the average grain diameter / grain thickness is obtained by averaging the grain diameter / thickness ratio of all tabular grains, but as a simple method,
It can also be determined as a ratio between the average diameter of all tabular grains and the average thickness of all tabular grains.

The tabular grains of the present invention have a diameter (equivalent to a circle) of 0.1.
It is 3 to 20 μm, preferably 0.5 to 15 μm, and more preferably 0.5 to 10 μm. Particle thickness is 0.3
μm or less, preferably 0.1 μm, and more preferably 0.05 to 0.01 μm. The measurement of the particle diameter and the particle thickness in the present invention can be obtained from an electron micrograph of the particles as described in US Pat. No. 4,434,226. That is, the thickness of the particles is measured by evaporating a metal from the oblique direction of the particles together with the reference latex, measuring the length of the shadow on an electron micrograph, and calculating with reference to the length of the shadow of the latex. Can be more easily known.

The main surface of the tabular grain of the present invention is (11).
They are broadly divided into 1) and (100). A tabular grain having a (111) plane as a main surface is a general term for silver halide grains having one twin plane or two or more parallel twin planes. The twin plane refers to the (111) plane when ions at all lattice points on both sides of the (111) plane are in a mirror image relationship.
When viewed from above, the tabular grains have a triangular shape, a hexagonal shape, or a shape between them, and these have a rounded shape. Hexagonal, intermediate between, rounded tabular grains have mutually parallel outer surfaces with rounded corners.

US Pat. Nos. 4,434,226 and 4,439,520 disclose a method for producing (111) main surface type tabular grains.
Nos. 4,441,310, 4,433,048, 44
No. 14,306, No. 4,459,353 disclose the production method and use technology thereof. Also, Japanese Patent Application Laid-Open No. Hei 6-214331
As disclosed in U.S. Pat. No. 5,085,097, once nucleation is performed to obtain a seed crystal, it is adjusted to pH, p, and pH for convenient growth.
By setting conditions such as Ag, silver and a halogen solution are added for growth, and tabular grains can be formed. As a preferable method, tabular grains are formed by adding silver halide fine particles instead of adding a silver salt aqueous solution and a halide aqueous solution to a reaction vessel holding a protective colloid aqueous solution. This method is described in US Pat.
The technology is disclosed in Japanese Patent Application Laid-Open Nos. JP-A-Heisei 1-183644, JP-A-2-4435, JP-A-2-43535 and JP-A-2-68538. As a method for supplying iodine ions in forming tabular grains, a fine grain silver iodide (having a grain size of 0.1 μm or less, preferably 0.06 μm or less) emulsion may be added. It is preferable to use the manufacturing method disclosed in US Pat. No. 4,879,208.

In the present invention, it is preferable to use monodisperse tabular grains. In this regard, JP-A-63-11928
And Japanese Patent Publication No. 5-61205 disclose monodisperse hexagonal tabular grains, and JP-A-1-131541 discloses circular monodisperse tabular grains. In JP-A-2-838, more than 95% of the total projected area is occupied by tabular grains having two twin planes parallel to the main surface, and the size distribution of the tabular grains is monodisperse. Certain emulsions have been disclosed. EP 514 742 A discloses tabular grain emulsions prepared using a polyalkylene oxide block copolymer and having a coefficient of variation in grain size of 10% or less.

The following patent discloses silver chloride or a (111) plate having a high silver chloride content used in the present invention. U.S. Patent No. 4,414,306, U.S. Patent No. 4,400,463, U.S. Patent No. 4,713,323
No. 4,783,398; U.S. Pat.
No. 491, U.S. Pat. No. 4,983,508, U.S. Pat.
No. 804621, US Pat. No. 5,389,509, US Pat. No. 5,217,858, US Pat. No. 5,460,934.

The silver bromide (111) tabular grains used in the present invention are described in the following patents. U.S. Pat. No. 4,425,425, U.S. Pat. No. 4,425,426,
U.S. Pat. No. 4,443,426; U.S. Pat. No. 4,439,520
No. 4,414,310; U.S. Pat.
048, U.S. Pat. No. 4,647,528, U.S. Pat.
No. 665012, U.S. Pat. No. 4,672,027, U.S. Pat. No. 4,678,745, U.S. Pat. No. 4,684,607,
U.S. Pat. No. 4,593,964, U.S. Pat.
6, U.S. Pat. No. 4,722,886, U.S. Pat.
5617, U.S. Pat. No. 4,755,456, U.S. Pat. No. 4,806,461, U.S. Pat. No. 4,801,522, U.S. Pat. No. 4,835,322, U.S. Pat. No. 4,839,268.
No. 4,940,014, U.S. Pat.
No. 015, U.S. Pat. No. 4,977,074, U.S. Pat.
No. 98350, U.S. Pat. No. 5,061,609, U.S. Pat. No. 5,061,616, U.S. Pat. No. 5,068,173,
U.S. Pat. No. 5,132,203, U.S. Pat.
No. 8, US Pat. No. 5,334,469, US Pat.
No. 4495, US Pat. No. 5,358,840, US Pat. No. 5,372,927.

Regarding the (100) flat plate used in the present invention, US Pat. No. 4,386,61 which is described in the following patents:
No. 56, U.S. Pat. No. 5,275,930, U.S. Pat.
No. 92632, U.S. Pat. No. 5,314,798, U.S. Pat. No. 5,320,938, U.S. Pat. No. 5,319,635, U.S. Pat.
No. EP 737887, JP-A-6-30864
No. 8, JP-A-9-5911.

The halogen composition of the tabular grains includes silver iodobromide, silver chloroiodobromide, silver iodochloride, silver iodobromochloride, silver chlorobromide and silver chloride. Regarding the structure relating to the halogen composition of the tabular grains of the present invention, X-ray diffraction, EPMA (XMA
Method (which scans silver halide grains with an electron beam to detect silver halide composition), ESCA
(Method of irradiating X-rays to split photoelectrons emitted from the particle surface) and the like can be confirmed. In the present invention, the particle surface refers to a region up to a depth of about 50 A from the surface, and the halogen composition thereof is usually ES.
It can be measured by the CA method. The inside of the particle refers to a region other than the above-described surface region.

The gelatin used in the present invention has 4 carbon atoms.
Gelatin substituted with an aliphatic hydrocarbon having from 16 to 16 or an aromatic hydrocarbon having an aliphatic hydrocarbon group having from 4 to 16 carbon atoms. At the time of introducing these hydrocarbons, it is preferable to simultaneously introduce an acidic group in order to maintain the water solubility of gelatin. Examples of the acidic group include a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, and a nitric acid group. However, any group capable of donating a proton may be used. The aliphatic hydrocarbon having 4 to 16 carbon atoms may be branched, may be cyclic alkyl, may be substituted by another group, or may be unsaturated. Research on the interfacial science properties of the gelatin of the present invention was conducted by the Journal of Colloid and Interface Scie
nce 193, 172-177 (1997). The study shows that substituting alkyl having 2 to 12 carbon atoms to increase the lipophilicity of gelatin reduces the surface tension of the aqueous solution. German Patent 1972
No. 1238 discloses that gelatin modified with alkyl succinic acid is used for an ink jet receiving paper. The use of the gelatin of the present invention in the preparation of an oil-in-water type emulsion was able to obtain smaller oil droplets.
Colloid and Interface Science 200 235-240 (199
8). All of these use the fact that the lipophilicity of gelatin is increased and the surface tension (interfacial tension) of a gelatin solution is reduced. In the present invention, by introducing an aliphatic hydrocarbon, the lipophilicity of gelatin is increased, and as a result, the adsorptivity of gelatin to silver halide emulsion grains is increased, preferably by simultaneously introducing an acidic group. The purpose is to increase the negative charge of gelatin and maintain its water solubility. In the latter case, when the amino group which is a basic group of gelatin is substituted and an acidic group is introduced therein, the negative charge of gelatin can be more effectively increased. Due to the increase of the negative charge, the compound represented by the general formula (I), (II) or (III) used in the present invention is a silver halide grain by the gelatin of the present invention which is effectively adsorbed on the grains because they are cations. And the effect can be effectively exhibited with a smaller amount of addition.

The preparation of the gelatin of the present invention is disclosed, for example, by reacting dodecyl succinic anhydride and gelatin in an aqueous solution while controlling the temperature and pH, as disclosed in German Patent No. 19721238. Have been. In this case, one carboxyl group of succinic acid reacts with the amino group of lysine of gelatin, so that the amino group of gelatin disappears,
Instead, another carboxyl group of succinic acid is introduced. (Dodecyl amber gelatin) As a result, the amino group of gelatin is converted into a carboxyl group, and an alkyl group having 12 carbon atoms is introduced. Similarly, the gelatin of the present invention can be prepared in various combinations. For example, the amino group of lysine of gelatin is replaced with alkyl phthalic anhydride,
It may be substituted with an alkyl trimellitic anhydride. Of course, the object of the present invention is achieved even if the introduction of the acidic group and the introduction of the aliphatic hydrocarbon are performed separately. For example, the amino group of lysine is replaced with succinic acid, phthalic acid, or trimellitic acid, and another residue in gelatin, such as the carboxyl group of aspartic acid or glutamic acid, is esterified or amidated, or imidazole is used. The group may be replaced by an aliphatic hydrocarbon by an ethoxyformylation reaction. That is, the acidic group and the aliphatic hydrocarbon do not need to be connected.

The original gelatin used in the present invention may be either alkali-treated or acid-treated, but usually alkali-treated gelatin is often used. In particular, it is preferable to use alkali-treated gelatin that has been subjected to deionization treatment or ultrafiltration treatment in which impurity ions and impurities have been removed. In addition to alkali-treated gelatin, acid-treated gelatin, derivative gelatin such as phthalated gelatin and esterified gelatin, low molecular weight gelatin (molecular weight of 1,000 to 80,000, specifically, gelatin decomposed with enzymes, hydrolyzed with acid and / or alkali) Decomposed gelatin, gelatin decomposed by heat can be mentioned),
High molecular weight gelatin (molecular weight of 110,000 to 300,000) Use of gelatin having a methionine content of 50 μmol / g or less, gelatin having a tyrosine content of 20 μmol / g or less, oxidized gelatin, and gelatin in which methionine is inactivated by alkylation. Or a mixture of two or more of them. The high molecular weight gelatin is disclosed in Japanese Patent Application No. 9-345605. In the present invention, the amount of gelatin used in the grain forming step is 1 to 60 g / mole of silver, preferably 3 to 40 g. The concentration of gelatin in the chemical sensitization step of the present invention is preferably 1 to 100 g / silver mole, and more preferably 1 to 70 g / silver mole. Further, the gelatin of the present invention can be used in combination with the above gelatin. The gelatin of the present invention may be added at any point during grain formation, but is preferably added after nucleation. The addition amount is 1 to the total dispersion medium during the particle formation.
0% or more, preferably 30%, more preferably 50% or more.

The details of the compound represented by formula (I), (II) or (III) used for forming the (111) main surface type tabular grains in the present invention will be described. In the general formula (I), R ₁ is a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms (for example, methyl group, ethyl group, isopropyl group, t-butyl group, n-octyl group, n-decyl) Group, n
-Hexadecyl group, cyclopropyl group, cyclopentyl group, cyclohexyl group), alkenyl group having 2 to 20 carbon atoms (e.g., allyl group, 2-butenyl group, 3-pentenyl group), aralkyl group having 7 to 20 carbon atoms (e.g., Benzyl group, phenethyl group). Each group represented by R ₁ may be substituted. As the substituent, the following R ₂
Displaceable groups represented by to R ₆ may be mentioned.

R ₂ , R ₃ , R ₄ , R ₅ and R ₆ may be the same or different and each represents a hydrogen atom or a group capable of substituting it. Substitutable groups include the following. Halogen atom, alkyl group, alkenyl group, arakinyl group, aralkyl group, aryl group, heterocyclic group (for example, pyridyl group, furyl group, imidazolyl group, piperidyl group, morpholino group, etc.), alkoxy group, aryloxy group, amino group An acylamino group, a ureido group, a urethane group, a sulfonylamino group, a sulfamoyl group, a carbamoyl group, a sulfonyl group, a sulfinyl group, an alkyloxycarbonyl group, an acyl group,
Acyloxy group, phosphoramide group, alkylthio group, arylthio group, cyano group, sulfo group, carboxy group, hydroxy group, phosphono group, nitro group, sulfino group, ammonio group (for example, trimethylammonio group, etc.), phosphonio group, And a hydrazino group. These groups may be further substituted. R ₂ and R ₃ , R ₃ and R ₄ , R
₄ and R ₅ , and R ₄ and R ₆ may be fused to form a quinoline ring, isoquinoline ring or acridine ring. X ^- represents a counter anion. Examples of the counter anion include a halogen ion (a chloride ion and a bromine ion), a nitrate ion, a sulfate ion, a p-toluenesulfonic acid ion, and a trifluoromethanesulfonic acid ion. Preferably in formula (I), R ₁ represents an aralkyl group, R _2, R
_At least one of ₃ , R ₄ , R ₅ and R ₆ represents an aryl group. More preferably, in the general formula (I), R ₁
Represents an aralkyl group, R ₄ represents an aryl group, and X ⁻
Represents a halogen ion. Examples of these compounds are disclosed in Japanese Patent Application No. Hei.
No. 333780 describes crystal habit control agents 1 to 29, but the present invention is not limited thereto.

Next, the compounds represented by the general formulas (II) and (II)
The compound (I) will be described in detail. A ₁ , A ₂ , A
₃ and A ₄ each represent a nonmetallic element for completing a nitrogen-containing hetero ring, and may contain an oxygen atom, a nitrogen atom, a sulfur atom, or a benzene ring may be condensed. A ₁ ,
The hetero ring composed of A ₂ , A ₃ and A ₄ may have a substituent, and each may be the same or different. As a substituent, an alkyl group, an aryl group, an aralkyl group, an alkenyl group, a halogen atom, an acyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, a sulfo group, a carboxy group, a hydroxy group, an alkoxy group, an aryloxy group, an amide group, It represents a sulfamoyl group, a carbamoyl group, a ureido group, an amino group, a sulfonyl group, a cyano group, a nitro group, a mercapto group, an alkylthio group, or an arylthio group. Preferred examples are A ₁ , A ₂ ,
A ₃ and A ₄ can be a 5- to 6-membered ring (for example, a pyridine ring, an imidazole ring, a thiazole ring, an oxazole ring, a pyrazine ring, a pyrimidine ring, and the like). A more preferred example is a pyridine ring.
B represents a divalent linking group. Alkylene divalent linking group, arylene, _{alkenynes, -SO 2 -, - SO -} , - O
-, - S -, - CO -, - N (R 2) - (R 2 is an alkyl group,
Represents an aryl group or a hydrogen atom. ) Alone or in combination. Preferred examples of B include alkylene and alkenylene. R ₁
And R ₂ represent an alkyl group having 1 to 20 carbon atoms. R
₁ and R ₂ may be the same or different. The alkyl group represents a substituted or unsubstituted alkyl group, and the substituent is the same as the substituents described as the substituents for A ₁ , A ₂ , A ₃ and A ₄ . As a preferred example, R ₁ and R ₂ each represent an alkyl group having 4 to 10 carbon atoms. A more preferred example is a substituted or unsubstituted aryl-substituted alkyl group. X represents an anion. For example, they represent chlorine ion, bromine ion, iodine ion, nitrate ion, sulfate ion, p-toluenesulfonate, and oxalate. n represents 0 or 1, and in the case of an inner salt, n represents 0
It is. Specific examples of the compound represented by formula (II) or (III) are disclosed in JP-A-2-32 (Compound Examples 1 to 42), but the present invention is limited to these compounds. Not something.

The compound represented by the general formula (I), (II) or (III) used in the present invention is a compound (11) of a silver halide crystal.
1) The property of selectively adsorbing on the surface is remarkable, and this is called a (111) crystal habit controlling agent. When these compounds are present in the formation of (111) main surface type tabular grains, the compound selectively adsorbs to the main surface of the tabular grains to suppress the growth of the tabular grains in the thickness direction, and as a result, thin tabular grains are formed. What can be obtained is that JP-A-10-104769 discloses that a thinner tabular grain is prepared by using a (111) crystal phase controlling agent. However, in that case, obtaining a very thin silver bromide or silver iodobromide slab requires a very large amount of twinning control agent, which results in a very high concentration of the control agent in the solution and a re-control. Fine grains due to nucleation appeared, and an emulsion could be prepared only with a very small amount of silver nitrate. When the gelatin of the present invention is used, the adsorption of the crystal habit controlling agent occurs very efficiently, the concentration of the crystal habit controlling agent in the solution can be lowered, and the conventional problems can be solved. As described above, this effect is due to the fact that the gelatin of the present invention has a very large number of acidic groups and its strong lipophilicity, so that a large amount of gelatin is adsorbed. This is due to the presence of many acidic groups and the attraction of the crystal habit modifier, which is a cation of the present invention, to the particles in a larger amount.

In producing a silver halide emulsion according to the present invention, there are no particular restrictions on the additives that can be added from the time of grain formation to the time of coating. Also, combinations with all known techniques can be used. Regarding these, the description in the following literature can be referred to.
A silver halide solvent can be used to promote the growth during the crystal formation process and to make the chemical sensitization effective at the time of grain formation and / or chemical sensitization. Examples of frequently used silver halide solvents include water-soluble thiocyanates, ammonia, thioethers and thioureas. For example, thiocyanates (U.S. Pat. Nos. 2,222,262, 2,448,534, and 33)
20069), ammonia, thioether compounds (for example, US Pat. Nos. 3,271,157 and 357)
No. 4628, No. 3704130, No. 4297439
No. 4,276,347), thione compounds (for example, JP-A-53-144319, JP-A-53-824).
08, 55-77737, etc.), amine compounds (for example, JP-A-54-100717).
Thiourea derivatives (for example, JP-A-55-2982), imidazoles (JP-A-54-100717), substituted mercaptotetrazole (JP-A-57-2082)
2531) and the like.

For the production of the silver halide emulsion used in the present invention, any known method can be used. That is, a silver salt aqueous solution and a halogen salt aqueous solution are added to a reaction vessel having an aqueous gelatin solution with efficient stirring. As a specific method, P. Glafkides
Written by Chemie et Phisique Photographique (Paul Montel, 1967), Photographic Emulsion C by GFDuffin
hemistry (published by The FocalPress, 1966), VLZelikma
Making and Coating PhotographicEmulsion by n et al
(The Focal Press, 1964) and the like. That is, any of an acidic method, a neutral method, an ammonia method, etc. may be used, and a method of reacting a soluble silver salt and a soluble halide may be any of a one-sided mixing method, a double-mixing method, a combination thereof, and the like. Good. As one type of the double jet method, a method of maintaining a constant pAg in a liquid phase in which silver halide is formed, that is, a so-called controlled double jet method can be used. Also, British Patent No. 153016, JP-B-48-36890 and JP-B-52-16364.
No. 4,242,445, Japanese Patent Application Laid-Open No. 55-158124, and the like, as described in each of the publications, a method in which the addition rate of silver nitrate or an aqueous alkali halide solution is changed according to the grain growth rate. It is preferred that the growth be carried out quickly within a range not exceeding the critical supersaturation using the method of changing the aqueous solution concentration as described.
These methods are preferably used because they do not cause renucleation and the silver halide grains grow uniformly.

Instead of adding a silver salt solution and a halide solution to the reaction vessel, fine particles prepared in advance are added to the reaction vessel to cause nucleation and / or grain growth to obtain silver halide grains. Preferably, a method is used. This technique is disclosed in JP-A-1-183644 and JP-A-1-183645, and U.S. Pat.
8, JP-A-2-44335, JP-A-2-43
534 and JP-A-2-43535. According to this method, the distribution of halogen ions in the emulsion grain crystals can be made completely uniform, and favorable photographic characteristics can be obtained. Further, in the present invention,
Emulsion grains having various structures can be used. So-called core / shell double-structure particles comprising the inside (core) and the outside (shell) of the particles,
For example, a triple structure particle as disclosed in Japanese Patent Application No. 22844 or a multilayer structure particle having a larger structure may be used. When a structure is provided inside the emulsion grains, not only the above-described wrapping structure but also a grain having a so-called junction structure can be produced. These examples are disclosed in JP-A-59-133540.
JP-A-58-108526, European Patent 19
No. 9290A2, JP-B-58-24772, JP-A-59-16254, and the like.
The crystal to be bonded can be formed by bonding to the edge, corner, or face of the host crystal with a composition different from that of the host crystal. Such a junction crystal can be formed even if the host crystal is uniform in halogen composition or has a core-shell structure. In the case of a joint structure, a combination of silver halides is of course possible, but if a silver salt compound having a non-rock salt structure such as silver silver or silver carbonate can be combined with silver halide to form a joint structure, it is used. You may.

In the case of silver iodobromide particles having these structures, for example, in core-shell type particles, even if the silver iodide content in the core portion is high and the silver iodide content in the shell portion is low, Conversely, grains having a low silver iodide content in the core portion and a high silver iodide content in the shell portion may be used. Similarly, particles having a bonding structure may be particles having a high silver iodide content in the host crystal and a relatively low silver iodide content in the bonding crystal, or vice versa. Also,
The boundary portions having different halogen compositions in the grains having these structures may be clear boundaries, or may be unclear boundaries due to the formation of a mixed crystal due to a composition difference. It may have a structural change. The silver halide emulsion used in the present invention is described in EP-0097727B1, EP
-006412B1 A treatment for imparting roundness to particles as disclosed in each specification, or DE-23.
The surface may be modified as disclosed in the specification of JP 0664747 C2 and JP-A-60-221320. As the chemical sensitization in the present invention, chalcogen sensitization such as sulfur sensitization, selenium sensitization, and tellurium sensitization, and noble metal sensitization and reduction sensitization can be used alone or in combination.

In the sulfur sensitization, an unstable sulfur compound is used, and P. Grafkides, Chimie et Physique Photograph
ique (Paul Momtel, 1987, 5th edition), Research
Unstable sulfur compounds described in Disclosure 307, 307105 and the like can be used. Specifically, thiosulfates (eg, hypo), thioureas (eg, diphenylthiourea, triethylthiourea, N-
Ethyl-N ′-(4-methyl-2-thiazolyl) thiourea, carboxymethyltrimethylthiourea), thioamides (eg, thioacetamide), rhodanines (eg, diethyl rhodanine, 5-benzylidene-N-ethyl-) Rhodanine), phosphine sulfides (eg, trimethylphosphine sulfide), thiohydantoins, 4-oxo-oxazolidine-2-thiones, dipolysulfides (eg, dimorpholine disulfide, cystine, hexathiocan-thione), mercapto Known sulfur compounds such as compounds (for example, cysteine), polythionates, elemental sulfur, and active gelatin can also be used.

In the selenium sensitization, an unstable selenium compound is used, and JP-B-43-13489 and JP-B-44-157.
No. 48, JP-A-4-25832, JP-A-4-109240
And labile selenium compounds described in Japanese Patent Application Nos. 3-53693 and 3-82929 can be used. Specifically, colloidal metal selenium, selenoureas (eg, N, N-dimethylselenourea, trifluoromethylcarbonyl-trimethylselenourea, acetyl-trimethylselenourea), selenoamides (eg, selenoacetamide, N, N-diethylphenylselenoamide), phosphine selenides (eg, triphenylphosphine selenide, pentafluorophenyl-triphenylphosphine selenide), selenophosphates (eg, tri-p-tolylselenophosphate) , Tri-n-butylselenophosphate), selenoketones (eg, selenobenzophenone), isoselenocyanates, selenocarboxylic acids,
Selenoesters and diacylselenides may be used. Furthermore, Japanese Patent Publication No. 46-4553 and 52-3
Non-labile selenium compounds described in 4492 publications and the like,
For example, selenous acid, potassium selenocyanide, selenazoles, selenides and the like can be used.

In tellurium sensitization, an unstable tellurium compound is used, and Canadian Patent 800958, British Patent 129
Nos. 5462 and 1396696, Japanese Patent Application No.
333819, 3-53693, 3-1315
Unstable tellurium compounds described in JP-A Nos. 98 and 4-129787 can be used. Specifically, telluroureas (e.g., tetramethyltellurourea, N, N'-dimethylethylenetellurourea, N, N '
-Diphenylethylene tellurourea), phosphine tellurides (eg, butyl-diisopropylphosphine telluride, tributylphosphine telluride, tributoxyphosphine telluride, ethoxy-diphenylphosphine telluride), diacyl (di) telluride (E.g., bis (diphenylcarbamoyl) ditelluride, bis (N-phenyl-N-methylcarbamoyl) ditelluride, bis (N-phenyl-N-methylcarbamoyl) telluride, bis (ethoxycarbonyl) telluride), isotellurocyanates, Telluramides, tellurohydrazides, telluroesters (eg, butylhexyltelluroester), telluroketones (eg, telluroacetophenone), colloidal tellurium, (di) tellurides, and other tellurium compounds Potassium nitrosium telluride, tellurocarbonyl penta isethionate sodium salt) or the like may be used.

Noble metal sensitization is described in P. Grafkide, supra.
s, Chimie et Physique Photographique (Paul Momt
el company, 1987, 5th edition), Research Disclosure 3
Gold, platinum, and the like described in Vol.
Noble metal salts such as palladium and iridium can be used, and gold sensitization is particularly preferable. Specifically, in addition to chloroauric acid, potassium chloroaurate, potassium aurithiocyanate, gold sulfide, and gold selenide, U.S. Patent Nos. 2642361, 5049484, and 50494
The gold compounds described in the specification of No. 85 can also be used. For reduction sensitization, see P. Grafkides, Ch.
imie et Physique Photographique (Paul Momtel,
1987, 5th edition), Research Disclosure 307, 3
Known reducing compounds described in No. 07105 or the like can be used. Specifically, aminoiminomethanesulfinic acid (also called thiourea dioxide), borane compound (for example, dimethylamine borane), hydrazine compound (for example, hydrazine, p-tolylhydrazine), polyamine compound (for example, diethylenetriamine, triethylene Tetramine), stannous chloride, silane compounds,
Reductones (eg, ascorbic acid), sulfites,
An aldehyde compound, hydrogen gas, or the like may be used. The reduction sensitization may be performed in an atmosphere having a high pH or an excess of silver ions (so-called silver ripening).

These chemical sensitizations may be used alone or in combination of two or more. When combined, a combination of chalcogen sensitization and gold sensitization is particularly preferable. Further, reduction sensitization is preferably performed at the time of forming silver halide grains. The amount of the chalcogen sensitizer used in the present invention varies depending on silver halide grains to be used, chemical sensitization conditions, and the like, but is 10 ^-8 to 10 ^-2 mol, preferably 1 to 10 mol per mol of silver halide.
About 0 ^{-7 to} 5 × 10 ^-3 mol is used. The amount of the noble metal sensitizer used in the present invention is 1 to 1 mol of silver halide.
About 0 ^-7 to 10 ^-2 mol is used. The conditions of the chemical sensitization in the present invention are not particularly limited, but the pAg is 6 to 1
1, preferably 7 to 10 and a pH of 4 to 10
Preferably, the temperature is 40 to 95 ° C, and more preferably 4 to 95 ° C.
5-85 ° C is preferred.

[0037]

Example 1 Pure silver bromide tabular grain emulsion Emulsion 1-A (comparative) In a well-stirred reaction vessel, 1.0 liter of water, 3 g of low molecular weight bone gelatin (average molecular weight: 20,000) and 0.5 g of KBr were added. Add and dissolve and stir into the solution maintained at 40 ° C.
10 cc of a 0.5 M silver nitrate solution and 20 c of a 0.3 M KBr solution
c was added over 40 seconds. (Nucleation) Thereafter, 22 cc of a 0.8 M KBr solution was added. One minute after completion of the addition, 350 mmol of 0.2 mmol of the crystal habit controlling agent 1 and a 10% by weight solution of deionized alkali-treated bone gelatin were added, and then the temperature was raised to 75 ° C., followed by aging for 5 minutes. (Aging) Next, a 1000 M silver nitrate solution and a 1.0 M KBr solution were added at an accelerated flow rate of 1000 cc each over 60 minutes.
(The flow rate at the end was 5 times the flow rate at the start.) (Growth) After the addition was completed, the emulsion was cooled to 35 ° C., washed with normal flocculation, and 70 g of lime-processed bone gelatin was added.
After dissolving and adjusting the pAg to 8.7 and the pH to 6.5, the mixture was stored in a cool and dark place. Emulsion 1-B (Invention) Emulsion 1-A was carried out in the same manner as in Emulsion 1-A, except that dodecyl ambered gelatin was added in the same amount as in Emulsion 1-A instead of deionized alkali-treated bone gelatin. Table 1 shows the properties of the obtained tabular grains. Emulsion 1-C (Comparative) Emulsion 1-A was carried out in the same manner as Emulsion 1-A, except that the same amount of trimellitated gelatin was used instead of deionized alkali-treated bone gelatin added during ripening. Table 1 shows the properties of the obtained tabular grains.

[0038]

[Table 1]

As shown in Table 1, the emulsion of the present invention can reduce the coefficient of variation of the equivalent circle diameter of tabular grains without changing the equivalent circle diameter and thickness of the tabular grains.

Example 2 Silver iodobromide tabular grain emulsion Emulsion 2-A (comparative) In the system shown in FIG. 3 of JP-A-2-213837, the mixer shown in FIG. Using a 0.5 cc volume), tabular grains were prepared as follows. This embodiment shows a method in which both nucleation and particle growth are performed in a mixer. In a mixer 7, an aqueous solution of 0.021M silver nitrate 5
00cc, low molecular weight gelatin (average molecular weight 30,000) 0.1
500 cc of a 0.028M KBr aqueous solution containing 0.1% by weight was continuously added for 20 minutes, and the resulting emulsion was continuously placed in a reaction vessel over 20 minutes to obtain a 1,000 cc nuclear emulsion. At that time, the stirring rotation speed of the mixer was 2000 rpm. (Nucleation) After the nucleation is completed, 22 cc of the 0.8 M KBr solution and the crystal habit controlling agent 1 are added to 0.2 ml of the nuclear emulsion while stirring the nuclear emulsion in the reaction vessel well.
300 ml of 10% by weight of trimellitated gelatin containing 2 mmol was added, the temperature was raised to 75 ° C., and the mixture was left for 5 minutes. (Aging) Then, a 0.6M silver nitrate aqueous solution 1000
cc and 1000 cc of a 0.6 M aqueous solution of KBr containing 50 g of low molecular weight gelatin (average molecular weight of 40,000) and 3 mol% of KI were added at a constant flow rate for 56 minutes. The fine grain emulsion produced in the mixer was continuously added to the reaction vessel. At that time, the stirring rotation speed of the mixer was 2000 rpm. At the same time, 1/5
150 cc of a 0 M solution of the crystal habit controlling agent I was continuously added to the reaction vessel at a constant flow rate. The stirring blade of the reaction vessel was rotated at 800 rpm and was well stirred. (Growth) during grain growth, a IrCl ₆ was 8 × 10 ^-8 mol / molAg added doped at the time of the addition of 70% of silver nitrate. Further, a yellow blood salt solution was added to the mixer before the end of the particle growth. The yellow blood salt was doped into the shell portion of the particles at 3% (in terms of the amount of added silver) so as to have a local concentration of 3 × 10 ⁻⁴ mol / mol Ag. After the addition was completed, the emulsion was cooled to 35 ° C., washed with water by a usual flocculation method, and 70 g of lime-processed bone gelatin was added.
After adding and dissolving to adjust the pAg to 8.7 and the pH to 6.5, the mixture was stored in a cool dark place. Table 2 shows the properties of the obtained tabular grains. Emulsion 2-B (invention) Emulsion 2-A was carried out in the same manner as Emulsion 2-A, except that the same amount of dodecyl succinated gelatin was used instead of the trimellitated gelatin added during ripening. Table 2 shows the properties of the obtained tabular grains. Emulsion 2-C (Comparative) Emulsion 2-A was carried out in the same manner as Emulsion 2-A, except that the same amount of amber gelatin was used instead of the trimellitated gelatin added during ripening. Table 2 shows the properties of the obtained tabular grains. Emulsion 2-D (Comparative) Emulsion 2-A was performed in the same manner as Emulsion 2-A, except that the same amount of alkali-treated osseinated gelatin was used instead of the trimellitated gelatin added during ripening. Table 2 shows the properties of the obtained tabular grains.

[0041]

[Table 2]

As shown in Table 2, the emulsion of the present invention can reduce the coefficient of variation of the equivalent circle diameter of tabular grains without changing the equivalent circle diameter and thickness of the tabular grains.

[0043]

According to the present invention, an emulsion composed of tabular grains having a very small thickness and a high aspect ratio can be prepared and the grain size can be monodispersed.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) G03C 1/015 G03C 1/015 1/047 1/047 1/07 1/07

Claims (5)

[Claims] In a photosensitive silver halide emulsion comprising silver halide grains and a dispersion medium, 50% or more of the total projected area of all silver halide grains has an aspect ratio of 3 or more and a thickness of 3 or more.
0.3 μm or less silver halide tabular grains, substituted by at least one aliphatic hydrocarbon having 4 to 16 carbon atoms or at least one aromatic hydrocarbon having an aliphatic hydrocarbon group having 4 to 16 carbon atoms A light-sensitive silver halide emulsion characterized by containing a processed gelatin. 2. Photosensitivity comprising silver halide grains and a dispersion medium.
Silver halide emulsion, the total projection surface of all silver halide grains
50% or more of the product has an aspect ratio of 3 or more and a thickness of 0.3 μm
Hereinafter, a silver halide flat plate whose main surface is a (111) plane
Method for producing a photosensitive silver halide emulsion comprising
The tabular grains have at least one carbon atom of 4 to 1;
6 aliphatic hydrocarbons or at least one carbon number 4
Substituted with an aromatic hydrocarbon having from 16 to 16 aliphatic hydrocarbon groups
In a dispersion medium containing the replaced gelatin, the following general formula (I):
At least one of the compounds represented by (II) or (III)
Photosensitive halogen characterized by being prepared in the presence of a seed
Method for producing silver halide emulsion. Embedded imageWhere R₁Represents an alkyl group, an alkenyl group, or an aralkyl group.
Represents, R_Two, R_Three, R _Four, R_FiveAnd R₆Is water
Represents an atom or a substituent. R_TwoAnd R_Three, R_ThreeAnd R_Four,
R_FourAnd R_Five, R_FiveAnd R₆May be fused. Where R
_Two, R_Three, R_Four, R_FiveAnd R₆At least one of the ants
Represents a hydroxyl group. X^-Represents a counter anion. Embedded imageWhere A₁, A_Two, A_ThreeAnd A_FourCompletes nitrogen-containing heterocycle
Represents a group of non-metallic atoms for
It may be different. B represents a divalent linking group. m is 0
Or represents 1. R₁, R_TwoRepresents an alkyl group.
You. X represents an anion. n represents 0 or 1;
In the case of an inner salt, n is 0. 3. The composition according to claim 1, wherein at least 50% by mole of silver bromide is contained and at least 50% of the total projected area of all grains has an aspect ratio of
2. A silver halide tabular grain having a main surface with a thickness of not less than 8 and a thickness of not more than 0.05 .mu.m being a (111) plane.
3. The method for producing a photosensitive silver halide emulsion of claim 2 or the photosensitive silver halide emulsion of claim 2. 4. A halogen containing at least 50 mol% of silver chloride and at least 50% of the total projected area of all grains having an aspect ratio of 8 or more and a thickness of 0.3 μm or less whose main surface is a (111) plane. 2. A silver halide tabular grain.
3. The method for producing a photosensitive silver halide emulsion of claim 2 or the photosensitive silver halide emulsion of claim 2. 5. A mixer is provided outside a reaction vessel for causing nucleation and / or growth of silver halide grains, and an aqueous solution of a water-soluble silver salt and an aqueous solution of a water-soluble halide are supplied to the mixer. 2. The method according to claim 1, wherein the silver halide grains are mixed to form fine silver halide grains, and the fine grains are immediately supplied to a reaction vessel to cause nucleation and / or growth of the silver halide grains in the reaction vessel. A method for producing a photosensitive silver halide emulsion or the photosensitive silver halide emulsion according to claim 2.