JPH10307356A - Silver halide emulsion and silver halide photographic sensitive material using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the flat silver halide grain emulsion superior in monodispersion performance and to provide the silver halide photographic sensitive material enhanced in photographic characteristics, such as graininess and sensitivity and sharpness, by using this emulsion formed in the presence of polymers having at least one unit selected from respective specified repeating units. SOLUTION: The silver halide emulsion has grains grown in the presence of the polymer comprising repeating units represented by one of formulae I and II in which each of L1 -L4 is, independently, a divalent bonding group; each of X1 and X2 is, independently, a trivalent bonding group; each of R1 , R2 , R5 , and R6 is a 1-4C alkylene group; each of n, n', m, and m' is an integer of 4-200; and each of R3 , R4 , R7 , and R8 is an H atom or a 1-12C alkyl or alkenyl or aryl or aralkyl group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silver halide emulsion and a silver halide photographic material using the same, and more particularly to a monodisperse tabular silver halide formed in the presence of a novel polymer. The present invention relates to a grain emulsion and a silver halide photographic material which is excellent in graininess, sensitivity and sharpness by using the emulsion.

[0002]

2. Description of the Related Art Silver halide grains containing two or more twin planes in parallel have a tabular form (hereinafter, referred to as "tabular grains"). The tabular grains have the following photographic properties.

1) The ratio of surface area to volume (hereinafter referred to as specific surface area) is large, and a large amount of sensitizing dye can be adsorbed on the surface. As a result, the color sensitization sensitivity is relatively high.

2) When an emulsion containing tabular grains is coated and dried, the grains are arranged parallel to the surface of the support.
Light scattering by particles can be reduced, and sharpness and resolution can be improved. In addition, the thickness of the coating layer can be reduced by this arrangement, and the sharpness can be improved.

3) Since the specific surface area is large, the development can be accelerated.

1) High covering power enables silver saving.

Because of these many advantages, they have been used in high-sensitivity commercial photographic materials.

JP-A-58-113926 and JP-A-58-1
Nos. 13927 and 58-113928 disclose emulsion grains having an aspect ratio of 8 or more. Here, the aspect ratio is indicated by a ratio of a diameter to a thickness of a tabular grain. Further, the diameter of a particle refers to the diameter of a circle having an area equal to the projected area of the particle. The thickness is indicated by the distance between two parallel main surfaces constituting the tabular grains.

However, as seen in the examples of the above-mentioned patents, tabular grains prepared by a known preparation method have poor monodispersibility. This means that, in addition to the tabular grains having a wide distribution of the projected area diameter of the tabular grains, rod-like grains, tetrapot-like grains, single twin grains and grains having non-parallel twin planes are mixed.

For this reason, it is not possible to expect a high contrast (so-called high gamma) of the characteristic curve. When an emulsion in which large grains and small grains are mixed is chemically sensitized, the optimum conditions of the chemical sensitization are different between the large grains and the small grains. Therefore, it is difficult to perform optimal chemical sensitization for both. Compared to an emulsion coating layer in which large grains and small grains are mixed, a multilayer system in which monodisperse large grains are applied to the upper layer and monodisperse small grains are applied to the lower layer is preferred. However, this method has a high sensitivity in terms of light use efficiency, but has drawbacks such as the inability to sufficiently utilize this layering effect.

Therefore, various attempts have been made to monodisperse tabular grains, and several patents have been disclosed. The monodisperse tabular grains disclosed in JP-A-52-153428 are limited in that AgI crystals are used as nuclei, and the resulting grain shape has a small tabular grain ratio. JP-A-55-142329 discloses growth conditions for monodispersion of tabular grains, but the resulting grains have a low ratio of tabular grains. JP-A-51-39027 discloses a method in which monodisperse twin grains are grown by adding a silver halide solvent after nucleation and then grown. The resulting grains have a low tabular grain ratio and a low aspect ratio. The ratio is also low. As a particle forming process, there is JP-A-61-112142 as a monodisperse twin particle patent similar to this patent. In this patent, since spherical grains are used as seed crystals, only tabular grain emulsions having an aspect ratio of 2.2 or less and a low tabular grain ratio can be obtained. French Patent No. 2,534,
The monodisperse tabular grains described in No. 036 are formed by a method of ripening without using a silver halide solvent after nucleation, and the coefficient of variation of the equivalent circle diameter (standard equivalent circle diameter) of the resulting tabular grains is obtained. The numerical value obtained by dividing the deviation by the average equivalent circle diameter by 100) is 15%. Calculated from the grain photographs described in the examples of this patent, the projected area of triangular tabular grains is 50% or more. This triangular tabular grain is described in J. E. FIG. Maskasky, J. et al. Imaging
Sci. According to pp. 15-26, 1987, it is a grain having three twin planes parallel to the main surface.

JP-A-63-11928 and 63-15
No. 1618 and JP-A-2-838 disclose monodispersed tabular grains containing hexagonal tabular grains. The hexagonal tabular grains are different from the above triangular tabular grains and are tabular grains having two parallel twin planes. JP-A-2-838
In Example 1, the monodisperse tabular grains in which the ratio of the tabular grains having two parallel twin planes to the total projected area is 99.7% and the variation coefficient of the circle equivalent diameter is 10.1% are described. There is a description.

US Pat. Nos. 5,147,771 and 5,147,771.
Nos. 171,659, 5,147,772, 5,1
No. 47,773 discloses a production method for obtaining monodisperse tabular grains by allowing a polyalkylene oxide block copolymer to be present during nucleation. European Patent No. 514742A discloses a monodisperse tabular grain emulsion having a coefficient of variation of 10% or less. In this patent,
In all of the examples, the above-mentioned polyalkylene oxide block copolymers are used.

However, when tabular grains are formed in accordance with this embodiment, monodisperse grains having a circle-equivalent diameter are formed, but there is no specific description regarding the thickness variation coefficient.
In addition, it can be seen that the tabular grains have irregular shapes that differ randomly from the lengths of the six sides. When the monodisperse tabular emulsion thus obtained was used in a silver halide photographic light-sensitive material, the graininess and sensitivity were improved, but this was not sufficient, and the tabular emulsion was not sharp. Are not always sufficient, and further improvement has been desired.

[0015]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a tabular silver halide grain emulsion having excellent monodispersity, and by using the emulsion, to obtain a graininess, sensitivity and sharpness photograph. An object of the present invention is to provide a silver halide photographic light-sensitive material having excellent characteristics.

[0016]

The above objects of the present invention have been attained by the following constitutions.

(1) The fact that particles were formed in the presence of a polymer having at least one unit selected from the repeating unit represented by the following general formula (1) and the repeating unit represented by the following general formula (2): A characteristic silver halide emulsion.

[0018]

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[Wherein L ₁ , L ₂ , L ₃ and L ₄ each represent a divalent linking group which may be the same or different;
₁ and X ₂ each represent a trivalent linking group which may be the same or different, and R ₁ , R ₂ , R ₅ and R ₆ each represent an alkylene group having 1 to 4 carbon atoms, and n, n ′, m and m ′ each represent an integer of 4 to 200, and R ₃ , R ₄ , R
₇ and R ₈ are each a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an aralkyl group having 1 to 12 carbon atoms,
Represents —CO—R ₁₀ or —SO ₂ —R ₁₁ , wherein R ₁₀ and R ₁₁ each represent an alkyl group, an alkenyl group, an aryl group or an aralkyl group having 1 to 12 carbon atoms. (2) The silver halide emulsion according to item (1), wherein the silver halide emulsion contains silver halide tabular grains having an aspect ratio of 2 or more.

(3) The silver halide emulsion according to the above (2), wherein the coefficient of variation of the equivalent circle diameter of the silver halide tabular grains is 20% or less.

(4) The variation coefficient of the thickness of the silver halide tabular grains is 30% or less (2).
Or the silver halide emulsion according to any one of the above (3).

(5) In a silver halide photographic material having at least one light-sensitive silver halide emulsion layer on a support, at least one of the silver halide emulsion layers is any one of 1 to 4. 6. A silver halide photographic material comprising the silver halide emulsion described in 1. above.

Hereinafter, the present invention will be described in detail.

In the present invention, the obtained silver halide emulsion is a silver halide emulsion comprising a dispersion medium and silver halide grains, and the total projected area of the silver halide grains is 9%.
0% or more is occupied by tabular grains having two twin planes parallel to the main plane, the tabular grains have a hexagonal shape, and the size distribution of the tabular grains is monodisperse. It is a feature. The hexagonal tabular grains referred to in the present invention are those in which the ratio of the length of two adjacent sides of the six sides forming the hexagon is 2 or less, and the length of any two adjacent sides of the six sides. The tabular grains are such that the deviation from the ratio of the other two sides is 10% or less.

The monodisperse hexagonal tabular grains of the present invention are characterized in that the circle-equivalent diameter is monodisperse, and the monodispersity here is represented by a coefficient of variation. The monodispersity of the tabular grains of the present invention is preferably 20% or less in terms of variation coefficient from the viewpoint of sharpness, and particularly preferably 15% or less. The monodisperse hexagonal tabular grains of the present invention are characterized in that the thickness is also monodisperse, and the monodispersity referred to here is similarly represented by a coefficient of variation. The monodispersity of the thickness of the present invention is preferably 30% or less in terms of variation coefficient in terms of sharpness, more preferably 25% or less, and particularly preferably 20% or less. The average aspect ratio of the monodisperse hexagonal tabular grains of the present invention is preferably 2 or more from the viewpoint of sensitivity. Here, the average aspect ratio means an average value of aspect ratios of all tabular grains having a diameter of 0.2 μm or more present in the emulsion.

The polymer of the present invention having at least one unit selected from the repeating units represented by the general formula (1) and the repeating units represented by the general formula (2)
It is also referred to as the polymer of the present invention or the phosphazene polymer of the present invention. ) Will be described.

In the general formulas (1) and (2), the divalent linking groups represented by L ₁ , L ₂ , L ₃ and L ₄ include —O—, —S— and —N (R ₉ ) — or an alkylene group having 1 to 12 carbon atoms. R ₉ represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms or an alkenyl group. The alkylene group, alkyl group and alkenyl group may have a substituent, and examples of the substituent include a halogen atom, a cyano group, a sulfo group, a hydroxy group, a carboxy group, an alkyl group, an aryl group, and an aralkyl group. An acyloxy group, an acylamino group, an amino group, a sulfonamide group, an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a carbamoyl group, a sulfamoyl group, an alkoxycarbonyl group, an aryloxycarbonyl group, an alkylsulfonyl group, an arylsulfonyl group, Examples thereof include an alkoxysulfonyl group, an aryloxysulfonyl group, a carbamoylamino group, a sulfamoylamino group, a carbamoyloxy group, an alkoxycarbonylamino group, and an aryloxycarbonylamino group. And 2 represented by L ₁ , L ₂ , L ₃ and L ₄
As the valent linking group, -O-, -S-, -N (R ₉ )-
R ₉ is preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms which may have a substituent.

As the trivalent linking group represented by X ₁ and X ₂ , a linking group represented by the following general formula (3) is preferable.

[0029]

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Wherein A is -L ₇ -C (= O)-, -L
—SO ₂ —, an alkylene group having 1 to 6 carbon atoms, 6 to 6 carbon atoms
10 represents an arylene group or an aralkylene group. B
-C (R ₃₎ is <, - N <, - O -CH <, or

[0031]

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Represents the following. L ₅ , L ₆ and L ₇ may be the same or different and represent a divalent linking group;
To 14 alkylene groups, arylene groups, or aralkylene groups are preferred. p, q, r, s, and t are each independently 0 or 1. Specific examples of the linking group represented by the general formula (3) include, for example,

[0033]

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[0034]

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And the like. These groups have 1 to 1 carbon atoms.
Twelve are preferred, and these groups may have a substituent. Examples of the substituent include the same substituents as those described for L _{1 to} L ₄ .

The alkylene group having 1 to 4 carbon atoms represented by R ₁ , R ₂ , R ₅ and R ₆ includes, for example, ethylene group,
—CH ₂ —CH (CH ₃ ) — and the like are preferred.

A hydrogen atom represented by R ₃ , R ₄ , R ₇ and R ₈ , an alkyl group, an alkenyl group, an aryl group, an aralkyl group, —CO—R ₁₀ or —SO ₂ having 1 to 12 carbon atoms
In -R _11, from 1 to 12 carbon atoms, an alkyl group, an alkenyl group, an aryl group, an aralkyl group, -CO-R ₁₀ or -SO ₂ -R ₁₁ may have a substituent, the substituent Examples thereof include the same substituents as those described for L _{1 to} L ₄ . R ₁₀ and R ₁₁ each have 1 to 12 carbon atoms
Represents an alkyl group, an alkenyl group, an aryl group or an aralkyl group, and these groups may have a substituent. Examples of the substituent include the same substituents as those described for L _{1 to} L _4. No.

The group represented by R ₃ , R ₄ , R ₇ and R ₈ is preferably an alkyl group, an alkenyl group, an aryl group which may have a substituent having 1 to 8 carbon atoms, or —CO 2
—R ₁₀ (R ₁₀ is an alkyl group or an aryl group which may have a substituent having 1 to 8 carbon atoms), for example, a methyl group, an ethyl group, a hexyl group, and —CH ₂ CF
_Three groups, an allyl group, a phenyl group, an acetyl group, a propionyl group, and the like.

N, n ', m and m' each represent 4 to 2
It represents an integer of 00, preferably an integer of 10 to 100.

In the phosphazene polymer of the present invention, as the remaining repeating units, for example, at least one selected from the repeating units represented by the following general formula (4) and the repeating units represented by the following general formula (5) Units can be mentioned.

[0041]

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[Wherein, D ₁ , D ₂ , D ₃ and D ₄ have the same meanings as L ₁ , L ₂ , L ₃ and L _{4 in} the general formulas (1) and (2). K ₁ , K ₂ , K ₃ and K ₄ may be the same or different, and each has 1 to 12 carbon atoms such as an alkyl group, an alkenyl group, an aryl group, an aralkyl group, and-(K ₅ -O) _C -K.
₆ or

[0043]

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K ₅ , K ₇ and K ₈ may be the same or different and each represents a lower alkylene group; K ₆ , K ₉ and K ₁₀ may be the same or different and may be a hydrogen atom , alkyl group, alkenyl group, aryl group, aralkyl group, -CO-K ₁₁ -, or -SO ₂
-K ₁₁ - represents a. K ₁₁ represents an alkyl group, an alkenyl group, an aryl group, or an aralkyl group. Y ₁ has the same meaning as X ₁ and X _{2 in} formulas (1) and (2). c, w,
w 'represents an integer of 1 to 200. In the general formulas (4) and (5), the alkyl group, the alkenyl group, the aryl group, and the aralkyl group may be substituted, and examples of the substituent include the general formula (1)
Substituents exemplified for L ₁ , L ₂ , L ₃ and L ₄ in (2) can be mentioned.

The groups represented by K ₁ , K ₂ , K ₃ and K ₄ are preferably an alkyl group having 1 to 6 carbon atoms, an alkenyl group, and-(K ₅ -O) _{6 C-} K groups, or

[0046]

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The group is, for example,

[0048]

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And the like. Here, o, w and w 'are each independently an integer of 4 to 200, preferably 1
It is an integer of 0 to 100.

The phosphazene polymer of the present invention has a general formula (1) in which at least one unit selected from a repeating unit represented by the general formula (1) and a repeating unit represented by the general formula (2) is 10 to 100. Mol%, preferably 20 to 75 mol% or more. In this case, the compound may have a plurality of at least one unit selected from the repeating unit represented by the general formula (1) and the repeating unit represented by the general formula (2), or may be represented by the general formula (4) It may have a plurality of repeating units and at least one unit selected from the repeating units represented by the general formula (5).

The weight average molecular weight of the phosphazene polymer of the present invention is preferably from 10,000 to 5,000,000, more preferably from 100,000 to 3,000,000.
0.

Since the phosphazene polymer of the present invention is used for preparing an emulsion in an aqueous medium, it is preferable to introduce a dissociable group into the polymer to enhance the solubility of the polymer in the aqueous medium. Suitable dissociable groups include a carboxyl group, a sulfonic acid group, a sulfuric acid monoester group, -OPO
An anionic group such as (OH) ₂ , a sulfinic acid group, or a salt thereof (eg, an alkali metal salt such as Na or K, or an ammonium salt such as trimethylamine), or a cationic group such as a quaternary ammonium salt. Although an anionic group is preferable, a carboxyl group or a salt thereof is particularly preferable.

The following are typical examples of the phosphazene polymer of the present invention, but the present invention is not limited thereto.
In addition, n represents that it polymerizes in a repeating unit, x,
y represents a copolymer molar ratio.

[0054]

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[0055]

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[0056]

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[0057]

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[0058]

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Next, typical examples of the synthesis of the phosphazene polymer of the present invention are shown below.

Synthesis Example 1 Synthesis of exemplified phosphazene polymer P-2 (compound containing 100% of a repeating unit represented by P-2) (1) Synthesis of polydichlorophosphazene (D-1) (NPCl ₂ ) ₃ 100 g (0.29 mol) into a Pyrex tube, and evacuate the inside of the tube (10 ^-2 torr).
After r), the tube was sealed. This tube
The mixture was placed in an electric oven at 50 ° C. and reacted for 220 hours.

After the reaction, the contents were taken out and sublimated (at 50 ° C.).
/ 24 hours) to obtain 85 g (yield: 85%) of the target product D-1 by removing unreacted raw materials.

(2) HO-CH <(-CH _2- (OCH _{2
CH 2) 2 -OCH 3) 2} , synthetic diethylene glycol monomethyl ether 300g of (D-2)
(2.5mol) 12% of 60% oily sodium hydride
(0.3 mol), and 23 g (0.25 mol) of epichlorohydrin was added dropwise at 60 ° C. with stirring over 30 minutes. Then, after reacting for 8 hours, dilute hydrochloric acid was added to the system to add p.
After adjusting to H ≒ 3, the desired product was extracted with 1.2 l of chloroform. The organic layer was washed with water, dried over anhydrous magnesium sulfate, and chloroform was distilled off under reduced pressure. The residue was distilled under reduced pressure to give 53.2 g of the target product D-2 as a colorless and transparent oil (yield: 60).
%) Obtained (b. P 170-182 ° C / 2 mmHg).

The chemical structure was confirmed by NMR, IR and elemental analysis.

(3) Synthesis of phosphazene polymer P-2 50 g (0.19 mol) of compound (D-2) was dissolved in 250 ml of tetrahydrofuran, and 5 g (0.13 mol) of 60% oily sodium hydride was added thereto. Under stirring, 100 ml of a tetrahydrofuran solution of 5 g (0.043 mol) of the compound (D-1) was added dropwise over 2 hours. To this is added n-tetrabutylammonium bromide 0.1.
After adding 1 g and stirring at room temperature for 48 hours, the mixture was heated and refluxed for 2 hours.

After completion of the reaction, the system was neutralized by adding dilute hydrochloric acid.
Dialysis was performed for 72 hours against ion exchanged water to remove low molecular weight components. The obtained polymer was dissolved in 250 ml of acetone, and 1 l of hexane was added for reprecipitation purification. This operation was repeated twice to obtain 5.5 g of the objective phosphazene polymer P-2 as a yellowish-white viscous solid (Mw (average) @ 650,
000).

The chemical structure was confirmed by NMR, IR and elemental analysis.

Next, a method for producing the silver halide emulsion of the present invention will be described. The silver halide emulsion of the present invention can be produced in the process of nucleation → ripening → growth. The phosphazene polymer of the present invention (hereinafter, also referred to as the polymer of the present invention)
May be present at any point during grain formation, but it is desirable to exist at least before growth, preferably before ripening, and more preferably before nucleation.

The nucleation, ripening and growth steps of the production according to the present invention will be described below.

1. Nucleation The nucleation of tabular grains is generally carried out by adding a silver salt aqueous solution and an alkali halide aqueous solution to a reaction vessel holding an aqueous solution of a protective colloid, or by a double jet method or a protective colloid solution containing an alkali halide. A single jet method in which an aqueous silver salt solution is added is used. In addition, a method of adding an aqueous solution of an alkali halide to a protective colloid solution containing a silver salt, if necessary, can also be used. Further, if necessary, a protective colloid solution, a silver salt solution and an aqueous alkali halide solution are added to a mixer disclosed in JP-A-2-44335, and the mixture is immediately transferred to a reaction vessel to form nuclei of tabular grains. Can also be performed. Also, as disclosed in U.S. Pat. No. 5,104,786, nucleation can be carried out by passing an aqueous solution containing an alkali halide and a protective colloid solution through a pipe and adding an aqueous silver salt solution thereto. it can. For the nucleation, it is preferable that the protective colloid is used as a dispersion medium and the dispersion medium is formed under the condition of pBr of 1 to 4. Protective colloids include gelatin and protective colloid polymers. As the kind of gelatin, alkali-treated gelatin is usually used, but low molecular weight gelatin (molecular weight: 3000 to 40,000) may be used, and oxidized gelatin is preferable. The following are suitable as protective colloids.

(1) Polyvinylpyrrolidone Homopolymer of vinylpyrrolidone, French Patent 2,0
A copolymer of acrolein and pyrrolidone disclosed in U.S. Pat.

(2) Polyvinyl alcohol Homopolymer of vinyl alcohol, US Pat.
No. 0,741, the organic acid monoester of polyvinyl alcohol disclosed in U.S. Pat. No. 3,236,653, and the maleic ester shown in U.S. Pat. No. 3,236,653;
And a copolymer of polyvinyl alcohol and polyvinyl pyrrolidone.

(3) Polymer having a thioether group US Pat. Nos. 3,615,624 and 3,860,428
No. 3,706,564, having a thioether group.

(4) Polyvinylimidazole homopolymer of polyvinylimidazole, copolymer of polyvinylimidazole and polyvinylamide,
Ternary copolymers of acrylamide, acrylic acid and vinylimidazole described in JP-A-3-7561 and German Patents 2,012,095 and 2,012,970.

(5) Polyethyleneimine (6) Acetal polymer Water-soluble polyvinyl acetal shown in US Pat. No. 2,358,836, polyvinyl acetal having a carboxyl group shown in US Pat. No. 3,003,879, UK Polymers disclosed in Japanese Patent No. 771,155.

(7) Amino polymer US Pat. Nos. 3,345,346 and 3,706,504
No. 4,350,759, West German Patent 2,13
No. 8,872, U.S. Pat.
No. 413,125; U.S. Pat. No. 3,425,836;
No. 1,818, a polymer having an amino group and a carboxyl group, and a polymer shown in U.S. Pat. No. 3,832,185.

(8) Polyacrylamide Polymer Homopolymer of acrylic amide, US Pat. No. 2,54
No. 1,474, a copolymer of polyacrylamide by imidization with polyacrylamide, a copolymer of acrylamide and methacrylamide shown in West German Patent 1,202,132, U.S. Pat.
No. 207, a partially aminated acrylamide polymer, a substituted amide polymer disclosed in JP-B-45-14031, U.S. Pat. Nos. 3,713,834 and 3,746,548, and British Patent 788,343. Acrylic amide polymer.

(9) Polymer having hydroxyquinoline US Pat. Nos. 4,030,929 and 4,152,161
The polymer having humanoxyquinoline shown in the above item.

(10) Others A vinyl polymer having an azaindene group described in JP-A-59-8604, a polyalkylene oxide derivative described in US Pat. No. 2,976,150, US Pat.
No. 022,623, polyvinylamine imide polymer, U.S. Pat.
No. 9,688, U.S. Pat.
No. 4,456, No. 3,520,857, a vinyl polymer having an imidazole group, Japanese Patent Publication No. 60-658, a vinyl polymer having a triazole group, Hie Photography 45, 43
Water-soluble polyalkyleneaminotriazoles shown on page (1950). The concentration of the dispersion medium is preferably 10% by weight or less, more preferably 1% by weight or less. The temperature at the time of nucleation is preferably 5 to 60 ° C.
When producing fine tabular grains of m or less, the temperature is preferably 5 to 48 ° C. The pH of the dispersion medium is 8 or less, preferably 6 or less. As the composition of the alkali halide solution to be added,
Br ^- for I ^- content is solid solubility limit of AgBrI generating less, preferably 10 mol% or less. The phosphazene polymer of the present invention is 0.1 to 50 times, preferably 0.1 to 30 times by weight the silver nitrate for nucleation.
It can be used at times or less.

2. Aging 1. In the nucleation in (1), fine particles other than tabular grains (particularly, octahedral and single twin grains) are formed. Prior to the growth process described below, it is necessary to eliminate grains other than tabular grains to obtain nuclei having a shape to be tabular grains and good monodispersity. To make this possible, it is well known to carry out Ostwald ripening following nucleation. Immediately after the nucleation, pBr is adjusted, and the temperature is increased to ripen until the hexagonal tabular grain ratio becomes the highest. At this time, the protective colloid concentration is adjusted. The concentration of the protective colloid is preferably from 1 to 10% by weight. The protective colloid used at this time is suitably gelatin and a protective colloid polymer. Gelatin is usually alkali-treated gelatin,
Oxidized gelatin may be used. The protective colloid polymer comprises: What is described in is good. The aging temperature is 40 ~
80 ° C., preferably 50-80 ° C., pBr is 1.
2 to 3.0. At this time, a silver halide solvent may be added in order to quickly eliminate grains other than tabular grains. In this case, the concentration of the silver halide solvent is preferably 0.3 mol / liter or less,
ol / liter or less is more preferable. When used as an emulsion for direct reversal, a silver halide solvent such as a thioether compound used on a neutral or acidic side is preferable as a silver halide solvent than NH ₃ used on an alkaline side. The ripening is carried out in this manner to obtain almost 100% tabular grains only. After ripening, if the silver halide solvent is unnecessary in the next growth process, the silver halide solvent is removed as follows.

In the case of an alkaline silver halide solvent such as NH ₃ , an acid having a large solubility product with Ag ⁺ such as NHO ₃ is added to nullify the solvent.

In the case of a thioether-based silver halide solvent, as described in JP-A-60-136736, H _{2 is used.}
An oxidizing agent such as O ₂ is added to nullify.

3. The pBr during the crystal growth period following the ripening process is preferably maintained at 1.4 to 3.5. A during the crystal growth period
It is preferable that the addition rate of g ⁺ and the halogen ion is set to 20 to 100%, preferably 30 to 100% of the crystal critical growth rate. in this case,
The rate of addition of silver ions and halogen ions is increased along with the crystal growth.
890, 52-16264, the addition rate of the aqueous solution of silver salt and halogen salt may be increased,
The concentration of the aqueous solution may be increased. During the growing period, the iodine content of AgX deposited on the nucleus is preferably from 0 mol% to the solid solution limit concentration.

The silver halide in the present invention is, for example, silver bromide, silver chlorobromide or silver chloroiodobromide having a silver chloride content of 30 mol% or less. One or more silver halide emulsions of the present invention can be provided on a support together with other emulsions, if necessary. Further, the support can be provided not only on one side but also on both sides. Further, they can be overlaid as emulsions having different color sensitivity. The silver halide emulsion of the present invention is a black-and-white silver halide photographic material (for example, X
Ray-sensitive material, squirrel-type material, negative film for black and white photography, etc.)
And color photographic materials (eg, color negative film,
Color reversal film, color paper, etc.). Further, it can be used as a light-sensitive material for diffusion transfer (for example, a color sales transfer element, a silver salt diffusion transfer element), a heat-developable light-sensitive material (black and white, color) and the like.

Various techniques and inorganic and organic materials which can be used for the silver halide photographic emulsion of the present invention and the silver halide photographic light-sensitive material using the same are generally described in Research Disclosure No. 308119 (1
989) can be used.

The thus obtained tabular silver halide emulsion of the present invention has a uniform grain shape.

The projected area diameter is monodisperse.

The particle thickness is uniform.

The chemical sensitization can be optimally set for each grain, and large grains, medium grains and small grains can be used for the high sensitivity layer, the middle sensitivity layer and the low sensitivity layer, respectively. When the layers are coated in such a manner, a silver halide emulsion for photosensitive can be provided which can sufficiently exhibit the layering effect and has excellent characteristics in sensitivity, granularity, sharpness, and sharpness. Hereinafter, the present invention will be further described with reference to examples.

[0089]

EXAMPLES The present invention will be described below in more detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1 (Preparation of emulsion) Oxidized gelatin 0.41 was placed in a reaction vessel.
g, 4N nitric acid (4.2 ml), KBr (0.73 g), and 1 liter of an aqueous solution containing 3.5 g of the polymer P-3 of the present invention, and stirred at 45 ° C. 0.37 g of Ag was added to this solution.
2.75 ml of an aqueous solution containing NO ₃ and 0.27 g of KBr
Was added over 1 minute while maintaining the temperature by a double jet method. After one minute, KBr2.
19.2 ml of an aqueous solution containing 29 g are added, the temperature is raised to 60 ° C. over 9 minutes and 3.37 g of (NH ₄ ) ₂ SO ₄
And a mixed solution of 2.5N NaOH solution and 26.7 ml, and stirred for 9 minutes. Further, an aqueous solution 9 containing 16.7 g of oxidized gelatin and 10.8 ml of 4N nitric acid.
4.2 ml was added over 2 minutes. Then 1.02g
7.5 ml of an aqueous solution containing AgNO ₃ and 0.79 g of K
8.3 ml of an aqueous solution containing Br was added at a constant rate over 5 minutes. Thereafter, an aqueous solution 474.7 ml containing 129 g of AgNO ₃ and an aqueous solution 47 containing 95 g of KBr
4.7 ml were added simultaneously from the initial flow rates of 1.5 ml / min and 1.62 ml / min at constant flow rate acceleration over 64 minutes.

Next, an aqueous solution 290 containing 2.9 g of KI
ml was added alone over 2 minutes. After 2 minutes, 68.
253.3 ml of an aqueous solution containing 8 g of AgNO ₃ and 5
252 ml of an aqueous solution containing 0.3 g of KBr were simultaneously added at a constant flow rate over 19 minutes.

Thereafter, desalting was carried out by a conventional flocculation method, and at 40 ° C., pH = 6.5 and pAg = 8.5.
After the preparation, the plate was optimally chemically sensitized with sodium thiosulfate, chloroauric acid and potassium thiocyanate at 65 ° C. in the presence of a sensitizing dye (S-6 and S-7 described below). AgBrI emulsion-1 (AgI content = 1.5 mol%) was obtained. The average projected diameter of the obtained particles is 2.0 μ
m, the average grain thickness is 0.132 μm, the projected area diameter is a circle equivalent diameter of 99% of the projected area of all grains having a diameter of 0.2 μm or more, the average aspect ratio is 15.2, and the variation coefficient of the grain diameter is It was 4.7%.

Next, in the production method of Emulsion-1, polymers P-2 and P-2 of the present invention were used instead of polymer P-3 of the present invention.
-7 or P-14 each in 3 g, or EP 5
Compound P used in Example 1 of No. 14,742A
0.13 g of LURONIC TM31R1 or the compound P-3 (4,4'-diphenylmethane diisocyanate / 2,2-bis (hydroxymethyl) propionate / PEG used in Example 1 of JP-A-7-72572) (Mw = 600) / PPG (Mw = 70
0) (41.4 / 15.5 / 19.9 / 32.2; 50)
Emulsions-2 to 4 of the present invention and Comparative Emulsions-A and B, respectively, were prepared in exactly the same manner as Emulsion-1, except that 3 g each of (/ 30/10/10)) was used.

Table 1 shows the characteristics of the emulsion grains obtained as described above.

[0095]

[Table 1]

(Preparation of Coated Sample) Dodecylbenzenesulfonate as a coating aid, p-vinylbenzenesulfonate as a thickener, and vinylsulfone-based hardener as each of the emulsions obtained as described above. An emulsion coating solution was prepared by adding the compound and a polyethylene oxide compound as a photographic property improving agent. Subsequently, these coating solutions were separately coated uniformly on a subbed polyester base, and a surface protective layer mainly composed of an aqueous gelatin solution was coated thereon, to prepare emulsions 1 to 4 and emulsion-A, Application samples 101 to 106 having B were produced. At this time,
The coated silver amount of each of Samples 101 to 106 was 4.0 g.
/ M ² , the amount of gelatin applied to the protective layer was 1.3 g / m ² , and the amount of gelatin applied to the emulsion layer was 2.7 g / m ² .

The following experiment was conducted in order to evaluate the coated product thus obtained.

First, the sample pieces of the coated samples 101 to 106 were subjected to wedge exposure with an exposure amount of 10 CMS for an exposure time of 1/100 second, developed with a processing solution having the following composition at 20 ° C. for 4 minutes, and then fixed and washed with water. After drying, sensitometry was performed, and the sensitivity was determined by the reciprocal of the exposure amount giving a density of fog + 0.1.

Next, two sets of test specimens of the coated samples 101 to 106 were prepared and subjected to wedge exposure at 1/100 ″, and one set was stored at 45 ° C. and 65% RH for 3 days. One set was stored in a freezer and used as a control, subjected to development processing in the same manner as above, and evaluated for sharpness.

The sharpness is based on the MTF (Modulation Transfer Function) method.
The details are described in “Photochemistry” (Photographic Industry Publishing Company, Akira Sasai), pp. 430-437. The MTF chart is exposed and developed with white light, and the MTF value at 40 cycles / mm is shown in the table. Was.

Table 2 shows the results.

[0102]

[Table 2]

Treatment liquid 1-phenyl-3-pyrazolidone 0.5 g vitroquinone 10 g ethylenediaminetetraacetic acid disodium 2 g potassium sulfite 60 g boric acid 4 g potassium carbonate 20 g sodium bromide 5 g diethylene glycol 20 g adjusted to pH 10.0 with sodium hydroxide Water In addition, it is clear from the results in Table 2 that the tabular grains prepared using the phosphazene polymer of the present invention have sensitivity equal to or higher than that of the comparative emulsion and are superior in sharpness.

The same effect was obtained when the silver halide emulsion of the present invention was applied to a multilayer photographic material.

[0105]

According to the present invention, there is provided a tabular silver halide grain emulsion excellent in monodispersity, and by using the emulsion, a silver halide photograph excellent in photographic characteristics of graininess, sensitivity and sharpness is obtained. A photosensitive material could be provided.

Claims (5)

[Claims] 1. A polymer having at least one unit selected from a repeating unit represented by the following general formula (1) and a repeating unit represented by the following general formula (2): Silver halide emulsion. Embedded image [Wherein, L ₁ , L ₂ , L ₃ and L ₄ each represent a divalent linking group which may be the same or different, and X ₁ and X ₂ each represent a trivalent link which may be the same or different. represents a _{group, R 1, R 2, R} 5 and R ₆ each represent an alkylene group having 1 to 4 carbon atoms, n, n ', m and m' each represent an integer of 4 to 200, R _3, R _4, R ₇ and R ₈ are each a hydrogen atom, having 1 to 12 carbon atoms, an alkyl group, an alkenyl group, an aryl group, an aralkyl group, -CO-R ₁₀
Or an -SO ₂ -R _11, representing 1 to 12 carbon atoms and R ₁₀ and R ₁₁ are each an alkyl group, an alkenyl group, an aryl group or an aralkyl group. ] 2. The silver halide emulsion according to claim 1, wherein the silver halide emulsion contains silver halide tabular grains having an aspect ratio of 2 or more. 3. The silver halide tabular grain according to claim 2, wherein the coefficient of variation of the equivalent circle diameter is 20% or less.
The silver halide emulsion as described above. 4. The silver halide emulsion according to claim 2, wherein the coefficient of variation of the thickness of the silver halide tabular grains is 30% or less. 5. A silver halide photographic material having at least one light-sensitive silver halide emulsion layer on a support, wherein at least one of said silver halide emulsion layers is in any one of claims 1 to 4. 13. A silver halide photographic light-sensitive material, comprising the silver halide emulsion described in item 9.