JPH0968770A - Silver halide photographic emulsion and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a silver halide photographic emulsion with which an image with low fog and high sensitivity can be obtd. SOLUTION: This silver halide photographic emulsion is produced by using a sensitizer expressed by [N(R1 )(R2 )][N(R3 )(R4 )]>C=X and thiosulfate in a chemical ageing process. During chemical ageing and before the reaction of the thiosulfate is substantially completed, the sensitizer expressed by formula is added. In formula, X is S, Se or Te, R1 , R2 , R3 , R4 are hydrogen atoms, amidino groups, alkyl groups, aryl groups, or heterocyclic residues, and R1 , R2 , R3 , R4 may be same or different. Or, the sensitizer expressed by formula and thiosulfate are used in the chemical ageing process. During chemical ageing and before and reaction of the thiosulfate is substantially completed, the sensitizer is added.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a silver halide photographic emulsion and a method for producing the same.

[0002]

Conventionally, it is well known to chemically sensitize a silver halide photographic emulsion with a sulfur sensitizer. Observation of silver sulfide formed at this time with an electron microscope is, for example,
G.C.Farnell, P.B.Flint, D.C.Birch (JP Svol.25 P.20)
3).

Their observations indicate that many silver sulfide nuclei are present on AgX grains.

In the case of sulfur sensitization, the photographic speed is basically determined by the silver sulfide formation site, number and density, size and composition, and it is necessary to control these to the state where the latent image forming efficiency is highest. These control factors are the same in sulfur sensitization, gold sulfur sensitization, and noble metal sensitization, and it is known that there are optimum conditions in combination with silver halide grains.

However, in the conventionally known chemical sensitization method, the technical means for controlling the number and size of the chemical sensitized nuclei is incomplete, and it is very difficult to control all these parameters. It was

For example, regarding the control of the site for forming chemically sensitized nuclei, JP-A-64-40938 and JP-A-64-40938.
-62631, 64-62632, 64-74
540, JP-A-1-158425, 2-34,
Although there are many descriptions such as JP-A-2-298935, these only specify the site for forming chemical sensitization, and there is no description about the size of the chemical sensitization nucleus which is most important for improving the sensitivity. Similarly, JP-A-61-93447 describes selective growth of chemically sensitized nuclei composed of silver sulfide, gold sulfide, or a mixture thereof, which also forms a chemically sensitized nucleus. Site regulations, number,
There is no disclosure of size control means.

As a result of our study, it has been found that the recent demand for higher sensitivity and an image with less fog cannot be sufficiently fulfilled only by controlling the formation position of such a chemical sensitized nucleus.

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a silver halide photographic emulsion capable of obtaining an excellent image with low fog and high sensitivity, and a method for producing the same.

[0009]

The above object of the present invention is achieved by the following constitution.

[0010] 1. A sensitizer represented by the following general formula (1) and a thiosulfate are used during chemical ripening, and during the chemical ripening,
A silver halide photographic emulsion characterized by being prepared by adding a sensitizer represented by the general formula (1) before the reaction of thiosulfate is substantially completed.

General formula (1) [N (R ₁ ) (R ₂ )] [N (R ₃ ) (R ₄ )]> C = X In the formula, X represents S, Se or Te. R ₁ , R ₂ ,
R ₃ and R ₄ represent a hydrogen atom, an amidino group, an alkyl group, an aryl group or a heterocyclic residue.

R ₁ , R ₂ , R ₃ and R ₄ may be the same or different.

2. At the time of chemical ripening, the sensitizer and thiosulfate represented by the general formula (1) are used, and at the time of the chemical ripening,
A method for producing a silver halide photographic emulsion, which comprises adding the sensitizer represented by the general formula (1) before the reaction of the thiosulfate is substantially completed.

Hereinafter, the present invention will be described in more detail.

During the chemical ripening, a sensitizer represented by the general formula (1) (hereinafter, also simply referred to as the sensitizer of the present invention) and a thiosulfate are used, and the reaction of the thiosulfate is performed during the chemical ripening. Before the reaction is substantially completed, the sensitizer represented by the general formula (1) is added, and preferably, the unreacted thiosulfate is added to 5 times.
Addition of the sensitizer represented by the general formula (1) in the presence of 0% or more, more preferably before addition of thiosulfate, and further preferably, the general formula (1) The thiosulfate is added after the reaction of the sensitizer shown is completed.

In the present invention, the reaction of thiosulfate is substantially completed when the unreacted thiosulfate present in the silver halide photographic emulsion is less than 1% of the total amount of thiosulfate added. State

In the general formula (1), X represents S, Se or Te. Of these, S is preferable as X. R
₁ , R ₂ , R ₃ and R ₄ are each a hydrogen atom, an amidino group, an alkyl group (eg, each group such as methyl, ethyl, propyl, isopropyl), an aryl group (eg, each group such as phenyl, naphthyl) or hetero. It represents a ring residue (for example, a residue of thiazole, isothiazyl, thiadiazole, benzothiazole, etc.). Each of these groups may be substituted, and examples thereof include a halogen atom (atoms such as chlorine, bromine and iodine), an amino group, an alkyl group (for example, each group such as methyl, ethyl, propyl and isopropyl), an aryl group ( For example, each group such as phenyl and naphthyl) and the like can be mentioned. R ₁ ,
R ₂ , R ₃ and R ₄ may be the same or different.

The thiosulfate of the present invention is a compound represented by the following general formulas (2) and (3).

General formula (2) M ₁ ^I M ₂ ^II S ₂ O ₃ General formula (3) M ^II S ₂ O _{3 In} general formula (2) and general formula (3), M ₁ ^I and M ₂ ^I are 1
Valence cation, M ^II is a divalent cation.

The thiosulfate of the present invention is a compound which decomposes to form silver sulfide on the surface of silver halide grains, and
As long as M ₁ ^I , M ₂ ^I , M ^II and the by-products of the decomposition do not significantly deteriorate the photographic performance in the emulsion, any may be used, but preferred are M ₁ ^I , M ₂ ^I is NH ⁴⁺ , K ⁺ , Na ⁺ , and M ^II is Ca ²⁺ , and Na ⁺ is particularly preferable.

Specific compounds of the sensitizer of the present invention are shown below, but the present invention is not limited thereto.

[0022]

Embedded image In the present invention, a sensitizer other than the above may be further used in combination, and the sensitizer may be selected from any compound containing a sulfur atom, a selenium atom, or a tellurium atom.

Regarding the combined use of a thiosulfate and a sensitizer represented by the general formula (1), JP-A-1-130149.
No. 2, JP-A-2-198042, JP-A-5-12729
As described in No. 0, etc., there is no stipulation on the method of adding the sensitizer represented by the general formula (1) and the thiosulfate, and the sensitizer represented by the general formula (1) of the present invention It can be said that this is essentially different from the selective growth due to the catalytic effect of the chemically sensitized nuclei formed in.

The sensitizer containing sulfur, selenium, tellurium, etc. of the present invention is described in, for example, Chem. Rev. , 55,181 (1
955), Chem. Ber. , 63, 208 (193
0); Org. Chem. , 36, 3895 (19
71), J. Chem. Soc. , 1957, 2999
It can be easily synthesized using the method described in et al.

When a gold-containing compound is used in the present invention, Bull. Chem. Soc. Japan. , 48
(3), 1024-9 (1975), J. Inorg,
Nucl. Chem. , 38 (1), 7-11 (197)
6), TransitionMet. Chem. , 2
(6), 224-227 (1977) and JP-A-1-1.
It can be synthesized according to the method described in No. 47537.

Compounds containing a Group VIII noble metal are Aldri
ch Chemical Company, Johon
sold at Son Mathey Company, etc., and can be easily purchased.

The compound containing sulfur, selenium, tellurium and a noble metal of group VIII used in the present invention is dissolved in water or a water-miscible solvent such as methanol, ethanol or fluoroalcohol, alone or in a mixed solvent to form silver halide grains. It is preferably added to the emulsion. When the compound is hardly soluble in a suitable solvent, it is preferably added in the form of a dispersion.

Regarding the measurement of the reaction rate of sodium thiosulfate in the emulsion, the method using the radioactive isotope ³⁵ S is as follows.
H. Takiguchi (J. Imaging. Sci., Vo
l. 32, p. 20 (1988)). The reaction rate of the thiosulfate of the present invention can be measured by using this method.

If the thiosulfate is added after forming the silver sulfide nucleus on the surface of the silver halide grain with the sensitizer of the present invention, which is a preferred embodiment of the present invention, the sensitizer of the present invention is not added. It was revealed that the reaction of thiosulfate was significantly accelerated as compared with the case. Furthermore, it was confirmed that the reaction rate in this case was obviously higher than that of the thiosulfate added after the silver sulfide nucleus was formed using thiosulfate. It is considered to be a special phenomenon that appears only when silver sulfide nuclei are formed using the sensitizer of the present invention.

Further, the observation of the chemically sensitized nuclei formed on the surface of the silver halide grain by an electron microscope is carried out, for example, by G.C.Fernel, PB.Flint, D.C.Birch (JPS). vol.25 P.203)
However, using this method, a chemical sensitizing nucleus formed after addition of the sensitizer of the present invention and a thiosulfate salt after addition of the sensitizer of the present invention are preferable embodiments of the present invention. As a result of observing the chemically sensitized nuclei after the reaction was substantially completed, it was revealed that thiosulfate selectively grows silver sulfide nuclei formed by the sensitizer of the present invention. became.

From the above experimental results, the chemically sensitized nuclei formed by the sensitizer of the present invention act as the catalytic nuclei of thiosulfate to accelerate the reaction, and therefore the chemically sensitized nuclei themselves grow. It became clear.

Surprisingly, when a sensitizer of the present invention, which is a preferred embodiment of the present invention, is added and then a thiosulfate is added for ripening, the photographic sensitivity is remarkably increased. Was confirmed. The reason why the sensitivity is increased by the sensitizer of the present invention is not clear, but it is effective in latent image formation because the preformed silver sulfide nucleus is selectively grown by the thiosulfate added later. It is thought that this is due to the formation of a few deep deep electron traps.

That is, it was found that by using this method, it is possible to control the formation state of the chemically sensitized nuclei, and by doing so, high sensitivity can be achieved.

The composition of the silver halide contained in the silver halide photographic emulsion of the present invention is not particularly limited, and silver chloride and silver bromochloride, silver iodochloride, silver iodobromochloride, silver bromide, silver iodobromide. About the effect is recognized. Among these, silver bromochloride, silver bromide and silver iodobromide are preferable, and silver iodobromide is particularly preferable.

In the case of a silver iodobromide emulsion, the core of the silver halide grains contained in the silver halide photographic emulsion of the present invention is
It consists essentially of silver iodobromide, which contains 5 mol% of silver iodide.
It is preferable that the core substantially consists of the silver iodobromide contained above. The silver halide grains coat the core,
It is constituted by a silver iodobromide or a shell consisting essentially of silver bromide having a silver iodide content lower than that of the core. The silver iodide content of the core is more preferably 10 mol% or more, and most preferably 20 mol% or more and 44 mol% or less. The silver iodide content of the shell is 5 mol%
The following is preferred.

The above-mentioned core may contain silver iodide uniformly, or may have a multiple structure composed of phases having different silver iodide contents. In the latter case, the silver iodide content of the phase having the highest silver iodide content is preferably 5 mol% or more, more preferably 10 mol% or more, and the silver iodide content of the shell is It is preferred if the ratio is lower than that of the maximum silver iodide content phase of the core.

The silver halide of the present invention is a compound containing silver and chlorine, bromine and iodine alone or as a halogen at the same time, and other components may be, for example, up to about 1 mol%, for example, 1 mol%. It means that it may be contained up to about mol%.

A more preferred embodiment of the silver halide grains used in the silver halide photographic emulsion layer of the silver halide photographic light-sensitive material (hereinafter, also simply referred to as light-sensitive material) used in the present invention has a diffraction angle (2θ) of 38 to. Cu of Cu in the range of 42 °
When a curve of the diffraction intensity vs. angle of diffraction of the (220) plane of silver halide was obtained using β-rays, two diffraction peaks corresponding to the core part and the peak corresponding to the shell part,
It is preferable that the silver halide grains have a structure in which one minimum appears and the diffraction intensity corresponding to the core portion is 1/10 to 3/1 of that of the shell portion. The diffraction intensity ratio is more preferably 1/5 to 3/1, and particularly preferably 1/3 to 3/1.

Due to such double structuring and selective growth of chemically sensitized nuclei as in the present invention, a silver iodobromide emulsion having a high silver iodide content can be used without causing a delay in the developing rate. This makes it possible to produce a light-sensitive material having excellent graininess even with a small coating amount of silver.

In another preferred embodiment of the silver halide grains contained in the silver halide photographic emulsion of the present invention, the content of silver iodide forming a core inside the silver halide grains is 10%.
It is preferable to have a silver iodobromide phase of ˜40 mol%, and this silver iodobromide phase is coated with a silver halide phase containing a lower silver iodide which forms a shell portion. It is also preferable that the surface contains 5 mol% or more of silver iodide. The silver iodide composition contained in the shell part may be uniform or non-uniform. The surface contains 5 mol% or more of silver iodide means that the average content of silver iodide on the grain surface measured by XPS is 5 mol%.
It means that it is above. More preferably, the average content of silver iodide on the surface is 7 mol% or more and 15 mol% or less. The silver halide grains are described in JP-A-63-10.
6745.

The silver halide grains having a silver iodide content of the outermost layer higher than that of the intermediate layer are also included in the core / shell grains used in the present invention, but a chemical sensitizing nucleus having the features of the present invention is formed. By using the prepared silver halide grains,
For the first time, we were able to achieve high sensitivity. These silver halide grains are preferred because of their good graininess.

In another preferred embodiment of the silver halide grains contained in the silver halide photographic emulsion of the present invention, an internal core consisting essentially of silver iodobromide and / or silver iodide constitutes a core, A silver halide grain having a plurality of outer shells provided outside the core and consisting essentially of silver bromide and / or silver iodobromide, the outer shells forming shells,
The silver iodide content of the outermost shell is preferably 10 mol% or less, a silver iodide rich shell having a silver iodide content of 6 mol% or more higher than that of the outermost shell is preferable, and the inside of the outermost shell is An intermediate shell having a silver iodide content intermediate between these outer shells and the silver iodide-rich shell, and the intermediate shell contains silver iodide. The ratio is 3 mol% or more higher than the outermost shell, and the silver iodide content of the high silver iodide containing shell is 3 mol% or higher than the intermediate shell. The silver halide grains are described in detail in JP-A-61-245151.

In the silver halide photographic emulsion of the present invention, it is particularly preferable that the silver iodide content of individual silver halide grains is uniform from the viewpoint of uniformity of chemical sensitization and spectral sensitization.

The emulsion having a good uniformity of the silver iodide content as described above can be constituted by various means for improving the uniformity, and can be achieved by, for example, devising the production conditions of the silver halide emulsion.

For example, as disclosed in Japanese Patent Application No. 63-242002, a method for producing an emulsion in which silver iodide fine particles are used to supply iodide ions, and silver iodobromide fine particles as disclosed in JP-A-1-183417 are Ostwald-fused. A method of growing seed grains by aging is useful.

A preferred silver halide composition as the silver halide constituting the silver halide photographic emulsion of the present invention is 30
It is preferably silver iodobromide containing silver iodide in an amount of not more than mol%. Particularly preferred is silver iodobromide containing 2 to 20 mol% of silver iodide.

In order to achieve both high sensitivity and high image quality, the average silver iodide content of silver halide in all silver halide photographic emulsion layers is contained as described in JP-A-60-128443. The ratio is preferably 8 mol% or more.
It is known that the graininess is remarkably improved by increasing the average silver iodide content of silver halide. However, when the silver iodide content exceeds a certain level, the development speed is delayed, the desilvering and the fixing speed are increased. Defects such as delays will appear.

In this respect, as described above, the silver halide photographic emulsion of the present invention overcomes this problem, can increase the average silver iodide content, and has solved such a problem.

In order to form the light-sensitive material used in the present invention, an emulsion other than the silver halide photographic emulsion of the present invention can be used in combination, if necessary. In this case, the silver halide composition of the silver halide photographic emulsion used in combination is arbitrary, and examples thereof include silver bromide, silver iodobromide, silver iodochlorobromide, silver chlorobromide and silver chloride, and mixtures thereof. Either may be used.

The silver halide photographic emulsion of the present invention, or a silver halide photographic emulsion other than the present invention which is used in combination if necessary (hereinafter collectively referred to as "emulsion used in the present invention") has an average grain size of Coefficient of variation (JP-A-59-152438)
A monodisperse emulsion having a ratio of 16% or less (according to the formula described in No. 1) is preferred.

The shape of the silver halide grains in the emulsion used in the present invention, for example, the above monodisperse silver halide emulsion may be cubic, octahedral, tetradecahedral, spherical, or plate-like. However, a twin twin crystal having an average aspect ratio of 3 or more is preferably used. The average aspect ratio referred to here is (diameter of tabular grain) /
It is the average value of the aspect ratio represented by (thickness of tabular grains). Further, the diameter of tabular grains means the diameter of a circle having an area equal to the projected area of silver halide grains when the tabular grains are observed with an optical microscope or an electron microscope. The tabular grain thickness is indicated by the distance between two parallel principal planes of the tabular grain.

The average grain size of silver halide emulsion grains used in the present invention is preferably 0.1 to 5.0 μm, more preferably 0.15 to 3.0 μm, and particularly preferably 0.2 to 2 μm. It is 0.0 μm.

Monodisperse emulsions are preferable because they have good graininess and, at the same time, have a sharpness of an image in the size range where light scattering is small. Monodisperse emulsions are described, for example, in JP-A-54-48521 and JP-A-54-99419.
Nos. 56-16124, 56-78831, U.S. Pat. No. 4,444,877, and JP-A-57-1827.
No. 30, No. 58-49938, No. 58-37635
No. 4,446,228, JP-A-58-1
No. 06532, No. 58-107530, No. 58-12
No. 6531, No. 58-149037, No. 59-109
No. 47, No. 59-29243, No. 59-72440
No. 59-140443, No. 59-148049
And Nos. 59-177535 and 59-152438.

The silver halide photographic emulsion of the present invention, which is used in the case of constituting the light-sensitive material used in the present invention,
In addition, silver halide emulsions other than the silver halide photographic emulsion of the present invention which are optionally used are preferably those which have undergone physical ripening, chemical ripening and generally spectral sensitization according to each color photosensitive layer to be used. use.

Additives that can be used in such a process are Research Disclosure No. 17643, no.
18716, and No. 308119 (each,
RD17643, RD18716 and RD308119
Abbreviated).

The places described below are shown.

Item RD308119 Page RD17643 RD18716 and Item Page Page Chemical sensitizer 996 III-A Item 23 648 Spectral sensitizer 996 IV-A-A, B 23-24 648-9 C, D, H , I, J item Supersensitizer 996 IV-A-E, J item 23-24 648-9 Antifoggant 998 VI 24-25 649 Stabilizer 998 VI 24-25 649 Also used in the practice of the present invention The known photographic additives that can be used are also exemplified in the above-mentioned Research Disclosure. Shown below are the relevant locations.

Item RD308119 Page RD17643 RD18716 and Item Page Page Color turbidity inhibitor 1002 VII-I Item 25 650 Dye image stabilizer 1002 VII-J Item 25 Whitening agent 998 V 24 UV absorber 1003 VIIIC, XIIIC Item 25-26 Light absorber 1003 VIII 25-26 Light scattering agent 1003 VIII Filter dye 1003 VIII 25-26 Binder 1003 IX 26 651 Antistatic agent 1006 XIII 27 650 Hardener 1004 X 26 651 Plasticizer 1006 XII 27 650 Lubrication Agent 1006 XII 27 650 Activator / Coating aid 1005 XI 26 to 27 650 Matting agent 1007 XVI Developer 1011 XXB (Contained in light-sensitive material) The light-sensitive material used in the present invention includes:
Various couplers can be used depending on the color to be developed in each color photosensitive layer, and specific examples thereof are described in Research Disclosure above. The relevant locations are shown below.

Item Page of RD308119 RD17643 Yellow coupler 1001 VII-D item VII C to G item Magenta coupler 1001 VII-D item VII C to G item Cyan coupler 1001 VII-D item VII C to G item Colored coupler 1002 VII- Item G VII Item G DIR coupler 1001 VII-F item VII F item BAR coupler 1002 VII-F Other useful residue 1001 VII-F item releasing coupler Alkali-soluble coupler 1001 VII-E Photosensitive material used in the present invention When various additives are used in the above, they can be added by the dispersion method described in RD308119XIV.

In the present invention, the above-mentioned RD17643 is used.
28, RD 18716, pages 647-8, and RD 308119, XVII.

The light-sensitive material used in the present invention may be provided with an auxiliary layer such as a filter layer or an intermediate layer described in the above item RD308119VII-K.

The light-sensitive material used in the present invention is the above-mentioned RD.
308119, section VII-K, forward layer, reverse layer,
Various layer configurations such as a unit configuration can be adopted.

The silver halide photographic emulsion of the present invention is a color negative film for general use or movies, a color reversal film for slides or televisions, color paper,
It can be applied to various color light-sensitive materials represented by color positive films and color reversal paper.

The light-sensitive material used in the present invention is RD17.
It can be processed by the conventional method described in pages 28-29 of 643, pages 615 of RD18716, and section XIX of RD308119.

[0065]

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

First, the emulsion Em- used in this example is described below.
Preparation of Emulsion Em-A which describes the preparation method of A and Em-B The following aqueous solutions (a-1) to (a-6) which describe the preparation method of Emulsion A were used.

Aqueous solution (a-1) Gelatin 102.2 g 28% Ammonia 155.4 ml 56% Acetic acid 93.2 ml Water 9500 ml Aqueous solution (a-2) 56% Acetic acid 3000 ml Aqueous solution (a-3) Seed emulsion 0.22 mol equivalent ( 0.3 μm) Aqueous solution (a-4) Gelatin 120.0 g Potassium bromide 1499.4 g Water 5364.8 ml Aqueous solution (a-5) Silver nitrate 1871.6 g 28% ammonia 1465.8 ml Water is added 5049.4 ml Aqueous solution (a -6) Potassium bromide 400 g Water 960 ml After adding the aqueous solution (a-2) to the aqueous solution (a-1) of the above composition which was vigorously stirred at a temperature of 40 ° C., pH was adjusted to 9.00 with 28% ammonia. Adjusted to an aqueous solution (a-3)
Is added. After that, aqueous solution (a-4), (a-5)
Was added at the flow rates shown below, and pH and EAg were controlled using the aqueous solution (a-6) as shown below.

[0068] Then, a phenylcarbamine gelatin solution was added to the resulting solution to adjust the pH of the solution to cause the particles to aggregate and precipitate, followed by washing with desalted water. In this way, 1 μm tetradecahedral grains could be formed.

Preparation of Emulsion Em-B A method for preparing Emulsion Em-B will be described.

Emulsion Em-B consisting of tabular twin crystals was prepared by using a monodisperse twin seed emulsion having an average grain size of 0.36 μm and a wide distribution (variation coefficient) of 18% and the following five kinds of solutions. did.

(B-1) Ocein gelatin 97 g Propyleneoxy-polyethyleneoxy-disuccinate disodium salt (10% methanol solution) 10 ml Seed emulsion 0.191 mol equivalent Water 400 ml (b-2) Silver nitrate 233 g Water 1662 ml (b -3) Ocein gelatin 83.1 g Potassium bromide 131 g Potassium iodide 45.5 g Water 1662 ml (b-4) Silver nitrate 934 g Water 2749 ml (b-5) Ocein gelatin 137 g Potassium bromide 635 g Potassium iodide 27. 4g Water 2749ml Solution (b-1) solution (b-2) and solution (b-3) were vigorously stirred at 75 ° C by a double jet method to give an initial flow rate of 8.6 ml / min and a final flow rate of 25 ml. Accelerated addition was performed so that the rate of increase increased linearly with the addition time in minutes. At this time p
Ag was kept at 8.5.

Subsequently, the solution (b-4) and the solution (b-5) were added at an accelerated rate so that the initial flow rate was 15 ml / min and the final flow rate was 34 ml / min, which increased linearly with the addition time. . At this time, pAg was maintained at 9.0.

Solution (b-2), Solution (b-3), (b-4)
In addition of the solution and the solution (b-5), the pH was kept at 3.0 throughout using nitric acid.

After the addition was completed, the pH was adjusted to 6.0 using an aqueous potassium hydroxide solution. In order to remove excess salts, precipitation and desalting were performed using an aqueous solution of Demol (manufactured by Kao Atlas) and an aqueous solution of magnesium sulfate, and pAg8.
An emulsion having a pH of 5.85 was obtained at 5,40 ° C.

When the obtained emulsion Em-B was observed with an electron microscope, 75% of the total projected area was occupied by tabular grains, the average projected area grain size was 1.5 μm, and the average aspect ratio was 3.5. Met.

Example 1 Emulsion A-1: The pAg of emulsion Em-A was adjusted to 8.0 at 40 ° C., and the ripening temperature was kept constant at 55 ° C. from the beginning to the end of ripening at 6.5 × 10 ⁻⁴ mol / ^min. Molar AgX sodium thiosulfate was added instantaneously and aged for 120 minutes.

Emulsion A-2: Aging was carried out by the same method except that the sodium thiosulfate of Emulsion A-1 was changed to 1-ethyl-3- (2-thiazolyl) -thiourea.

Emulsion A-3: The same ripening as Emulsion A-2 was carried out to 1.
6.5 × 10 ⁻⁴ mol / mol Ag was added to the emulsion for 20 minutes.
Sodium thiosulfate (X) was added and the mixture was aged for 120 minutes.

These emulsions A-1, A-2, and A-3 were observed by an electron microscope by the gelatin wrap method, and their photographs are shown in FIGS.

Emulsion A-1 and Emulsion A-2 are Comparative Examples, Emulsion A
-3 is the present invention.

In Emulsion A-2, it was observed that silver sulfide nuclei were formed in the vicinity of the ridgeline of silver halide. In Emulsion A-3 further ripened with sodium thiosulfate, it was A-2. It is observed that silver sulfide nuclei near the observed ridge line are selectively growing.

Since the silver sulfide nuclei formed by sodium thiosulfate alone are not selectively formed on the ridges as shown in Emulsion A-1, the silver sulfide nuclei formed by the sensitizer of the present invention. Indicates that it works as a catalyst nucleus.

Further, as a result of comparing the silver sulfide nucleation reaction rates of the sodium thiosulfates of the emulsions A-1 and A-3, the silver sulfide nucleation reaction rate was 1-ethyl-3 as shown in FIG.
Emulsion A-3 of the present invention is significantly different from that of Comparative Emulsion A-1 with or without addition of-(2-thiazolyl) -thiourea.
It can be seen that the reaction rate of silver sulfide nucleation is higher than that of.
In FIG. 4, the vertical axis represents the reaction rate, and the horizontal axis represents the chemical ripening time with the start of ripening at the time when sodium thiosulfate was added.

Example 2 Emulsion B prepared above was divided into 10 parts, and then chemically and spectrally sensitized as follows.
-1 to B-10.

Emulsion B-1 The ripening temperature was kept constant at 55 ° C. from the initial stage to the end of ripening, and spectral sensitization was carried out by using sensitizing dyes SD-6, 7, and 8 together. 10
After aging for 1 minute, 1.3 × 10 ⁻⁶ mol / mol AgX of sodium thiosulfate was added, and 120 minutes later, chloroauric acid was added.
A mixed solution of 8 × 10 ⁻⁷ mol / mol AgX and ammonium thiocyanate 2 × 10 ⁻⁵ mol / mol AgX was added and the mixture was aged for 60 minutes. This emulsion is designated as B-1. Emulsion B-2 Spectral sensitization was carried out by using the sensitizing dyes SD-6, 7, and 8 together with the ripening temperature kept constant at 55 ° C from the initial stage to the end of ripening. 10
After aging for 6 minutes, 6.5 × 10 ⁻⁷ mol / mol of AgX 1
-Ethyl-3- (2-thiazolyl) -thiourea was added and after a further 30 minutes sodium thiosulfate 6.5 x 10
^-7 mol / mol AgX was added. After 120 minutes, a mixed solution of 2.8 × 10 ⁻⁷ mol / mol AgX of chloroauric acid and 2.0 × 10 ⁻⁵ mol / mol AgX of ammonium thiocyanate was added and the mixture was aged for 60 minutes. This emulsion is designated as B-2.

Emulsion B-3 An emulsion ripened in the same manner as in Emulsion B-2 except that 1-ethyl-3- (2-thiazolyl) -thiourea in Emulsion B-2 was replaced with 1,1,3-triethyl-1-thiourea was B-. Set to 3.

Emulsion B-4 Emulsion B-2 is an emulsion aged in the same manner except that 1-ethyl-3- (2-thiazolyl) -thiourea of Emulsion B-2 was replaced with 1,1-diphenyl-thiourea. .

Emulsion B-5 Emulsion B-2 is an emulsion aged in the same manner except that 1-ethyl-3- (2-thiazolyl) -thiourea of Emulsion B-2 was replaced with 1,1-dimethyl-selenourea. .

Emulsion B-6 Sodium thiosulfate of Emulsion B-1 was replaced with 1,1-dimethyl-
An emulsion aged in the same manner except that it was replaced with selenourea was designated as B-6.

Emulsion B-7 The ripening temperature was kept constant at 55 ° C. from the initial stage to the end of ripening, and the sensitizing dyes SD-6, 7 and 8 were used together for spectral sensitization. 10
After aging for minutes, 6.5 × 10 ⁻⁷ mol / mol AgX of sodium thiosulfate was added, and 6.5 × 10 ⁻⁷ mol / mol A of sodium thiosulfate was added before the reaction of sodium thiosulfate was substantially completed.
gX of 1-ethyl-3- (2-thiazolyl) -thiourea was added. After 120 minutes, chloroauric acid 2.8 × 10 ⁻⁷ mol / mol AgX and ammonium thiocyanate 2.0 × 1
A mixed solution of 0 ⁻⁵ mol / mol AgX was added and the mixture was aged for 60 minutes. This emulsion is designated as B-7.

Emulsion B-8 The ripening temperature was kept constant at 55 ° C. from the initial stage to the end of ripening, and the sensitizing dyes SD-6, 7 and 8 were used together for spectral sensitization. 1
After aging for 0 minutes, sodium thiosulfate 6.5 × 10 ^-7
Mol / mol AgX was added and further aged. When the unreacted sodium thiosulfate in the emulsion reached 75% of the added amount, 6.5 × 10 ⁻⁷ mol / mol AgX of 1-ethyl-3- (2-thiazolyl) -thiourea was added. . After 120 minutes, chloroauric acid 2.8 × 10 ⁻⁷ mol / mol A
gX and ammonium thiocyanate 2.0 × 10 ⁻⁵ mol /
A mixed solution of mol AgX was added and aged for 60 minutes. This emulsion is designated as B-8.

Emulsion B-9 The ripening temperature was kept constant at 55 ° C. from the initial stage until the end of ripening, and spectral sensitization was carried out by using sensitizing dyes SD-6, 7, and 8 together. 1
After aging for 0 minutes, sodium thiosulfate 6.5 × 10 ^-7
Mol / mol AgX was added and further aged. When the unreacted sodium thiosulfate in the emulsion reached 25% of the added amount, 6.5 × 10 ⁻⁷ mol / mol AgX of 1-ethyl-3- (2-thiazolyl) -thiourea was added. . After 120 minutes, chloroauric acid 2.8 × 10 ⁻⁷ mol / mol A
gX and ammonium thiocyanate 2.0 × 10 ⁻⁵ mol /
A mixed solution of mol AgX was added and aged for 60 minutes. This emulsion is designated as B-9.

Emulsion B-10 From the initial stage until the end of ripening, the ripening temperature was kept constant at 55 ° C. and the sensitizing dyes SD-6, 7 and 8 were used together for spectral sensitization. 1
After aging for 0 minutes, sodium thiosulfate 6.5 × 10 ^-7
Mol / mol AgX was added and further aged. When the amount of unreacted sodium thiosulfate in the emulsion was less than 1% of the added amount and the reaction was substantially completed, 6.5 × 10 ⁻⁷ mol / mol of AgX 1-ethyl-3- (2- Thiazolyl)
-Thiourea was added. After 120 minutes, chloroauric acid 2.
A mixed solution of 8 × 10 ⁻⁷ mol / mol AgX and ammonium thiocyanate 2.0 × 10 ⁻⁵ mol / mol AgX was added and the mixture was aged for 60 minutes. This emulsion is designated as B-10.

Using the above emulsion, the multilayer sample No. 101
To 110 were produced. Basic multilayer sample No. 101
The configuration of is shown below.

In all the following descriptions, the amount of the compound added to the AgX photographic light-sensitive material is 1 unless otherwise specified.
Indicates the number of grams per m ² .

Further, AgX and colloidal silver are shown in terms of silver, and the addition amount of the sensitizing dye is shown by the number of moles per 1 mole of AgX in the same layer.

Sample-101 First Layer: Antihalation Layer (HC-1) Black Colloidal Silver 0.2 UV Absorber (UV-1) 0.23 High Boiling Solvent (Oil-1: Dioctylphthalate) 0.18 Gelatin 1.4 Second Layer; Intermediate Layer (IL-1) Gelatin 1.3 Third Layer; Low Sensitivity Red Sensitive Emulsion Layer (RL) Silver iodobromide emulsion (grain size 0.40 μm, average AgI content 8.0) Mol%) 1.0 Sensitizing dye (SD-1) 1.8 × 10 ⁻⁵ Sensitizing dye (SD-2) 2.8 × 10 ⁻⁴ Sensitizing dye (SD-3) 3.0 × 10 ^{− 4} Cyan coupler (C-1) 0.70 Colored cyan coupler (CC-1) 0.066 DIR compound (D-1) 0.03 DIR compound (D-3) 0.01 High boiling point solvent (Oil-1) 0.64 Gelatin 1.2 4th layer; Medium sensitivity red-sensitive emulsion layer (RM) Odor Silver emulsion (particle size 0.7 [mu] m, an average AgI content of 8.0 mol%) 0.8 Sensitizing dye (SD─1) 2.1 × 10 ^-5 Sensitizing dye (SD─2) 1.9 × 10 ^-4 Sensitizing dye (SD-3) 1.9 × 10 ^-4 Cyan coupler (C-1) 0.28 Colored cyan coupler (CC-1) 0.027 DIR compound (D-1) 0.01 High boiling point Solvent (Oil-1) 0.26 Gelatin 0.6 Fifth layer; High-sensitivity red-sensitive emulsion layer (RH) Silver iodobromide emulsion (Emulsion B) 1.70 Sensitizing dye (SD-1) 1.9x 10 ^-5 Sensitizing dye (SD-2) 1.7 × 10 ^-4 Sensitizing dye (SD-3) 1.7 × 10 ^-4 Cyan coupler (C-1) 0.05 Cyan coupler (C-2) 0.10 Colored cyan coupler (CC-1) 0.02 DIR compound (D-1) 0.025 High boiling point solvent (Oil-1) 0.1 Gelatin 1.2 Sixth layer; Intermediate layer (IL-2) Gelatin 0.8 Seventh layer; Low sensitivity green sensitive emulsion layer (GL) Silver iodobromide emulsion (grain size 0.4 μm, average AgI content 8. 0 mol%) 1.1 Sensitizing dye (SD-4) 6.8 × 10 ^-5 Sensitizing dye (SD- ⁵ ) 6.2 × 10 ^-4 Magenta coupler (M-1) 0.54 Magenta coupler ( M-2) 0.19 Colored magenta coupler (CM-1) 0.06 DIR compound (D-2) 0.017 DIR compound (D-3) 0.01 High boiling point solvent (Oil-2: tricresyl phosphate) ) 0.81 gelatin 1.8 eighth layer; medium-speed green-sensitive emulsion layer (GM) silver iodobromide emulsion (particle size 0.7 μm, average AgI content 8.0 mol%) 0.7 sensitizing dye ( SD─6) 1.9 × 10 ^-4 sensitizing dye (SD─7) 1.2 × 10 ^-4 sensitizing dye (S ─8) 1.5 × 10 ^-5 Magenta coupler (M─1) 0.07 Magenta coupler (M-2) 0.03 Colored magenta coupler (CM─1) 0.04 DIR compound (D─2) 0. High boiling point solvent (Oil-2) 0.30 Gelatin 0.8 9th layer; High-sensitivity green sensitive emulsion layer (GH) Silver iodobromide emulsion (Emulsion B-1) 1.7 Sensitizing dye (SD-6) ) 1.2 × 10 ^-4 sensitizing dye (SD-7) 1.0 × 10 ^-4 sensitizing dye (SD-8) 3.4 × 10 ^-6 magenta coupler (M-1) 0.09 magenta coupler (M-3) 0.04 Colored magenta coupler (CM-1) 0.04 High boiling point solvent (Oil-2) 0.31 Gelatin 1.2 10th layer; Yellow filter layer (YC) Yellow colloidal silver 0.05 Color stain inhibitor (SC-1) 0.1 High boiling solvent (Oil -2) 0.13 gelatin 0.7 formalin scavenger (HS-1: 5-ureidohydantoin) formalin scavenger (HS-2: hydantoin) 0.07 11th layer; low-sensitivity blue-sensitive emulsion layer (BL) iodobromide Silver emulsion (particle size 0.4 μm, average AgI content 8.0 mol%) 0.5 Silver iodobromide emulsion (particle size 0.7 μm, average AgI content 8.0 mol%) 0.5 Sensitizing dye (SD-9) 5.2 × 10 ^-4 Sensitizing dye (SD-10) 1.9 × 10 ^-5 Yellow coupler (Y-1) 0.65 Yellow coupler (Y-2) 0.24 DIR compound ( D-1) 0.03 High boiling point solvent (Oil-2) 0.18 Gelatin 1.3 Formalin scavenger (HS-1) 0.08 12th layer; High-sensitivity blue-sensitive emulsion layer (BH) Silver iodobromide emulsion (Emulsion B) 1.0 Sensitizing dye ( D-9) 1.8 × 10 ^-4 Sensitizing dye (SD-10) 7.9 × 10 -5 Yellow coupler (Y─1) 0.15 Yellow coupler (Y─2) 0.05 High boiling solvent ( Oil-2) 0.074 Gelatin 1.3 Formalin scavenger (HS-1) 0.05 Formalin scavenger (HS-2) 0.12 13th layer; 1st protective layer (Pro-1) Fine grain silver iodobromide emulsion 0.4 (Average particle size 0.08 μm Average AgI content 1 mol%) UV absorber (UV-1) 0.07 UV absorber (UV-2) 0.10 High boiling point solvent (Oil-1) 07 High boiling point solvent (Oil-3: dibutyl phthalate) 0.07 Formalin scavenger (HS-1) 0.13 Formalin scavenger (HS-2) 0.37 Gelatin 1.3 14th layer; 2nd protective layer (Pr) o-2) Alkali-soluble matting agent (average particle size 2 μm) 0.13 Polymethylmethacrylate (average particle size 3 μm) 0.02 Sliding agent (WAX-1) 0.04 Gelatin 0.6 Next, emulsion for the ninth layer Sample No. 1 was made in the same manner except that B-1 was changed to B-2 to B-10. 102-110 were produced.

Sample No. The compounds used in 101 to 110 are shown below.

[0099]

Embedded image

[0100]

Embedded image

[0101]

Embedded image

[0102]

Embedded image

[0103]

[Chemical 6]

[0104]

[Chemical 7]

[0105]

Embedded image In addition to the above composition, coating aid sodium dioctylsulfosuccinate, dispersion aid sodium-tri (isopropyl) naphthalene sulfonate, viscosity modifier, hardener 2,4-dichloro-6-hydroxy-s-triazine Sodium salt, di (vinylsulfonylmethyl) ether,
Stabilizer 4-hydroxy-6-methyl-1,3,3a, 7
-Tetrazaindene, antifoggant 1-phenyl-5-
Mercaptotetrazole, weight average molecular weight 10,000
And 1,100,000 two poly-N-vinylpyrrolidones were added.

The above sample No. Wedge exposure was performed on 101 to 108 through a yellow filter, and then the following development processing was performed.

Treatment step (38 ° C.) Color development Standard 2 minutes 45 seconds Bleach 6 minutes 30 seconds Water washing 3 minutes 15 seconds Settling 6 minutes 30 seconds Water washing 3 minutes 15 seconds Stabilization 1 minute 30 seconds Dry each The composition of the processing liquid used in the processing step is as follows.

(Color Developer) 4-Amino-3-methyl-N-ethyl-N- (β-hydroxyethyl) aniline / sulfate 4.75 g anhydrous sodium sulfite 4.25 g hydroxylamine 1/2 sulfate 2 0.0 g anhydrous potassium carbonate 37.5 g sodium bromide 1.3 g nitrilotriacetic acid trisodium salt (monohydrate) 2.5 g potassium hydroxide 1.0 g Add water to make 1 liter (pH = 10.1) ( Bleach) Ethylenediaminetetraacetic acid iron (III) ammonium salt 100.0 g Ethylenediaminetetraacetic acid diammonium salt 10.0 g Ammonium bromide 150.0 g Glacial acetic acid 10.0 g Water was added to make 1 l, and pH was adjusted to 6.0 with ammonia water. Adjust to.

(Fixer) Ammonium thiosulfate 175.0 g Anhydrous sodium sulfite 8.5 g Sodium metasulfite 2.3 g Water is added to make 1 l, and pH is adjusted to 6.0 with acetic acid.

(Stabilizing Solution) Formalin (37% aqueous solution) 1.5 ml Conidax (manufactured by Konica Corporation) 7.5 ml Water is added to make 1 liter.

For each of the obtained samples, the sensitivity was defined as the reciprocal of the exposure amount giving a fog density + 0.1 measured using green light, and the sensitivity of Emulsion B-1 was defined as 100 and expressed as a relative sensitivity.

Emulsion Sensitivity Fog Remarks B-1 100 0.25 Comparison B-2 120 0.10 Present invention B-3 125 0.07 Present invention B-4 135 0.10 Present invention B-5 140 0.20 Present invention B-6 85 0.36 Comparison B-7 115 0.07 Present invention B-8 117 0.07 Present invention B-9 105 0.15 Present invention B-10 95 0.29 Comparison Clear from the above results As described above, the silver halide photographic light-sensitive material containing the emulsion of the present invention has high sensitivity and can produce excellent images with low fog.

[0113]

INDUSTRIAL APPLICABILITY The silver halide photographic emulsion and the method for producing the same according to the present invention can provide excellent images with low fog and high sensitivity.

[Brief description of drawings]

FIG. 1 is a silver halide emulsion A- shown in Example 1.
1 is a photograph (50,000 times) of chemically sensitized nuclei of No. 1 photographed by an electron microscope by a gelatin foreskin method.

2 is a silver halide emulsion A- shown in Example 1. FIG.
2 is a photograph (50,000 times) of chemically sensitized nuclei of 2 taken by an electron microscope by a gelatin foreskin method.

FIG. 3 is a photograph (50,000 times) of a chemically sensitized nucleus of the silver halide emulsion A-3 showing an example of the present invention shown in Example 1, taken by an electron microscope by a gelatin foreskin method.

FIG. 4 is a view showing a reaction rate of silver sulfide nucleus formation reaction of sodium thiosulfate.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Haruhiko Masutomi Konica Corporation, 1 Sakuracho, Hino-shi, Tokyo

Claims (2)

[Claims] 1. A sensitizer represented by the following general formula (1) and a thiosulfate are used at the time of chemical ripening, and at the time of the chemical aging, before the reaction of the thiosulfate is substantially completed, the above-mentioned general formula is used. A silver halide photographic emulsion produced by adding a sensitizer represented by (1). Formula (1) [N (R ₁₎ (R _2)] [N (R ₃₎ (R _4)]> C = X wherein, X represents a S, Se or Te. R ₁ , R ₂ , R
₃ , R ₄ represents a hydrogen atom, an amidino group, an alkyl group, an aryl group or a heterocyclic residue. R ₁ , R ₂ , R ₃ and R ₄ may be the same or different. ] 2. A sensitizer represented by the general formula (1) and a thiosulfate are used at the time of chemical ripening, and at the time of the chemical aging, before the reaction of the thiosulfate is substantially completed, the above-mentioned general formula A method for producing a silver halide photographic emulsion, which comprises adding a sensitizer represented by (1).