JPH0862752A - Silver halide photographic emulsion, silver halide photographic sensitive material, medical silver halide photographic sensitive material and method for processing same - Google Patents

Abstract

PURPOSE: To provide silver halide emulsion comprising flat silver halide grains superior in rapid processing aptitude and pressure characteristics, the silver halide photographic sensitive material and the one for medical treatment containing this emulsion, and the method for processing the medical photosensitive material. CONSTITUTION: The flat silver halide grains contained in the emulsion in >=50% of the projection areas of the total silver halide grains has an average aspect ratio of 2-5, and an average silver iodide content of <=0.8mol% and contains silver nuclei formed in the insides of these flat silver halide grains. Both of the photosensitive material and the medical photosensitive material contains this emulsion and the medical one is processed in the total processing time of 15-90sec.

Description

Detailed Description of the Invention

[0001]

The present invention relates to an emulsion containing tabular silver halide grains, a silver halide photographic light-sensitive material using the emulsion, particularly a medical silver halide photographic light-sensitive material, and a light-sensitive material thereof. It relates to a processing method.

[0002]

2. Description of the Related Art In recent years, silver halide photographic light-sensitive materials (hereinafter also simply referred to as light-sensitive materials) for medical development processing,
It is more and more desired to shorten the processing time and reduce the processing waste liquid. For example, in the medical field, the number of X-ray photographs taken increases, and the number of X-ray photographs taken increases, resulting in a rapid increase in development processing after regular medical examinations, widespread use of medical checkups, and examinations including general medical examinations. The demand for further reduction of processing waste liquid is increasing.

However, in order to speed up the processing, it is necessary to shorten the processing time of each processing step such as developing, fixing, washing with water, and drying, and the load on each step increases. For example, if the development time is simply shortened, in the conventional photosensitive material,
The image density is lowered, that is, the sensitivity is lowered and the gradation is deteriorated. Further, if the fixing time is shortened, the fixing of silver halide becomes incomplete, which causes deterioration of image quality. Therefore, in order to solve such a problem, it is necessary to accelerate the developing speed and the fixing speed.

In order to accelerate the developing speed and fixing speed,
It is preferable to reduce the silver iodide content of the silver halide grains. However, it is known that when the average silver iodide content is lowered, the intrinsic sensitivity of silver halide is lowered. When the silver iodide content on the silver halide surface is lowered, the adsorption of the spectral sensitizing dye is deteriorated and the spectral sensitivity is lowered.
It is known that the pressure characteristics may deteriorate. Further, it is known that if the silver iodide content inside the silver halide is lowered, the pressure characteristics may deteriorate.

Here, the pressure characteristics are two things: so-called pressure fog in which an unexposed portion is developed when pressure is applied to a silver halide photographic light-sensitive material, and pressure desensitization in which sensitivity is lowered during exposure. Means If these characteristics are poor, they will cause serious defects as a silver halide photographic light-sensitive material.

As described above, it is known that the silver iodide contained in the silver halide grains affects various photographic performances, and many patents and scientific literatures on the technology relating to the composition distribution of conventional silver iodide are disclosed. Has been done. For example, it is disclosed in Japanese Patent Application Laid-Open No. 4-107442 and patent publications cited therein. However, the technologies disclosed so far cannot satisfy the recent demands for higher sensitivity, higher image quality, and ultra-fast development processing.

By the way, in recent years, many techniques for improving sensitivity and image quality using tabular silver halide grains have been disclosed, and examples thereof are disclosed in JP-A-58-111935 and JP-A-58-111936.
No. 58-111937, No. 58-113927, No. 59-99433, etc.

These tabular silver halide grains are hexahedral,
Compared with so-called regular crystal silver halide grains such as octahedron, the surface area is large in the same volume, so it is possible to increase the adsorption amount of the sensitizing dye on the grain surface, and as a result, it is possible to achieve high sensitivity. There is.

Further, JP-A-63-92942 discloses a technique of providing a core having a high silver iodide content inside a tabular silver halide grain, and JP-A-63-151618 discloses a hexagonal tabular silver halide grain. Is disclosed, and the effect of increasing the sensitivity is shown.

In addition to this, JP-A-63-106746 and JP-A-1
-183644 and JP-A-1-279237 disclose techniques relating to the composition distribution of tabular silver halide grains.

On the other hand, many techniques for improving the drawbacks of tabular silver halide grains have been disclosed.

Tabular silver halide grains have the disadvantage of poor pressure characteristics. In general, silver halide grains are sensitive to pressure, and with increasing sensitivity, they become more sensitive to pressure, but in the case of tabular silver halide grains, the degree is It is remarkable. This means that when compared in the same volume, even if the materials have the same mechanical strength, the tabular grains are thinner than the spherical grains, so that a large moment is likely to be applied, and the mechanical strength of the grains as a whole is large. Interpreted as weak.

Further, the pressure characteristics differ depending on the conditions of chemical sensitization of silver halide grains in addition to the shape of silver halide. Generally, when the degree of chemical sensitization is insufficient (chemical ripening is insufficient), pressure desensitization is poor, and when the degree of chemical sensitization is excessive, pressure desensitization is reduced but pressure fog is deteriorated.

With respect to such deterioration of pressure characteristics, JP-A-59-99433, JP-A-60-35726, JP-A-60-147727, and JP-A-63-30.
1937, 63-149641, 63-106746, 63-151618
No. 63-220238, JP-A 1-131541, JP-A 2-19313
No. 8, No. 3-172836, No. 3-231739 and the like disclose means for improving the pressure characteristics, but these means have not been able to achieve a sufficient improvement effect.

As a technique for forming silver nuclei, reduction sensitization has long been known. For example, the Journal of Photographic Science
raphic Sciense) Vol. 25, pp. 19-27 (1977) and Photographic Science and Engineering (Photo
graphic Sciense and Engineering) Volume 23, 113-117
As described in (1979), silver nuclei formed by reduction sensitization are photographically correspondent (Photog
raphishe Korrespondenz) Volume 1, 20- (1957) and Photographic Science and Engineering
(Photographic Sciense and Engineering) Volume 19, 49-
As described by Michelle and Lowe in the report of 55 (1975), it has been thought to contribute to sensitization through the reaction shown below during exposure.

AgX + hv → e ⁻ + h ⁺ (1) Ag ₂ + h ⁺ → Ag ⁺ + Ag (2) Ag → Ag ⁺ + e ⁻ (3) where h ⁺ and e ⁻ are generated by exposure. Free holes and free electrons, hv represents photons, and Ag ₂ represents silver nuclei formed by reduction sensitization.

However, photographic science
And Engineering (Photographic Sciense and E
ngineering) 16, 35-42 (1971) and 23, 113.
According to pp. 117 (1979), silver nuclei have the property of trapping not only holes but also electrons, and the above theory alone is not always sufficient.

Further, in the spectrally sensitized grains, the behavior of reduction sensitization is even more complicated and difficult to predict because the sensitization process which is different from the intrinsic photosensitive region of the silver halide grains is carried out. It was

On the other hand, many techniques for putting reduction sensitization into practical use have been disclosed. As reduction sensitizers, tin compounds, polyamine compounds, thiourea dioxide, etc. have been proposed.
Further, as a condition for reduction sensitization, a method of aging at a high pH and a method of aging at a low pAg have been proposed. Further, many techniques for compensating for the drawback of reduction sensitization have been disclosed.

For example, Japanese Patent Application Laid-Open No. 2-919938 discloses that reduction sensitization and addition of a thiosulfonic acid compound are used in combination to achieve high sensitivity, reduction of fog and improvement of pressure resistance. In the above-mentioned patent, it is preferable that the halogen composition of the silver halide grains is not uniform and has a distribution, or that it has a structure such as a core-shell grain, but there is no description about a preferable range of the silver iodide content. . In particular, the silver iodide content of 0.8 mol% or less is not mentioned in the examples, and it is surprising that the sensitivity, pressure resistance, rapid processing suitability and the like are all improved by the constitution of the present invention.

Further, in JP-A-3-194537, a reduction-sensitized emulsion is used, and a light-sensitive material having an equilibrium pAg of 7 to 11 is used.
Although it shows that the storability of the light-sensitive material can be improved, there is no description about the silver iodide content. As will be described later, it is surprising that the constitution of the present invention improves both sensitivity, pressure resistance, suitability for rapid processing and the like in the region where the silver iodide content is 0.8 mol% or less.

[0022]

SUMMARY OF THE INVENTION An object of the present invention is to provide a silver halide emulsion composed of tabular silver halide grains excellent in rapid processing suitability and pressure characteristics in view of the above problems. Secondly, to provide a silver halide photographic light-sensitive material excellent in rapid processing suitability and pressure characteristics. Thirdly, to provide a medical silver halide photographic light-sensitive material excellent in rapid processing suitability and pressure characteristics. A fourth object is to provide a method for processing a medical silver halide photographic light-sensitive material excellent in rapid processing suitability and pressure characteristics.

[0023]

The above object of the present invention can be achieved by the following constitutions.

1. 50% or more of the total projected area of silver halide grains contained in the emulsion is tabular silver halide grains having an average aspect ratio of 2 or more and less than 5, and the tabular silver halide grains contain the average silver iodide content. 1. The silver halide photographic emulsion is characterized in that the ratio is 0.8 mol% or less, and silver nuclei are formed inside the tabular silver halide grains. 2. A silver halide photographic light-sensitive material containing the silver halide emulsion described in 1 above. 3. A silver halide photographic light-sensitive material for medical use containing the silver halide emulsion described in 1 above. A method of processing a silver halide photographic light-sensitive material for medical use, which comprises processing the silver halide photographic light-sensitive material described in 3 above for a total processing time of 15 to 90 seconds.

The present invention will be described in more detail below.

In the silver halide emulsion of the present invention, silver bromide, silver iodobromide, silver iodochloride, silver chloroiodobromide, etc. can be used as the silver halide, and particularly silver bromide, iodoodor Silver halide and silver chloroiodobromide are preferred. When using silver iodobromide,
The silver iodide content is 0.8 mol% or less as an average silver iodide content in the entire silver halide grains, but 0.5 mol%
The following is preferable, and 0.4 mol% or less is more preferable.

In the present invention, when the tabular silver halide grains contain silver iodide, the position of inclusion is on the surface and / or inside, but it is preferable to contain it on at least the surface. In the case of the surface, it is particularly preferable to contain it on the outermost surface as described later.

In the present invention, when silver iodide and / or silver chloride is contained, the volume of the pure silver bromide portion is preferably 90% or more of the total volume within the grain. The volume of the pure silver bromide portion means the volume of the portion where substantially no silver iodide and / or silver chloride is detected.

In the present invention, the silver iodide content on the outermost surface of tabular silver halide grains means the XPS method (X-ray Photoe
lectron Spectroscopy: X-ray photoelectron spectroscopy) is the content of silver iodide up to a depth of approximately 50Å.
It can be obtained as follows.

The sample was placed in an ultrahigh vacuum of 1 × 10 ^-8 torr or less-1
Cool down to 10 ℃ or less, and use MgKα as X-ray for the probe.
Irradiate with a source voltage of 15kV and an X-ray source current of 40mA, Ag3d5 / 2, Br3
d, measured for I3d3 / 2 electrons. Correct the integrated intensity of the measured peak with the Sensitivity Factor,
The halide composition of the outermost surface is obtained from these intensity ratios.

The purpose of cooling the sample is to eliminate the measurement error caused by destruction of the sample (decomposition of silver halide and diffusion of halide (particularly iodine)) by irradiation of X-rays at room temperature, and to improve the measurement accuracy. If cooled to -110 ° C, sample destruction can be suppressed to a level that does not hinder measurement.

In the present invention, the silver iodide content and the average silver iodide content of individual silver halide grains are determined by the EPMA method (El
ectron Probe Micro Analyzer method). According to this method, a sample in which emulsion grains are well dispersed so as not to come into contact with each other is prepared, and an X-ray analysis by electron beam excitation and electron beam excitation is performed. By this method, the silver halide composition of each grain can be determined by obtaining the characteristic X-ray intensity of silver and iodide emitted from each grain. When the silver iodide content of at least 50 grains is calculated by the EPMA method, the average silver iodide content (mol%) can be calculated from the average of them.

In the tabular silver halide grain of the present invention, it is preferable that the iodide content of each grain does not vary and the iodide content among grains is more uniform. When the distribution of the iodide content between grains is measured by the EPMA method, the relative standard deviation is preferably 35% or less, more preferably 20% or less.

The silver halide grains contained in the silver halide emulsion of the present invention are tabular silver halide grains. The tabular silver halide grains are grains having two parallel main planes facing each other, and the average value of the ratio of grain size to grain thickness (hereinafter referred to as aspect ratio) (hereinafter referred to as average aspect ratio: Average AR) is greater than 1.3. Here, the grain size means an average projected area diameter (hereinafter referred to as a grain size), which is a circle-equivalent diameter of a projected area of the tabular silver halide grain (of a circle having the same projected area as the silver halide grain). Diameter) and thickness refers to the distance between two parallel major planes forming a tabular silver halide grain.

The tabular silver halide grains contained in the silver halide emulsion of the present invention (hereinafter sometimes abbreviated as tabular silver halide grains of the present invention) are projections of all silver halide grains contained in the emulsion. It occupies 50% or more of the area, and the average aspect ratio is 2 or more and less than 5, but preferably 2.2 or more and less than 5.0. In tabular silver halide grains having an average aspect ratio of 5 or more, or conversely, thick tabular silver halide grains having an average aspect ratio of less than 2.0 or normal crystal grains, silver nuclei are formed inside the grains. However, the effect of improving pressure resistance is not sufficient.

The present invention is characterized in that silver nuclei are formed at any part inside the tabular grains.

The formation of silver nuclei is carried out by adding a reducing agent to the silver halide emulsion or a mixed solution for grain growth. Alternatively, it is carried out by ripening or grain growth of a silver halide emulsion or a mixed solution for grain growth under a low pAg of pH 7 or less or under a high pH condition of pH 7 or more. The method of combining these methods is
This is a preferred embodiment of the present invention.

Preferred reducing agents include thiourea dioxide, ascorbic acid and its derivatives, and stannous salt. Other suitable reducing agents include borane compounds,
Examples thereof include hydrazine derivatives, formamidinesulfinic acid, silane compounds, amines and polyamines, and sulfites. The addition amount is 10 ^-2 per mol of silver halide.
10 ^-8 mol is preferred.

Silver salts can be added for low pAg ripening, but water-soluble silver salts are preferred. Silver nitrate is preferred as the water-soluble silver salt. The pAg during aging is suitably 7 or less, preferably 6 or less, more preferably 1 to 3 (here, pAg = -log [Ag ⁺ ]).

The high pH ripening is carried out, for example, by adding an alkaline compound to a silver halide emulsion or a mixed solution for grain growth. As the alkaline compound, for example, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonia or the like can be used. In the method of adding ammoniacal silver nitrate for silver halide formation, an alkaline compound excluding ammonia is preferably used because the effect of ammonia is reduced.

As a method of adding the silver salt or the alkaline compound for forming the silver nuclei, rush addition may be performed, or addition may be performed over a certain period of time. In this case, the addition may be performed at a constant flow rate, or the flow rate may be changed as a function with respect to time. Also, the required amount may be added in several divided portions. Prior to the addition of the soluble silver salt and / or the soluble halide to the reaction vessel, the soluble silver salt and / or the soluble halide may be present in the reaction vessel, or may be mixed in the soluble halide solution and added together with the halide.
Furthermore, the addition may be performed separately from the soluble silver salt and the soluble halide.

In the preparation of the silver halide emulsion of the present invention, a method of growing from a seed grain is preferably used.
Specifically, it is obtained by preliminarily allowing an aqueous solution containing a protective colloid and seed particles to exist in a reaction vessel, and optionally supplying silver ions, halogen ions, or silver halide fine particles to cause the seed particles to grow crystals. is there. Here, the seed particles can be prepared by a single jet method, a controlled double jet method or the like well known in the art. The halogen composition of the seed grains is arbitrary and may be any of silver bromide, silver iodide, silver chloride, silver iodobromide, silver chloroiodide, silver chlorobromide and silver chloroiodobromide. Silver bromide and silver iodobromide are preferable, and in the case of silver iodobromide, the average silver iodide content is 0.1 to 6
Mol% is preferred.

In the form of crystal growth from seed particles,
The low pAg ripening is preferably performed by adding silver nitrate after the seed emulsion is formed, that is, between the steps immediately before desalting of the seed grains and after desalting. Particularly, it is preferable to add silver nitrate after the desalting of the seed particles for aging, and the aging temperature is 40 ° C or higher, 50
~ 80 ° C is preferred. The aging time is preferably 30 minutes or more and 50 to 150 minutes.

In the form grown from seed particles, high p
When H aging is performed, the volume of the grains after growth is
It is necessary to grow the particles through the environment of pH 7 or more at least once before the portion corresponding to 70% grows, and the pH 7 is reached until the portion corresponding to 50% of the volume of the grown grains grows. It is more preferable to grow the particles through the above environment at least once, and the pH should be adjusted to 8% by the time the portion corresponding to 40% of the volume of the grown particles grows.
It is particularly preferable to grow the particles through the above environment at least once.

An oxidizing agent can be used in the silver halide emulsion of the present invention. The following can be used as the oxidizing agent.

Hydrogen peroxide (water) and its adducts: H ₂ O ₂ ,
_{NaBO 2, H 2 O 2 -3H} 2 O 2, Na 4 P 2 O 7 -2H 2 O 2, 2Na 2 SO 4 -H 2 O 2
−2H ₂ O etc. Peroxy acid salt: K ₂ S ₂ O ₃ , K ₂ C ₂ O ₃ , K ₄ P
₂ O ₃ , K ₂ [Ti (O ₂ ) C ₂ O ₄ ] -3H ₂ O, etc.

Examples thereof include peracetic acid, ozone, iodine, bromine and thiosulfonic acid compounds.

The addition amount of the oxidizing agent used in the present invention is influenced by the type of the reducing agent, the conditions of silver nucleus formation, the timing of addition of the oxidizing agent, and the adding conditions, but it is 10 per 1 mol of the reducing agent used. ^-2 to ^10-5 mol is preferred.

The oxidizing agent may be added at any time during the silver halide emulsion manufacturing process. It can also be added prior to the addition of the reducing agent.

After adding the oxidizing agent, a reducing substance may be newly added in order to neutralize the excess oxidizing agent. These reducing substances are substances capable of reducing the above-mentioned oxidizing agent, sulfinic acids, di- and trihydroxybenzenes, chromanes, hydrazine and hydrazides, p-phenylenediamines, aldehydes, aminophenols, Examples include endiols, oximes, reducing sugars, phenidones, sulfites, and ascorbic acid derivatives. The amount of the reducing substance is preferably an amount per mole ^10-3 to ³ moles of the oxidizing agent to be used is.

The average grain size of the tabular silver halide grains of the present invention is preferably 0.4 to 3.0 μm, more preferably 0.4 to 2.0 μm.

The average thickness of the tabular silver halide grains of the present invention is preferably 0.05 to 1.0 μm, more preferably 0.05 to 0.40 μm, still more preferably 0.05 to 0.30 μm.

The particle size and thickness can be optimized to optimize sensitivity, pressure characteristics and the like. Optimum particle size and optimum thickness depending on other factors (sensitivity of hydrophilic colloid layer, film hardness, chemical ripening condition, sensitivity setting of photosensitive material, silver coating amount, etc.) that compose the photosensitive material that affect sensitivity and pressure characteristics. Different.

The tabular silver halide grains of the present invention are preferably monodisperse emulsions having a narrow grain size distribution, specifically, (standard deviation of grain size / average grain size) × 100 = breadth of grain size distribution (% When the breadth of distribution is defined by), it is preferably 25% or less, more preferably 20% or less, and particularly preferably 15% or less.

The tabular silver halide grains of the present invention preferably have a small thickness distribution. Specifically, (standard deviation of thickness / average thickness) x 100 = 25% or less is preferable when the width of the distribution is defined by the width (%) of the thickness distribution, and more preferably 20% It is as follows, and particularly preferably 15% or less.

The tabular silver halide grains of the present invention are crystallographically classified as twins. Twins are silver halide crystals that have one or more twin planes within a single grain, but the morphology of twins is classified by Klein and Moiser in the article Photographishe Korr
espondenz) 99, 99, 100, 57.

The tabular silver halide grain of the present invention has two or more twin planes parallel to the main plane. The twin plane can be observed with a transmission electron microscope. The specific method is as follows. First, a photosensitive silver halide emulsion is coated so that the main planes of the tabular silver halide grains contained are oriented substantially parallel to the support to prepare a sample. This is cut with a diamond cutter and the thickness is 0.1μ
Obtain thin slices of degree. The presence of twin planes can be confirmed by observing this section with a transmission electron microscope.

In the present invention, the average value of the distance between twin planes is preferably 0.008 μ or more, more preferably
It is 0.010μ or more and 0.05μ or less.

Here, the distance between twin planes means the distance between the twin planes when there are two twin planes, and the distance between the twin planes when there are three or more twin planes. The longest distance.

In the present invention, the average value of the distance between twin planes can be obtained as follows.

That is, by observing the section using the transmission electron microscope, 100 or more tabular silver halide grains having a cross section cut substantially perpendicular to the main plane are arbitrarily selected and each grain is selected. Can be obtained by measuring the distance between twin planes and averaging them.

In the present invention, in the tabular silver halide grains, the outer wall of the crystal may substantially consist of {111} planes or {100} planes. Further, it may have both a {111} plane and a {100} plane. In this case, 50% or more of the grain surface is the {111} plane, more preferably 60 to 99% is the {111} plane,
Particularly preferably, 70 to 95% is the {111} plane. It is preferable that the planes other than the {111} plane are mainly the {100} plane.
This plane ratio is {111} plane and {10} in adsorption of sensitizing dye.
The difference in adsorption dependence with the 0} plane was used [T. Tani, J. Imag
ing Sci., 29, 165 (1985)].

In the present invention, the tabular silver halide grains are preferably hexagonal. A hexagonal tabular grain (hereinafter sometimes referred to as a hexagonal tabular grain) means that its main plane ((111) face) is hexagonal and the maximum adjacency ratio is 1.0 to 2.0. Say Here, the maximum adjacent side ratio is the ratio of the length of the side having the maximum length to the length of the side having the minimum length forming a hexagon. In the present invention, the hexagonal tabular grains have a maximum adjacent side ratio of 1.0 to 2.0.
In that case, it is also preferable that the corners are rounded. The length of a side when the corner is rounded is represented by the distance between the straight line portion of the side and the intersection with the line obtained by extending the straight line portion of the adjacent side. Further, it is also preferable that the tabular grains are more rounded and have a substantially circular shape.

In the present invention, it is preferable that one half or more of each side forming the hexagon of the hexagonal tabular grain is substantially a straight line. In the present invention, the ratio of adjacent sides is 1.0 to 1.5.
Is more preferable.

The silver halide grains of the present invention may have dislocations. The rearrangement is, for example, JF Hamilton, Phot.Sci.Eng,
57 (1967), T.Shiozawa, J.Soc.Phot.Sci.Japan, 35,213
It can be observed by a direct method using a transmission electron microscope at low temperature described in (1972). That is, the silver halide grains taken out carefully so as not to apply pressure enough to cause dislocation to the grains from the emulsion are placed on the mesh for electron microscope observation, and the sample to prevent damage (printout etc.) due to electron beam In the cooled state, observation is performed by the transmission method. At this time, the thicker the particles, the harder it is for the electron beam to pass through. Therefore, for high-pressure particles (particles with a thickness of 0.25 μm, 2
You can observe more clearly using an electron microscope of 00KV or more).

The silver halide emulsion of the present invention is preferably grown by a method of precipitating silver halide on seed grains.

For example, in a method for producing a silver halide photographic emulsion, which is carried out by supplying a water-soluble silver salt solution and a water-soluble halide solution to the presence of a protective colloid to obtain the tabular silver halide emulsion of the present invention. , (A) Silver iodide content of 0
A core particle forming step of maintaining pBr of the mother liquor at 2.5 to -0.7 for a period of 1/2 or more from the initial stage of 5 mol% silver halide precipitation formation is provided. (B) Following the core particle forming step, Providing a seed grain forming step of forming a silver halide seed grain which is substantially monodisperse spherical twin crystals by containing 10 ^{−5 to} 2.0 mol of a silver halide solvent per mol of silver halide, or
Subsequent to the nucleus grain forming step, a seed grain forming step of forming a silver halide twin seed grain by raising the temperature of the mother liquor to 40 to 80 ° C. is provided, and (c) the water-soluble silver salt solution A method of providing a growth step of growing seed grains by adding a functional halide solution and / or silver halide fine grains is preferably used.

Here, the mother liquor is a liquid (including a silver halide emulsion) that is used in the preparation of a silver halide emulsion up to a completed photographic emulsion.

The silver halide grains formed in the core grain forming step are twinned grains composed of 0 to 5 mol% silver iodide.

The seed grain forming step for forming the silver halide seed grains is carried out by the following steps: during precipitation of silver halide, during the Ostwald ripening, pH, pH, temperature, concentration of silver halide solvent, silver halide composition, silver halide and halogen. This is achieved by controlling the addition rate of the chloride solution.

In the preparation of the emulsion of the present invention, a known silver halide solvent such as ammonia, thioether or thiourea can be present during the seed grain forming step and the seed grain growth.

In order to obtain the tabular silver halide grains of the present invention, the conditions for growing the produced seed grains are as follows: JP-A-51-39027, 55-142329, 58-113928, 54
-48521 and 58-49938, the water-soluble silver salt solution and the water-soluble halide solution were added by the double jet method, and the nucleation did not occur depending on the growth rate of the particles. , And the rate at which the size distribution does not spread due to Ostwald ripening, that is, the rate at which new nuclei occur
There is a method of gradually changing it in the range of 100%. Further, as another condition for growing seed grains, a method of growing by adding silver halide fine particles, dissolving and recrystallizing is preferably used, as shown in section 88 of the 1983 Annual Meeting of the Photographic Society of Japan. To be Particularly, silver iodide fine particles, silver bromide fine particles, and silver iodobromide fine particles are preferably used.

The silver halide grains according to the present invention may be so-called halogen conversion type grains. Halogen conversion is 0.2 mol% with respect to silver
The amount of conversion is preferably 0.5 to 0.5 mol%, and the conversion may be carried out during physical aging or after completion of physical aging. As a method for converting halogen, an aqueous solution of halogen or silver halide fine particles having a smaller solubility product with silver than the halogen composition on the surface of the grain before halogen conversion is usually added. The fine particle size at this time is preferably 0.2 μm or less, more preferably 0.02 to 0.1.
μm.

As a method of adjusting the silver iodide content on the outermost surface of the silver halide grains of the present invention, a silver nitrate solution and a solution containing iodo ions are simultaneously added to an emulsion containing tabular grains as a base. The method, the method of adding fine silver halide grains such as silver iodide, silver iodobromide or silver chloroiodobromide, and the addition method of potassium iodide or a mixture of potassium iodide and potassium bromide can be applied. Among these, the method of adding fine silver halide grains is preferable. Especially preferred is the addition of fine silver iodide grains.

The time for adjusting the silver iodide content on the outermost surface is from the final step of the silver halide crystal production step to the chemical ripening step, and further from the completion of the solution preparation step immediately before the coating of the silver halide emulsion. Although it can be selected in the meantime, it is preferable to adjust it by the end of the chemical ripening step. The term "chemical ripening step" as used herein refers to a point from the time when physical ripening and desalting operations of the silver halide emulsion of the present invention are completed, to the time when a chemical sensitizer is added and then the operation for stopping the chemical ripening is performed. Up to. Further, the addition of silver halide fine grains may be carried out several times with a time interval, or another chemically ripened emulsion may be added after the addition of the fine grains. The temperature of the emulsion of the present invention when adding silver halide fine grains is
The range of 30 to 80 ° C is preferable, and the range of 40 to 65 ° C is particularly preferable. Further, the present invention is preferably carried out under the condition that the silver halide fine particles to be added partially or wholly disappear after the addition and immediately before coating. More preferable condition is 20% of the added silver halide fine particles. The above is the disappearance just before coating.

In the production of the silver halide emulsion of the present invention, the stirring conditions during production are extremely important. As the stirring device, the device disclosed in JP-A-62-160128, in which the additive liquid nozzle is installed in the liquid near the mother liquid inlet of the stirrer, is particularly preferably used. At this time, the stirring speed is 100 to 120.
It is preferably 0 rpm.

The details of the above-mentioned supersaturation factor are as follows.
For example, the description in JP-A-63-92942 or JP-A-1-213637 can be referred to.

The silver halide grains contained in the silver halide emulsion of the present invention include a cadmium salt, a zinc salt, a lead salt, a thallium salt and an iridium salt (including a complex salt) in the process of forming and / or growing the grains. ), A rhodium salt (including a complex salt), and an iron salt (including a complex salt), at least one metal ion is added to allow the metal element to be contained inside and / or on the surface of the particle. it can.

In the present invention, it is also preferable to add a silver halide solvent before the desalting step in order to accelerate the developing rate. For example, a thiocyanate compound (potassium thiocyanate, sodium thiocyanate, ammonium thiocyanate, etc.) is preferably added in an amount of 1 × 10 ^{−3 to} 3 × 10 ⁻² mol per mol of silver.

In the present invention, it is preferable to use gelatin as the dispersion medium for the protective colloid of silver halide grains, and as the gelatin, alkali-treated gelatin, acid-treated gelatin, low molecular weight gelatin (molecular weight of 20,000 to 100,000),
Modified gelatin such as phthalated gelatin is used. Other hydrophilic colloids can also be used. Specifically, Research Disclosu
re, hereinafter abbreviated as RD) Volume 176, No. 17643 (December 1978) IX
The items described in the section are included.

The silver halide emulsion of the present invention may remove unnecessary soluble salts during the growth of silver halide grains,
Alternatively, it may remain contained. The removal of the salts can be carried out according to the method described in Item II of RD Vol. 176, No. 17643.

The silver halide emulsion of the present invention can be chemically sensitized.

There are no particular restrictions on the conditions of the chemical ripening, that is, the steps of chemical sensitization, such as pH, pAg, temperature and time, and the conditions generally used in the art can be used. For chemical sensitization, a sulfur sensitization method using a compound containing sulfur capable of reacting with silver ions or active gelatin, a selenium sensitization method using a selenium compound, a tellurium sensitization method using a tellurium compound, or a reducing substance is used. The reduction sensitization method to be used, gold or other, and a noble metal sensitization method using a noble metal can be used alone or in combination. Among them, the selenium sensitization method, the tellurium sensitization method, the reduction sensitization method and the like are preferably used. ,
Particularly, the selenium sensitization method is preferably used.

In the case of selenium sensitization, the selenium sensitizers used include a wide variety of selenium compounds. For example, in this regard, U.S. Pat.Nos. 1,574,944, 1,602,592, 1,62.
3,499, JP 60-150046, JP 4-25832, 4-1
09240, 4-147250, etc. Useful selenium sensitizers include colloidal selenium metal, isoselenocyanates (eg, allyl isoselenocyanate), selenoureas (eg, N, N-dimethylselenourea, N, N, N′-triethylselenoate). Urea, N, N, N′-trimethyl-N′-heptafluoroselenourea, N, N, N′-trimethyl-N′-heptafluoropropylcarbonylselenourea, N, N, N′-trimethyl-N′- 4-nitrophenylcarbonyl selenourea etc.), selenoketones (eg selenoacetone, selenoacetophenone etc.), selenoamides (eg selenoacetamide, N, N-dimethylselenobenzamide etc.), selenocarboxylic acids and selenoesters (eg , 2-selenopropionic acid, methyl-3-selenobutylate, etc.), selenophosphates (eg,
Tri-p-triselenophosphate and the like) and selenides (triphenylphosphine selenide, diethyl selenide, diethyl diselenide and the like). Particularly preferred selenium sensitizers are selenoureas, selenoamides and selenium ketones, and selenides.

Specific examples of techniques for using these selenium sensitizers are disclosed in the following patents. U.S. Pat.No. 1,574,944
No. 1, No. 1,602,592, No. 1,623,499, No. 3,297,446
Issue 3,297,447, 3,320,069, 3,408,196,
3,408,197, 3,442,653, 3,420,670, 3,5
91,385, French Patents 2,693,038, 2,093,209
No. 52-34491, 52-34492, 53-295, 53-295
57-22090, JP-A-59-180536, 59-185330, 59
-181337, 59-187338, 59-192241, 60-1500
46, 60-151637, 61-246738, JP 3-4221
No. 3, No. 3-24537, No. 3-111838, No. 3-116132, No. 3-1
48648, 3-237450, 4-16838, 4-25832,
4-32831, 4-96059, 4-109240, 4-140738
No. 4-140739, 4-147250, 4-149437, 4-
184331, 4-190225, 4-191729, 4-195035
No., British Patent Nos. 255,846, 861,984, etc. In addition, HESpen
cer et al., Journal of Photographic Science magazine, Vol. 31, 15
It is also disclosed in scientific literature such as pages 8 to 169 (1983).

The amount of the selenium sensitizer used varies depending on the selenium compound used, silver halide grains, chemical ripening conditions and the like, but generally about 10 ^-8 to 10 ^-4 mol per mol of silver halide is used. The addition method is, depending on the properties of the selenium compound to be used, a method in which water or an organic solvent such as methanol or ethanol is dissolved alone or in a mixed solvent, or a method in which the solution is added in advance by mixing with a gelatin solution. However, the method disclosed in JP-A-4-140739, that is, the method of adding in the form of an emulsion dispersion of a mixed solution with a polymer soluble in an organic solvent may be used.

The temperature of the chemical ripening using the selenium sensitizer is
The range of 40 to 90 ° C is preferable. More preferably 45 ° C or higher
It is below 80 ℃. The pH is preferably in the range of 4 to 9 and the pAg is preferably in the range of 6 to 9.5.

Tellurium sensitizers and sensitizing methods are described in US Pat. Nos. 1,623,499, 3,320,069, and 3,772,031,
No. 3,531,289, No. 3,655,394, British Patent No. 235,211
Issue 1,121,496, Issue 1,295,462, Issue 1,396,696,
Canadian Patent No. 800,958, JP-A-4-204640, and 4-33304
No. 3 etc. Examples of useful tellurium sensitizers include telluroureas (e.g., N, N-dimethyl tellurourea, tetramethyl tellurourea, N-carboxyethyl-N,
N'-dimethyl tellurourea, N, N'-dimethyl-N'phenyl tellurourea), phosphine tellurides (eg, tributylphosphine telluride, tricyclohexylphosphine telluride, triisopropylphosphine telluride, butyl-diisopropylphosphine telluride) Lido, dibutylphenylphosphine telluride), telluroamides (for example, telluroacetamide, N, N-dimethyl tellurobenzamide), telluroketones, telluroesters, and isotellurocyanates.

The technique for using the tellurium sensitizer is similar to that for the selenium sensitizer.

It is also preferable to carry out so-called reduction sensitization on the surface of the grain by placing it in an appropriate reducing atmosphere.

Preferred examples of the reducing agent include thiourea dioxide and ascorbic acid and their derivatives. Other preferable reducing agents include hydrazine, polyamines such as diethylenetriamine, dimethylamineboranes, sulfites and the like.

The amount of the reducing agent added is determined by the type of reduction sensitizer, the grain size of the silver halide grains, the composition and crystal habit, the temperature of the reaction system,
Although it is preferable to change the pH depending on the environmental conditions such as pH and pAg, for example, in the case of thiourea dioxide, as a rough guide, use of about 0.01 to 2 mg per mol of silver halide gives favorable results. In the case of ascorbic acid, a range of about 50 mg to 2 g is preferable per mol of silver halide.

As the conditions for reduction sensitization, the temperature is about 40 to 70.
C, time about 10-200 minutes, pH about 5-11, pAg about 1-1
A range of 0 is preferred (where the pAg value is the reciprocal of the Ag ⁺ ion concentration).

The water-soluble silver salt is preferably silver nitrate.
By adding a water-soluble silver salt, so-called silver ripening, which is a kind of reduction sensitization technique, is performed. The pAg during silver ripening is suitably 1-6, preferably 2-4. The conditions such as temperature, pH and time are preferably within the above-mentioned reduction sensitization condition range. As a stabilizer of a silver halide photographic emulsion containing reduction-sensitized silver halide grains, a general stabilizer described below can be used, but it is disclosed in JP-A-57-82831. Antioxidants and / or papers by VS Gahler [Zeitshrift fur wissenschaftliche Photographie B
d.63, 133 (1969)] and thiosulfonic acids described in JP-A-54-1019 are often used together with good results. The addition of these compounds may be carried out at any stage of the emulsion production process from crystal growth to the preparation process immediately before coating.

The silver halide photographic light-sensitive material of the present invention is a silver halide photographic light-sensitive material containing the above-described silver halide emulsion of the present invention, and for example, a black-and-white silver halide photographic light-sensitive material (for example, medical light-sensitive material). Materials, photosensitive materials for printing, negative photosensitive materials for general photography, etc., color photographic photosensitive materials (for example, color negative photosensitive materials, color reversal photosensitive materials,
Photosensitive materials for color printing, etc.), photosensitive materials for diffusion transfer,
Although it is a photothermographic material or the like, it is preferably a black-and-white silver halide photographic light-sensitive material, and particularly preferably a medical light-sensitive material.

The processing method of the medical silver halide photographic light-sensitive material of the present invention is the same as that of the medical silver halide photographic light-sensitive material containing the silver halide photographic emulsion of the present invention.
It is a processing method that processes from 90 seconds to 90 seconds.

The silver halide emulsion of the present invention may contain a developing agent such as aminophenol, ascorbic acid, pyrocatechol, hydroquinone, phenylenediamine or 3-pyrazolidone in the emulsion layer or a layer having other layers.

The hydrophilic colloid of the silver halide emulsion layer and the non-photosensitive layer of the light-sensitive material of the present invention preferably contains an inorganic or organic hardener. For example, chromium salts (chromium alum, chromium acetate, etc.), aldehydes (formaldehyde, glyoxal, glutaraldehyde, etc.), N-methylol compounds (dimethylolurea, methyloldimethylhydantoin, etc.), dioxane derivatives (2,3-dihydroxydioxane, etc.) ), An active vinyl compound (1,3,5-triacryloyl-hexahydro-s-
Triazine, bis (vinylsulfonyl) methyl ether,
N, N'-methylenebis (β- (vinylsulfonyl) propionamide), active halogen compounds (2,4-dichloro-6-hydroxy-s-triazine, etc.), mucohalogen acids (mucochloric acid, mucophenoxycycloric acid, etc.) ), Isoxazoles, 2-chloro-6-hydroxytriazinylated gelatin and the like can be used alone or in combination. Among them, JP-A-53-41221, JP-A-53-57257,
The active vinyl compounds described in 59-162456 and 60-80846 and the active halogen compounds described in US Pat. No. 3,325,287 are preferable.

As the hardener of the present invention, a polymeric hardener can be effectively used. For example, dialdehyde starch, polyacrolein, a polymer having an aldehyde group such as acrolein copolymer described in U.S. Patent No. 3,396,029, a polymer having an epoxy group described in U.S. Patent No. 3,623,878,
US Pat. No. 3,362,827, polymers having a dichlorotriazine group described in Research Disclosure Magazine 17333 (1978), polymers having an active ester group described in JP-A-56-66841, JP-A-56 -142
Polymers having an active vinyl group described in, for example, 524, U.S. Pat.No. 4,161,407, JP-A-54-65033, Research Disclosure 16725 (1978), or a group serving as a precursor thereof are preferable, and among them, A polymer in which an active vinyl group or a group serving as a precursor thereof is bonded to a polymer main chain by a long spacer as described in JP-A-56-142524 is particularly preferable.

In order to make the photographic light-sensitive material of the present invention suitable for rapid processing, an appropriate amount of a hardener is added in advance in the coating step of the light-sensitive material to improve the water swelling rate in the developing-fixing-water washing step. It is preferable to adjust the water content in the light-sensitive material before the start of drying.

The silver halide light-sensitive material of the present invention preferably has a swelling ratio during development of 150 to 250% and a film thickness after expansion of 70 μm or less. If the water swelling rate exceeds 250%, poor drying occurs, and, for example, poor handling occurs in automatic processor processing, especially rapid processing. Also, the water swelling rate is 150%
If it is less than the range, uneven development and residual color tend to be deteriorated upon development. Here, the water swelling rate means the difference between the film thickness after swelling in each processing solution and the film thickness before the development processing, which is divided by the film thickness before processing and multiplied by 100. .

Examples of the support that can be used in the light-sensitive material of the present invention include the above-mentioned RD-17643, page 28 and RD.
-308119, page 1009.

A suitable support is a plastic film or the like, and the surface of these supports may be provided with an undercoat layer, corona discharge, ultraviolet irradiation or the like in order to improve the adhesion of the coating layer.

In the silver halide photographic light-sensitive material of the present invention, various additives can be added to the silver halide emulsion according to the purpose. Examples of additives and the like used include Research Disclosure (RD) No. 1
7643 (December 1978), No.18716 (November 1979) and No.3
Examples are those described in 08119 (December 1989). The places where they are written are listed below.

Additive RD-17643 RD-18716 RD-308119 Page Classification Page Classification Page Classification Chemical sensitizer 23 III 648 Upper right 996 III Sensitizing dye 23 IV 648-649 996-8 IV Desensitizing dye 23 IV 998 IV Dye 25-26 VIII 649-650 1003 VIII Development accelerator 29 XXI 648 Upper right fog inhibitor / stabilizer 24 IV 649 Upper right 1006-7 VI Whitening agent 24 V 998 V Hardener 26 X 651 Left 1004-5 X Surfactant Agent 26-7 XI 650 Right 1005-6 XI Antistatic agent 27 XII 650 Right 1006-7 XIII Plasticizer 27 XII 650 Right 1006 XII Sliding agent 27 XII Matting agent 28 XVI 650 Right 1008-9 XVI Binder 26 XXII 1003-4 IX Support 28 XVII 1009 XVII Next, preferable development processing of the light-sensitive material of the present invention will be described.

Preferred developing solutions for developing the light-sensitive material of the present invention include developing agents such as JP-A-4-15641 and JP-A-4.
-16841 and the like dihydroxybenzene, such as hydroquinone, para-aminophenols, such as p-aminophenol, N-methyl-p-aminophenol, 2,4-diamiphenol, 3-pyrazolidones, for example, 1 -Phenyl-3-pyrazolidones, 1-phenyl-3-pyrazolidone, 1-phenyl-4-methyl-4-hydroxymethyl-3-
Pyrazolidone, 5,5-dimethyl-1-phenyl-3-pyrazolidone and the like are preferably used in combination.

The amount of the paraaminophenols and 3-aminopyrazolidones used is preferably 0.004 mol / liter, more preferably 0.04 to 0.12 mol / liter.

Further, the total number of moles of dihydroxybenzenes, paraaminophenols and 3-pyrazolidones contained in the components of all the developing solutions is preferably 0.1 mol / liter or less.

Preservatives may include sulfites such as potassium sulfite, sodium sulfite, reductones such as piperidinohexose reductone,
These are preferably used in an amount of 0.2 to 1 mol / liter, more preferably 0.3 to 0.6 mol / liter. Further, addition of a large amount of ascorbic acid also leads to processing stability.

As the alkaline agent, sodium hydroxide,
Includes pH regulators such as potassium hydroxide, sodium carbonate, potassium carbonate, sodium triphosphate, potassium triphosphate. Further, borate described in JP-A-61-28708, JP-A-60-
Buffers such as saccharose, acetoxime, 5-sulfosalicylic acid, phosphates and carbonates described in No. 93439 may be used. The content of these agents is such that the pH of the developer is 9.0 to 13,
The pH is preferably selected to be 10 to 12.5.

As the solubilizing agent, polyethylene glycols and their esters, and as the sensitizing agent,
For example, a development accelerator, a surfactant, etc. such as a quaternary ammonium salt can be contained.

As a silver sludge preventive agent, JP-A-56-106 has been used.
Silver antifouling agents described in No. 244, sulfides and disulfide compounds described in JP-A-3-51844, and cysteine derivatives or triazine compounds described in Japanese Patent Application No. 4-92947 are preferably used.

As the organic inhibitor, an azole type organic antifoggant, for example, an indazole type, an imidazole type, a benzimidazole type, a triazole type, a benztriazole type, a tetrazole type or a thiadiazole type compound is used.

Examples of the inorganic inhibitor include sodium bromide, potassium bromide, potassium iodide and the like. Besides this, L.
FA Menson, "Photographic Processing Chemistry," 22, published by Focal Press, Inc. (1966)
Those described in pages 6 to 229, US Pat. Nos. 2,193,015, 2,592,364, and JP-A-48-64933 may be used. As a chelating agent for masking calcium ions mixed in tap water used in the treatment liquid, a chelating agent having a chelate stabilization constant of 8 or more with iron described in JP-A 1-193853 is preferably used as an organic chelating agent. To be Examples of the inorganic chelating agent include sodium hexametaphosphate, calcium hexametaphosphate, and polyphosphate.

As the development hardening agent, a dialdehyde compound may be used. In this case, glutaraldehyde is preferably used. However, for rapid processing, it is preferable that the hardener is allowed to act in the coating step of the photosensitive material in advance as described above, rather than the hardener is allowed to act in the development processing step.

The processing temperature of the developer of the present invention is preferably
The temperature is 25 to 50 ° C, more preferably 30 to 40 ° C. The development time is 3 to 90 seconds, more preferably 5 to 60 seconds. The treatment time is Dry to Dry, preferably 10 to 210 seconds, more preferably 15 to 90 seconds.

The replenishment in the present invention replenishes the treatment agent fatigue and oxidative fatigue. As a replenishment method, JP-A-55-126
Replenishment according to width and feed rate described in Japanese Patent No. 243, JP-A-60-1049
Area replenishment described in No. 46 or area replenishment controlled by the number of continuously processed sheets described in JP-A-1-149156 may be used, and a preferable replenishment rate is 500 to 150 ml / m ² .

Preferred fixing solutions can include fixing materials commonly used in the art. The pH is 3.8 or more, preferably 4.2 to 5.5.

As a fixing agent, ammonium thiosulfate,
It is a thiosulfate such as sodium thiosulfate, and ammonium thiosulfate is particularly preferable in terms of fixing speed. The concentration of ammonium thiosulfate is preferably in the range of 0.1 to 5 mol / l, more preferably 0.8 to 3 mol / l.

The fixing solution of the present invention may be one which performs acidic hardening. In this case, aluminum ions are preferably used as the hardener. For example, it is preferably added in the form of aluminum sulfate, aluminum chloride, potassium alum, or the like.

Others In the fixing solution of the present invention, if desired, a preservative such as sulfite or bisulfite, a pH buffering agent such as acetic acid or boric acid, a mineral acid (sulfuric acid, nitric acid) or an organic acid (citric acid, oxalic acid). ,
(Eg, malic acid), various acids such as hydrochloric acid, pH adjusting agents such as metal hydroxides (potassium hydroxide, sodium hydroxide), and chelating agents having a water softening ability.

As the fixing accelerator, for example, JP-B-45-357.
No. 54, No. 58-122535, No. 58-122536 and the like, and thioethers described in US Pat. No. 4,126,459.

When the present invention is applied to medical X-ray radiography, for example, a fluorescent intensifying screen whose main component is a phosphor which emits near-ultraviolet light or visible light upon exposure to penetrating radiation is used. It is desirable that the emulsion is adhered to both sides of a light-sensitive material prepared by coating the emulsion of the present invention on both sides and exposed.

The penetrating radiation mentioned here is an electromagnetic wave of high energy and means X-rays and gamma rays.

The fluorescent intensifying screen refers to, for example, an intensifying screen mainly containing calcium tungstate as a fluorescent component or a fluorescent intensifying screen mainly containing a terbium-activated rare earth compound. As the fluorescent intensifying screen, a fluorescent component uniformly coated on a support or a cylindrical or conical coating can be used. German Karm an Karlsruhe presented at Session 868C of the '92 RSNA (Radiological Society of America) when using particularly low-sensitivity light-sensitive materials.
Like the nuclear reserch microstructure intensifying screen, by increasing the thickness of the fluorescent component and applying it in a conical shape, the sensitivity of the intensifying screen is increased and at the same time the quantum mottle is reduced to improve graininess. Is preferably used.

[0126]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited thereto.

Example 1 (Preparation of seed emulsion) Seed emulsion-1 was prepared as follows.

A1 ossein gelatin 24.2 g water 9657 ml polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt (10% ethanol aqueous solution) 6.78 ml potassium bromide 10.8 g 10% nitric acid 114 ml B1 2.5 N silver nitrate aqueous solution 2825 ml C1 potassium bromide 841 g 2825 ml of D1 1.75N aqueous solution of potassium bromide in water Solution A1 and solution C1 are mixed into solution A1 using the mixing stirrer shown in JP-B-58-58288 and 58-58289 at the following silver potential control amount of 42 ° C.
Nucleation was performed by adding 464.3 ml by the double-sided mixing method over 1.5 minutes.

After stopping the addition of solution B1 and solution C1, it took 60 minutes to raise the temperature of solution A1 to 60 ° C., adjust the pH to 5.0 with 3% KOH, and then add solution B1 again. Solution C1 was added by the double jet method at a flow rate of 55.4 ml / min each for 42 minutes. The silver potential (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) during this temperature increase from 42 ° C. to 60 ° C. and re-simultaneous mixing with the solutions B1 and C1 was +8 mv using the solution D1. And was controlled to be +16 mv.

After the addition was completed, the pH was adjusted to 6 with 3% KOH, and desalting and washing with water were immediately performed. This seed emulsion has a maximum adjacent side ratio of 1.0 to 90% of the total projected area of silver halide grains.
It was confirmed by an electron microscope that the hexagonal tabular grains had an average thickness of 0.064 μm and an average grain size (circular diameter conversion) of 0.595 μm. The coefficient of variation of thickness is
The coefficient of variation of the distance between twin planes was 40% and 42%.

Seed emulsion-2 was prepared as follows.

That is, desalting was carried out in the same manner as in the seed emulsion-1.
After washing with water, the mixture was vigorously stirred while maintaining the temperature at 60 ° C. in the reaction vessel, the whole amount of the solution E1 was added thereto, and the mixture was stagnated for 80 minutes. Then, the whole amount of the solution F1 was added into the reaction vessel.

E1 Silver nitrate 20.64 g Finish with water to 129.81 l F1 Potassium bromide 14.46 g Finish with water to 192.84 l Preparation of Em-1 Using tabular emulsion-1 and the following three solutions, tabular pure bromide A silver emulsion Em-1 was prepared.

A2 ossein gelatin 34.03g polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt (10% ethanol aqueous solution) 2.25ml seed emulsion-1 1.218mol equivalent water to make 3150ml B2 potassium bromide 1747g water to make 3669ml C2 Silver nitrate 2493 g Finished to 4193 ml with water Solution A2 was vigorously stirred in a reaction vessel while maintaining it at 60 ° C., and the total amount of solution B2 and solution C2 was added thereto by the simultaneous mixing method over 100 minutes. During this time, pH was 5.8 and pAg was 8.8.
Kept from beginning to end. Here, the addition rates of the solution B2 and the solution C2 were changed in a function-like manner with respect to time so as to be commensurate with the critical growth rate. That is, the addition was performed at an appropriate addition rate so that small particles were not generated other than the growing seed particles and polydispersion did not occur due to Ostwald ripening.

After completion of the addition, this emulsion was cooled to 40 ° C., and a 13.8% (by weight) aqueous solution of modified gelatin modified with a phenylcarbamoyl group as a coagulating polymer agent (substitution rate 90%) 1800
ml was added and stirred for 3 minutes. Then, a 56% (weight) acetic acid aqueous solution was added to adjust the pH of the emulsion to 4.6, the mixture was stirred for 3 minutes, allowed to stand for 20 minutes, and the supernatant was drained by decantation. Then, 9.0 l of distilled water at 40 ° C was added, the mixture was left to stir, and the supernatant liquid was drained off.
1 was added, the mixture was left standing with stirring, and the supernatant was drained. continue,
A gelatin aqueous solution and a 10% (weight) sodium carbonate aqueous solution were added to adjust the pH to 5.80, and the mixture was stirred at 50 ° C. for 30 minutes and redispersed. After redispersion, pH is 5.80 at 40 ℃, pAg
Was adjusted to 8.06.

Subsequently, after the emulsion was heated to 60 ° C., a predetermined amount of the spectral sensitizing dyes A and B was added as a solid fine particle dispersion, and then a mixed aqueous solution of ammonium thiocyanate, chloroauric acid and sodium thiosulfate and A methanol solution of N, N'-dimethylselenourea was added, and the mixture was aged for a total of 2 hours. At the end of the ripening, an appropriate amount of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene (TAI) was added as a stabilizer.

[0137]

Embedded image

Additives other than the spectral sensitizing dye and the addition amount (per 1 mol of AgX) are shown below.

Ammonium thiocyanate 95 mg Chloroauric acid 2.5 mg Sodium thiosulfate 2.0 mg Triphenylphosphine selenide 0.4 mg Stabilizer (TAI) 1000 mg Solid fine particle dispersion of spectral sensitizing dye is disclosed in Japanese Patent Application No. 4-99437. Prepared by a method similar to the method described.

That is, a predetermined amount of the spectral sensitizing dye was added to water whose temperature had been adjusted to 27 ° C. in advance, and a high-speed stirrer (dissolver) was operated at 3.500 rpm.
It was obtained by stirring at 30-120 min.

When the obtained silver halide emulsion was observed with an electron microscope, tabular silver halide grains having an average grain size of 1.11 μ, an average thickness of 0.25 μ, an average aspect ratio of about 4.5 and a grain size distribution of 18.1% were obtained. Met. Also, the average distance between twin planes is
It was 0.020μ.

Preparation of Em-2 Em-2 was prepared by changing the following points from the preparation of Em-1.

That is, in the preparation of Em-1, the solution A2
The pH of the solution is adjusted to 9.0, and 1/2 amount of the solutions B2 and C2 is added thereto, and then the pH is adjusted to 5.8, and the remaining 1/2 of the solutions B2 and C2 is added.
Amount was added.

Preparation of Em-3 Tabular silver halide emulsion Em-3 having an average silver iodide content of 0.4 mol% was prepared using seed emulsion-1 and the following four kinds of solutions.

A3 ossein gelatin 34.03g polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt (10% ethanol aqueous solution) 2.25ml seed emulsion-1 1.218 moles equivalent water finish 3150ml B3 potassium bromide 1742g water finish 3659ml C3 Silver nitrate 2486g Finish to 4182ml with water D3 3wt% gelatin and silver iodide grains (average grain size 0.05μ) Fine grain emulsion (*) Equivalent to 0.039mol *: 5.0wt% containing 0.06mol potassium iodide To 6.64 liters of the gelatin aqueous solution of 1), 2 liters of an aqueous solution containing 7.06 mol of silver nitrate and 7.06 mol of potassium iodide, respectively,
Added over 0 minutes. The pH during fine particle formation was controlled to 2.0 using nitric acid, and the temperature was controlled to 40 ° C. After particle formation, the pH was adjusted to 6.0 using an aqueous sodium carbonate solution.

Solution A3 was vigorously stirred in the reaction vessel while being kept at 60 ° C., and a part of solution B3, a part of solution C3 and a total amount of solution D3 were added thereto by a simultaneous mixing method over 16 minutes, After that, the remaining amounts of the solution B3 and the solution C3 were added by the simultaneous mixing method over 39 minutes. During this time, pH was 5.8 and pA
g kept at 8.8 throughout. Here, the addition rates of the solution B3 and the solution C3 were changed in a function-like manner with respect to time so as to match the critical growth rate. That is, the addition was performed at an appropriate addition rate so that small particles were not generated other than the growing seed particles and polydispersion did not occur due to Ostwald ripening. The rate of addition of the solution D3 was 0.
I kept it at 06.

Further, the above solution D3 was added in an amount of 0.15 with respect to the total amount of silver.
Halogen substitution was carried out by adding mol% equivalent.

After the completion of the addition, insoluble salts were removed in the same manner as Em-1. Subsequently, spectral sensitization and chemical sensitization were performed in exactly the same manner as Em-1.

When the obtained silver halide emulsion was observed with an electron microscope, tabular silver halide grains having an average grain size of 1.04μ, an average thickness of 0.26μ, an average aspect ratio of about 4.0 and a grain size distribution of 19.0% were obtained. Met.

Preparation of Em-4 Em-4 was prepared in exactly the same manner as Em-3 except that seed emulsion-1 was changed to seed emulsion-2 in the preparation of Em-3.

Preparation of Em-5 Em-5 was prepared by changing the following points from the preparation of Em-3.

That is, in the preparation of Em-3, the solution A3
The pH of the solution was adjusted to 9.0, and 1/2 of the solutions B3 and C3 was added to it, and then the pH was adjusted to 5.8, and the remaining 1/2 of the solutions B3 and C3 was added.
Amount was added.

Preparation of Em-6 Em-6 was prepared by changing the following points from the preparation of Em-3.

That is, Em-6 was prepared in the same manner as Em-3 except that the solution G1 shown below was rushed into the reaction vessel 2 minutes after the addition of the solutions B3 and C3 to the solution A3.

G1 Thiourea dioxide 0.035 g Finish with water to 32.5 ml Preparation of Em-7 Using seed emulsion-1 and the following four solutions, a tabular silver halide emulsion having an average silver iodide content of 0.15 mol% Em-7 was prepared.

A4 ossein gelatin 34.03 g Polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt (10% ethanol aqueous solution) 2.25 ml Seed emulsion-1 1.218 mol equivalent Water to make 3150 ml B4 potassium bromide 1747 g Water to make 3669 ml C4 Silver nitrate 2493g Finish to 4193ml with water D4 3wt% gelatin and silver iodide grains (average grain size 0.05μ) Fine grain emulsion (*) *: 5.0wt% gelatin aqueous solution containing 0.06mol potassium iodide To 6.64 liters, 2 liters of an aqueous solution each containing 7.06 mol of silver nitrate and 7.06 mol of potassium iodide,
Added over 10 minutes. The pH during fine particle formation was controlled to 2.0 using nitric acid, and the temperature was controlled to 40 ° C. After particle formation, the pH was adjusted to 6.0 using an aqueous sodium carbonate solution.

Solution A4 was stirred vigorously in the reaction vessel while maintaining it at 60 ° C., and the total amount of solution B4 and solution C4 was adjusted to 100.
It was added by the double-sided mixing method over minutes. During this time, the pH is 5.8
In addition, pAg was kept at 8.8 throughout. Here, solution B4 and solution C
The addition rate of 4 was changed function-wise with respect to time so as to be commensurate with the critical growth rate. That is, the addition was performed at an appropriate addition rate so that small particles were not generated other than the growing seed particles and polydispersion did not occur due to Ostwald ripening.

Further, the above solution D4 was added in an amount of 0.15 with respect to the total amount of silver.
Halogen substitution was carried out by adding mol% equivalent.

After completion of the addition, insoluble salts were removed in the same manner as Em-1. Subsequently, spectral sensitization and chemical sensitization were performed in exactly the same manner as Em-1.

When the obtained silver halide emulsion was observed with an electron microscope, tabular silver halide grains having an average grain size of 1.11 μ, an average thickness of 0.25 μ, an average aspect ratio of about 4.5 and a grain size distribution of 18.1% were obtained. Met. Also, the average distance between twin planes is
It was 0.020μ.

Preparation of Em-8 Em-8 was prepared by changing the following points from the preparation of Em-7.

That is, in the preparation of Em-7, the solution A4
The pH of the solution was adjusted to 9.0, and 1/2 of the solutions B4 and C4 was added to it, and then the pH was adjusted to 5.8, and the remaining 1/2 of the solutions B4 and C4 was added.
Amount was added.

Preparation of Em-9 A tabular silver halide emulsion Em-9 having an average silver iodide content of 0.7 mol% was prepared using seed emulsion-1 and the following four kinds of solutions.

A5 ossein gelatin 34.03g polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt (10% aqueous ethanol solution) 2.25ml seed emulsion-1 1.218mol equivalent water to make 3150ml B5 potassium bromide 1739g water to make 3653ml C5 Silver nitrate 2482g Finish to 4175ml with water D5 3wt% gelatin and silver iodide grains (average grain size 0.05μ) Fine grain emulsion (*) Equivalent to 0.064mol *: 5.0wt% containing 0.06mol potassium iodide To 6.64 liters of the above gelatin aqueous solution, 2 liters each of 7.06 mol of silver nitrate and 7.06 mol of potassium iodide are added.
Added over 10 minutes. The pH during fine particle formation was controlled to 2.0 using nitric acid, and the temperature was controlled to 40 ° C. After particle formation, the pH was adjusted to 6.0 using an aqueous sodium carbonate solution.

Solution A5 was vigorously stirred in the reaction vessel while keeping it at 60 ° C., and a part of solution B5, a part of solution C5 and a total amount of solution D5 were added thereto by a simultaneous mixing method over 17 minutes, After that, the remaining amounts of the solution B5 and the solution C5 were successively added over 52 minutes by the simultaneous mixing method. During this time, pH was 5.8 and pA
g kept at 8.8 throughout. Here, the addition rates of the solution B5 and the solution C5 were changed in a function-like manner with respect to time so as to match the critical growth rate. That is, the addition was performed at an appropriate addition rate so that small particles were not generated other than the growing seed particles and polydispersion did not occur due to Ostwald ripening. The addition rate of the solution D5 was 0.06 when the rate ratio (molar ratio) with the solution C5 was set to 0.06.
Kept at.

Further, the above solution D5 was added to 0.30 with respect to the total silver amount.
Halogen substitution was carried out by adding mol% equivalent.

After completion of the addition, insoluble salts were removed in the same manner as Em-1. Subsequently, spectral sensitization and chemical sensitization were performed in exactly the same manner as Em-1.

When the obtained silver halide emulsion was observed with an electron microscope, tabular silver halide grains having an average grain size of 1.04μ, an average thickness of 0.26μ, an average aspect ratio of about 4.0 and a grain size distribution of 18.5% were obtained. Met. Also, the average distance between twin planes is
0.020μ, 97% (number) of all tabular silver halide grains with a ratio of twin plane distance to thickness of 5 or more, 49% with 10 or more grains, 17% with 15 or more grains Was occupied.

Preparation of Em-10 Em-10 was prepared by changing the following points from the preparation of Em-9.

That is, in the preparation of Em-9, the solution A5
The pH of the solution is adjusted to 9.0, and 1/2 amount of the solutions B5 and C5 is added thereto, and then the pH is adjusted to 5.8, and the remaining 1/2 of the solutions B5 and C5 is added.
Amount was added.

Preparation of Em-11 Em-11 was prepared by changing the following points from the preparation of Em-9.

That is, the solution A5 was vigorously stirred in the reaction vessel while being kept at 60 ° C., and a part of the solution B5 and the solution C5 were stirred therein.
Part of the solution and the total amount of the solution D5 were added by the simultaneous mixing method over 20 minutes, and then the remaining amount of the solution B5 and the solution C5 was 60%.
It was added by the double-sided mixing method over minutes. During this time, the pH is 5.8
In addition, pAg was kept at 8.5 throughout. Here, the addition rates of the solution B5 and the solution C5 were changed in a function-like manner with respect to time so as to match the critical growth rate. That is, the addition was performed at an appropriate addition rate so that small particles were not generated other than the growing seed particles and polydispersion did not occur due to Ostwald ripening. Regarding the addition rate of the solution D5, the rate ratio (molar ratio) with the solution C5 was maintained at 0.06.

Preparation of Em-12 Em-12 was prepared by changing the following points from the preparation of Em-11.

That is, in the preparation of Em-11, solution A5
The pH of the solution is adjusted to 9.0, and 1/2 amount of the solutions B5 and C5 is added thereto, and then the pH is adjusted to 5.8, and the remaining 1/2 of the solutions B5 and C5 is added.
Amount was added.

Preparation of Em-13 Em-13 was prepared by changing the following points from the preparation of Em-9.

That is, the solution A5 was vigorously stirred in the reaction vessel while being kept at 60 ° C., and a part of the solution B5 and the solution C5 were stirred therein.
Part of the solution and the total amount of the solution D5 were added by the simultaneous mixing method over 14 minutes, and then the remaining amount of the solution B5 and the solution C5 was 44%.
It was added by the double-sided mixing method over minutes. During this time, the pH is 5.8
In addition, pAg was kept at 9.1 throughout. Here, the addition rates of the solution B5 and the solution C5 were changed in a function-like manner with respect to time so as to match the critical growth rate. That is, the addition was performed at an appropriate addition rate so that small particles were not generated other than the growing seed particles and polydispersion did not occur due to Ostwald ripening. Regarding the addition rate of the solution D5, the rate ratio (molar ratio) with the solution C5 was maintained at 0.06.

Preparation of Em-14 Em-14 was prepared by changing the following points from the preparation of Em-13.

That is, in the preparation of Em-13, the solution A5
The pH of the solution is adjusted to 9.0, and 1/2 amount of the solutions B5 and C5 is added thereto, and then the pH is adjusted to 5.8, and the remaining 1/2 of the solutions B5 and C5 is added.
Amount was added.

Preparation of Em-15 A tabular silver halide emulsion Em-15 having an average silver iodide content of 1.0 mol% was prepared using seed emulsion-1 and the following four kinds of solutions.

A6 ossein gelatin 34.03 g polypropyleneoxy-polyethyleneoxy-disuccinate sodium salt (10% ethanol aqueous solution) 2.25 ml seed emulsion-1 1.218 mol equivalent Water to make 3150 ml B6 potassium bromide 1733 g water to make 3641 ml C6 Silver nitrate 2474 g Finish with water to 4161 ml D6 3% by weight gelatin and silver iodide grains (average grain size 0.05 μ) Fine grain emulsion (*) equivalent to 0.112 mol *: 5.0% by weight containing 0.06 mol potassium iodide To 6.64 liters of the above gelatin aqueous solution, 2 liters each of 7.06 mol of silver nitrate and 7.06 mol of potassium iodide are added.
Added over 10 minutes. The pH during fine particle formation was controlled to 2.0 using nitric acid, and the temperature was controlled to 40 ° C. After particle formation, the pH was adjusted to 6.0 using an aqueous sodium carbonate solution.

Solution A6 was vigorously stirred in the reaction vessel while maintaining the temperature at 60 ° C., and a part of solution B6, a part of solution C6 and a total amount of solution D6 were added thereto by the simultaneous mixing method over 41 minutes, After that, the remaining amounts of the solution B6 and the solution C6 were successively added over 33 minutes by the simultaneous mixing method. During this time, pH was 5.8 and pA
g kept at 9.0 all the time. Here, the addition rates of the solution B6 and the solution C6 were changed in a function-like manner with respect to time so as to match the critical growth rate. That is, the addition was performed at an appropriate addition rate so that small particles were not generated other than the growing seed particles and polydispersion did not occur due to Ostwald ripening. The addition rate of the solution D6 was 0.06 with respect to the rate ratio (molar ratio) with the solution C6.
Kept at.

Further, the above solution D6 was added to 0.30 with respect to the total silver amount.
Halogen substitution was carried out by adding mol% equivalent.

After completion of the addition, insoluble salts were removed in the same manner as Em-1. Subsequently, spectral sensitization and chemical sensitization were performed in exactly the same manner as Em-1.

When the obtained silver halide emulsion was observed with an electron microscope, tabular silver halide grains having an average grain size of 1.04 μ, an average thickness of 0.26 μ, an average aspect ratio of about 4.0 and a grain size distribution of 18.9% were obtained. Met. Also, the average distance between twin planes is
0.020μ, 97% (total number) of all tabular silver halide grains having a twin plane distance to thickness ratio of 5 or more, 49% of 10 or more grains, and 17% of 15 or more grains. Was occupied.

Preparation of Em-16 Em-16 was prepared by changing the following points from the preparation of Em-15.

That is, in the preparation of Em-15, the solution A5
The pH of the solution is adjusted to 9.0, and 1/2 amount of the solutions B5 and C5 is added thereto, and then the pH is adjusted to 5.8, and the remaining 1/2 of the solutions B5 and C5 is added.
Amount was added.

As described above, the average aspect ratio (AR), the average silver iodide content (%) of the obtained emulsions Em-1 to Em-16,
The measurement results of the silver iodide content (%) on the outermost surface are shown below.

The content of silver iodide on the outermost surface was determined as follows.

Emulsion proteolytic enzyme (pronase)
A 0.05 wt% aqueous solution was added, and the mixture was stirred at 45 ° C for 30 minutes to decompose gelatin. This is centrifuged to precipitate the emulsion particles, and the supernatant is removed. Distilled water is then added to disperse the emulsion particles in distilled water and centrifuged to remove the supernatant. Further, the emulsion particles are redispersed in water and thinly coated on a mirror-polished silicon wafer to obtain a measurement sample. Using the sample thus prepared, surface silver iodide measurement by XPS was performed. In order to prevent the sample from being destroyed by X-ray irradiation, the sample is stored in the XPS measurement chamber at -110 to -120 ℃
Cooled to. As a probe X-ray, MgKα was irradiated with an X-ray source voltage of 15 kV and an X-ray source current of 40 mA, and Ag3d5 / 2, Br3d, I3
Measured for d3 / 2 electrons. The integrated intensity of the measured peak was corrected by a sensitivity factor (Sensitivity Factor), and the halide composition of the outermost surface was determined from the intensity ratio of these.

[0190]

[Table 1]

The following additives were added to the obtained emulsion to prepare an emulsion layer coating solution. At the same time, a protective layer coating solution described below was also prepared. Using both coating solutions, the coating amount is 2.
Two slide hopper type coaters were used to simultaneously coat both sides of the support at a speed of 80 m / min so that the amount with gelatin was 0 g / m ² and the amount with gelatin was 3.1 g / m ^2, and it was dried in 2 minutes and 20 seconds. Samples No. 1 to No. 16 were obtained. As the support, a copolymer aqueous dispersion obtained by diluting the copolymer consisting of three types of monomers of glycidyl methacrylate 50 wt%, methyl acrylate 10 wt% and butyl methacrylate 40 wt% to 10 wt% was prepared. Concentration for 175μm X-ray film used as drawing liquid
A polyethylene terephthalate film base colored blue to 0.15 was used.

The additives used in the emulsion are as follows.
The amount of addition is shown in an amount per mole of silver halide.

1,1-Dimethylol-1-bromo-1-nitromethane 70 mg t-Butyl-catechol 400 mg Polyvinylpyrrolidone (molecular weight 10,000) 1.0 g Styrene-maleic anhydride copolymer 2.5 g Nitrophenyl-triphenylphosphonium chloride 50 mg 1 2,3-Dihydroxybenzene-4-sulfonate ammonium 2g

[0194]

Embedded image

C ₄ H ₉ OCH ₂ CH (OH) CH ₂ N (CH ₂ COOH) ₂ 1 g 1-phenyl-5-mercaptotetrazole 15 mg Protective Layer Solution Next, the following was prepared as a protective layer coating solution. The additive is shown in the amount per liter of coating liquid.

Lime-treated inert gelatin 68 g Acid-treated gelatin 2 g Sodium-i-amyl-n-decylsulfosuccinate 1 g Polymethylmethacrylate (matting agent having an area average particle size of 3.5 μm) 1.1 g Silicon dioxide particles (area average particle size 1.2 μm matting agent) 0.5 g (CH ₂ = CHSO ₂ CH ₂ ) ₂ O (hardener) 500 mg C ₄ F ₉ SO ₃ K 2 mg C ₁₂ H ₂₅ CONH (CH ₂ CH ₂ O) ₅ H 2.0 g

[0197]

[Chemical 3]

Photographic properties were evaluated using the obtained samples No. 1 to No. 16. First, use two intensifying screens (KO-250)
Sandwiched between, aluminum tube voltage 80kvp, tube current 1
Exposure was performed by irradiating X-rays at 00 mA for 0.05 seconds. Then, using an automatic processor (SRX-502), processing was performed with a developing solution and a fixing solution having the following formulations.

Developer Formulation Part-A (for 12 liter finish) Potassium hydroxide 450 g Potassium sulfite (50% solution) 2280 g Diethylenetetraamine pentaacetic acid 120 g Sodium bicarbonate 132 g 5-Methylbenzotriazole 1.2 g 1-phenyl-5- Mercaptotetrazole 0.2g Hydroquinone 340g Add water to finish to 5000ml Part-B (for 12l finish) Glacial acetic acid 170g Triethylene glycol 185g 1-Phenyl-3-pyrazolidone 22g 5-Nitroindazole 0.4g Starter (for 12l finish) Glacial acetic acid 120g Potassium bromide 225g Add water to finish to 1.0l Fixer formulation Part-A (for 18l finish) Ammonium thiosulfate (70wt / vol%) 6000g Sodium sulfite 110g Sodium acetate / trihydrate 450g Sodium citrate 50g Gluconic acid 70g 1- (N, N-dimethylamino) -ethyl-5-mercaptotetrazo Preparation of 18 g Part B (for 18l finish) Aluminum sulfate 800g developer is simultaneously added Part A, the Part B into water about 5l, p with glacial acetic finish 12l adding water with stirring dissolved
The H was adjusted to 10.40. This is used as a development replenisher.

20 ml / l of the above-mentioned starter was added to 1 liter of this development replenisher to adjust the pH to 10.26 to prepare a working solution.

The fixing solution was prepared by adding Part A and Part B to approximately 5 liters of water.
Was simultaneously added, water was added while stirring and dissolving to make 18 l, and the pH was adjusted to 4.4 using sulfuric acid and NaOH. This is the fixing replenisher.

The processing temperature is 35 ° C. for development and fixing, respectively.
33 ℃, 20 ℃ water wash, 50 ℃ dry, treatment time is dry to dry 45
Seconds and 25 seconds.

After the processing, the sensitivity was measured and the fixability was evaluated. The sensitivity was represented by the reciprocal of the exposure amount that gives a density of fog +0.5, and was shown as the relative sensitivity when the sensitivity of the sample No. 1 for 45 seconds was 100. The fixing property was evaluated by visually observing the transparency of the unexposed film after processing for 25 seconds, and evaluated according to the following three grades.

◯: No problem Δ: Slightly inferior fixing property (sometimes a problem in practical use) ×: Inferior fixing property (not acceptable for practical use) The obtained results are shown in Table 2 below.

The sample of the present invention further comprises an unexposed sample No.
A load of 5 g was applied to Nos. 1 to 16 with a scratch hardness meter of a needle having a needle head of 0.3 mm, the same developing treatment as described above was performed, and the pressure fog density was measured with a microdensitometer. The degree of fogging is shown as a relative value when the fogging increase of Sample No. 1 is 100. The results obtained are shown in Table 2 below.

The pressure characteristics during development (pressure marks by the rollers of the automatic developing machine, that is, the degree of generation of roller marks) were evaluated as follows. That is, the sample was unexposed and processed in an X-ray automatic developing machine having a special facing roller with strong irregularities for a processing time of 25 seconds. The treatment liquid used was the same as the above treatment liquid. The roller marks generated at that time were observed, and the evaluation results were classified into the following 5 grades according to their degree.

5: No occurrence of roller mark 4: Very slight occurrence 3: Some occurrence (within practical tolerance) 2: Many occurrences (outside practical tolerance) 1: Very many occurrences The obtained results are shown in Table 2. Shown in.

[0208]

[Table 2]

As is clear from Table 2, the sample of the present invention does not impair the sensitivity even in the rapid processing of 25 seconds as compared with the comparative sample. Further, it can be seen that there is no problem in fixing property. Further, it was found that the sample of the present invention had reduced pressure fog and improved pressure characteristics as compared with the comparative sample, and further, there was no generation of roller marks and the pressure fog was good, and there was no problem in practical use. I know there isn't.

[0210]

INDUSTRIAL APPLICABILITY The silver halide emulsion, the silver halide photographic light-sensitive material, the medical silver halide photographic light-sensitive material and the processing method thereof according to the present invention have excellent effects on rapid processing suitability and pressure characteristics.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Shigeaki Takahashi 1 Sakura-cho, Hino-shi, Tokyo Konica Stock Company In-house

Claims (4)

[Claims] 1. 50% or more of the total projected area of silver halide grains contained in the emulsion is tabular silver halide grains having an average aspect ratio of 2 or more and less than 5, and the tabular silver halide grains are The average silver iodide content is 0.8 mol% or less,
A silver halide photographic emulsion characterized in that silver nuclei are formed inside the tabular silver halide grains. 2. A silver halide photographic light-sensitive material containing the silver halide emulsion according to claim 1. 3. A silver halide photographic light-sensitive material for medical use containing the silver halide emulsion according to claim 1. 4. A method for processing a silver halide photographic light-sensitive material for medical use, which comprises processing the silver halide photographic light-sensitive material according to claim 3 for a total processing time of 15 seconds to 90 seconds.