JPH03235937A - Photosensitive silver halide emulsion improved in sensitivity and graininess - Google Patents

Abstract

PURPOSE:To obtain the silver halide photosensitive material having a high sensitivity and excellent graininess by incorporating silver halide particles, the respective particles of which grow while maintaining the sameness in the shapes thereof in all the periods from the start of particle growth to the end of the growth. CONSTITUTION:The silver halide particles, the respective particles of which grow while maintaining the sameness in the shapes thereof in all the periods from the start of the particle growth to the end of the growth, are incorporated into the photosensitive silver halide emulsion contg. the silver halide particles. If notice is given to the surface of certain specific shape among the individual particles of the particles grown by maintaining the sameness in such shapes, the difference is preferably <=20% when the difference between the particle having the highest ratio occupying this surface and the particle having the lowest ratio is taken. The photosensitive material having the high sensitivity and the excellent graininess is obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a silver halide emulsion, and more particularly to a light-sensitive silver halide emulsion with improved sensitivity and graininess.

[Prior art]

It can be said that there is a constant demand for higher sensitivity and higher image quality for photosensitive materials.

For example, it is well known that in recent years, as the sensitivity of color negative films has become higher and the format has become smaller, there has been an increasing demand for higher image quality of silver halide photographic materials.

In response to these demands, core/shell type emulsions having a silver iodobromide phase with a high silver iodide content inside the grains have been extensively researched. In particular, a core/shell type silver iodobromide emulsion having a phase with a high silver iodide content of 15 mol% or more inside the grains prevents recombination of dye holes and electrons and increases the efficiency of latent image formation. , has been attracting attention as a color negative film.

Furthermore, from the viewpoint of sensitivity, contrast, and graininess, silver iodobromide emulsions are known in which the relative standard deviation of the silver iodide content of individual grains is reduced.
The technology is disclosed in No. 332, No. 60-254032, and the like. However, these techniques are applicable only to emulsions in which the silver iodide content of the core is not so high and the average silver iodide content is low, and PAg, crystal habit, etc. during the production of silver halide emulsions. , it could only be applied when crystal growth was performed under special conditions.

In order to coexist with high sensitivity and excellent graininess, it is necessary to have a high silver iodide content phase in the core and further reduce the relative standard deviation of the silver iodide content of individual grains, or to It is necessary to make the internal structure of the grains the same, but the higher the silver iodide content of the silver iodobromide phase in the core, the more uneven the silver iodide content and shape of the grains become. happens. The silver halide emulsion has a small relative standard deviation of the silver iodide content of individual grains and a uniform shape history over a wide range of growth conditions.
It is no exaggeration to say that no technology has been developed to date to produce a core/shell type emulsion having a phase with a high silver iodide content inside the grains.

[Purpose of the invention]

The present invention solves the problems of the prior art described above, achieves both high sensitivity and high image quality, and provides a photosensitive halogen that can constitute a silver halide photosensitive material that is highly sensitive and has excellent graininess. The purpose is to provide a silver oxide emulsion.

[Structure of the Invention] The invention of claim 1 of the present invention provides that in a photosensitive silver halide emulsion containing silver halide grains, each grain is is a photosensitive silver halide emulsion characterized by containing silver halide grains that grow while maintaining the sameness in shape, and with this structure, the above object is achieved.

The invention of claim 2 of the present invention provides that in a photosensitive silver halide emulsion containing silver halide grains, the silver iodide content of each grain is This is a photosensitive silver halide emulsion characterized in that the relative standard deviation of the ratio is 20% or less, and with this structure, the above object is achieved.

The invention of claim 3 of the present invention provides a core consisting essentially of silver iodobromide, and a silver iodobromide coating the core and having a silver iodide content lower than that of the silver iodobromide in the core. , or a photosensitive silver halide emulsion containing silver iodobromide grains consisting of a shell consisting essentially of silver bromide, in which the internal structure of the grains of the emulsion is exactly the same among the individual grains. This is a photosensitive silver halide emulsion characterized by containing the following:

Each invention of the present application will be explained in detail below.

In the invention of claim 1, each particle has a shape in which:
Maintaining identity means that at least the crystal habit and particle size are the same for each particle of interest when the shape of the particles is observed in a scanning electron micrograph at a magnification of at least 10,000 times or more. In particular, in order to observe the fine structure of the surface, it is preferable to use a low acceleration voltage of 2 kV or less.

For example, using normal crystal grains as an example, the individual grains: (1) have the same surface ratios such as (111), (100), (331), etc., and (2) silver halide grains are core/shell grains. In some cases, when the shell is formed, there is no part of the particle where no shell is formed, ■The flatness of the surface is the same, ■There are no twin grains, and the grain size is clearly 0. It does not contain different fine or coarse particles, or aggregated particles made up of two or more particles attached (these can be determined by microscopic observation), etc., when the individual particles are all the same in shape. is an example of maintaining the same shape.

The silver halide grains contained in the emulsion of the first aspect of the invention maintain the same shape at all stages of growth, and therefore can be said to be grains having the same growth history.

The emulsion of the invention of claim 1 contains silver halide grains that grow while maintaining the same formation as described above, and it is preferable that these grains account for most of the grains. It is preferable that 70% or more of the particles in the grain grow while maintaining the same identity in the above shape, more preferably 80% or more, still more preferably 90% or more grow while maintaining the same identity in the above shape. It is preferable that the particles are

In addition, in relation to the above-mentioned item (■), when we focus on the surface of a particular shape among the individual particles of the particles that have grown while maintaining the same shape, we find that the particle in which the ratio of that surface is the largest is It is preferable that the smallest difference in particles is 20% or less. More preferably it is 10% or less, more preferably 5% or less.

Further, in connection with the above-mentioned items 1 to 2, particles with incomplete shell formation, surface flatness, twinned particles, fine particles, coarse particles, aggregated particles, etc. can be easily determined from electron micrographs.

Furthermore, the determination is the same even when there is no crystal habit history of normal crystals between the start of grain growth and the end of grain growth.

In obtaining the emulsion of the invention of claim 1, when the grains constituting the emulsion are particles for forming a new layer with a different halide composition, at the time of forming a new layer with a different halide composition, It may be difficult to maintain the same shape. However, even in such a case, the effects of the present invention can be particularly exhibited by maintaining the same shape. In addition, when the particles are core/shell particles, it is difficult to maintain the identity of the shape of each individual particle, especially during the period from after core formation to the early stage of shell formation, specifically, until 10% of the shell volume is formed. In this case, it is particularly preferable to maintain the same shape.

Next, in the photosensitive silver halide emulsion of the invention according to claim 2 of the present invention, the relative standard deviation of the silver iodide content of each grain is 20 in all periods from the start of grain growth to the end of grain growth. % or less.

Here, the relative standard deviation of the silver iodide content of individual grains is:
It is the value obtained by dividing the standard deviation of the silver iodide content of grains in the emulsion (the method for measuring it will be described later) by the average silver iodide content, and multiplying the result by 100.

Specifically, for example, at least 5
Measure the silver iodide content of 0 emulsion grains, and divide the standard deviation of the silver iodide content by the average silver iodide content.
This is the value obtained by multiplying by 00.

The emulsion of the invention of claim 2 has a relative standard deviation of the silver iodide content of each silver iodobromide grain of 20% or less, but this emulsion has an even higher iodine content between the grains. It is preferable that it be uniform. In other words, when the distribution of iodine content between particles is measured by the EPMA method, the relative standard deviation is 2.
It is required that the content be 0% or less, but it is preferably 15% or less, particularly 10% or less.

Next, the invention of claim 3 of the present application provides a core consisting essentially of silver iodobromide, and an iodobromide core that covers the core and has a silver iodide content lower than that of silver iodobromide in the core. In a light-sensitive silver halide emulsion containing silver iodobromide grains consisting of a shell consisting essentially of silver oxide or silver bromide, the internal structure of each grain of the emulsion is exactly the same among the individual grains. It is characterized by containing particles.

In the invention of claim 3, it is preferable that the core consisting essentially of silver iodobromide consists essentially of silver iodobromide containing 20 mol % or more of silver iodide.

Further, the average silver iodide content of the emulsion according to the invention of claim 3 is 6
It is preferable that it is mol% or more. Furthermore, it is preferred that the relative standard deviation of the silver iodide content of individual grains of the emulsion is 20% or less.

In the photosensitive silver halide emulsion of the invention of claim 3, the cores of the silver iodobromide grains preferably contain silver iodide in an amount of 20 mol% or more, more preferably 25 mol% or more of silver iodide. and the shell covering the core must consist essentially of silver iodobromide or silver bromide having a lower silver iodide content than the silver iodobromide of the core.

The preferred silver iodide content of the shell is 6 mol% or less, more preferably 3 mol% or less.

The average silver iodide content of the silver iodobromide grains contained in the emulsion of the present invention is preferably 6 mol % or more, more preferably 7 mol % or more.

In this specification, the term "substantially consists of" means that it may contain other components to the extent that the effects of the present invention are not impaired; for example, silver halide in the emulsion of the invention of claim 3 The particles can also contain silver chloride within a range that does not impair the effects of the present invention.

The content difference between the core portion with a high silver iodide content and the shell portion with a low silver iodide content of the silver halide grains may have a sharp boundary or may vary continuously.

Moreover, those having an intermediate layer between the core and the shell having a silver iodide content between those of the core and the shell are particularly preferably used.

In the case of a core/shell type silver halide grain having the intermediate layer, the difference in silver iodide content between the shell and the intermediate layer and between the intermediate layer and the core is preferably 3 mol% or more, and the iodide content between the shell and the core is preferably 3 mol% or more. It is preferable that the difference in silver content is 6 mol% or more.

The silver iodide content of individual silver halide grains and the average silver iodide content in the emulsions of each invention of this application are determined by the EPMA method (Electronl'robe Micro Analyzer).
lyzer method).

This method is a technique in which a well-dispersed sample is prepared so that the emulsion grains do not come into contact with each other, and elemental analysis of extremely small portions is performed by X-ray analysis using electron beam excitation by irradiating the sample with an electron beam.

By this method, the halogen composition of each grain can be determined by determining the characteristic X-ray intensities of silver and iodine emitted from each grain.

If the silver iodide content of at least 50 grains is determined by the EPMA method, the average silver iodide content can be determined from the average thereof.

1 2 The equipment used for measurement does not require any special specifications, but
In the examples of the present invention described later, the silver iodide content of the emulsion was measured using an X-ray microanalyzer JXA-8621 manufactured by JEOL Ltd. The measurements were performed while cooling to a low temperature to eliminate electron beam damage.

Further, the silver iodide content of the shell (and surface layer, if necessary) of the silver halide emulsion can be measured by X-ray photoelectron spectroscopy.

The photosensitive silver halide emulsion of the invention of claim 3 of the present application is:
In the invention according to claim 3, the silver halide grains are characterized in that the internal structure of the grains is exactly the same among the individual grains, wherein the grains whose internal structure is the same among the individual grains are large in size in the emulsion. Specifically, it is preferable that 70% or more of the grains in the emulsion have exactly the same internal structure, more preferably 80% or more, and still more preferably It is 90% or more.

The internal structure of a grain can be easily confirmed by direct electron microscopy using an ultrathin section of a silver halide grain (see, for example, the analysis method described in JP-A-63-331327).

That is, it can be confirmed by using sample preparation, measurement methods, and analysis methods as described below.

1. Silver halide grains are separated and dried by removing gelatin in the emulsion or sample film by decomposition, washing, centrifugation, etc.

2. Place the dried silver halide particles into a gelatin capsule. (a) 3. Inject epoxy resin to about 1/4 to 1/3 of the capsule and mix and disperse well with silver halide particles. (b) 4. Epoxy resin is further injected into the capsule, left to stand, and then heated to polymerize and harden. (c, >5, Trim the hardened block to a 0.3-own angle and use a diamond knife to create an ultra-thin section with a thickness of about 40 nm. (d) 6. Take the ultra-thin section into an electron microscope mesh, 3. After drying, a thin layer of carbon is vacuum-deposited. (e) 7. The mesh is fixed in a cooling holder and observed with an electron microscope under cooling with liquid nitrogen.

According to the above method, ultrathin sections with a thickness of about 40 nm are created, so for example, particles of 1 μm are divided into 25 ultrathin sections. As a result, it is possible to observe the internal structure of polyhedral particles, and layered boundary patterns corresponding to double and multilayer structures can be confirmed.

In the Examples described later, an H-600 type apparatus (Hitachi, Ltd.) was used for analyzing the silver halide grains of the present invention.

The photosensitive silver halide emulsions of each invention of the present application are preferably highly monodisperse. That is, the width of the distribution defined by is preferably 20% or less, more preferably 15% or less.

According to the findings of the present inventors, the photosensitive emulsions of the inventions of the present application that exhibit the effects of the present invention are produced by a method for producing silver halide grains in which a silver salt aqueous solution and a halide aqueous solution are supplied by a double jet. When obtained, it requires a fairly complicated procedure and is difficult to manufacture. On the other hand, the emulsion of the present invention can be effectively prepared by the following method. That is, during at least one period of the growth process of the silver halide grains contained in the emulsion, the silver halide grains which are silver iodobromide grains contained in the emulsion (hereinafter referred to as rAgX grains (1) for convenience of explanation) Silver halide fine particles with a solubility product equal to or lower than (
It can be effectively prepared by a method in which silver halide grains are grown in the presence of the same <rAgX grains (2).

The solubility product being equal or lower means that the solubility product of the AgX particles (2) is the same as or smaller than the solubility product of the AgX particles (1). In addition, the solubility product in this specification is
In the ordinary chemical sense.

The AgX grains (1) may themselves contain a mixture of 25 6 or more types of silver halide compositions. Alternatively, grains having different silver halide compositions may be mixed to form an emulsion having mixed silver halide compositions. When silver halide compositions are mixed inside the grains, the two or more types of silver halides mixed may be uniformly distributed in the grains or may be non-uniformly distributed. .

Furthermore, the particle size of the AgX particles (1) is preferably 3.0 μm or less in equivalent sphere diameter.

The particle shape of the AgX particles (1) is not particularly limited, and may be any shape such as cubes, octahedrons, tetradecahedrons, tabular grains, and potato-shaped particles.
A normal crystal is preferred, and an octahedron is particularly preferred.

The emulsion of the present invention containing the AgX grains (1) may be used in at least one silver halide emulsion layer in a light-sensitive material in order to bring about the effects of the present invention. In the case of two or more, it is preferable to use them in all emulsion layers.

It is preferable that AgX grains (1) account for at least 30 mol % of all the silver halide grains contained in the emulsion layer, particularly preferably 60 mol % or more.

The emulsion of the present invention has a solubility product equivalent to that of AgX grains (1),
Or, AgX particles (2) with a smaller solubility product are present during at least one period of the growth process of AgX particles (1), and the growth of AgX particles (1) is performed in the presence of the AgX particles (2). It can be formed by Here, the AgX particles (2) are used to grow the AgX particles (1) by being present until the supply of grain growth elements (halogen ion liquid, silver ion liquid, etc.) for the AgX particles (1) is finished. be able to.

The AgX particles (2) are fine particles, and the term fine particles here means that the solubility product is equal to or smaller than that of the AgX particles (1).

Generally, the average particle size of the AgX particles (2) is smaller than the average particle size of the AgX particles (1), but in some cases it may be larger. Moreover, the AgX particles (2) generally have substantially no photosensitivity 7 8 . The average particle diameter of this AgX particle (2) is 0.00
It is preferably 1 to 0.7 μm, and preferably 0.01 to 0.7 μm.
The thickness is more preferably 3 μm, particularly preferably 0.1 to 0.01 μm.

Hereinafter, when forming the photosensitive emulsion of the present invention, AgX particles (
The case where the method using 2) is adopted will be described. Ag
The manner in which the X particles (2) are made to exist will be described in detail as follows, together with a description of the grain growth process of AgX (1).

The first method for growing AgX (1) is to use silver halide seed grains and grow the seed grains using a water-soluble silver salt solution and a water-soluble halogen solution as grain growth elements.
This is a method for obtaining gX particles (1). In the second method, silver halide nuclei are formed using the above two solutions (herein referred to as grain growth elements) without using seed grains, and then the grains are grown to form AgX grains ( This is the method to obtain 1). The first method is advantageous in terms of reproducibility of the particle size of AgX particles (1).

The AgX particles (2) grow at least once during the growth process of the AgX particles (1), that is, at the latest when the AgX particles (1) grow.
) until the growth of AgX particles (1) is completed, it is necessary to make them exist in a suspension system (hereinafter referred to as mother liquor) which serves as a place for preparing AgX particles (1).

When using silver halide seed grains, AgX grains (2
) may be present in the mother liquor before the seed particles,
It may be added to the mother liquor containing seed particles prior to the addition of the particle growth element, it may be added during the addition of the particle growth element, or it may be added at two or more of the above-mentioned addition periods. It may also be added.

When grain growth is performed after silver halide nucleation without using seed grains, it is preferable to add AgX grains (2) after nucleation, even before addition of grain growth elements.
It may be added during the addition, or may be divided into two or more periods.

Furthermore, the AgX particles (2) and the particle growth element may be added all at once, continuously, or intermittently.

The AgX particles (2) and particle growth elements can be added to the mother liquor by a multi-jet method such as a double-jet method under controlled conditions such as pi (, PAg, temperature, etc.) at a rate compatible with the particle acid length. preferable.

In particular, it is preferable that p and Ag have regions that are not constant during grain growth.

The AgX grains (2) and silver halide seed particles may be prepared in the mother liquor, or may be prepared outside the mother liquor and then added to the mother liquor.

As the water-soluble silver salt solution used for preparing the AgX particles (2), an ammoniacal silver salt solution is preferable.

When the AgX grain (1) is silver iodobromide, the halogen composition of the AgX grain (2) is silver iodide, or more than the silver iodobromide grain that is the growing AgX grain (1). Silver iodobromide having a high iodine content is also preferred. In particular, silver iodide is particularly preferred.

The AgX (1) grains produced by growth are silver iodobromide, and in this case, it is preferable that all the iodine used for grain growth be supplied as AgX grains (2), but within a range that does not impair the effects of the present invention. A portion may be supplied as a halogen aqueous solution.

It is preferable that the AgX particles (2) have good monodispersity.

The composition of the silver halide seed grains is silver chloride, silver bromide,
Various materials such as silver chlorobromide, silver chloroiodide, silver iodobromide, and silver chloroiodobromide can be used as desired.

In the step of preparing the AgX particles (1), the temperature of the mother liquor is preferably 10 to 70°C, more preferably 20 to 6°C.
0°C, pAg is preferably 6 to 11, more preferably 7.5 to 10.5, and pH is preferably 5 to 11, more preferably 6 to 10.

The emulsions of the inventions of this application, or other emulsions used in combination as necessary when constituting a light-sensitive material, are adsorbed onto silver halide grains during their preparation (including the preparation of the seed emulsion). Substances other than gelatin having properties may be added. Such adsorbed substances include, for example, compounds used in the art as sensitizing dyes, antifoggants or stabilizers;
or heavy metal ions are useful. Specific examples of the above-mentioned adsorptive substances are described in Tokoku Kokai No. 62-7040.

Among the adsorbent substances, it is preferable to add at least one of an antifoggant and a stabilizer during preparation of the seed emulsion in order to reduce fog and improve stability over time of the emulsion.

Among the antifoggants and stabilizers, heterocyclic mercapto compounds and/or azaindene compounds are particularly preferred.

Specific examples of more preferred heterocyclic mercapto compounds and azaindene compounds are described in detail in JP-A-63-41848, which can be used.

The amount of the heterocyclic mercapto compound and azaindene compound added is not limited, but is preferably 1X10-' to 3X10-'' and more preferably 5X10-' to 3X10-'' mole per mole of silver halide. This amount is appropriately selected depending on the manufacturing conditions of the silver halide grains, the average grain size of the silver halide grains, and the type of the above-mentioned compound.

For a finished emulsion that has been provided with predetermined grain conditions, desalting can be carried out by a known method after silver halide grain formation. As a desalination method, JP-A-63-24
3936, JP-A-1-185549, an agglomerated gelatin agent used for desalting particles as seed particles, etc. may be used, or the Tardel water washing method, which is performed by gelatinizing gelatin, may be used. Inorganic salts consisting of polyvalent anions, such as sodium sulfate, anionic surfactants,
Anionic polymers (e.g. polystyrene sulfonic acid)
A coagulation method using .

Generally, the silver halide grains desalted as described above are redispersed in gelatin to prepare an emulsion.

The emulsions of each invention of the present application, or other emulsions used in combination as necessary, can be chemically sensitized by conventional methods. In other words, sulfur sensitization using compounds containing sulfur that can react with silver ions or active gelatin, selenium sensitization using selenium compounds, reduction sensitization using reducing substances, and noble metal sensitization using gold or other noble metal compounds. Sensitive methods and the like can be used alone or in combination.

3 4 As a chemical sensitizer, for example, a chalcogen sensitizer can be used, and among them, a sulfur sensitizer and a selenium sensitizer are preferable.

Examples of the sulfur sensitizer include thiosulfate, allylthiocarbazide, thiourea, allylisothiocyanate, cystine, p-toluenethiosulfonate, and rhodanine. Others: U.S. Patent No. 1,574,944, U.S. Patent No. 2,410,689, U.S. Patent No. 2.278.947, U.S. Pat.
, No. 728,668, No. 3,501,313, No. 3,
No. 656゜955, West German Publication (OLS) 1,
No. 422.869, JP-A-56-24937, JP-A No. 55
Sulfur sensitizers described in No.-45016 and the like can also be used.

The amount of sulfur sensitizer added varies over a considerable range depending on various conditions such as pH 1 temperature and size of silver halide grains, but as a guide, 10 -
The amount is preferably about 7 mol to 10 −1 mol.

Examples of selenium sensitizers include aliphatic isoselenocyanates such as allyl isoselenocyanate, selenoureas, selenoketones, selenoamides, selenocarboxylic acid salts and esters, selenophosphates, diethylselenide, diethylselenide, etc. Selenides can be used, specific examples of which can be found in U.S. Pat. No. 1.574.
No. 944, No. 1602, No. 592, L623,499
listed in the number.

Furthermore, reduction sensitization can also be used together. Examples of the reducing agent include stannous chloride, thiourea dioxide, hydrazine, and voriazine.

Further, noble metal compounds other than the total, such as palladium compounds, etc. can also be used in combination.

The silver iodobromide grains (AgX grains (1)) in the emulsions of each invention of the present application preferably contain a gold compound. As the gold compound preferably used in the present invention, the oxidation number of gold may be +1 or +3, and various types of gold compounds are used. Typical examples include chlorauric acid salts, potassium chloroaurate, auric trichloride, potassium auric thiocyanate, and potassium iodoaurate.

Examples include tetracyanoohlic azide, ammonium aurothiocyanate, pyridyl trichlorogol, gold sulfide, and gold selenide.

The gold compound may be used to sensitize the particles, or may be used so as not to substantially contribute to sensitization.

The amount of the gold compound added varies depending on various conditions, but as a guideline it is from 10<-8> to 10<-1> mol, preferably from 10<-7> to 10<-2> mol per mole of silver halide. These compounds may be added at any time during silver halide grain formation, during physical ripening, during chemical ripening, or after completion of chemical ripening.

The emulsion can be spectrally sensitized to a desired wavelength range using a sensitizing dye. The sensitizing dyes may be used alone or in combination of two or more.

Along with the sensitizing dye, the emulsion contains a dye that itself does not have a spectral sensitizing effect, or a supersensitizer, which is a compound that does not substantially absorb visible light and enhances the sensitizing effect of the sensitizing dye. Good too.

When a silver halide photographic light-sensitive material is constructed using the emulsion of each invention of this application, it can be used as any light-sensitive material, and black-and-white silver halide photographic light-sensitive materials (e.g., It can be used for color photographic materials (for example, color negative films, color reversal films, color vapors, etc.).

Additionally, photosensitive materials for diffusion transfer (e.g. color diffusion transfer elements,
silver salt diffusion transfer element), heat-developable photosensitive material (black and white, color)
It can also be used for

In the case of multicolor photographic materials, blue-sensitive, green-sensitive and red-sensitive halogen compounds containing yellow, magenta and cyan couplers are usually used as photographic couplers to perform subtractive color reproduction. It has a structure in which a silver emulsion layer and, if necessary, a non-photosensitive layer are laminated on a support in an appropriate number and order of layers, but the number and order of layers depend on the important performance,
It may be changed as appropriate depending on the purpose of use.

Additives such as antifoggants, hardeners, plasticizers, latex, surfactants, color antifoggants, matting agents, lubricants, and antistatic agents can be optionally used in the photographic light-sensitive materials.

7 8 Furthermore, images can be formed on photographic materials by performing various black-and-white development treatments or color development treatments.

As the color developing agent used in the color development process, aminophenol derivatives and p-phenylenediamine derivatives which are widely used in various color photographic processes can be used.

In addition to the primary aromatic amine color developing agent, known developer component compounds can be added to the color developing solution applied to the processing of the photographic light-sensitive material. It is also possible to treat systems that do not contain benzyl alcohol, which poses a problem in terms of pollution load.

The pH value of the color developer is usually above 7, most commonly about 10-13.

The color development temperature is usually 15°C or higher, and -2 for boat fishing.
The temperature range is from 0″C to 50°C. For quick development, 3
Preferably, the temperature is 0°C or higher. In addition, conventional processing takes 3 to 4 minutes, but if an emulsion is created for rapid processing, the color development time is generally 20 to 60 seconds, or even 3 minutes.
A range of 0 seconds to 50 seconds is also possible.

When a photographic light-sensitive material is subjected to color development processing, bleaching processing and fixing processing are generally performed after color development.

Bleaching treatment may be performed simultaneously with fixing treatment.

After the fixing process, a washing process is usually performed.

In addition, as an alternative to the water washing treatment, a stabilization treatment was performed.90 [Example] Next, the invention of the present application will be specifically explained with reference to Examples, but each invention is not limited by these.

Example-1 First, emulsions Em-A to Em-G used in this example will be described below.
The method of preparation is shown.

Em-A's. ′ The following aqueous solutions (a-1) to (a-6) were used.

Aqueous solution (a-1) Add L water to make 2148ml Aqueous solution (a-3) Aqueous solution (a 4) Aqueous solution (a 5) Aqueous solution (a-2) 1 2 Add clean water to make 3j2.

Aqueous solution (a-6) It was added by the pull jet method.

Then, the pH of the solution obtained above was adjusted to 6.0. pAg 10
．． 1, the emulsion was desalted and washed with water by a conventional method to obtain a monodisperse emulsion Em-A having an average grain size of 0.8 μm and an average silver iodide content of 8.0 mol %.

However, the pH and pAg conditions during growth are as shown in Table 1 with respect to the proportion of silver used during growth.

A monodisperse silver iodobromide emulsion 0.407 containing 2 mol% silver iodide and having an average grain size of 0.27 μm was added to the aqueous solution (a-1) having the above composition which was vigorously stirred at a temperature of 50°C. Molar equivalents were added as seed particles to adjust pH and PAg to acetic acid and KB.
It was prepared using r aqueous solution.

Afterwards, while controlling pH and PAg,
First, add the above aqueous solutions (a-2) and (a-3), then add the aqueous solutions (a-4) and (a-5), then add the aqueous solutions (a-2) and (a-3), and finally Aqueous solution (a-2) and (a-
6), respectively, in Table 1. However, in Table 1, Ag (%) is the ratio of the amount of silver used up to the middle of growth to the amount of silver required to grow the seed particles. Also, → means to keep the pH and pAg constant, and \ means to continuously lower it (the same applies in the following description).

Em-B-91 In the preparation solution of the above emulsion Em-A, aqueous solution (a-3)
Change the aqueous solution (b-3) to the aqueous solution (b-3) below. Change the aqueous solution (a-6) to the aqueous solution (b-6),
b-6) Replace aqueous solution (a-5) with the following aqueous solution (b-5), and prepare emulsion E by following the preparation method for emulsion Em-A in all other cases.
m-B was obtained. Em-B is a monodispersed emulsion with an average grain size of 0.8 μm and an average silver iodide content of 6.86 mol %.

1 complete ↓” Made by Ezushi 1 Next, a method for preparing emulsion Em-C will be described.

The following aqueous solutions (c-1) to (c-4) were used.

5 G Aqueous solution (c-1) Aqueous solution (c-2) Aqueous solution (c-3) Emulsion solution containing Agl fine particles (average particle size 0.06 μm) (c-4) Agl fine particle stock solution (45.6 g gelatin 1 mol) Contains AgI] (1467m
F1 mole A g I) 1239mf4
-Hydroxy-6-methyl 1.3,3a,7-chitrazaindene 5.22g Add water to make 2294mN.

A monodisperse silver iodobromide emulsion 0.407 with an average grain size of 0.27 μm containing 2 mol % of silver iodide was added to an aqueous solution (c-1) having the above composition which was vigorously stirred at a temperature of 60°C. Molar equivalents were added as seed particles, and the pH and pHg of acetic acid and KB
It was prepared using r aqueous solution.

After that, each aqueous solution (c-2), (c-3), and (c-4) was simultaneously added at the flow rates shown in Tables 3 and 4 while controlling pt+ and pHg as shown in Table 2. Added by mixing method.

Next, a phenylcarbamyl gelatin solution was added to the solution obtained above, and the pH of the solution was adjusted to cause the particles to settle and coagulate, followed by desalting and washing with water.

Thus, with an average grain size of 0.8 μm and an average silver iodide content of 8.
．． A monodispersed emulsion Em-C of 0 mol % was obtained.

The results of measurements by powder X-ray diffraction revealed that Em-C was an emulsion having a core with an Agl content of 35 mol%.

8 Table-3 (C2) (C3) Addition flow rate of each aqueous solution According to the preparation method, (c-2), (
c-3), (c-4) By changing the addition flow rate balance of each aqueous solution, the silver iodide content of the phase with the highest silver iodide content inside the grains can be changed from 35 mol % of emulsion Em-C to 20 mol %. %
Emulsion Emulsion was obtained. Emulsion Em-D is
It is a monodisperse emulsion with an average grain size of 0.8 μm and an average silver iodide content of 8.0 mol %.

11J Em-E A monodisperse emulsion with an average grain size of 0.8 μm was prepared. This is designated as emulsion Em-E.

Also, according to the preparation method of emulsion Em-C, the average silver iodide content was 6.86 mol%, and the average grain size was 0.8 μm with a high silver iodide core with a silver iodide content of 20.0 mol%. A monodispersed emulsion was prepared. This is designated as emulsion Em-F.

2 In addition, according to the preparation method of emulsion Em-C, the average silver iodide content was 10.0 mol%, and the average grain size was 0.2 mol% with a high silver iodide content core having a silver iodide content of 20.0 mol%. A monodisperse emulsion of 8 μm was prepared. This is designated as emulsion Em-G.

The shapes of individual grains and the relative standard deviation of silver iodide content in these E m-A-E m-G were measured by sampling 10 point emulsions at appropriate time intervals from the start of grain growth to the end of growth. did. Further, the emulsion Em-A-Em-G obtained as described above was analyzed by the method described in Japanese Patent Application No. 63-331327 (analysis method using electron microscopy described above) to determine the shape of the internal phase of the grains. observed. These results are shown in Table-5.

As can be seen from the results in Margin Table 5 below, among the emulsions using Agl fine grains for grain growth, especially Em-C to Em-E, many grains have the same shape at each point of grain growth. In particular, since 70% or more of the particles have the same shape, Claim 1 of the present application
1 shows a preferred embodiment of the invention. Also, emulsion C
, D also have a small relative standard deviation of Agl content at each point of grain growth of 20% or less, and correspond to the photosensitive emulsion of the invention of claim 2 of the present application.

That is, in particular, Em-C and Em-D were preferable, with 70% or more of particles having the same shape and a relative standard deviation of Agl content of 20% or less in all samples taken during particle growth.

In addition, Em-C and Em-D have 80% or more of the particles having the same internal structure, indicating a particularly preferred embodiment of the invention of claim 3 of the present application.

Next, each of the emulsions E m -A -E m -G was subjected to gold-sulfur sensitization, and spectral sensitization was performed using the sensitizing dyes S-1 and S-2 shown below in combination. after,
Magenta coupler M-1 was added and coated on a triacetyl cellulose film support (56t) The above samples Nos. 1 to 4 were exposed to wedge light through a yellow filter, and then subjected to the following development treatment.

Processing process (38℃) Color development Standard 2 minutes 45 seconds bleaching 6 minutes 30 seconds washing with water
Fixed for 3 minutes and 15 seconds
Washing with water for 6 minutes and 30 seconds Stabilization for 3 minutes and 15 seconds Drying for 1 minute and 30 seconds The composition of the treatment liquid used in each treatment step is as follows.

Color developer> 4-Amino-3-methyl-N-ethyl-N(β-hydroxyethyl)aniline sulfate 4.75 g 4.25 g 2.0 g 37.5 g Anhydrous sodium sulfite hydroxyamine 1/ Disulfate Anhydrous potassium carbonate 7 Sodium bromide 1.3 g Nitrilotriacetic acid trisodium salt (monohydrate) 2.5 g Potassium hydroxide 1.0 g Add water to make 1r.

<Bleach solution> Ethylenediaminetetraacetic acid iron ammonium salt 100.0
g Ethylenediaminetetraacetic acid diammonium salt 10.0 g
Ammonium bromide 150.0g
Glacial acetic acid 10 mZ
Add water to adjust to 11, and use ammonium water to adjust the pH to
Adjust to 6.0.

Fixer> Ammonium thiosulfate 175.0
gAnhydrous sodium sulfite 8.5g
Add 2.3g of sodium metasulfite water and 1! and adjust the pH to 6.0 using acetic acid.

<Stabilizer> Formalin (37% aqueous solution) 1.5m/
Konidax (manufactured by Konica Corporation) 7.5m7
Add water to make 11.

Relative sensitivity was measured for each sample obtained using green light. The results are shown in Table 6.

9 0 Table-6 As shown in Table-6, the samples according to the inventions of each claim of the present application have shown favorable results, and are particularly preferred embodiments of the invention of claims 1 and 3, and Sample No. 3 using the emulsion according to the invention. No. 4 has extremely good sensitivity and RMS granularity.

〔Effect of the invention〕

As described above, according to the light-sensitive silver halide emulsions of the inventions of the present application, a light-sensitive material with high sensitivity and excellent graininess can be constructed.

Claims (1)

[Claims] 1. In a photosensitive silver halide emulsion containing silver halide grains, each grain maintains the same shape in the entire period from the start of grain growth to the end of growth. A photosensitive silver halide emulsion characterized in that it contains silver halide grains that grow. 2. In a photosensitive silver halide emulsion containing silver halide grains, the relative standard deviation of the silver iodide content of each grain is 20% during the entire period from the start of grain growth to the end of growth. A photosensitive silver halide emulsion characterized by the following: 3. A core consisting essentially of silver iodobromide, and a core consisting essentially of silver iodobromide or silver bromide covering the core and having a lower silver iodide content than the silver iodobromide of the core. A photosensitive silver halide emulsion containing silver iodobromide grains consisting of a shell consisting of a shell, which is characterized in that the emulsion contains grains whose internal structure is exactly the same among individual grains. sexual silver halide emulsion.