JPH0216537A - Direct positive silver halide photographic sensitive material - Google Patents

Abstract

PURPOSE:To obtain a direct positive image having the high max. image density and the low min. image density by providing silver halide emulsion layers contg. internal latent image type silver halide particles and non-photosensitive layers contg. non-image forming silver halide particles to the above material and processing the material in the presence of a fogging agent. CONSTITUTION:This photosensitive material has at least one layer of the silver halide emulsion layers contg. the internal latent image type silver halide particles which are not previously fogged and the non-photosensitive layers contg. the non-image forming silver halide particles. The material is processed in the presence of the fogging agent. The silver halide emulsion to be used is the emulsion having the silver halide particles which are not subjected to the fogging on the particle surfaces, form the latent image mainly within the silver halide particles and have the greater part of photosensitive nuclei in the particles. Arbitrary silver halide, for example, silver bromide, silver chloride, silver chlorobromide, silver iodobromide, silver chloroiodobromide, etc., are included in the emulsion. The non-image forming silver halide particles are preferably fine particles. The direct positive image having the sufficiently high max. image density and the sufficiently low min. image density is rapidly and stably obtd. in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a direct positive silver halide photographic material, and more particularly to an internal latent image type direct positive silver halide photographic material processed in the presence of a fogging agent. Regarding materials.

[Background of the invention]

Conventionally known methods for obtaining direct positive images are mainly divided into two types. One type is to obtain a positive image after development by using a silver halide emulsion that has fog nuclei in advance and destroying the fog nuclei or latent image in exposed areas using solarization or the Burschel effect. It is. Another type uses an internal latent image type silver halide emulsion that does not produce fog (generally surface fog) until image exposure, and then performs fogging treatment (nucleation treatment) after image exposure, and then surface development. A positive image can be obtained by performing surface development while carrying out fogging treatment after image exposure.

Of the above two methods for forming a positive image, the latter type of method has -
It has high numerical sensitivity and is suitable for applications that require high sensitivity.

Various techniques are known in this technical field. For example, U.S. Patent Nos. 2,592.250, 2.466.957, 2,497.875, and 2
, No. 588,982, No. 3,761.266, No. 3,
The methods described in No. 761.276, No. 3,796.577 and British Patent No. 1,151.363 are known.

Regarding the formation mechanism of positive images, for example, Photographic Science and Engineering (Ph.D.
otographic 5science and en
gineering), Vol. 20, p. 158 (1976), it is considered as follows. Photoelectrons generated within the silver halide crystal grains by imagewise exposure are selectively captured inside the grains, forming an internal latent image.

This internal latent image acts as an effective capture center for electrons in the conductive band, so in exposed particles, electrons injected during the subsequent fogging and development process are captured internally and strengthen the latent image. become. In this case, the latent image is all internal and is not developed. On the other hand, for particles that have not undergone image exposure, at least some of the injected electrons are captured on the particle surface, and the particles are developed by surface development.

The fogging treatment may be performed by exposing the entire surface to light, chemically using a fogging agent, using a strong developer, or heat treatment. The internal latent image type silver halide hole photographic emulsion is a silver halide photographic emulsion that has photosensitive nuclei mainly inside the silver halide crystal grains, and a latent image is formed inside the grains upon exposure. say.

Among the fogging treatments mentioned above, in the conventional chemical fogging method, pH
Since a compound that can only obtain a fogging effect at a high pH of 12 or more is used, the developing agent is likely to deteriorate due to air oxidation, resulting in a disadvantage that the developing activity is significantly reduced. Also, because the development speed is slow, processing time becomes longer.
This tendency is particularly strong for low pn developer diameters. pH is 12
Even with the above, the drawback that the development time becomes long cannot be avoided.

On the other hand, the photofogging method does not require a high pu, which is advantageous in practice. However, there are various technical problems in serving a wide range of purposes. That is, since the photofogging method is based on the formation of fogging nuclei by photodecomposition of silver halide, the appropriate exposure illuminance and exposure amount vary depending on the type and characteristics of the silver halide used. Therefore, it is difficult to obtain a certain level of performance, and the developing device is complicated and expensive. Furthermore, there is a drawback that the development time is long.

As described above, with the conventional fogging method, it is difficult to quickly obtain stable and good direct positive images. As a means to solve this problem, compounds that exhibit a fogging effect even at pH 12 or lower have been proposed in JP-A-52-69613, U.S. Patent Nos. 3,615,615 and 3,850,638. Fogging agents have the disadvantage that they act on silver halide during storage of the photosensitive material before processing, or the fogging agent itself decomposes, reducing the maximum image density after processing.

US Pat. No. 3,227,552 describes the use of hydroquinone derivatives to increase the development rate of medium densities. However, even when this is used, the development speed is not sufficient, and in particular, with a developer having a pH of 12 or less, a completely insufficient development speed can be obtained.

JP-A-60-170843 describes that the maximum image density can be increased by adding a mercapto compound having a carboxyl group, but this effect is small.

JP-A-55-134848 discloses a treatment solution containing a tetrazaindene compound (pH 12) in the presence of a fogging agent.
, 0) to reduce the minimum image density and prevent the formation of a re-inverted negative image.

However, with this method, the maximum image density cannot be increased and the development speed cannot be increased.

Furthermore, Japanese Patent Publication No. 12709/1983 describes the addition of triazolinthione and tetrasilydithione compounds as antifogging agents to photosensitive materials on which positive images are directly formed by the photofogging method. . However, even with this method, high maximum image density and fast development speed could not be achieved.

As described above, there has been no technique to obtain a direct positive image having a satisfactory high maximum image density and low minimum image density in a short period of time. In addition, there is a problem in that, in general, direct positive emulsion diameters have high sensitivity, and re-inversion negative images often occur during high-intensity exposure.

[Purpose of the invention]

Accordingly, an object of the present invention is to provide a direct-positive silver halide photographic light-sensitive material from which a direct-positive image having a sufficiently high maximum image density and a sufficiently low minimum density can be obtained quickly and stably.

[Structure of the invention]

The above object of the present invention is to have at least one silver halide emulsion layer containing internal latent image type silver halide grains which have not been pre-fogged and a non-photosensitive layer containing non-image forming silver halide grains. This is achieved by a direct positive silver halide photographic material, which is characterized in that it is processed in the presence of a fogging agent.

The present invention will be explained in more detail below.

The silver halide emulsion used in the light-sensitive material of the present invention is a halogen emulsion that forms a latent image mainly inside the silver halide grains without fogging the grain surfaces in advance, and has most of the photosensitive nuclei inside the grains. It is an emulsion having silver halides, and includes any silver halide such as silver bromide, silver chloride, silver chlorobromide, silver iodobromide, silver chloroiodobromide, and the like.

The meaning that the grain surfaces are not prefogged means that the emulsion used in the present invention is coated on a transparent film support with a thickness of 35 m
gAg/cm" is developed with the following surface developer A at 20°C for 10 minutes without exposure, and the density obtained does not exceed 0.6, preferably 0.4. .

Surface developer A Metol 2.5 g L-ascorbic acid 10 g Sodium metaborate (tetrahydrate) 35 g Potassium bromide 1 g Add water and prepare 1 (2) The silver halide emulsion according to the present invention is prepared as described above. After exposing the test piece, a sufficient density is obtained when the test piece is developed with internal developer B having the following formulation.

Internal developer B Metol 2.0g Sodium sulfite (anhydrous) 90.0g Hydroquinone 8.0g Sodium carbonate (l hydrate) 52.5g Potassium bromide 5.0g Potassium iodide
Add 0.5g water
More specifically, a portion of the specimen was exposed to a light intensity scale for a defined period of time up to about 1 second, and then treated with internal developer B at 20°C for 1 hour.
a maximum of at least 5 times, preferably at least 10 times, that obtained when another part of the specimen exposed under the same conditions is developed in surface developer A for 10 minutes at 20° C. when developed for 0 minutes. It indicates the concentration.

Specific examples of internal latent image type silver halide grains include conversion type silver halide grains described in U.S. Pat. No. 2,592.250 and US Pat. No. 3,206.313.
No. 3,317,322, No. 3,761.266, No. 3,761.267, No. 4,395.478,
Core/shell type silver halide grains containing an internal chemical sensitizing liquid or multivalent gold layer ions described in U.S. Pat. No. 4,504.570, U.S. Pat.
Examples include laminated silver halide grains described in No. 957.488.

Silver halide grains are prepared by an acid method, a neutral method, an ammonia method, or the like. The particles may be grown all at once, or may be grown after seed particles are produced. The method of making and growing the seed particles may be the same or different. The silver halide emulsion containing the silver halide grains may be prepared by mixing halide ions and silver ions simultaneously or by mixing one of them in a solution in which the other is present. Further, while taking into consideration the critical growth rate of silver halide crystals, halide ions and silver ions may be generated by sequentially and simultaneously adding them while controlling the pH in the mixing pot and 1) Ag.

By this method, silver halide grains having a regular crystal shape and a nearly uniform grain size can be obtained. Conversion methods can also be used to change the halogen composition of the particles after growth.

The internal latent image type silver halide emulsion used in the present invention includes:
Although there are various types as mentioned above, it is preferable to use a so-called core/shell type emulsion in which silver halide grains consist of a core and a shell covering it.

The core silver halide grains preferably mainly consist of silver bromide, and may also contain silver chloride and/or silver iodobromide (★).The silver halide grains forming the core may have any shape. For example, the grains may be hexahedral, octahedral, dodecahedral, or a mixture thereof, or may be spherical, tabular, or irregularly shaped.The average grain size of the silver halide grains constituting the core Although the particle size distribution can be varied over a wide range depending on the desired photographic performance, it is more preferable that the particle size distribution be narrow. That is, it is preferable that the silver halide grains constituting the core be substantially monodisperse. Further, the core particles may be chemically sensitized, doped with metal ions, or both, or may not be doped with both.

Further, the core may not be subjected to the above-mentioned chemical sensitization treatment or metal ion doping. In this case, it is thought that a photosensitive center is generated at the interface between the core and the shell due to crystal strain or other factors during the process of covering the core particle with the shell.
Reference can be made to the descriptions in No. 014 and No. 3,957.488.

A double jet method or a premix method can be used to form the shell on the core described above. It is also possible to form a core emulsion by mixing fine grains of silver halide and performing Ostwald ripening.

The shell may be a single layer in silver halide composition, or it may be a multilayer shell consisting of more than two layers.

The multilayer shell is composed of at least an outermost layer and a layer adjacent thereto, but may have a structure in which layers having different silver halide compositions are laminated.

Further, the multilayer shell layer may have a structure in which the silver halide composition changes continuously in the radial direction of the silver halide grains.

Further, it is preferable that silver chloride is contained in the outermost layer of the outermost shell or the surface layer of the shell,
In this case, any silver halide composition may be used as long as it substantially contains silver chloride. For example, silver chloride,
Examples include silver chlorobromide, silver chloroiodide, and silver chloroiodobromide.

In this case, the amount of silver chloride contained in the shell is preferably 30 mol% or more of the total amount of silver halide in the shell. Further, the ratio of the core to the shell is arbitrary, and the content of silver chloride contained in the core/shell type grains is preferably 20 mol % or more based on the total silver halide.

The obtained silver halide emulsion may have any grain size distribution. Therefore, emulsions with a wide grain size distribution (referred to as polydisperse emulsions) may be used, or emulsions with a narrow grain size distribution (referred to as monodisperse emulsions) may be used singly or in combination, and polydisperse emulsions and A mixture of monodispersed emulsions may be used. It can also be used by coating in different layers. Here, monodispersity in a monodisperse emulsion means that the coefficient of variation in the grain size distribution of silver halide grains contained in the emulsion is 22% or less, preferably 1.
An emulsion containing 5% or less.

Further, the particle size of particles for obtaining the above particle size distribution is expressed by the diameter in the case of spherical particles, and the diameter of a circle having an area equal to the projected area of the particles in the case of other shapes. This can be measured by electron microscopy.

The silver halide emulsion used in the present invention can be optically sensitized using commonly used sensitizing dyes. Combinations of sensitizing dyes used for supersensitizing internal latent images in silver halide emulsions, negative-working silver halide emulsions, etc. are also useful for the silver halide emulsions of the present invention. Regarding sensitizing dyes, reference may be made to Research Disclosure No. 15162.

Silver halide emulsions are prepared using commonly used stabilizers, such as compounds with an azaindene ring and heterocyclic compounds with a mercapto ring, in order to keep the surface sensitivity as low as possible, give a lower minimum density, and give more stable properties. Compound(
Representative examples include 4-hydroxy-6-methyl-1,3,3a, 7-titrazaindene and l-
Examples include phenyl-5-mercaptotetrazole. ) can be included.

Other silver halide emulsions may contain antifoggants or stabilizers, such as mercury compounds, triazole compounds,
Azaindene compounds, benzothiazolium compounds,
Zinc compounds and the like may be used.

The non-image-forming silver halide grains used in the present invention are preferably fine grains. The particle size is preferably 0.40 μm or less, more preferably 0.20 μm or less.

The halide composition is not particularly limited, but preferably contains silver chloride.

The method for producing non-image-forming silver halide may be the same as or different from that for the internal latent image type silver halide grains used in the present invention, but it is preferable to produce it by the same method.

Further, the crystal habit may be a normal crystal such as a cube, an octahedron, or a tetradecahedron, or may be an amorphous crystal.

The non-photosensitive layer containing non-image-forming silver halide grains may be a single layer or multiple layers, and the position of the non-photosensitive layer is not particularly limited.

A wide variety of compounds can be used as the fogging agent used in the present invention, and it is sufficient that the fogging agent is present during the development process. (preferably in the silveride emulsion layer), or may be contained in the developer or the processing solution prior to development. The amount used can vary widely depending on the purpose, and the preferred amount is 1-1, 500 mg5, preferably 10-1 mg per mole of silver halide when added to a silver halide emulsion layer.
．． 000IIg. When added to a processing solution such as a developer, the preferred amount is 0.01 to 5 g/α, particularly preferably 0.05 to Ig/12.

Fogging agents used in the present invention include, for example, U.S. Pat.
563.785, hydrazines described in 2,588,982, or U.S. Pat. No. 3,227.55
The hydrazide or hydrazone compound described in No. 2;
U.S. Patent No. 3,615.615, U.S. Patent No. 3,718,479
Heterocyclic quaternary nitrogen salt compounds described in US Pat. No. 3,719.494, US Pat. No. 3,734.738 and US Pat. Examples include compounds having adsorption groups on the silver halide surface, such as hydrazinophenylthioureas.

Moreover, these fogging agents can also be used in combination.

For example, RD No. 15162 describes the use of a non-adsorption type fogging agent in combination with an adsorption type fogging agent, and this combination technique is also effective in the present invention.

As the fogging agent used in the present invention, either an adsorption type or a non-adsorption type can be used, and they can also be used in combination.

Specific examples of useful fogging agents include phenylhydrazine hydrochloride, l-formyl-2-(4-methylphenyl)hydrazine, 1-acetyl-2-7enylhydrazine,
- Hydrazine compounds such as methylsulfonyl-2-(3-phenylsulfamidophenyl)hydrazine; 3-(
N-substituted quaternary cycloammonium salts such as 2-formylethyl)-2-methylbenzothiazolium bromide, 2-methyl-3-(3-(phenylhydrazino)propyl)benzothiazolium bromide; 5-(1-ethylnaphthoH,2-bl thiazolin-2-ylideneethylidene)-1-(2-phenylcarbazoyl)methyl-3-
(4-sul7amoylphenyl)-2-thiohydantoin, 5-(3-ethyl-2-penzothiazolinylidene)
-3-(4-(2-formylhydrazino)phenyl]rhodanine, 1-(4-(2-formylhydrazino)phenyl)-3-phenylthiourea, 1.3-bis(4-(
Examples include 2-formylhydrazino)phenylcothiourea.

After image exposure, the photographic light-sensitive material having a silver halide emulsion layer according to the present invention is subjected to full-surface exposure or surface development treatment in the presence of a fogging agent to directly form a positive image. This surface development processing method means processing with a developer substantially free of silver halide solvent.

Developers that can be used in the surface developer used for developing the photographic light-sensitive material according to the present invention include common silver halide developers, such as polyhydroxybenzenes such as hydroquinone, aminophenols, and 3-pyrazolidones. , ascorbic acid and its derivatives, reductones, phenylenediamines, etc., or mixtures thereof. Specifically, hydroquinone, aminophenol, N
-methylaminophenol, 1-phenyl-3-birazolitone, l-phenyl-4,4-dimethyl, -3-pyrazolidone, l-7enyl-4-methyl-4-hydroxymethyl-3-pyrazolidone, ascorbic acid, N, N
-diethyl-p-7 2-diamine, diethylamino-0-toluidine, 4-amino-3-methyl-N-ethyl-N-(β-methanesulfonamidoethyl 3-methyl-N-ethyl-N-(β -hydroxyethyl)aniline, etc. These developers can be included in the emulsion in advance and allowed to act on the silver halide during immersion in a high pH aqueous solution.

The developer used in the present invention can further contain specific antifoggants and development inhibitors, or these developer additives can be optionally incorporated into the constituent layers of the photographic material. be.

Depending on the purpose, various photographic additives such as wetting agents, film property improvers, and coating aids may be added to the silver halide emulsion according to the present invention.

Other photographic additives include gelatin plasticizers, surfactants, ultraviolet absorbers, pH adjusters, antioxidants, antistatic agents, thickeners, graininess improvers, dyes, mordants, brighteners, and developers. Speed modifiers, matting agents, etc. may also be used.

It is useful to apply the photographic light-sensitive material according to the present invention to color applications, and in this case it is preferable to include cyan, magenta and yellow dye image-forming couplers in the silver halide emulsion. As the coupler, commonly used couplers can be used, and a specific example thereof is RD-17643 (
December 1978), 18717 (November 1979)
month) can be referred to.

Among these, the magenta coupler has the following general formula (M-
A pyrazoloazole coupler represented by 1) is particularly preferred.

General Formula (M-I) In the formula, 2 represents a nonmetallic atom group necessary to form a nitrogen-containing heterocycle, and the ring formed by Z may have a substituent. X represents a hydrogen atom or a group that can be separated by reaction with a color developing agent.

Moreover, R represents a hydrogen atom or a substituent.

Specific examples of the coupler represented by the above general formula (M-1) are:
Compounds described on pages 20 to 35 of Japanese Patent Application No. 63-55490 can be mentioned.

Furthermore, it is useful to use an ultraviolet absorber to prevent the dye image from fading due to short-wavelength actinic rays.

Examples of the support for the photographic light-sensitive material according to the present invention include polyethylene terephthalate film, polycarbonate film, polystyrene film, polypropylene film, cellulose acetate film, glass, baryta paper, polyethylene laminate paper, etc., which have been subjected to undercoating as necessary. It will be done.

In addition to gelatin, suitable gelatin derivatives can be used as protective colloids or binders in the silver halide emulsion layer according to the present invention, depending on the purpose. Suitable gelatin derivatives include, for example, acylated gelatin, guanidylated gelatin, carbamylated gelatin, cyanoethanolated gelatin, and esterified gelatin.

In addition, in the present invention, other hydrophilic binders (binders) can be included depending on the purpose, and include polyvinyl alcohol, polyvinylpyrrolidone, hydrolyzed polyvinyl acetate, etc. ,
It can be added to constituent layers of a photographic light-sensitive material such as a filter layer and a backing layer depending on the purpose.Furthermore, the hydrophilic binder can contain a suitable plasticizer, lubricant, etc. depending on the purpose.

Further, the constituent layers of the photographic light-sensitive material according to the present invention can be hardened with any suitable hardening agent.

These hardeners include chromium salts, zirconiums,
Examples include aldehyde hardeners such as formaldehyde and mucohalogen acids, halotriazine hardeners, polyepoxy compounds, ethyleneimine hardeners, vinyl sulfone hardeners, and acryloyl hardeners.

The photographic light-sensitive material according to the present invention has, on a support, at least one photosensitive emulsion layer containing the internal latent image type silver halide grains according to the present invention, as well as a filter layer, an intermediate layer, a protective layer, It is possible to provide a large number of various photographic constituent layers such as subbing layers, backing layers, antihalation layers, etc.

It is particularly preferable that the photographic light-sensitive material of the present invention is used for full color use; in this case, at least one layer each of a red-sensitive silver halide emulsion layer, a green-sensitive silver halide emulsion layer,
A blue-sensitive silver halide emulsion layer and a non-light-sensitive layer containing non-image-forming silver halide grains are applied. At this time, at least one light-sensitive silver halide emulsion layer may contain internal latent image type silver halide grains according to the present invention, but all light-sensitive silver halide emulsion layers contain internal latent image type silver halide grains according to the present invention. Preferably, it contains latent image type silver halide grains. Further, each photosensitive silver halide emulsion layer may be a single layer or may consist of a plurality of layers. In the case of multiple layers, among the multiple layers,
Between the layer closest to the support and the layer furthest from the support,
It may have a non-light-sensitive layer (which may or may not contain non-image-forming silver halide grains) and other color-sensitive emulsion layers.

The photographic light-sensitive material according to the present invention can be effectively applied to various uses such as black and white general use, X-ray solubility, color use, false color use, printing use, infrared use, micro use, and silver dye bleaching use. Also, colloid transfer method, silver salt diffusion transfer method, Rogers U.S. Patent Nos. 3,087.817 and 3,185.5
67 and 2,983.606, Weyarts et al., U.S. Pat. No. 3,253,915, Whitemore et al., U.S. Pat. No. 3,227.550, Barr et al.
No. 27.551, U.S. Pat. No. 3,227 to Whitemore et al.
．． No. 552 and U.S. Pat. No. 3,415.644 to Rand et al.
No. 3,415゜645 and No. 3,415,646
It can also be applied to a color image transfer method, a color diffusion transfer method, etc. as described in No.

〔Example〕

EXAMPLES Hereinafter, the present invention will be specifically explained with reference to Examples, but the embodiments of the present invention are not limited thereto.

(Preparation of non-image forming silver halide ME-1 to ME-4) Non-image forming silver halide ME-1 was prepared in the following manner.

The aqueous solution containing ossein gelatin was controlled at 60°C, and while stirring vigorously, a silver nitrate aqueous solution (2.0M) and a potassium bromide aqueous solution (2.0M) were added to the solution using a Chondrold method.
Added at the same time by double jet method, average particle size 0.35
Silver bromide particles of μm size were obtained. During this time, a 0.5M potassium bromide aqueous solution was added to keep the pAg constant.

ME-2 to ME-4 were prepared in the same manner as ME-1 except that the composition and addition time of the halide solution added by the Chondrald double jet method were changed.

Table 1 shows the average particle size and halide composition.

Table 1 (Preparation of emulsion A) A semi-hostile silver bromide emulsion was prepared as follows.

An aqueous solution containing ossein gelatin was controlled at 70"C, and while vigorously stirring, a silver nitrate aqueous solution and a potassium bromide aqueous solution were simultaneously added to the solution using the Chondrold double jet method. An emulsion was obtained. To this emulsion were added 5 mg of sodium thiosulfate and 6 mg of gold a chloride (tetrahydrate) per mole of silver, and the mixture was heated at 75° C. for 80 minutes for chemical ripening to obtain a silver bromide core emulsion. This core emulsion was further grown by adding a silver nitrate aqueous solution and a potassium bromide aqueous solution to obtain an octahedral monodisperse core/shell silver bromide emulsion with an average grain size of 0.70 μm.After washing and desalting with water, this emulsion Chemical sensitization was performed by adding 1.3 mg of sodium thiosulfate and chloroauric acid (tetrahydrate) per mole of silver and heating at 60°C for 70 minutes to obtain an internal latent image type silver halide emulsion. .

(Preparation of emulsion B) A monodisperse silver chlorobromide emulsion was prepared as follows.

While controlling an aqueous solution containing ossein gelatin, a silver bromide seed emulsion with an average particle size of 0-11N+11, and ammonia at 40'O, an ammoniacal silver nitrate aqueous solution and a potassium bromide aqueous solution were simultaneously mixed using the Chondrold double jet method.
Further, the addition rate was 70% of the maximum addition rate at which no new silver halide nuclei were generated to obtain silver bromide core particles having an average particle size of 0.15 μm. At that time, the pti and pAg of the emulsion were controlled during addition using an aqueous potassium bromide solution and an aqueous acetic acid solution so as to obtain cubic grains.

The obtained silver bromide core emulsion was further added with an ammoniacal silver nitrate aqueous solution and an aqueous solution containing potassium bromide and sodium chloride (
KBr:NaC4-50:50 (molar ratio) was added simultaneously using the Chondrold double jet method, and the addition rate was 50% of the maximum addition rate at which new silver halide nuclei were not generated. A shell was formed until the average particle size reached 0.68 μm.

At that time, an aqueous solution containing potassium bromide and sodium chloride (in a molar ratio of KBr:Na
C (1-1:9) and acetic acid aqueous solution to adjust the pH of the emulsion.
and phg were controlled. After washing with water and desalting, gelatin was added to prepare emulsion EM-1. This emulsion was confirmed to be a monodisperse emulsion consisting of cubic grains with uniform size.

(Preparation of color sensitized emulsions A-1 to A-3) Using the emulsion A obtained above, 2.0% of blue-sensitive sensitizing dye BD-1 shown below was added per mole of silver halide. OX
A blue-sensitive emulsion A-1 was prepared by adding 10-' mole of the compound.

Similarly, green-sensitive sensitizing dye CD-1, red-sensitive sensitizing dyes RD-1 and RD-2 were added to form a green-sensitive emulsion A-2.
and red-sensitive emulsion A-3 was prepared.

RD-1 RD-1 RD-2 (Preparation of color sensitized emulsions B-1 to B-3) Using the emulsion B obtained above, the blue-sensitive sensitizing dye BD-1 was added per mole of silver halide. 2.0XlO-4
mol, silver nitrate 3.3X 10-" mol, sodium chloride. 8.96X 10-" mol added to make blue-sensitive emulsion B-
1 was prepared.

In the same manner, green-sensitive sensitizing dye GD-1, silver nitrate and sodium chloride were added to prepare green-sensitive emulsion B-2, and red-sensitive sensitizing dye RD-1, RD-2, silver nitrate and sodium chloride were added. Red-sensitive emulsion B-3 was prepared by adding sodium.

Example 1 On a paper support laminated on both sides with polyethylene,
A color photographic material with the following layer structure was prepared (Sample 1)
. Note that the numbers in the layers indicate the amount of coating (mg/d+s).

7th layer (protective layer) Gelatin 12.3 6th layer (
Ultraviolet absorption layer) Gelatin 5.4 Ultraviolet absorber (UV-1) 1.0 Ultraviolet absorber (U
V-2) 2.8 solvent (50-3)
1.2 Fifth layer (blue photosensitive layer) Blue sensitive emulsion (A-1) 5.0 Gelatin 13.5 Yellow coupler (YC-1) 8.4 Image stabilizer (A O-
3) 3.0 Solvent (SO-1) 5.2 Fogging agent (FA-1) 15.0 mg 1 mol Silver 4th
Layer (yellow filter layer) Gelatin yellow colloidal silver ultraviolet absorber (UV-1) ultraviolet absorber (UV-2) color mixing inhibitor (AS-1) solvent (So-3) 3rd layer (green photosensitive layer) green sensitivity Emulsion (A-2) Gelatin magenta coupler (MC- Image stabilizer (AO-1) Solvent (So-4) Fogging agent (FA-1) 2nd layer (color mixing prevention layer) Gelatin color mixing prevention agent (AS-1 ) Solvent (So-2) 1st layer (red-sensitive layer) Red-sensitive emulsion (A-3) Gelatin 4.2 1.0 0.5 1.4 0.4 0.8 2.7 13.0 1) 2.4 2.0 3.15 15.0 mg 1 mol silver 7.5 0.55 0.72 4.0 13.8 Cyan coupler (CC-1) 4.2 Image stabilizer (AO-3) 2.2 Solvent (So-
1) 3.3 Fogging agent (FA
-1) 15.0 mg 1 mol silver Note that 5A-1 and 5A-2 were used as coating aids, and HA was used as a hardening agent.
-1 to apply the coating.

(Additives used) A-1 C-1 So-3 C-1 AO-4 AS-1 So-i 80-1 υH SO=2 AO-3 HA-1 UV-1 Non-photosensitivity of sample 1 Samples 2 to 17 were prepared in exactly the same manner as Sample 1, except that non-image-forming silver halide was added to the layer in a coating amount of 1.0 mg/dm'' as shown in Table 2.

Table 2 UV-2 A-1 A-2 Each of the obtained samples was exposed to light using a photosensitive needle through an optical wedge, and processed in the following processing steps.

[Processing-1] Processing process Time Temperature color development
1 minute 30 seconds to 2 minutes 30 seconds 33℃ bleach fixing
Stable at 33℃ for 40 seconds
Dry at 33℃ for 3 times for 20 seconds each.
30 seconds 60-80℃ Color developer formulation Diethylenetriaminepentaacetic acid 2.0g Benzyl alcohol 12.8g Diethylene glycol 3.4g Sodium sulfite 2.0g Sodium bromide
0.5g hydroxylamine sulfate
2.6g sodium chloride
3.283-Methyl-4-amino-N-ethyl-N-
β-methanesulfonamide ethylaniline sulfate 4.25g Potassium carbonate 30.0g Fluorescent brightener (4,4'-diaminostilbendisulfonic acid derivative)
Add 1.0g water
112 (pH with potassium hydroxide or sulfuric acid)
Adjusted to 10.5. ) Bleach-fix solution formulation Ammonium thiosulfate (54wt%) 150m
ff Sodium sulfite 15g Iron(III) ethylenediaminetetraacetate Ammonium 55g Sodium ethylenediaminetetraacetate (dihydrate) 4g Glacial acetic acid 8.61g Add water 11 (Adjusted to pH 5, 4 with aqueous ammonia or hydrochloric acid) Stable liquid formulation l-Hydroxyethylidene-1,l-diphosphonic acid (60%) l, 6m
Q Bismuth chloride 0.35g Polyvinylpyrrolidone 0, 25g Aqueous ammonia 2.5mff Nitrilotriacetic acid/3Na 1.0g 5-Chloro-2-methyl-4-inthiazolin-3-one 50mg2-
Cutyl-4-isothiazolin-3-one 50mg
Optical brightener (4,4'-diaminostilbendisulfonic acid derivative) Add 1.0 g of water
lα (adjusted to pH 7.5 with potassium hydroxide or hydrochloric acid) [Processing-21 Except for adjusting the pH of the color developer to 11.0, Processing-
Same as 1.

[Processing-3] Processing-3 except that the pH of the color developer was adjusted to 11.5.
Same as 1.

The obtained images were subjected to sensitometry and the maximum density (Dmax) and minimum density (Dmin) were measured.As is clear from Table 3, the samples of the present invention had a sufficiently high maximum density even in rapid processing. It has a sufficiently low minimum density and has excellent developability.

It is also found that among the present invention, Samples 9 to 13, and furthermore Samples 14 to 18, containing preferred embodiments of non-image-forming silver halide are even more excellent in developability.

It is understood that the effect of accelerating development does not depend on the layer containing non-image-forming silver halide.

Example 2 Samples 18 to 22 were prepared in the same manner as in Example 1 except that the fogging agent (FA-1) added to the photosensitive layer was removed, with the addition of non-image forming silver halide as shown in Table 4. Created.

The non-image-forming silver halide added layer was the second layer, and the amount added was 1.0+ag/d+'', the same as in Example 1.

Each of the obtained samples was subjected to wedge exposure and development in the same manner as in Example 1, and the obtained images were subjected to sensitometry to measure the maximum density and minimum density.

However, a fogging agent (F) was added to the color developer used in Example 1.
Ig #l of A-1) was added.

From the results in Table 4 and Table 5, it can be seen that samples 19 to 20 of the present invention containing non-image forming silver halide in the second layer (color mixing prevention layer) are excellent in developability in rapid processing.

Further, Samples 21 and 22 containing the preferred non-image-forming silver halide exhibited better effects in this example as well.

Example 3 A non-image-forming silver halide was added as shown in Table 6 in exactly the same manner as in Example 1 except that color sensitized emulsions A-1 to A-3 were changed to B-1 to B-3, respectively. Samples 23 to 27 were created.

Table 6 The non-image-forming silver halide additive layer is the second layer, and the amount added is 1. Omg/dm".

Each sample was exposed and developed in the same manner as in Example 1, and sensitometry was performed. Table 7 shows the results.

From the results in Table 7, it is clear that the samples of the present invention have excellent developability in rapid processing.

Example 4 Sample 28 was prepared in the same manner as Samples 23 to 27 of Example 3, except that the fogging agent (FA-1) added to the photosensitive layer was removed, with non-image forming silver halide added as shown in Table 8. ~32 were created.

Table 8 The non-image-forming silver halide additive layer is the second layer, and the amount added is 1. Omg/dm".

Each sample was exposed and developed in the same manner as in Example 1, and sensitometry was performed. Table 9 shows the results.

It can also be seen from Table 9 that the samples of the present invention exhibited the effect of the present invention of excellent developability.

hand

Claims (1)

[Claims] at least one silver halide emulsion layer containing internal latent image type silver halide grains that have not been fogged in advance and a non-photosensitive layer containing non-image forming silver halide grains;
A direct positive silver halide photographic material characterized in that it is processed in the presence of a fogging agent.