JPS59201049A - Method for forming positive type image - Google Patents

Abstract

PURPOSE:To prevent storage stability of a photosensitive material from undergoing adverse effect by imagewise exposing a silver halide photographic element having an emulsion layer and used for forming a positive type image, and developing it in the presence of a specified compd. CONSTITUTION:A silver halide photographic element having an emulsion layer and used for forming a positive type image is imagewise exposed and developed in the presence of a fogging agent of a compd. represented by the formula shown here in which R1, R2 are each H, alkyl, cycloalkyl, aryl, -NHR3, or NHNR4R5; R3 is H, alkyl, cycloalkyl, or aryl; and R4, R5 are each H, alkyl, cycloalkyl, aryl, or acyl. A preferable amt. of said fogging agent is about 10<-6>- 10<-1> mole per mole or internal latent image type silver halide.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention can be used in photographic technology, particularly in photographic image forming methods.

The present invention relates to a method for forming a positive image, and more particularly to a method for forming a direct positive image using a capri agent.

BACKGROUND OF THE INVENTION It is well known that positive images can be formed directly using silver halide photographic materials without the need for reversal processing or negative photographic images.

Excluding special methods, the methods used to create positive images using conventionally known direct positive-type silver halide base photosensitive materials can be mainly divided into two types, considering their practical usefulness. I can do it.

One type uses a pre-coupled silver 10-genide emulsion and uses solarization or the Burschel effect to destroy fog nuclei (latent images) in exposed areas to obtain a positive image after development. .

The other type uses an unfogged internal latent image type silver halide emulsion and performs surface development after and/or during capri processing after image exposure to obtain a positive image. .

Here, the capri processing may be performed by exposing the entire surface to light, using a capri agent, using a strong developer, heat treatment, etc., but usually it is performed using a fogging agent. It is being done. The term "internal latent image type silver halide emulsion" refers to a silver halide emulsion which mainly has photosensitive nuclei inside the silver halide grains and forms a latent image inside the grains upon exposure.

This latter type of method of directly obtaining a positive image using a silver halide emulsion has generally higher sensitivity than the former type of method, and is suitable for applications requiring high sensitivity. It is related to these.

Various techniques are known in this technical field. For example, U.S. Pat. No. 2,592,250;
British Patent No. 2,456,957, British Patent No. 2,497.875, British Patent No. 2,588,982, British Patent No. 1,151,
363, JP 43-29, 405, JP 47-
No. 9,434, No. 47-9.677, No. 47-32,
No. 813, No. 47-32, 814, No. 48-9, 72
No. 7, No. 48-9,717, U.S. Special ¥3,761
, No. 266, No. 3,796,577, Japanese Unexamined Patent Publication No. 50-8
, No. 524 and No. 50-38, 525 are the main ones.

By using these known methods, it is possible to produce a relatively highly sensitive photographic material as a direct positive type.

For details on the direct positive image formation mechanism, see, for example, ``The Theory of the Photographic Process'' by Mies and Ames.
'theory of the Photography
The process by which a positive image is formed can be understood to some extent by the ``desensitizing effect of an internal latent image'' as discussed on page 161 of the 3rd edition.

In other words, Capri nuclei are selectively generated only on the surface of unexposed silver halide grains in the non-image area due to the surface desensitization effect caused by the so-called internal latent image created inside the silver halide grains by the initial image exposure. It is believed that a photographic image is formed in the unexposed areas by normal development.

Hydrazine compounds are known as useful capri agents that exhibit such selective cuffing action.

For example, U.S. Patent No. 2,563,785;
88,982, naphthylhydrazine sulfonic acid as described in U.S. Pat. No. 2,604,700, or British Patent No. 1.4.
The sulfophthylhydrazines described in No. 03,018 have been used as capri agents.

However, in order to apply the method of directly forming positive images using these compounds as capriagents to various photographic fields, there remain technical problems that must be further improved.

For example, in such fog development, the capri reaction by the fogging agent must occur prior to the development reaction, so the fat introduction period until the start of development is longer than that in normal latent image silver development. is long and its development is therefore considerably delayed. Therefore, especially when applied to multilayer color photographic materials, there are problems such as non-uniformity of properties between layers. Conventional capri agents also have a relatively low maximum final concentration.

Further, US %iff: No. 3,227,552 describes that hydrazide and hydrazine derivatives such as hydrazine compounds can be used not only in the developer but also when added to the light-sensitive emulsion layer. Examples of capri-st suitable for use in addition to the light-sensitive emulsion layer include, for example, U.S. Pat.
Quaternary salt compounds described in JP-A-53-20318 and JP-A-56-16, etc.
Acylhydrazinophenylthiourea compounds described in No. 125 have also been proposed and known.

All of the above-mentioned fogging agents are compounds that can be adsorbed onto the surface of silver halide grains, and they exhibit good fogging effects with very few addition caps.The development induction period is also relatively short, and the maximum density of images obtained. It's also expensive.

However, some of these capri agents have absorption in the visible range and cause desensitization, and even if they are colorless thiourea derivatives that have a thiourea group as an absorbing group, they can be directly used in positive photosensitive materials. This has an adverse effect on the storage stability, and has drawbacks such as changes in sensitivity and the occurrence of fog over the entire surface when the photosensitive material is stored for a long period of time.

Additionally, U.S. Patent No. 4,139,387 and Research Disclosure
osure) No. 15750 discloses thiocarbazide derivatives. This compound is also a capri agent that has a remarkable effect when added in a small amount, but it has some problems with storage stability, and the gradation of the obtained positive image is soft, making it impossible to obtain a clear image. However, it has been desired to develop a more improved capri agent.

OBJECTS OF THE INVENTION The first object of the present invention is to provide a method for forming a positive image by using a capri agent that does not adversely affect the storage stability of photosensitive materials, and the second object is to It is an object of the present invention to provide a method for forming a positive image using a capri agent, which can produce a sharp and clear image.A third object of the invention is to provide a method for forming a positive image using a capri agent, which can produce a sharp and clear image. It is an object of the present invention to provide a method for forming a positive image by using a capri agent which is highly effective and has good stability with little fluctuation during development, image processing temperature, and storage over time.

Structure of the Invention As a result of various studies, the present inventors have found that the above object is to provide a positive-tone image forming material having at least one emulsion layer made of a hydrophilic colloid containing internal latent image type silver halide grains. It has been found that this can be achieved by a method of forming a positive image in which a silver halide photographic element is subjected to imagewise exposure and then developed in the presence of a compound represented by the following general formula.

General formula % Formula % In the formula, 1 and 1 are each a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, and -NH.

(Here, R3 represents a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group.) or -N)INR4
R5 (here, kL4 and i4 each represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an acyl group.Also, R5 and R5 may be combined to form a 5- or 6-membered ring. Good.).

The present invention will be explained in more detail below.

The capri agents useful in the present invention are as shown in the general formula above, and in the general formula, 8 to R5
Each of the alkyl groups represented by may be substituted with, for example, a straight chain group having from 1 to 18 carbon atoms, a monomer group, a cyano group, etc., such as a methyl group, an ethyl group, an n-butyl group, an isopropyl group, etc. , octyl group, dodecyl group, trifluoromethyl group, W-bromobutyl group, β-methoxyethyl group, carboxyethyl group, benzyl group, phenethyl group, and the like. Again, ~ 几.

The cycloalkyl group represented by is, for example, a cyclohexyl group.

Examples of the aryl group represented by R1''kL5 include a phenyl group and a naphthyl group, but these may be further substituted with an alkyl group, an alkoxy group, a nitrogen atom, an amino group, a cyano group, a carboxyl group, etc. Commonly, for example, phenyl group, tolyl group, methoxyphenyl group,
Examples include chlorophenyl group, flobylphenyl group, acetylaminophenyl group, and carboxyphenyl group.

Furthermore, the acyl group represented by 8-tone and horse is derived from aliphatic or aromatic carboxylic acid, thiocarboxylic acid, fonic acid, or carbamic acid, such as acetyl group, formyl group, benzoyl group, etc. , phenylcarbamoyl group, methylcarb7yl group, phenylsulfamoyl group, methylsulfonyl group, 3-pyridylcarbonyl group, and the like. The most preferred compound as a capri agent according to the present invention is one in which either R1 or R2 is a hydrogen atom.

Next, a representative example of the capri agent according to the present invention having the above general formula will be given, but the present invention is not limited thereto.

(Exemplary compound) 0 111 (2) ) to INC) iNHCH 1 (7) NH2-NH-C-NHNHCONH2
000 Synthesis examples of the above-mentioned exemplary compounds according to the present invention are listed below.

Synthesis Example 1 (Synthesis of Exemplary Compound (3)) 6.5p of 4-phenyl semicarbazide was dispersed in Q[100-, 4F#
Heat refluxed between the walls. Next, the solvent was concentrated to 50% under pressure, and 50% of water was added to it to collect the crystals.
Washed with water. Yield of target product: 5.9g, melting point: 175-1
76°C Synthesis Example 2 (Synthesis of Exemplary Compound (7)) 9.5 g of carbohydrazide was not dissolved in a mixture of glacial acetic acid IQm7 and water 100%. A solution of 8.1 g of potassium cyanate dissolved in 35 g of water was added dropwise to the solution over 1 hour while cooling with water.

Thereafter, the mixture was brought back to room temperature and stirred for 5 hours. One of the resulting crystals was taken and diluted with water and ethanol. Yield of target product 11.2
g, melting point 225-227°G (decomposition) Synthesis Example 3 (Synthesis of Exemplary Compound (8)) 6.7 g of the above carbohydrazide-carboxylic acid was added to 4 ml of concentrated hydrochloric acid,
Dissolve in 50m of water. To this was added a solution of 4.5 g of potassium cyanate dissolved in 50 ml of water at once. The mixture was further stirred at room temperature for 5 hours, and the resulting crystals were collected and thoroughly washed with water and then with methanol. Yield of target product - *69g, melting point 2
27°C (decomposition) Synthesis Example 4 (Synthesis of Exemplary Compound (9)) 6.89 g of phenylhydrazide was mixed with 5.8 g of phenyl hydrazide and 5 g of chloroformamide under a stream of air.
01LtK was dissolved, 5.1 g of triethylamine was added thereto, and then N,N-dietheraminocarbonyl chloride 9.1. ! i+ was added dropwise.

After stirring at room temperature for 2 hours, the mixture was poured into ice water, and the resulting crystals were filtered once and thoroughly washed with water and then methanol.

Yield of target product: 7.09, melting point: 155-158°C According to the present invention, the capri agent of the present invention synthesized as described above can be prepared by using a developer, a processing sheet (a processing sheet is placed on top of a silver halide photosensitive material). In the case of a method in which processing is carried out by overlapping and developing a developer during the process), it may be further contained in a silver halide photosensitive material.

When the capri agent according to the present invention is contained in a silver halide photosensitive material, an emulsion layer consisting of a hydrophilic colloid containing internal latent image type silver halide grains and/or a hydrophilic colloid layer adjacent to the emulsion layer, e.g. It is preferable to include it in an intermediate layer, a protective layer, a filter layer, an antihalation layer, etc.

In the present invention, in order to exhibit the fogging effect and to shorten the development induction period, it is most preferable to incorporate the above-mentioned capricing agent into the silver halide photosensitive material.

The amount of the fogging agent used in the present invention can vary widely depending on the characteristics of the silver halide emulsion used, the type of capping agent, and the development conditions. After exposure, the amount should be enough to provide a fogging effect to obtain a positive image when developed with a bottom developer (and the amount should be enough to provide a sufficient maximum density (for example, 1.5 or more) after development). Usually, the amount of the capri agent is in the range of 10-6 mol to 10 mol, more preferably 10 mol to 10 mol, per 1 mol of internal latent image type silver halide.
It is in the order of moles. Moreover, the capri agent according to the present invention is 2
(a) or more can be used in combination, and when used in combination, it is preferable to contain them in the same hydrophilic colloid layer, but they can also be contained in separate layers.

Furthermore, when the capri agent according to the present invention is applied to a color diffusion transfer method, it can be mixed into the image-receiving layer or sheet. In this case, the content of the capri agent may be the same as in the case where it is contained in the silver halide emulsion layer.

The capri agent according to the present invention can also be used in combination with conventionally known capri agents.

Specific examples of the above conventionally known useful capri agents include hydrazine hydrochloride, phenylhydrazine hydrochloride, 4-methyl-phenylhydrozine hydrochloride, 1-formi#-2-(
4-methylphenyl)hydrazine, 1-acetyl-2-
Phenylhydrozine, 1-acetyl-2-(4〒acetamidophenyl)hydrazine, 1-methylsulfonyl-2-phenylhydrazine/, 1-pency/l/-2-
Phenylhytodidine, l-methylsulfonyl-2-(
3-phenylsulfonamidophenyl)hydrazine,
Hydrazine compounds such as formaldehyde phenylhydrazone; 3-(2-formylethyl)-2-methylbenzothiazolium bromide, 3-(2-formylethyl)-2-7"ropylbenzothiazolium bromide, 3
-(2-acetylethyl)-2-penzylpenzoselenasolium puromy)", 3-(2-acetylethyl-2
-Benzyl-5-phenylbenzene oxanetrium bromide, 2-methyl-3-(3-(phenylhydrazono)propyl)benenthiazolium bromide, 2
-methy/L/-3-[: 3-(p-)lylhydrazono)furopi/l/) thiazolium bromide, 2-methyA/-a-(3=(p-sulfophenylhydrazono) [propyl] benzothiazolium bromide,
2-Methyl-3-(3-(p-sulfophenylhydrazono)pentyl]penzothiazolium iodide, 1.2
-dihydro-3-methyl-4-phenylpyrido [2,1
-b) Benzoteazolium bromide, 1,2-dihydro-3-methy/l/-4-phenylpyrido C2,1-b
)-s-phenylbenzoxacilium bromide, 4
．． 4'-ethylenebis(l,2-dihydro-3-methylpyrido(2,1-b)be/zoteazolium bromide)
, 1,2-dihydro-3-methyl-4-phenylpyrido (2,1-b) benzoselenazolium-containing fluoride, etc.
Eternaphtho(1,2-b)thiazolin-2-ylideneetherithene)-1-(2-phenylcarpan°yl)methyl-3-(4-sulfamoylphenyl)-2-thiohydantoin, 5-( 3-Ethyl-2-penzothiazolinidene)-3-(4-(2-formylhydrazino)phenyl]rhodanine, 1-(4-(2-formylhydrazino)phenyl)3-phenylthiourea , 1,3-bis[4-(2-formylhydrinodino)phenylcothiourea, etc.] The internal latent image agent according to the present invention - A photosensitive material having an emulsion layer containing silver halide grains (hereinafter referred to as After imagewise exposure, the photosensitive material according to the present invention (referred to as the photosensitive material according to the present invention) forms a direct positive image by developing it in the presence of a capriagent. is employed, but a surface development method is preferred. This bare surface development method means processing with a developer substantially free of silver halide solvent.

Common silver halide developers that can be used in the developer of the present invention include polyhydroxybenzenes such as hydroquinone, aminopheno-AIs, 3-pyrazolidones, ascorbic acid and its visiting derivatives, reductones, and phenylene. Contains diamines, etc. or mixtures thereof. Specifically, hydroquino/, aminephenol, N-methylaminophenol, 1-phenyl-3-virasoliton, l-pheni/l/-4,4-dimethyl-3-pyrazolidone, 1-phenyl-4-methyl-4 -Hydroquikumethyl-3-pyrazolidone, ascorbic[,N,N-diethyl-p-phenylenediamine, diethylamino-0
-Toluidine, 4-amino-3-methylhethyl-
He (β-methanesulfonamidoethyl)aniline,
Examples include 4-amino-3-methyl-he-etherhe (β-hydroxyethyl) 7=phosphorus. These developers may 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 solution used in the present invention may further contain an amount of an antifoggant and a development inhibitor, or these developer additives may optionally be incorporated into the layer of the halogenated photosensitive material. It is also possible. Commonly useful antifoggants include benzotriazoles such as 5-methylbenzotriazole; benzothiazoles;
Included are heterocyclic thiones such as 1-phenyl-5-mercaptotetrazole; aromatic and aliphatic mercapto compounds, and the like. The developer may also contain a development accelerator such as a polyalkylene oxide spinner or a quaternary ammonium salt compound.

The light-sensitive material according to the present invention comprises an emulsion containing at least one layer of internal latent image type silver halide grains.

The emulsion containing internal latent image type silver halide grains in BA according to the present invention (hereinafter referred to as the emulsion according to the present invention) mainly forms latent images inside the silver halide grains, and most of the photosensitive nuclei are absorbed into the grains. It is an emulsion having silver halide grains inside the emulsion, and includes any silver halide such as silver bromide, silver chloride, silver chlorobromide, silver iodobromide, silver chloroiomonide, and the like.

Particularly preferably, the emulsion is prepared by exposing a portion of a sample coated on a transparent support to a light intensity school for a defined period of time up to about 1 second to obtain only a surface image of the grains substantially free of silver halide solvent. The following surface developer A to develop
Another part of the same emulsion sample is exposed in the same way and developed for 4 minutes at 20°C with internal developer B, which develops the image inside the grains. It indicates a maximum density not greater than 115 of the maximum density obtained. Preferably, the maximum density obtained with surface developer A is 1/1 of the maximum density obtained with internal developer B.
/10.

Surface developer A Metol 2.5g L-ascorbic acid 10F NaBO・4H0359 2 KBr II I! add water
1! Internal developer B Metol 2.0g Sodium sulfite (anhydrous) 90. O,! 7 Hydroquinone 8. Of! i + carbonate - carbonate border water salt 2.5. p KBr 5.0J9KI
O, add 5g water 1
Furthermore, the emulsions according to the present invention include those prepared by various methods. For example, the conversion silver halide emulsions described in U.S. Pat. No. 2,592,250, or U.S. Pat.
17,322 and 3,367,778, or the silver halide emulsions having internally chemically sensitized silver halide grains as described in U.S. Pat.
157, 3,447,927 and 3,5
A silver halide emulsion having silver halide grains containing polyvalent metal ions as described in No. 31,291;
or a silver halide emulsion in which the grain surface of silver halide grains containing a doping agent is weakly chemically sensitized as described in U.S. Patent No. 3,761,276, or
No. 8524, No. 50-38525 and No. 53-24
Silver halide emulsion consisting of grains having a laminated structure, etc. JP-A-52-156614
and silver halide emulsions described in JP-A-55-127549.

Furthermore, the emulsion according to the present invention may contain stabilizers that are commonly used at °C, such as compounds having an azaintene ring and nitrogen-containing heterocyclic compounds having a mercapto group (typical examples include 4-hydroxy-6-methyl- 1, 3, 3a,
7-titrazaindene and 1-phenyl-5-mercaptotetrazole), etc., in a range of 1711p to 10y per mole of silver halide, a lower minimum concentration and more stable results can be obtained.

In the invention, for example, mercury compounds, triazole compounds, azaindene compounds, benzothiazolium compounds, zinc compounds, etc. can be used as anti-capri agents or stabilizers.

Various photographic additives may optionally be added to the emulsion according to the present invention. For example, optical sensitizers that can be used in the present invention include cyanines, merocyanines, trinuclear or sclerotial merocyanines, trinuclear or sclerotial cyanines, steryls, holoporacyanines, hemicyanines, oxonols, etc. These optical sensitizers include basic groups such as thiazoline and thiazole, or rhodanine, thiohydantoin, oxazolidinedione, barbylic acid, and thiobarbylic acid as part of their structure as a nitrogen-containing heterocyclic nucleus. , pyrazolone, etc., and such a nucleus may be substituted with □alkyl, hydroxyalkyl, sulfoalkyl, carboxyalkyl, halogen, phenyl, cyan, or alkoxy, and may not be fused with a carbocyclic or heterocyclic ring. Optional.

The emulsions according to the invention can be supersensitized.

For information on the method of supersensitization, see, for example, ``Overview of the mechanism of supersensitization'' by Kenop Supersensitization.
(Review of 5upersensitiz
ation) Photographic Science and Engineering (Photographic 5
science and Engineering ) V
ol, 18, p. 4418 (1974).

In the invention, additives used depending on the purpose include, for example, dihydroxyalkanes as wetting agents, and alkyl acrylates as membrane property improvers. < is a water-dispersible material obtained by emulsion polymerization of a copolymer of alkyl methacrylate and acrylic acid or methacrylic acid, styrene-maleic acid copolymer, styrene-maleic anhydride-farkyl ester copolymer, etc. Particulate polymeric substances are suitable, and coating aids include, for example, saponin, polyethylene glycol lauryl ether, and the like. Other photographic additives include gelatin plasticizers, surfactants,
UV absorbers, PN adjusters, antioxidants, antistatic agents,
It is optional to use thickeners, graininess improvers, dyes, mordants, brighteners, development rate regulators, matting agents, and the like.

The silver halide emulsion prepared as described above is coated on a support via a subbing layer, anti-nolation layer, filter layer, etc. as necessary, to produce an internal latent image type silver halide photosensitive material. get.

The silver halide photosensitive material according to the present invention can be used for color photosensitive materials, and in this case it is preferable to include the holes. The above-mentioned yellow dye-forming coupler is a benzoylacetanilide type, a bivaloylamotanilide type, or a two-equivalent type in which the carbon atom at the coupling position is substituted with a substituent that can be separated during the coupling reaction, a so-called split-off group. Yellow couplers and the like are useful. As the maze/red dye-forming coupler, pyrazolone type, pyrazolotriazole type, pyrazolinopenzimidazole type, inodasilon type, or two-equivalent type magenta couplers having a split-off group are useful. Furthermore, as cyan dye-forming couplers, phenolics,
Useful are naphthol type, vilazoquinazolone type, or two-equivalent type cyan couplers having a split-off group.

In the present invention, it is useful to use ultraviolet absorbers, such as thiazolidone, benzotriazole, acrylonitrile, and benzophenone compounds, in order to prevent fading of dye images due to short-wavelength actinic rays. 326, 327, and 328 (all of which are advantageous for use alone or in combination with Ciba-Geigy 11i).

Any support can be used for the photosensitive material according to the present invention, but typical supports include polyethylene terephthalate film, polycarbonate film, polystyrene film, polypropylene film, and cellulose acetate film, which are subbed-treated as necessary. Includes films, glass, baryta paper, polyethylene laminate paper, etc.

In addition to gelatin, the light-sensitive material according to the present invention may contain a suitable gelatin derivative depending on the purpose. Suitable gelatin derivatives include, for example, acylated gelatin, guanidylated gelatin, force/l/bamylated gelatin, cyanoethanolated seratin, and esterified gelatin.

In addition, in the present invention, other hydrophilic binders can be included depending on the purpose, and examples of suitable binders include colloidal albumin, agar, in addition to gelatin.
Cells such as gum arabic, dextran, alginic acid, cellulose acetate hydrolyzed to 10-20% acetyl content (such as ff-s derivatives, polyacrylamide, imidized polyacrylamide, casein, vinyl alcohol-vinylamino acetate copolymer) Vinyl alcohol polymers containing urethane carboxylic acid groups or cyanoacetyl groups, polyvinyl alcohol, polyvinylpyrrolidone, hydrolyzed polyvinyl acetate, polymers obtained by Togane of proteins or saturated acylated proteins and monomers having vinyl groups, polyvinylpyridine, Contains polyvinylamine, polyaminoether methacrylate, polyethylene amine, etc., and can be added to constituent layers of silver halide photosensitive materials such as emulsion layers, intermediate layers, protective layers, filter layers, and backing layers depending on the purpose. Furthermore, the hydrophilic binder may contain a suitable plasticizer, lubricant, etc. depending on the purpose.

Further, the above-mentioned constituent layers according to the present invention can be hardened with any suitable hardening agent. These hardeners include chromium salts, zirconium salts, aldehydes such as formaldehyde and mucohalogen acids, halotriazine,
Examples include polyepoxy compounds, ethyleneimine hardeners, vinyl sulfone hardeners, and acryloyl hardeners.

Furthermore, in the light-sensitive material according to the present invention, a large number of various photographic constituent layers such as an emulsion layer, a single filter layer, an intermediate layer, a protective layer, a subbing layer, a backing layer, and an antihalation layer can be provided on the support. It is possible.

In addition to the above-mentioned color photosensitive materials, the photosensitive materials of the present invention can be used for black and white general use, X-ray use, false color use, printing use, infrared use, micro use, silver dye bleaching use, color diffusion transfer photography, etc. It can be applied to the following uses.

Among them, it is particularly effective for diffusion transfer photography using a DRR compound. The DRR compound (dye releasing redox compound Dye Releasing Rec
iox compound) is, for example, a ballasted phenol (or naphthol) with a dye bound to the ortho or para position via a sulfonamide, or a dye bound to the 3-position of an indole via a sulfonamide. These are compounds that have the property of reacting with the oxidized form of the phenidone conductor during development, undergoing cross-oxidation, and then being hydrolyzed to release a diffusible dye. (Unexamined Japanese Patent Publication No. 48-33826, 51-104
No. 343, No. 54-130122, No. 57-8505
(Refer to No. 5, etc.) When these compounds are used and the dye released during development is received at the image receiving area and an image is formed there, a dye image is obtained only in the areas where silver development has occurred. . In other words, a negative image can be obtained with a commonly used silver halide emulsion having a surface latent image, but a positive image can be obtained with an internal latent image type □ emulsion according to the present invention.

Hereinafter, the present invention will be illustrated by examples, but the embodiments of the present invention are not limited thereto.

Example 1 A silver chloroiodobromide emulsion of internal latent image type prepared by a conversion method according to the method described in Example 1 of U.S. Pat. Adding the magenta coupler 1-(2,4,6-)lichlorophenyl)-3-(2-1′rollo-5-octadecylsuccinimidoanilino)-5-pyrazolone dissolved in an aqueous gelatin solution, Further, among the capri agents according to the present invention, exemplary capri agents 2.3.7.8
Detailed emulsion 11 was dissolved in methanol in the amount shown in Table □1 below and added to an emulsion. At the same time, samples to which the following comparative fogging agents and (1) were added as conventionally known capri agents were also prepared and used as comparative samples.

(%Kai No. 53-20318) (Comparative Capri Agent-B) (U.S. Patent No. 4,139,387)
Storage for 4 days (set as condition-1), temperature 55°C, storage without humidity control for 4 days (set as condition-2), temperature 40°C, relative humidity 80
% for 4 days (referred to as condition -3), imagewise exposure was applied, and development processing was performed according to the processing method described above.

Processing: Color development (3 minutes 30 seconds) - Stop (30 seconds) - Bleach fixing (
1 minute 30 seconds) - Water washing (1 minute 30 seconds) The treatment temperature was 30° C. in each treatment step, and the composition of each treatment liquid is shown below.

Color developer: Stop liquid 2 Finish with 1 water to 1-e.

Bleach-fix solution: The results obtained are shown in Table 1 below.

As shown in the above table, the samples using the capri agent of the present invention yielded good positive images, and also showed significantly excellent storage stability at high temperatures and high humidity. On the other hand, in the case of samples using comparative capri agents, the minimum concentration increases dramatically when stored at high temperatures (condition-2), and the maximum concentration increases when stored at high humidity (condition-3). Concentration decreases significantly.

Example 2 A photographic film was produced by the method described in Example 1 without containing a capri agent in the silver halide emulsion. That is, a protected dispersed magenta coupler was added to an internal latent image type silver chloroiodobromide emulsion, and the amount of coated silver was 20.
It was coated and dried on a cellulose acetate film support so as to give m9/1 oocm2, and after wedge exposure, it was developed with the developer used in Example 1 at 20° C. for 5 minutes. However, the developer solution contained a capri agent according to the present invention in accordance with the description in Table 2 below.

At the same time, known capri agents for comparison include phenylhydrazine (comparative capri agent C) described in U.S. Pat.
1-formyl-2-phenylhydrazine (comparative capri agent D) and l-acetylhydrazine described in No.
Developers to which phenylhydrazine (comparative capri agent E) was added were also prepared and developed. The results of the photographic properties of the obtained positive images are shown in Table 2 below.

Table 2 The results in the above table also show that even when the capri agent according to the present invention is used in a developing solution, the amount used is small compared to the conventional known comparative capri agent, and the amount of the capri agent used is relatively low. It was found that excellent fogging effects were exhibited even at pH, and good positive images with high maximum image density and low minimum density could be obtained.

Effects of the Invention A silver halide photograph for positive image formation having an emulsion layer containing internal latent image type silver halide grains is developed in the presence of a capri agent according to the present invention after exposure. According to the positive image forming method, a good positive image with a high maximum density can be obtained, and the storage stability of the photosensitive material can be significantly improved.

Agent Yoshimi Kuwahara

Claims (1)

[Scope of Claims] After imagewise exposure of a silver halide photographic element for positive-working imaging having at least one emulsion layer consisting of a hydrophilic colloid comprising internal latent image portion silver halide grains, A method for forming a positive image, comprising developing in the presence of a compound represented by the general formula. General formula [In the formula, Tame and Toshi are a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, respectively, -NHK. (Here, the world represents a hydrogen atom, an alkyl group, a cycloalkyl group, or an aryl group.) or -NHNR4Rs
(Here, 几 and 几 each represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, or an acyl group. Also, 几4 and R5 may be combined to form a 5- or 6-membered ring.) to destroy. ]