JP2001235820A - Silver halide photographic sensitive material and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a silver halide photographic sensitive material having high sensitivity and low fog and giving an image excellent in distinguishability even in a subject with parts different from each other in the degree of X-ray absorption and an image forming method using the sensitive material. SOLUTION: In the silver halide photographic sensitive material with at least two silver halide emulsion layers on each of both faces of the transparent base, the silver halide emulsion layers on the base sides contain an emulsion containing iridium compound-containing silver halide grains and at least one of the silver halide emulsion layers situated farther from the base contains an emulsion containing silver halide grains surface-converted with fine AgI grains.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silver halide photographic material and a method for forming a radiation image using the same.

[0002]

2. Description of the Related Art Normally, X-ray photographs for medical diagnosis and non-destructive inspection for photographing a subject having a low X-ray transmittance are provided by:
X-ray photography is carried out by sandwiching a silver halide photographic light-sensitive material having silver halide emulsion layers coated on both sides of a transparent support between a pair of (front and back) radiation intensifying screens. Radiation intensifying screens absorb X-rays and gamma rays,
It emits electromagnetic radiation that can be absorbed by the silver halide emulsion layer, thereby reducing the X-ray or gamma dose to the subject.

One of the problems of X-ray photography relates to the fact that the degree of X-ray absorption of a target object differs depending on the region to be photographed. For example, in a chest radiograph, the heart region has an absorption 10 times higher than the lung region, and in such a region, a low-contrast radiograph is required for imaging of a high X-ray absorption region such as the heart region. Suitable for photography, low X like lung area
A high-contrast radiographic image is suitable for imaging the line absorption region. However, taking two different radiographs to take a chest radiograph requires an increase in the amount of X-ray exposure to the target subject. Therefore, it is important to obtain an image suitable for diagnosis of the heart and lung regions by one imaging.

[0004] Normally, when taking images of both the heart region and the lung region, it is often the case to use radiographs with an expanded latitude. By using a silver halide emulsion having a polydispersed silver halide grain size, the latitude can be relatively widened. However, even with such a method, the average contrast was low, and it was not possible to provide a sensitivity curve with excellent discrimination in the lung region.

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a high sensitivity, low fog, and a chest such as a heart region and a lung region having different degrees of X-ray absorption such as lung regions. An object of the present invention is to provide a silver halide photographic material and an image forming method which provide an image having excellent discrimination even in a subject.

[0006]

The object has been attained by the following means. (1) In a silver halide photographic material having at least two silver halide emulsion layers on both surfaces of a transparent support, the silver halide emulsion layer on the support side contains silver halide grains containing an iridium compound. An emulsion containing at least one silver halide emulsion layer remote from the support with respect to the silver halide emulsion layer;
A silver halide photographic light-sensitive material containing an emulsion containing silver halide grains whose surface has been converted by fine I grains. (2) The silver halide photographic material as described in (1) above, wherein the silver halide emulsion layer on the support side is an emulsion containing silver halide grains whose grain surfaces have been converted by KI. (3) A bluing dye is contained in at least one of the silver halide emulsion layers in an amount of 1.5 mg / m ² or more and 5.0 mg / m ² or less as shown in the coating amount per 1 m ² of one side of the support. 1)
Or the silver halide photographic material according to (2). (4) The silver halide photographic light-sensitive material as described in any one of (1) to (3) above, further comprising an undercoat layer containing a solid-dispersed dye that can be decolorized in the course of development processing on at least one surface of the support. (5) Using the silver halide photographic light-sensitive material according to any one of the above (1) to (4), arranging a radiographic intensifying screen so as to sandwich both sides of the silver halide photographic light-sensitive material, In the method of exposing and forming an image,
The radiation intensifying screen has a plurality of phosphor layers formed from a coating solution containing a phosphor on a support, and a radiation intensifying screen having a protective layer thereon, wherein at least the phosphor layer An image forming method in which two layers each contain a phosphor having a different average particle diameter, and the phosphor of the phosphor layer on the support side has a smaller average particle diameter than that of the phosphor layer on the protective layer side.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. The silver halide photographic light-sensitive material of the present invention has at least two silver halide emulsion layers on both sides of a support, respectively. The silver halide emulsion layer on the support side (hereinafter referred to as a lower emulsion layer) is an iridium compound. And at least one silver halide emulsion layer (hereinafter, referred to as an upper emulsion layer) farther from the support than the emulsion containing silver halide grains (hereinafter, referred to as a lower emulsion layer). Ag
An emulsion containing silver halide grains whose surface has been converted by I fine grains (hereinafter referred to as an upper layer emulsion).

The silver halide emulsion layers are provided on both sides of the support.
In general, two layers are provided to satisfy the above relationship, but three or more layers may be provided on both surfaces. Further, in terms of manufacturing, it is preferable that the number of layers on both surfaces be the same.

As described above, by providing the lower emulsion layer and the upper emulsion layer together, even in a radiographic image in which the latitude is widened, an image having low discrimination and high sensitivity can be obtained with excellent discrimination due to appropriate contrast. can get.
Therefore, the photosensitive material of the present invention is suitable for imaging a subject having a different degree of X-ray absorption depending on the imaging site. For example, in a chest radiographic image, an image suitable for diagnosis of a heart and lung region can be obtained by one imaging. be able to.

On the other hand, when the above-mentioned emulsion is not used, the sensitivity is lowered even if the other components are the same as those of the present invention. On the other hand, if silver halide grains containing an iridium compound are not used in the lower emulsion layer, the contrast is reduced,
Fog also tends to rise. In addition, Ag was added to the upper emulsion layer.
If no silver halide grains whose surface is converted by I fine grains are used, the sensitivity is reduced. On the other hand, if the lamination order is reversed, the contrast is increased, but the sensitivity is lowered.

The iridium compound applicable to the lower emulsion of the present invention includes a water-soluble iridium compound. For example, iridium (III) halide compounds,
In addition, iridium halide (IV) compounds, and iridium complex salts having a ligand such as halogen, amines, oxalato and the like, specifically, iridium bromide,
Hexachloroiridium (III) or (IV) complex salts, hexaammineiridium (III) or (IV) complex salts, and trioxalatoiridium (III) or (IV) complex salts. In the present invention, among these compounds, II
I-valent and IV-valent compounds can be used in any combination. These iridium compounds are used after being dissolved in water or a suitable solvent. However, a method generally used to stabilize the solution of the iridium compound, that is, a hydrogen halide aqueous solution (for example, hydrochloric acid, bromic acid, hydrofluoric acid, etc.) Or an alkali halide (eg, KCl, N
aCl, NaBr, etc.) can be used. Instead of using water-soluble iridium, it is also possible to add and dissolve another silver halide grain doped with iridium in advance during the preparation of the silver halide grain.

The silver halide grains containing the iridium compound are prepared in the presence of the iridium compound. The addition of these iridium compounds can be appropriately performed during the production of a silver halide emulsion and at each stage before coating the emulsion. Preferably it is incorporated.

The total content of the iridium compound according to the present invention is 1 to 1 mol per mol of silver halide finally formed.
0 ^-9 mol or more, is suitably particularly 5 × 10 ^-9 ~1 × 10 ^-4 mol, preferably 1 × 10 ^-8 ~1 × 10 ^-5 mol, and most preferably 5 × 10 ^-7 ~5 × 10 ^-5 mol.

The lower layer emulsion of the present invention is preferably used by converting the emulsion surface with KI to enhance the dye adsorption. To convert the particle surface with KI,
It can be performed by adding a KI aqueous solution to the base particles.

The conversion amount by KI is preferably 0.01 mol% to 3 mol% based on the total silver amount. Especially 0.
A range of 0.01 mol% to 0.6 mol% appears to be preferred, but a more preferred range is 0.01 mol% to 0.3 mol%. The amount of silver iodide on the grain surface can be determined by ESCA (photoelectron spectroscopy) or the like.

The AgI fine particles which can be used in the upper layer emulsion of the present invention may have a regular crystal form such as a cubic, octahedral or tetradecahedral form, or may have a crystalline form such as a spherical or tabular form. It may be. Since the size of the AgI fine particles needs to be converted on the surface of the base particles by dissolution, the average sphere equivalent diameter is 0.
Those having a size of from 01 μm to 0.1 μm are preferred. More preferably, it is 0.02 μm or more and 0.08 μm or less. The average equivalent sphere diameter here is an average diameter when the particles are viewed as a sphere. The conversion of the grain surface by the AgI fine particles occurs when they coexist with the silver halide grains serving as the base, and the AgI fine particles dissolve at 40 ° C. or higher and come into contact with the base grains to cause conversion.
Therefore, the timing of adding the AgI fine particles of the present invention may be any time before the end of the chemical sensitization and before the end of the desalting and washing step, as long as after the formation of the particles. The pAg at the time of addition is preferably 8.5 or less, more preferably 8.4 or less. A
The amount of conversion by gI fine particles is
0.01 mol% to 3 mol% is preferred. In particular, it is preferably 0.01 mol% to 0.6 mol%, more preferably 0.1 mol%.
It is from 0.01 mol% to 0.3 mol%. The amount of silver iodide on the grain surface can be determined by ESCA (photoelectron spectroscopy) or the like.

The silver halide grains of the upper emulsion and the lower emulsion of the present invention can be prepared by a known method.
That is, any method such as an acidic method, a neutral method, and an ammonia method may be used, and a method of reacting a soluble silver salt and a soluble halide salt may be any one of a single-sided mixing method, a double-mixing method, and a combination thereof. Good. As one type of the double jet method, pA in the liquid phase in which silver halide is formed
A method of keeping g constant, that is, a control double jet method can be used. This method is preferable as a preparation method for narrowing the particle size distribution.

A monodisperse emulsion can be used as the upper emulsion or the lower emulsion of the present invention. Methods for producing monodisperse emulsions are known, and are described, for example, in J. Photo. Sci., 12, 242-251 (1).
963), JP-B-48-36890, JP-B-52-1
No. 6364, JP-A-55-142329, JP-A-57-142329
Techniques described in -179835 can be used as appropriate.

Silver halide, silver bromide, silver iodide and a mixed crystal of each combination can be selected as the halogen composition of the silver halide grains of the upper emulsion and the lower emulsion of the present invention. For example, it may be composed of silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver iodochlorobromide or the like. The emulsion of the present invention has a core
It may be a shell type emulsion. The core-shell type emulsion is known from JP-A-54-48521.

The upper and lower emulsions of the present invention can provide good results using silver halide grains having an average projected area circle equivalent diameter in the range of preferably 0.2 to 3 μm, more preferably 0.3 to 1.5 μm.

The silver halide grains of the upper and lower emulsions of the present invention may have a regular crystal form such as a cubic, octahedral or tetradecahedral form, or may have a crystal form such as a spherical or tabular form. It may be. In the present invention, it is preferable to use tabular silver halide grains, and the aspect ratio to the total projected area of the silver halide grains contained in the photosensitive silver halide emulsion layer is from 2 to 30. The ratio of the sum of the projected areas of the tabular grains is preferably from 50% to 100%, and most preferably from 80% to 100%. The average aspect ratio of the tabular silver halide grains contained in the photosensitive silver halide emulsion layer is preferably 3 or more and 20 or less. Here, the average of the aspect ratio is a value obtained by dividing the average of the projected area circle equivalent diameters of the tabular grains by the average of the thickness of the tabular grains.

The tabular silver halide emulsion was prepared by using Cug (Cug).
nac) and Chateau “Evolution of the Morphology of Physically Ripened Silver Bromide Crystals (Evolution of the Morphology of Silver Promide Crystals Dualing Physical Ripping)” E Industrie Photography, 33
Vol. 2, No. 2 (1962), pp. 121-125, Duffin, "Phatographic emulsion chemistry", Focal Press, New York, 196.
6 years, p. 66 to p. 72, APH Trivell
i), WF Smith, Photographic Journal, 80, 285 (19
Forty-six years), Japanese Patent Laid-Open No. 58-1279.
No. 27, JP-A-58-113927, JP-A-58-1
13928, JP-A-63-151618, JP-A-6-151618
It can be easily prepared by referring to the methods described in JP-A-2-115435, JP-A-6-43605 and JP-A-6-43606. Also, pBr1.3
A seed crystal in which tabular grains are present in an amount of 40% or more by mass is formed in an atmosphere having a relatively low pBr value described below, and the seed crystal is grown while simultaneously adding silver and a halogen solution while maintaining the same pBr value. It can be obtained by: In this growth process, it is desirable to add a silver and halogen solution so that no new crystal nuclei are generated. The size of the tabular silver halide grains can be adjusted by controlling the temperature, selecting the type and amount of the solvent, and controlling the addition rate of the silver salt and halide used during grain growth.

The silver halide grains of the upper and lower emulsions must be sensitive to the intensifying screens used together. Since a normal silver halide emulsion is sensitive to light in the range of blue light to ultraviolet light, the light emitted from the intensifying screen is in the range of blue light to ultraviolet light (for example, sensitized screen). This corresponds to the case where a calcium tungstate phosphor is used as the phosphor of the screen.)
For example, when a sensitizing screen using a terbium-activated cadolinium oxysulfide phosphor that emits light having a main wavelength of 545 nm is used, the silver halide of the photosensitive material is spectrally sensitized to green. There is a need. As such a spectral sensitizing dye, various spectral sensitizing dyes known to those skilled in the art can be used. Examples of such spectral sensitizing dyes are polymethine dyes including cyanine, complex cyanine, merocyanine, complex merocyanine, oxonol, hemioxonol, styryl, merostyryl and streptocyanin. Examples of spectral sensitizing dyes include, for example, U.S. Pat. Nos. 3,522,052 and 3,61.
9,197, 3,713,828, 3,61
5,643, 3,615,632, 3,61
7,293, 3,628,964, 3,70
No. 3,377, No. 3,666,480, No. 3,66
7,960, 3,679,428, 3,67
Nos. 2,897, 3,769,026, 3,55
6,800, 3,615,613, 3,61
5,638, 3,615,635, 3,70
5,809, 3,632,349, 3,67
Nos. 7,765, 3,770,449 and 3,77
0,440, 3,769,025, 3,74
5,014, 3,713,828, 3,56
7,458, 3,625,698, 2,52
6,632, 2,503,776, JP-A-48-48
No. 76525, Belgian Patent No. 691,807 and the like. The amount of the sensitizing dye to be added is preferably 200 mg or more and 1000 mg or less, more preferably 300 mg or more and 500 mg or less per 1 mol of silver halide. The spectral sensitizing dye may be added at any step in the production of the photosensitive material, but is preferably before chemical sensitization.

The silver halide grains of the upper layer emulsion and the lower layer emulsion are formed by cadmium salt, zinc salt, lead salt, thallium salt, iridium salt or its complex salt, rhodium salt or its complex salt during silver halide grain formation or physical ripening. An iron salt or an iron complex salt may coexist.

The silver halide grains of the upper and lower emulsions may be chemically and optically sensitized by a known method. Chemical sensitization methods include sulfur sensitization, selenium sensitization, reduction sensitization with complex salts and polyamines, gold sensitization with gold compounds, and sensitization with metals such as iridium, platinum, rhodium, and palladium. A known method such as can be used. These may be used in combination as needed. In particular, the sulfur sensitization method using a sulfur-containing compound and / or the selenium sensitization method using a selenium-containing compound are preferably performed in the presence of a compound that adsorbs to silver halide. The compound adsorbed on silver halide as used herein means a spectral sensitizing dye or a photographic stabilizer, and is described in JP-A-63-305343 and JP-A-1-77.
No. 047 and the like.

The emulsion layer of the present invention contains 1.
It is preferable to contain 0 × 10 ⁻³ mol or more and 2.0 × 10 ⁻² mol or less of a thiocyanate compound. The thiocyanic acid compound may be added in any process of grain formation, physical ripening, grain growth, chemical sensitization and coating, but is preferably added before chemical sensitization. As the thiocyanate compound used during the preparation of the silver halide emulsion in the present invention, a water-soluble salt such as a metal thiocyanate or an ammonium salt can be generally used. Care should be taken to use a metal element that does not affect, and potassium and sodium salts are preferred. Also, Ag
A sparingly soluble salt such as SCN may be added in the form of fine particles. In this case, the average size of the AgSCN fine particles is preferably 0.2 μm or less, particularly preferably 0.05 μm or less.

The photographic emulsion used in the present invention may contain various compounds for the purpose of preventing fog during the production process, storage or photographic processing of the photographic material, or stabilizing photographic performance. . That is, thiazoles such as benzothiazolium salts, nitroimidazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles, mercaptobenzothiazoles, mercaptobenzimidazoles, mercaptothiadiazoles, aminotriazoles , Benzotriazoles, nitrobenzotriazoles, mercaptotetrazole (especially 1-phenyl-5-mercaptotetrazole)
Mercaptopyrimidines; mercaptotriazines; thioketo compounds such as oxadolinthione; azaindenes such as triazaindenes and tetraazaindenes (especially 4-hydroxy-6-methyl (1,3,3a, 7) Many compounds known as antifoggants or stabilizers, such as tetraazaindenes, pentaazaindenes and the like can be added. For example, U.S. Patent Nos. 3,954,474 and 3,982,947,
Those described in JP-A-52-28660 can be used. One of the preferred compounds is a compound described in Japanese Patent Application No. 62-47225. Antifoggants and stabilizers before particle formation,
During particle formation, after particle formation, water washing step, at the time of dispersion after water washing,
It can be added according to the purpose at various times before, during, after chemical sensitization and before coating.

The silver content of the light-sensitive material of the present invention is preferably from 0.5 g / m ^{2 to} 2.5 g / m ² (total coated silver amount per m ² of the light-sensitive material), and more preferably 1 g / m ^2. m ^{2 to} 2.3 g / m ² .

The X-ray diagnostic image having a yellow tint gives an observer an unpleasant impression. Therefore, in general, silver halide photographic light-sensitive materials for medical use often use a so-called toning agent to adjust the color tone of developed silver. As the color tone agent, for example, a certain kind of mercapto compound is used. However, when such a conventionally well-known toning agent is applied to an emulsion containing high-sensitivity silver halide grains as in the present invention, a remarkable desensitizing effect is easily caused. In such a case, JP-A-60-15425
No. 1, JP-A-62-276539, JP-A-61-285445, JP-A-5
As described in -204085, it has been widely practiced to adjust the color tone by incorporating a substantially water-insoluble bluing dye in the light-sensitive material so that the developed silver color becomes neutral black. I have. Also, JP-A-4-34035, JP-A-7-
199394 and EP 655645A1 disclose that a bluish pigment is contained in a light-sensitive material to adjust the developed silver tone and to improve the residual color after processing with a spectral sensitizing dye. . In the present invention, too, from the viewpoint of fixability of a bluing dye in a silver halide photographic light-sensitive material, in order to eliminate contamination to a fluorescent intensifying screen, an automatic developing machine, and the like, and further to maintain high sensitivity, The seasoning dye is preferably contained in the intermediate layer or the silver halide emulsion layer below the surface protective layer, and it is more preferable that the silver halide emulsion layer contains a bluing dye, particularly in the lower silver halide emulsion layer. It preferably contains a bluing dye.

The maximum absorption wavelength of such a bluing dye is
It is preferably from 570 to 650 nm, more preferably from 580 to 640 nm.

The bluing dyes which can be used in the present invention are those which are insoluble in water and can be present as dyes in the photographic material even after development, and include pyrazolol dyes, anthraquinone dyes, azo dyes, azomethine dyes and indoanilines. Among dyes, oxonol dyes, carbocyanine dyes, styryl dyes, triphenylmethane dyes and the like, those having a maximum absorption wavelength of 570 nm to 650 nm, more preferably 580 to 640 nm are used. In this specification, the maximum absorption wavelength of a dye means the maximum absorption wavelength in a state where the dye is present in a light-sensitive material. Among the bluing dyes described above, considering the effects on the photographic properties such as safety against development processing, light fastness and desensitization, fog and stain, pyrazolol dyes, anthraquinone dyes, azo dyes, azomethine dyes, and indoaniline dyes Among them, preferred ones are used. More preferred are a pyrazolol dye and an anthraquinone dye. Specific examples of the bluing dye used in the present invention are shown below.

[0032]

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[0033]

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[0034]

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[0035]

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The bluing dye used in the present invention can be added by being dispersed by various known methods, for example, the following methods (1) to (7).

(1) A method of directly dissolving or dispersing a bluing dye in an emulsion layer or a hydrophilic colloid layer, or
After dissolving or dispersing in an aqueous solution or a solvent, a method used for an emulsion layer or a hydrophilic colloid layer can be applied. Suitable solvents, for example, methyl alcohol, ethyl alcohol, propyl alcohol, methyl cellosolve,
-9715, U.S. Pat. No. 3,756,830, it can be dissolved in a halogenated alcohol, acetone, water, pyridine or the like, or a mixed solvent thereof, and added in the form of a solution.

(2) A solution prepared by dissolving a bluing dye in an oil, that is, a solvent substantially insoluble in water and having a boiling point of about 160 ° C. or higher can be added to a hydrophilic colloid solution and dispersed. As the high boiling point solvent, as described in U.S. Pat.No. 2,322,027, for example, phthalic acid alkyl ester (dibutyl phthalate, dioctyl phthalate, etc.),
Phosphate esters (diphenyl phosphate, triphenyl phosphate, tricresyl phosphate, dioctyl butyl phosphate), citrate esters (e.g., tributyl acetyl citrate), benzoate esters
(E.g., octyl benzoate), alkyl amides (e.g., diethyl lauryl amide), fatty acid esters (e.g., dibutoxyethyl succinate, diethyl azelate), trimesic esters (e.g., tributyl trimesate)
Etc. can be used. Further, organic solvents having a boiling point of about 30 ° C. to about 150 ° C., for example, ethyl acetate, lower alkyl acetates such as butyl acetate, ethyl propionate, secondary butyl alcohol, methyl isobutyl ketone, β-ethoxyethyl acetate, methyl cellosolve acetate, and the like. A solvent that is easily dissolved in water, for example, an alcohol such as methanol or ethanol can also be used. Here, the use ratio of the bluing dye to the high boiling point solvent is preferably 10 to 1/10 (mass ratio).

(3) A method of incorporating a bluing dye in a photographic emulsion layer or other hydrophilic colloid layer as a filled polymer latex composition can also be applied. As such a polymer latex, for example, a polyurethane polymer,
For example, a polymer polymerized from a vinyl monomer can be used. Suitable vinyl monomers include acrylates (methyl acrylate, ethyl acrylate,
Butyl acrylate, hexyl acrylate, octyl acrylate, dodecyl acrylate, glycidyl acrylate, etc.), α-substituted acrylate (methyl methacrylate, butyl methacrylate, octyl methacrylate, glycidyl methacrylate, etc.), acrylamide (butyl acrylamide, hexyl acrylamide, etc.), α- Substituted acrylamide (butyl methacrylamide, dibutyl methacrylamide, etc.), vinyl ester (vinyl acetate, vinyl butyrate, etc.), vinyl halide (vinyl chloride, etc.), vinylidene halide (vinylidene chloride, etc.), vinyl ether (vinyl methyl ether, vinyl octyl) Ether, etc.), styrene, side-chain substituted styrene (α-methylstyrene, etc.), core-substituted styrene (hydroxystyrene, chlorostyrene, methylstyrene, etc.), ethylene Examples include len, propylene, butylene, butadiene, and acrylonitrile. These may be used alone or in combination of two or more kinds, or other vinyl monomers may be mixed as a minor component. Examples of other vinyl monomers include itaconic acid, acrylic acid, methacrylic acid, hydroxyalkyl acrylate, hydroxyalkyl methacrylate, sulfoalkyl acrylate, sulfoalkyl methacrylate, and styrene sulfonic acid. These filled polymer latex, JP-B-51-39853, JP-A-51-59943, JP-A-53-137131, JP-A-54-32552
No., JP-A-54-107941, JP-A-55-133465, JP-A-56
-19043, JP-A-56-19047, JP-A-56-126830, and JP-A-58-149038. Here, as the usage ratio of the dye and the polymer latex,
10 to 1/10 (weight ratio) is preferred. In addition, latex is
Usually, an emulsion in which a macromolecule (polymer) is colloidally dispersed in water by the action of an emulsifier is used. Here, the polymer latex refers to a polymer in the latex.

(4) A method in which a hydrophilic polymer having a charge opposite to that of the dye ion is made to coexist as a mordant in the layer, and the dye is localized in a specific layer by an interaction between the dye and the dye molecule can also be applied. The polymer mordant is a polymer containing secondary and tertiary amino groups, a polymer containing a nitrogen-containing heterocyclic moiety, a polymer containing these quaternary cationic groups, etc., having a molecular weight of 5,000 or more, particularly preferably 10,000 or more Things. For example, vinyl pyridine polymer and vinyl pyridinium cation polymer described in U.S. Pat.No. 2,548,564, etc .; vinyl imidazolium cation polymer disclosed in U.S. Pat.No. 4,124,386, etc .; disclosed in U.S. Pat. Polymer mordant crosslinkable with gelatin etc .; US patent
3,958,995 specification, aqueous sol-type mordant disclosed in JP-A-54-115228 and the like; U.S. Patent 4,168,976; water-insoluble mordant disclosed in U.S. Pat.
Mordant capable of covalently bonding to a dye disclosed in JP-A-6-85, etc .; a polymer derived from an ethylenically unsaturated compound having a dialkylaminoalkyl ester residue described in British Patent No. 685,475; United Kingdom Patent 85
Products obtained by reacting polyvinylalkyl ketones with aminoguanidines as described in U.S. Pat.No. 0,281; polymers derived from 2-methyl-1-vinylimidazole as described in U.S. Pat. Can be mentioned.

(5) A method of dissolving a bluing dye using a surfactant is also applicable. Useful surfactants include:
It may be an oligomer or a polymer. For details of this polymer, see JP-A-53-138726, JP-A-60-2002
No. 51, JP-A-60-203935 and Japanese Patent Application No. 59-12766.

(6) In the above, a hydrophilic polymer can be used instead of the high boiling point solvent or in combination with the high boiling point solvent. Regarding this method, for example, German Patent 1,957,46
It is described in No. 7.

(7) A microcapsule method using a polymer having a carboxyl group, a sulfonic acid group or the like at the terminal as described in JP-A-59-113434 can also be applied. Further, for example, a hydrosol of a lipophilic polymer described in JP-B-51-39835 may be added to the hydrophilic colloid dispersion medium obtained above. As the hydrophilic colloid, gelatin is typical, but any other conventionally known colloids usable for photography can be used.

[0044] Blue The amount of seasoning dye, indicating a coating amount per photographic material simplex 1 m ^2, preferably from ^{1.5mg / m 2 ~5.0mg / m 2} , 2.0mg / m 2 ~4.5mg / m 2 Is more preferred.

In the light-sensitive material of the present invention, the inclusion of a dye capable of decoloring in the course of the development processing in the form of solid fine particles in any one of the layers can cut off so-called crossover light and improve sharpness. It is preferred in that respect. here,
Dyes that can be decolorized in the development process show sufficient light absorption before processing, but the absorbance in the visible part changes to 0.4 or less during the processing of development, fixing, and washing (including stabilization). And preferably changes to a range of 0 to 0.25, and reference can be made to JP-A-1-172828 or the like.

Hereinafter, dyes that can be decolorized during the development process will be described in detail. As the dye, known dyes or pigments, for example, "Handbook of Dyes" (pages 315 to 1109,
Organic Synthetic Chemistry Association, edited by 1970) and "Color Material Engineering Handbook" (pages 225 to 417, edited by Color Material Association, 1989) may be used.
A dye represented by the following formula (FA) is preferably used. Formula (FA): D- (X ₁ ) y ₁

In the formula (FA), D represents a group derived from a compound having a chromophore, and X ₁ has a dissociable proton or a dissociable proton bonded to D directly or via a divalent linking group. X ₁ represents a group represented by a linking group
Includes a linking group. y ₁ represents an integer of ₁ to 7.

Examples of the solid disperse dye used in the present invention include JP-A-11-344600 and JP-A-4-45.
436, JP-A-7-152112, JP-A-3-138640, International Patent WO88 / 0479.
4, European Patent (EP) 0274723 A1
JP, 276566, JP 299435, JP-A 52-92716, and 55-1553.
No. 50, 55-155351, 61-2
JP-A-59934, JP-A-48-68623, U.S. Pat. Nos. 2,275,583, 3,468,897, 3,746,539, 3,933,798, 4,130,429 and 4,408,41. JP-A-2-282244, JP-A-3-793.
No. 1, JP-A-3-167546, JP-A-1-26
No. 6536, No. 3-136038, No. 3-2
Nos. 26736, 3-138640 and 3-
No. 211542, Japanese Patent Application No. 6-227982, No. 6
-227983, 6-279297, 7-54
Nos. 026, 7-101968 and 7-135118
JP-A-2-282244, JP-A-7-113
No. 072, JP-A-7-53946 and the like.

In the present invention, as a method of solidifying fine particles of a dye which can be decolorized in the course of development processing, known fine-graining means (for example, ball mill, vibrating ball mill, planetary ball mill, sand mill, colloid Mill, jet mill, roller mill) and a method of mechanically dispersing can be used.

As the dispersing aid, the above-mentioned polymer compounds are used, and if necessary, two or more kinds may be used in combination.
At the same time, a known anionic, nonionic or cationic surfactant or a polymer may be used in combination, but it is preferable to use only the above-mentioned polymer compound. The dispersing aid is generally mixed with the dye powder or wet cake before dispersion and sent to a dispersing machine as a slurry.However, in a state where the dispersion aid is mixed with the dye in advance, heat treatment or treatment with a solvent is performed. It may be a dye powder or a wet cake. During the dispersion, as the fine particles are formed, they can be added to the dispersion. Further, it can be added to the dispersion for stabilizing the physical properties after dispersion. In any case, a solvent (eg, water, alcohol, and the like) is generally used. Before, during or after dispersion, the pH may be controlled with a suitable pH adjuster.

In addition to mechanical dispersing, fine particles may be formed by dissolving in a solvent by controlling the pH and then changing the pH in the presence of a dispersing aid. At this time,
An organic solvent may be used as a solvent used for dissolution, and the organic solvent is usually removed after the completion of fine particle formation.

The prepared dispersion is stored with stirring or stored in a highly viscous state (for example, in a jelly state using gelatin) with a hydrophilic colloid in order to suppress sedimentation of fine particles during storage. You can also do.
It is preferable to add a preservative for the purpose of preventing propagation of various bacteria during storage.

The solid fine particles of the dye thus prepared have an average particle diameter of usually 0.0005 to 10 μm, preferably 0.001 to 3 μm, particularly 0.01 to 0.1 μm.
Preferably it is 5 μm.

Such a dye may be added to any part of the light-sensitive material, but at least one of the undercoat hydrophilic colloid layer and / or the non-photosensitive hydrophilic layer provided between the support and the emulsion layer. It is preferable to add it to the hydrophilic colloid layer.
Here, the undercoating hydrophilic colloid layer refers to a hydrophilic colloid layer provided on a support, and the undercoating hydrophilic colloid layer is applied and dried, and then the upper layer is applied. Further, the non-photosensitive hydrophilic colloid layer provided on the undercoating hydrophilic colloid layer is coated simultaneously with the photosensitive silver halide emulsion layer as an upper layer, and the non-photosensitive hydrophilic colloid layer Before drying, a light-sensitive silver halide emulsion layer is applied. Alternatively, two or more photographic emulsion layers may be laminated, and the dye may be introduced into the lower (closer to the support) emulsion layer.

Undercoated hydrophilic colloid, solid fine-particle dye contained in a non-photosensitive hydrophilic colloid layer and / or a photographic emulsion layer provided between the silver halide emulsion layer and the undercoated hydrophilic colloid layer May be the same as each other or different from each other. Two or more dyes may be used in the same layer.

The amount of the decolorizable dye used as a solid content (per m ^{2 of} the support and the total of both surfaces of the support) depends on the required absorbance and the extinction coefficient of the dispersion.
g / m ² . Preferably in the range of 0.03~2g / m ^2, more preferably in the range of 0.04~0.15g / m ^2, particularly preferably in the range of 0.05~0.12g / m ² . At this time, the dye can be added to only one side.

The hydrophilic colloid is not particularly limited, but usually gelatin is preferably used. Side 1 m ² per gelatin coating amount of the support contained in the undercoat hydrophilic colloid layer containing a dye 0.05-0.3
It is preferably in the range of g. Especially 0.05-0.2g
Most preferably, it is within the range.

The coating amount of gelatin contained in the non-photosensitive hydrophilic colloid layer containing the dye is preferably in the range of 0.05 to 0.5 g per 1 m ² on one side of the support.
In particular, it is most preferably in the range of 0.1 to 0.4 g.

In the present invention, the surface protective layer provided on the photosensitive silver halide emulsion layer may be the same as a known one, and a hydrophilic colloid such as gelatin is used as a binder.

As the transparent support, various known ones may be used, and polyethylene terephthalate (PET) may be used.
And the like are preferably used.

There are no particular restrictions on the various additives used in the light-sensitive material of the present invention.
No. 9 can be used in the following sections.

Item The relevant place 1. Silver halide emulsion and method for producing the same From page 6, lower right column, line 6 to page 10, upper right column, line 12 of JP-A-2-68539. 2. Chemical sensitization method: From page 13, upper right column, line 13 to lower left column, line 16 of the same. 3. Antifoggants / stabilizers, page 10, lower left column, line 17 to page 11, upper left column, line 7 and page 3, lower left column, line 2, page 4 lower left column. 4. Spectral sensitizing dyes, page 4, lower right column, line 4 to page 8, lower right column. 5. Surfactants / Antistatic Agents, page 11, upper left column, line 14 to page 12, upper left column, line 9. 6. Matting agent / Slip agent / Plasticizer From page 12, upper left column, line 10 to upper right column, line 10 From page 10, line 10 in the lower left column to line 1 in the lower right column. 7. Hydrophilic colloid, page 12, line 11, upper right column to line 16, lower left column. 8. Hardening agent, page 12, lower left column, line 17 to page 13, upper right column, line 6. 9 Supports: From page 7, line 7 to line 20 in the upper right column. 10. Dyes and mordants From page 13, lower left column, line 1 to page 14, lower left column, line 9.

The method for processing the light-sensitive material of the present invention is not particularly limited. For example, JP-A-2-103737, page 16, upper right column, line 7 to page 19, lower left column, line 15;
Reference can be made to the description from page 3, lower right column, line 5 to page 6, upper right column, line 10 of JP-A-2-115837.

In the present invention, as a developing agent for processing a photographic light-sensitive material, a polyhydroxybenzene compound represented by hydroquinone used in a processing system of a medical silver halide photographic light-sensitive material, ascorbic acid, Alternatively, erythorbic acid (a diastereomer of ascorbic acid) and alkali metal salts thereof such as lithium salt, sodium salt and potassium salt are preferably used.

In order to process a photographic light-sensitive material, Dry till the material is carried into a developing tank until the drying step is completed.
The processing time of o Dry is preferably 20 to 100 seconds, particularly preferably 25 to 50 seconds. Further, in processing the photographic light-sensitive material of the present invention, the replenishment amount of each of the development and fixing is preferably 25 to 200 ml per 1 m ² of the photographic light-sensitive material.
0-160 ml is more preferred, and 60-130 ml is most preferred.

The silver halide photographic light-sensitive material used in the present invention is coated, dried, and wound into a roll under the following environmental conditions.
The absolute humidity is 1.4% by mass or less, preferably 1.3 to 0.1%.
Preferably, it is wound at 6% by mass. In the present invention, the product processing of the silver halide photographic light-sensitive material wound up in a roll shape after coating and drying is performed in an environment having an absolute humidity of 1.4% by mass or less, preferably 1.3 to 0.6% by mass. It is preferable to be processed. Here, the absolute humidity (% by mass) indicates the state of humid air, and the amount of water vapor (k
g) and the mass (kg) of dry air in humid air expressed as a percentage.

The silver halide photographic light-sensitive material is placed in a moisture-proof package, and its opening is adjusted so that the absolute humidity in the package is 1.4% by mass or less, preferably 1.1 to 0.6% by mass. Is sealed by a method such as heat sealing, and the photosensitive material is preferably equilibrated at the above absolute humidity. Further, it is particularly preferable that after the processing is completed, seasoning is performed in an environment having an absolute humidity of 1.4% by mass or less, and then the package is heat-sealed and sealed in the same environment.

The radiographic image forming method is as follows: 1) A silver halide photographic light-sensitive material of the present invention is arranged and arranged between two radiographic intensifying screens each having at least one phosphor layer on a support. 2) imagewise exposing the assembly to radiation; 3) peeling off the exposed photographic material from the intensifying screen; and 4) exposing and peeling from the intensifying screen. Developing the photographic photosensitive material with a developer.

The radiation intensifying screens used in the present invention are HR-4, HR-8, H
R-12 and the like.

The phosphor used in the phosphor layer of the intensifying screen of the present invention is preferably a rare earth phosphor represented by the following basic composition formula (I). The basic composition formula (I)
A phosphor obtained by adding an additive of about several mol% to the rare earth phosphor represented by the following formula to improve its properties, and silica, alumina or the like for modifying the surface thereof is also used in the present invention. be able to.

Basic composition formula (I): Mw Ow X: M '[where M represents at least one rare earth element selected from the group consisting of Y, La, Gd and Lu; X represents S, Se and At least one chalcogen selected from the group consisting of Te or F, Br, Cl, and I
Represents at least one halogen selected from the group consisting of: M ′ represents a rare earth element activating M; and w is w = 2 when X is a chalcogen and w = 2 when X is a halogen. It is one. ]

M ′ is preferably Dy, Er, Eu, H
o, Nd, Pr, Sm, Ce, Tb, Tm, and / or Yb, and particularly preferably Tb. Also, M
The ratio of activation of M ′ is 0.0002 to
It is preferably in the range of 0.2 (per mole of La, Gd or Lu), more preferably 0.000
5 to 0.05, particularly preferably 0.001 to 0.
02.

Specific examples of the rare earth phosphor represented by the basic composition formula (I) include the following phosphors: terbium-activated rare earth oxysulfide phosphor [Y ₂
O ₂ S: Tb, Gd ₂ O ₂ S: Tb, La ₂ O ₂ S: T
b, (Y, Gd) ₂ O ₂ S: Tb, (Y, Gd) ₂ O ₂
S: Tb, Tm, etc.], terbium-activated rare earth oxyhalide phosphor [LaOBr: Tb, LaOBr: T]
b, Tm, LaOCl: Tb, LaOCl: Tb, T
m, GdOBr: Tb, GdOCl: Tb, etc.], thulium-activated rare earth oxyhalide phosphor [LaOB]
r: Tm, LaOCl: Tm, etc.].

Of these rare earth phosphors, the one used for the intensifying screen of the present invention is preferably a terbium activated gadolinium oxysulfide (oxysulfide) phosphor (Gd ₂ O ₂ S: Tb). is there. This phosphor Gd ₂
O ₂ S: Tb forms part of Gd (50 atomic% or less)
It may be replaced by Y, La and / or Lu. Furthermore, an additive such as Ho may be added at a ratio of 10 atomic% or less, or a compound such as silica or alumina for modifying the surface may be added. The Gd ₂ O ₂ S: Tb phosphor is disclosed in US Pat.
No. 5,704, JP-A-11-344600. Essentially as X-ray phosphors used in the intensifying screen for use in the present invention Gd ₂ O ₂ S: It is preferred those represented by Tb, Tb-activated amount is 0.001 to 0.02 mol per Gd1 mol Is preferred.

The phosphor layer is prepared by dispersing the phosphor particles in an organic solvent solution containing a binder resin to prepare a dispersion, and then applying the dispersion to a support (such as a light reflection layer on a support). When an undercoat layer is provided, it can be formed by directly applying on the undercoat layer) and then drying. Alternatively, after applying the dispersion onto a separately prepared temporary support and drying to form a phosphor sheet, the phosphor sheet is peeled off from the temporary support and attached to the support using an adhesive. Is also good.

The particle size of the phosphor particles is not particularly limited, but is usually in the range of about 1 to 15 μm, preferably in the range of about 2 to 10 μm. It is preferable that the volume filling ratio of the phosphor particles in the phosphor layer is high, and usually 60 to
It is in the range of 85%, preferably in the range of 65-80%, particularly preferably in the range of 65-75%. The ratio of the phosphor particles in the phosphor layer is usually 80% by mass or more, preferably 90% by mass or more, and particularly preferably 9% by mass or more.
5 mass% or more.

The phosphor layer may contain a fluorescent dye or pigment. The amount of the dye is usually in the range of 0.1 to 5000 mg, preferably 1 to 1000 mg per 1 kg of the phosphor. And particularly preferably 5 to 5
An amount in the range of 00 mg. The technique is described in JP-A-11-344600.

The binder resin used for forming the phosphor layer, the organic solvent, and various additives that can be optionally used are described in the above-mentioned various known documents.

The thickness of the phosphor layer can be arbitrarily set according to the target sensitivity, but is preferably in the range of 70 to 150 μm for the front screen and 80 to 400 μm for the back screen. Range. Note that the X-ray absorption of the phosphor layer is determined by the amount of the phosphor particles applied.

The intensifying screen of the present invention is disclosed in
As described in Example 2 of 1899, the number of phosphor layers may be one, but may be two or more. For example,
As the phosphor layer, a layer made of phosphor particles having a relatively narrow particle size distribution and different particle diameters may be laminated, and in this case, a layer closer to the support may have a smaller particle size. . Further, a phosphor layer may be formed by mixing phosphor particles having different particle diameters, or a phosphor layer may be formed.
As described in page 3, left column, line 3 to page 4, left column, line 39, the phosphor layer may have a structure in which the particle size distribution of the phosphor particles is inclined. .

In the present invention, as described in Example 1 of JP-B-55-33560, the phosphor layer of the intensifying screen is prepared by using phosphors of different sizes such that the average particle size becomes smaller toward the support. It is preferable to apply a plurality of layers.
In this case, about 2 to 4 layers are provided on the same surface side of the support, but usually, it is preferably 2 layers.

The particle size gradient of the phosphor at that time is not particularly limited. There is no particular limitation on the size distribution of the phosphor, and a variation coefficient of about 10% monodispersion to about 70% polydispersion is used. For example, in the case of a Gd ₂ O ₂ S: Tb phosphor, the coefficient of variation of the particle size distribution is usually in the range of 30 to 50%, and monodisperse phosphor particles having a coefficient of variation of 30% or less are also preferably used. Can be. Although the phosphor size is not particularly limited, in the case of a plurality of layers, the phosphor size of the layer closest to the support is about 1 μm to 5 μm in average particle size, and the phosphor size of the layer farthest from the support is average particle size. It is preferable to use one having a diameter of about 4 μm to 15 μm.

The support for the intensifying screen can be appropriately selected from various supports used for known radiographic intensifying screens according to the purpose. For example, a polymer film containing a white pigment such as titanium dioxide or a polymer film containing a black pigment such as carbon black is preferably used. An undercoat layer such as a light reflecting layer containing a light reflecting material may be provided on the surface of the support (the surface on the side on which the phosphor layer is provided). The light reflection layer is a layer made of a polymer binder containing a white pigment such as titanium dioxide. For example, as described in Examples 1 and 2 of JP-A No. 9-21899, the average particle size is 0.1.
Titanium dioxide in the range of 1-0.5 μm is 1
It is preferable to provide a light reflection layer containing 0 to 75% in a thickness range of 10 to 100 μm.

It is preferable to provide a surface protective layer on the surface of the phosphor layer. The resin material used to form the surface protective layer is not particularly limited, but polyethylene terephthalate, polyethylene naphthalate, polyamide, aramid, fluororesin, polyester, and the like can be preferably used.

The light scattering length of the surface protective layer measured at the main emission wavelength of the phosphor is preferably in the range of 5 to 80 μm, more preferably 10 to 70 μm, particularly preferably 10 to 70 μm. The range is 60 μm.
Here, the light scattering length represents an average distance that light travels straight before being scattered once, and the shorter the scattering length, the higher the light scattering property. Further, the light absorption length representing the average free distance until light is absorbed is arbitrary, but from the viewpoint of screen sensitivity, it is preferable that there is no absorption by the surface protective layer because the decrease in sensitivity is small.

The surface protective layer preferably has a structure in which light scattering particles are dispersed and contained in a resin material. The light refractive index of the light-scattering particles is usually 1.6 or more, preferably 1.9 or more. The average particle size of the light-scattering particles is usually in the range of 0.1 to 1.0 μm. Examples of such light-scattering particles include fine particles of magnesium oxide, zinc oxide, zinc sulfide, titanium dioxide, niobium oxide, barium sulfate, lead carbonate, silicon dioxide, polymethyl methacrylate, styrene, and melamine. it can. Among these, preferred light scattering particles having a particularly high refractive index are fine particles of zinc oxide, zinc sulfide, titanium dioxide, and lead carbonate, and particularly preferably titanium oxide (particularly anatase type). If necessary, the surface protective layer may be formed by applying the light scattering particles to a resin material (binder resin).
Is prepared by dispersing the dispersion in an organic solvent solution containing, and then directly applying the dispersion onto the phosphor layer (or via an optional auxiliary layer), followed by drying. it can. Alternatively, a separately formed protective layer sheet may be provided on the phosphor layer using an adhesive.

The thickness of the surface protective layer is usually 2 to 12 μm
And preferably in the range of 3.5 to 10 μm. The surface protective layer may contain a fluorescent dye or pigment by adding particles of the fluorescent dye or fluorescent pigment to this dispersion.

Further, with respect to a preferred method for producing a radiation intensifying screen and materials used therefor, for example, JP-A-9-21899, page 6, left column, line 47 to line 8
5th line on the left column of the page, 17th line on the right column of the second page to 33rd line on the left column of the 3rd page of JP-A-6-347598, and
There is a detailed description from the left column of the page, line 42 to the left column of the fourth page, line 22, which can be referred to.

The silver halide photographic light-sensitive material of the present invention can be used for nondestructive inspection. In the case of nondestructive inspection, exposure is performed with X-rays or gamma rays having an energy of 10 kV or more. Regarding the nondestructive inspection, the description in JP-A-5-88296, JP-A-5-975530, and JP-A-5-323497 can be referred to.

[0090]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited thereto.

Example 1 (Preparation Method of Upper Layer Emulsion) 8.2 g of gelatin (average molecular weight: 15,000) and potassium bromide in 1 liter of water were used.
g of an aqueous solution containing 2.48 g of silver nitrate and an aqueous solution containing 6.1 g of potassium bromide were added to the aqueous solution maintained at 55 ° C. in 37 seconds by a double jet method while stirring. Subsequently, after an aqueous solution containing 19.2 g of gelatin was added, the temperature was raised to 76 ° C. while an aqueous solution containing 11.9 g of silver nitrate was added over 21.5 minutes. Further, 9.6 ml of a 25% by mass aqueous ammonia solution was added, and 10 minutes later, an aqueous solution containing 8.9 g of acetic acid was added. Subsequently, an aqueous solution of 143 g of silver nitrate and an aqueous solution of potassium bromide were added over 35 minutes by a control double jet method while maintaining the potential at pAg 8.5. The flow rate at this time was accelerated so that the flow rate at the end of the addition was 14 times the flow rate at the start of the addition. After addition 2
72 ml of a potassium N (2 mol / l) thiocyanate solution was added. Thereafter, the temperature was lowered to 35 ° C. to remove soluble salts by a sedimentation method.
9 g, 2.4 mg of Proxel (manufactured by ICI) and a thickener were added, and the mixture was adjusted to pH 5.9 and pAg 8.2 with an aqueous solution of sodium hydroxide, potassium bromide and silver nitrate. 56 ℃
To 4.3 mg of sodium ethylthiosulfonate
Was added, and 0.1 mol% of AgI fine particles having a diameter of 0.06 μm based on the total silver amount was added. Thereafter, 19.9 mg of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene, 495 mg of sensitizing dye-1 and sensitizing dye-2
1.8 mg was added. Five minutes later, 1.0 g of calcium chloride was added, and five minutes later, 1.8 m of chloroauric acid was added.
g and a solution containing 64 mg of potassium thiocyanate are premixed and added, followed by the selenium compound-
1.9 mg and 0.9 mg of sodium thiosulfate were added simultaneously. Aged for 55 minutes, 55 mg of mercapto compound M
The mixture was added and the temperature was lowered to 40 ° C. Thus, the emulsion O-1
I got The resulting emulsion had a total of 9 areas of the projected area of all grains.
3% is composed of grains having an aspect ratio of 3 or more and 65% is composed of grains having an aspect ratio of 4 or more. The average projected area diameter of all grains having an aspect ratio of 3 or more is 1.2 μm, and the standard deviation is 2
5%, average thickness 0.18 μm, average aspect ratio 6.4
Met.

Emulsion O-2 was prepared in exactly the same manner except that no AgI fine particles were added.

[0093]

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(Preparation Method of Coating Solution for Upper Emulsion Layer) Each compound was added to the upper emulsion which had been subjected to chemical sensitization so that the coating amount was as follows. It noted in the material coating amount per one side 1m ^2.

Silver coated 0.28 g Gelatin 0.34 g Dextran (average molecular weight 39,000) 60 mg Sodium polystyrene sulfonate (average molecular weight 600,000) 8.8 mg Additive-1 28.7 mg Additive-2 0.25 mg additives -3 per 0.05mg coating liquid amount at this time the emulsion layer was simplex 1 m ² 9.
It was 57 ml.

[0096]

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(Preparation Method of Lower Layer Emulsion) Silver nitrate 4 was added to an aqueous solution of 6.6 g of gelatin (average molecular weight: 15,000) and 7.1 g of potassium bromide kept at 40.5 ° C. in 1 liter of water while stirring. 5.10 g aqueous solution and potassium bromide
An aqueous solution containing 0 g was added by the double jet method in 39 seconds. Subsequently, after adding an aqueous solution containing 19.1 g of gelatin, the temperature was raised to 67 ° C. while adding an aqueous solution containing 10.0 g of silver nitrate over 21.5 minutes. Further, 5.3 ml of a 25% by mass aqueous ammonia solution was added, and 10 minutes later, an aqueous solution containing 5.4 g of acetic acid was added. Subsequently, 443 ml of an aqueous solution of 156.1 g of silver nitrate and 114 of potassium bromide were added.
g of iridium bromide and 443 ml of an aqueous solution containing 8.5 g of pAg.
The silver nitrate aqueous solution was added over 35 minutes by the control double jet method until the entire amount was added. The flow rate at this time was accelerated so that the flow rate at the end of the addition was 14 times the flow rate at the start of the addition. The addition amount of iridium bromide was adjusted so that the concentration of iridium contained per mol of silver halide was 5 × 10 ⁻⁶ mol. Next, 2N (2mo
1 / l) 17.5 ml of potassium thiocyanate solution were added. Thereafter, the temperature was lowered to 35 ° C., and soluble salts were removed by a sedimentation method.
2.7 g, 0.179 g of proxel and a thickener were added, and the mixture was adjusted to pH 6.35 and pAg 8.0 with aqueous sodium hydroxide, potassium bromide and silver nitrate. The temperature was raised to 56 ° C., 24.0 ml of 1% by weight potassium iodide were added, and then 4-hydroxy-6-methyl-1,3,3a,
165 mg of 7-tetrazaindene were added, followed by 3.2 mg of sodium ethylthiosulfonate. Subsequently, 628 mg of sensitizing dye-1 and 2.0 mg of sensitizing dye-2 were added. Eight minutes later, a solution containing 5 mg of chloroauric acid and a solution containing 63 mg of potassium thiocyanate were added in advance, and then added. Subsequently, 2.5 mg of selenium compound-1 and 1.1 mg of sodium thiosulfate were simultaneously added. . After aging for 76 minutes, 42 mg of mercapto compound M was added, and the temperature was lowered to 40 ° C. Thus, an emulsion U-1 was prepared. In the obtained emulsion, 93% of the total projected area of all grains consisted of grains having an aspect ratio of 3 or more, 65% consisted of grains having an aspect ratio of 4 or more, and the average projected area diameter of all grains having an aspect ratio of 3 or more was 0. .86 μm, standard deviation 28%,
The average thickness was 0.15 μm, and the average aspect ratio was 5.7.

Emulsion U-2 was prepared in exactly the same manner except that iridium bromide was not added.

(Preparation Method of Lower Layer Emulsion Layer Coating Solution) Each compound was added to the lower layer emulsion which had been subjected to chemical sensitization so that the coating amount was as follows. It noted in the material coating amount per one side 1m ^2.

Silver coated 1.28 g Gelatin 1.09 g Dextran (average molecular weight 39,000) 263 mg Sodium polystyrene sulfonate (average molecular weight 600,000) 18.9 mg Additive-1 68.4 mg Additive-2 1.6 mg Additive-3 0.32 mg Additive-4 5.1 mg Dye-1 (bluish dye) 3.5 mg Dye-2 0.41 g 1,2-bis (vinylsulfonylacetamido) ethane 42.3 mg At this time, this emulsion layer Is 28. per 1 m ^{2 on} one side.
It was 94 ml.

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(Preparation of Surface Protective Layer Coating Solution) The surface protective layer coating solution (pH with NaOH) was adjusted so that each of the components had the following coating amount.
Adjusted to 6.6).

Gelatin 695 mg / m ² sodium polyacrylate (average molecular weight 400,000) 60 mg / m ² butyl acrylate / methacrylic acid (6/4 mass ratio) copolymer polymer 66.9 mg / m ² Coating aid-1 15.8 mg / m ² coating aids -2 29.5 mg / m ² coating aids -3 7.7 mg / m ² coating aid -4 1.4 mg / m ² coating aid -5 3.6 mg / m ² Additive-5 2.4 mg / m ² matting agent-1 (number average particle size 3.8 μm) 54.2 mg / m ² matting agent-2 (number average particle size 4.2 μm) 17.5 mg / m ² Proxel 1 0.1 mg / m ² p-benzoquinone 0.8 mg / m ²

[0104]

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[0105]

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(Support) Biaxially stretched thickness 175 μm
The surface of the blue dyed polyethylene terephthalate film was subjected to corona discharge treatment, and the following components were mixed and prepared so as to have the following coating amounts (per one surface), respectively, using a wire bar coater, and sequentially applying the coating solutions. An undercoat layer consisting of two layers was formed.

A) Undercoat lower layer Butadiene / styrene copolymer latex (butadiene / styrene mass ratio = 31/69) Solid content 0.305 g / m ² 2,4-dichloro-6-hydroxy-s-triazine sodium salt 7 0.9 mg / m ² b) Undercoating upper layer (dye layer) Gelatin 123 mg / m ² Polyethyl acrylate 35 mg / m ² C ₁₂ H ₂₅ O (CH ₂ CH ₂ O) ₁₀ H 6.1 mg / m ² Proxel 0.43 mg / m ² acetic acid 0.84 mg / m ² polymethyl methacrylate particles (average particle size 2.5 μm) 1.1 mg / m ² Dye-3 16.4 mg / m ²

[0108]

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The above Dye-3 was prepared as a dispersion in a microcrystalline state by the following preparation method and added to a gelatin solution.

<Method of Preparing Microcrystal Dispersion> 20 g of Dye-3
And 200 g of a 1% by weight aqueous solution of carboxymethyl cellulose
And 287 g of water were mixed, and the mixture was mixed with a zirconium oxide (ZrO ₂ ) bead having a diameter of 2 mm using an Eiger mill (manufactured by Eiger Japan Co., Ltd.) at 5000 rpm.
After a time treatment, a dye dispersion having an average particle size of 0.37 μm was obtained.

(Photosensitive Material) The upper layer and lower layer silver halide emulsion coating solution and the coating solution for forming the surface protective layer were simultaneously coated on each side of the above-mentioned support having a double-sided undercoat layer by a multilayer method.
A sample of a silver halide photographic light-sensitive material was prepared by coating in the order of a lower emulsion layer, an upper emulsion layer, and a surface protective layer.

(Method of Manufacturing Intensifying Screen A for Front Side) Terbium-activated gadolinium oxysulfide phosphor (Gd ₂
250 g of O ₂ S: Tb, volume-weighted average particle size: 2.5 μm, variation coefficient of phosphor size distribution determined by Coulter counter method: 45 g), 6 g of polyvinyl butyral resin,
A coating solution P in which 1 g of a polyurethane resin and 0.25 g of a plasticizer were dispersed in methyl ethyl ketone was prepared. In the same manner, coating solution Q was prepared using a phosphor having a volume-weighted average particle diameter of 7 μm and a coefficient of variation of the phosphor size distribution determined by the Coulter counter method of 35%.

Next, a phosphor coating solution P was applied to a white polyethylene terephthalate film (thickness: 188 μm) into which titanium dioxide and air bubbles had been kneaded, so that the phosphor coating weight was 2 μm.
So that the 0 mg / cm ^2, the phosphor coating liquid Q onto by applied and dried at the same time as the phosphor coating weight is 25 mg / cm ^2, the phosphor layers of different layer structures phosphor size A screen was prepared. The volume filling factor of the phosphor in the phosphor layer was 66%.

Then, a polyester-based adhesive was applied to one side of polyethylene terephthalate having a thickness of 6 μm to a thickness of 0.5 μm.
μm, and a surface protective layer was provided on the phosphor layer by a heat lamination method.

(Preparation method of back-side intensifying screen B) 250 g of terbium-activated gadolinium oxysulfide phosphor (volume-weighted average particle size: 3 μm, coefficient of variation of phosphor size distribution determined by Coulter counter method: 45%) A coating liquid R in which 6.5 g of a polyvinyl butyral resin, 1 g of a polyurethane-based resin, and 0.25 g of a plasticizer were dispersed in methyl ethyl ketone was prepared. In the same manner, coating solution S was prepared using a phosphor having a volume-weighted average particle diameter of 10 μm and a coefficient of variation of the phosphor size distribution determined by the Coulter counter method of 25%.

Next, a phosphor coating solution R was applied to a white polyethylene terephthalate film (thickness: 188 μm) into which titanium dioxide and air bubbles had been kneaded.
So that the 0 mg / cm ^2, the phosphor coating liquid S on by applied and dried at the same time as the phosphor coating weight is 120 mg / cm ^2, the phosphor layers of different layer structures phosphor size A screen was prepared. The volume filling factor of the phosphor in the phosphor layer was 68%.

Thereafter, a polyester-based adhesive having a thickness of 0.5 μm was applied to one surface of polyethylene terephthalate having a thickness of 6 μm.
μm, and a surface protective layer was provided on the phosphor layer by a heat lamination method.

[Developing process] Automatic developing machine: Dry to be performed by CEPROS-M2 manufactured by Fuji Photo Film Co., Ltd.
This was performed in Dry 45 seconds (SP mode).

<Developer> Potassium hydroxide 28.0 g Sodium sulfite 75.0 g Diethylenetriaminepentaacetic acid 2.0 g Sodium carbonate 30.0 g Hydroquinone 18.0 g Triethylene glycol 6.0 g Diethylamino-ethyl-5-mercaptotetrazole 0.1 g Potassium bromide 1.0 g 1-phenyl-3-virazolidone 3.5 g 5-nitroindazole 0.3 g acetic acid 40.0 g 3,3'-dithiobishydrocinnamic acid 0.2 g Make up to 1 liter with water (pH 10.30) Adjusted)

<Fixing Solution> Sodium thiosulfate 96.4 g Sodium metabisulfite 22.0 g Ethylenediaminetetraacetic acid disodium dihydrate 0.025 g Make up to 1 liter with water (adjust to pH 5.00 with NaOH).

<Washing water> Running water When starting the development processing, each tank of the automatic developing machine was filled with the following processing liquid. Developing tank: 14 liters of developing solution Fixing tank: 14 liters of fixing solution Processing speed: Dry to Dry 45 seconds Developing temperature: 35 ° C. Fixing temperature: 32 ° C. Washing temperature: Approx. 30 ° C. Drying temperature: 55 ° C. Replenishment Amount …… Developer 18ml / 4 slices (25.4cm × 30.5cm) 1 sheet …… Fixer 24ml / 4 slices 1

(Evaluation of photographic properties) X-rays generated by applying a voltage of 80 kV by a three-phase pulse generator with a silver halide photographic material sandwiched from both sides for the front side and the back side of the intensifying screen. Was used as a light source for 0.1 second exposure. After the exposure, the development processing described above was performed. Sensitivity is Fog +
The sensitivity was represented by the reciprocal of the exposure amount giving a density of 1.0. Concentration Fog +
The change in density with respect to the natural logarithm of the light amount of a straight line connecting points giving 0.25 and Fog + 2.0 is shown as a gradation (contrast).

[0123]

[Table 1]

Normally, when taking images of both the heart region and the lung region, it is often the case to use radiographs with an increased latitude. However, a decrease in average contrast is accompanied by a decrease in discrimination. As the gradation, 1.8 to 3.0 is desirable, and 2.0 to 2.5 is more desirable. In the present invention,
It was possible to obtain a high gradation of 2.2 while suppressing an increase in fog and a decrease in sensitivity.

Example 2 (Preparation method of intensifying screen using fluorescent dye) <Preparation of support having titanium dioxide-containing reflective layer> Average particle size
500 g of 0.28 μm rutile-type titanium dioxide powder and 100 g of an acrylic binder resin were added to methyl ethyl ketone, and mixed and dispersed. This dispersion was uniformly applied onto the surface of a 250 μm-thick polyethylene terephthalate film so that the thickness after drying became 40 μm, and dried to obtain a support having a titanium dioxide-containing reflective layer. At this time, the volume filling ratio of the titanium dioxide particles was 48%.

<Preparation of Phosphor Sheet> Terbium-activated gadolinium oxysulfide (Gd ₂ O ₂ S: T
b, 250 g of phosphor particles having a Tb activation amount of 0.3 mol%) and 8 g of a polyurethane-based binder resin (trade name: Pandex T5265, manufactured by Dainippon Ink and Chemicals, Inc.)
2 g of an epoxy-based binder resin (trade name: Epicoat 1001 manufactured by Yuka Shell Epoxy Co., Ltd.) and 1 coumarin-6 (manufactured by Aldrich, compound No. 44, 23-1) of a fluorescent dye
0 mg, and 0.5 g of isocyanate compound (manufactured by Nippon Polyurethane Industry Co., Ltd., trade name: Coronate HX)
Was added to methyl ketone and dispersed with a propeller mixer.
According to this method, the average particle size is 2.0 μm, 3.0 μm, 6.
Each dispersion liquid containing 2 μm and 7.0 μm terbium-activated gadolinium oxysulfide phosphor particles is applied to the surface of the temporary support and dried to form a phosphor layer, and the temporary support is peeled off from this.
A phosphor sheet containing phosphor particles of each average particle size was obtained.

<Addition of Front-Side Phosphor Layer> A calendar roll process is performed using each of the phosphor sheets described above.
A phosphor layer having a multilayer structure with different average particle diameters of the phosphor particles was formed on a support having a reflective layer containing titanium dioxide. Phosphor particles having an average particle size of 7.0 μm were used in the upper layer (layer thickness after calender roll treatment) and phosphor particles having an average particle size of 2.0 μm were used in the lower layer (layer thickness after calender roll treatment). . The volume filling ratio of the phosphor particles in the phosphor layer was 70%.

<Attachment of Back-Side Phosphor Layer> Each of the above-described phosphor sheets is subjected to a calendar roll treatment to form a multi-layered structure in which the average particle diameter of the phosphor particles is different on a support having a titanium dioxide-containing reflective layer. A phosphor layer was formed. Phosphor particles having an average particle diameter of 6.2 μm were used for the upper layer (layer thickness after calender roll treatment) and phosphor particles having an average particle diameter of 3.0 μm were used for the lower layer (layer thickness after calender roll treatment: 80 μm). . The volume filling ratio of the phosphor particles in the phosphor layer was 70%.

<Preparation of Film for Surface Protective Layer> Anatase-type titanium oxide (trade name: A220, manufactured by Ishihara Sangyo Co., Ltd.) in polyethylene terephthalate having a thickness of 6 μm was used for the surface protective layer of the intensifying screen. A mixture kneaded by weight% was prepared. The scattering length of this PET film by monochromatic light of 545 nm was 30 μm, and the haze was 50. A polyester-based adhesive was applied to one surface, and a surface protective layer was provided on the phosphor layer by a lamination method.

It was confirmed that the same effect as in Example 1 was obtained even when the intensifying screen using the above fluorescent dye was used.

Example 3 The photosensitive material sample No. 1 of Example 1 was developed under the following conditions. Processing time was 5 minutes for all steps. Screen: IX-G ^* X-ray light source voltage: 200 kV Automatic developing machine: FIP-4000 ^* Developing solution: Super dol I ^* 30 ° C Fixing solution: Super FI ^* 30 ° C. Rinse: Approx. ℃ ^* Fuji Photo Film Co., Ltd.

As a result, it was found that the industrial X-ray photosensitive material was low in fog and high in sensitivity, although the gradation was soft as an industrial X-ray image.

[0133]

According to the present invention, a high-sensitivity, low-fogging image having a contrast giving excellent discrimination can be obtained in a radiographic photograph in which the latitude is widened.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G03C 1/83 G03C 1/83 5/16 5/16

Claims (5)

[Claims] 1. A silver halide photographic material having at least two silver halide emulsion layers on both sides of a transparent support, wherein the silver halide emulsion layer on the support side contains an iridium compound. Wherein at least one silver halide emulsion layer farther from the support than the silver halide emulsion layer with respect to the support contains silver halide grains whose grain surfaces have been converted with AgI fine grains. A silver halide photographic light-sensitive material characterized by containing: 2. The method according to claim 1, wherein the silver halide emulsion layer on the support side is K
2. The silver halide photographic material according to claim 1, which is an emulsion containing silver halide grains whose surface has been converted by I. 3. At least one of the silver halide emulsion layers
The bluing dye layer, indicated by the coating amount of the one side 1 m ² per of the support, a silver halide photographic material as claimed in claim 1 or 2 containing 1.5 mg / m ² or more 5.0 mg / m ² or less . 4. The silver halide photographic light-sensitive material according to claim 1, further comprising an undercoat layer containing a solid-dispersed dye capable of being decolorized in the course of development processing on at least one surface of said support. 5. X-ray exposure using a silver halide photographic light-sensitive material according to claim 1, wherein a radiation intensifying screen is arranged so as to sandwich both sides of the silver halide photographic light-sensitive material. And forming the image,
The radiation intensifying screen has a plurality of phosphor layers formed from a coating solution containing a phosphor on a support, and a radiation intensifying screen having a protective layer thereon, wherein at least the phosphor layer An image forming method in which two layers each contain a phosphor having a different average particle diameter, and the phosphor of the phosphor layer on the support side has a smaller average particle diameter than that of the phosphor layer on the protective layer side.