JPH08234353A - Silver halide photographic sensitive material, and method for forming x-ray image - Google Patents

Abstract

PURPOSE: To simultaneously improve both generation of silver sludge and safe light property, and provide a photosensitive material having quick treatment aptitude by providing specified silver halide particles in an emulsion layer, and also containing a specified compound in the emulsion layer. CONSTITUTION: The silver halide particles in an emulsion layer consist of flat silver halide particles having a silver chloride content of 10 mole % or more and an average aspect ratio of 3 or more, and at least one kind of compounds represented by the formula I or II is also contained in this emulsion layer. In the formulae I and II, R1 , R4 each represent hydrogen atom, or an alkyl group having 1-3 carbon atoms. However, R1 and R2 never represent hydrogen atoms at the same time. R5 represents hydroxyl group or an amino group, and R6 and R7 each represent hydrogen atom or an alkyl group having 1-5 carbon atoms. However, R6 and R7 never represent hydrogen atoms at the same time. M1 represents hydrogen atom, an alkali metal atom, or ammonium group. (m) represents 0, 1, or 2.

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 light-sensitive material, and more particularly to a silver halide photographic light-sensitive material having improved generation of silver sludge and safelight property. Further, a silver halide photographic light-sensitive material having high sensitivity, high image quality, excellent pressure resistance, and ultra-rapid processing suitability and its X
The present invention relates to a line image forming method.

[0002]

2. Description of the Related Art In recent years, silver halide photographic light-sensitive materials have an increasing tendency toward rapid processing and accompanying low replenishment of processing solutions. Therefore, they have better developability and fixability than silver iodobromide emulsions. Fast-moving silver chloride and silver bromide emulsions have been attracting attention.

However, the silver halide photographic light-sensitive material containing a large amount of chlorinated ions has a problem that silver sludge is liable to be generated in the processing tank during the running process and is particularly remarkable in the rapid process.

Further, as a drawback of the silver halide photographic light-sensitive material containing a large amount of chlorinated ions, it is poor in safety against safe light used in a dark room, and particularly in the case of a highly sensitive silver halide photographic light-sensitive material. However, it has a drawback that fog is likely to occur in a short handling time.

Since the adhesion of silver sludge to the film surface causes serious damage to the image, many studies have been made in the past, for example, JP-A-58-203439 is disclosed. Regarding the safe light resistance, for example, JP-A-59-177535 and JP-A-6-317874.
No. etc. are disclosed.

However, it is difficult to improve both the silver sludge and the safelight property at the same time by any of the methods, and there is a technique of improving the silver sludge property and the safelight property while maintaining the high sensitivity and having a rapid processing suitability. Development was desired.

On the other hand, tabular silver halide grains have recently attracted attention in response to the demand for rapid processing. Since the particles have a large specific surface area, a large amount of the sensitizing dye can be adsorbed, and therefore the spectral sensitivity can be enhanced. Further, in the case of the X-ray photosensitive material, there is a feature that the crossover light is remarkably reduced and an image with a small light scattering and a high resolution is obtained.

Therefore, by using such tabular grains, a silver halide photographic light-sensitive material having high sensitivity and high image quality by rapid processing is expected. However, a major drawback of such tabular grains is that fog is likely to occur due to pressure. This is because blackening occurs due to bending when handling the photosensitive material, and streaky fogging occurs due to rubbing of the photosensitive material during conveyance in an automatic developing machine, etc. Becomes In particular, this tendency becomes prominent when the transport speed is increased in the rapid processing.

The pressure resistance can be improved by increasing the amount of binder to increase the film thickness. However, when the amount of the binder is increased, the sensitivity is lowered due to poor permeation of the treatment liquid, and the drying property is deteriorated due to the increase of the water content, so that the rapid treatment property cannot be obtained.

Further, a medical radiographic image is usually formed by combining a fluorescent intensifying screen and an X-ray photographic light-sensitive material, and in addition to the image quality of the light-sensitive material itself, the influence on the radiation image of the fluorescent intensifying screen. Is also very large.

The combination of the fluorescent intensifying screen and the silver halide photographic light-sensitive material to be used in X-ray photography is not particularly specified, but when high-sensitivity photography is required, for example, in the lumbar spine. In photographing, head angiography, magnifying, etc., it is usual to use a high-light emitting intensifying screen and a standard or high-sensitivity silver halide photographic light-sensitive material in combination. When image quality is particularly important, it is common to use a high-sensitivity intensifying screen in combination with a standard-sensitivity silver halide photographic light-sensitive material for simple chest radiography, gastric contrast radiography, bone photography, etc. Is. Therefore, the combination of the high-sensitizing intensifying screen and the photosensitive material lowers the sharpness of the image, while the combination of the low-sensitizing intensifying screen and the photosensitive material results in the low sensitivity.

A method for improving sharpness and graininess by increasing the packing density of the phosphor of the fluorescent intensifying screen is disclosed in, for example, JP-A-3-
No. 21898. By combining X-ray light-sensitive materials with silver halide emulsion layers with different photographic characteristics on the front and back and fluorescent intensifying screens with different front and back, crossover light is cut, sharpness is increased, and tolerance to exposure fluctuations is also increased. Japanese Patent Application Laid-Open No. 2-266344, which has improved the degree, is also disclosed.

This technique aims to obtain various image contrasts by changing the combination with a fluorescent intensifying screen, but in practice the graininess deteriorates, which is not desirable for diagnosis. Have.

Conventionally, image graininess, sharpness and contrast have been mentioned as factors that greatly affect the image quality of medical X-ray images. Of these, for the graininess, for example, a combination of a standard light-sensitive material SR-G and a standard fluorescent intensifying screen SRO-250 (both manufactured by Konica Corporation) is a normal chest imaging condition. In the region where the tube voltage of the X-ray generating tube is 110 KVp or more, 50% or more of the deterioration of graininess is based on the X-ray quantum mottle.
This greatly deteriorates the graininess and image quality of line photographs. In the case of a combination using an X-ray film with higher sensitivity, the quantum mottle increased further, and the image quality deteriorated.

In order to improve the image quality of X-ray photography, it is necessary to reduce the quantum mottle and maintain and improve the sharpness. This is because when the crossover light of the X-ray photosensitive material itself is cut to improve the sharpness, the image quality is not necessarily improved due to the deterioration of the graininess corresponding to the sharpness improvement. Therefore, as disclosed in JP-A-3-21898 as described above, a method of increasing sharpness and graininess by increasing the packing density of the phosphor of the radiation fluorescent intensifying screen has been carried out.

In the case of using a light-sensitive material in which the crossover light is largely cut in combination with a fluorescent intensifying screen having a phosphor filling rate of 66% or less, a phenomenon that the graininess of the improved sharpness is deteriorated occurs. . Therefore, the crossover light of the X-ray photosensitive material itself was designed to exceed 20% to balance the image quality of graininess and sharpness. However, the image quality of the obtained X-ray photographic image is not sufficient, and further improvement has been desired.

[0017]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a high-sensitivity silver halide photographic light-sensitive material which improves both the generation of silver sludge and the safelight property at the same time and has suitability for rapid processing. is there. Another object of the present invention is to provide a silver halide photographic light-sensitive material having high sensitivity, high image quality, excellent pressure resistance and drying property, and suitability for ultra-rapid processing, and X.
A line image forming method is provided.

[0018]

The objects of the present invention have been solved by the following.

(1) In a silver halide photographic light-sensitive material having at least one light-sensitive silver halide emulsion layer on a support, the silver halide grains in the emulsion layer have a silver chloride content of 10 mol% or more. A tabular silver halide grain having an average aspect ratio of 3 or more, and the silver halide emulsion layer contains at least one compound represented by the following general formula [1] or general formula [2]. A silver halide photographic light-sensitive material characterized by the above.

[0020]

Embedded image

(In the formula, R ₁ and R ₂ are hydrogen atoms and have 1 to 1 carbon atoms.
It represents up to 3 alkyl groups. However, R ₁ and R ₂ cannot be hydrogen atoms at the same time. R ₃ and R ₄ are hydrogen atoms and have 1 carbon atom
Up to 3 alkyl groups, R ₅ represents a hydroxyl group, an amino group or an alkyl group having 1 to 3 carbon atoms. R _6, R ₇ represents a hydrogen atom, an alkyl group having up to 5 carbon atoms, an acyl group or a -COOM ₂ group up to 18 carbon atoms. However, R ₆ and R ₇ cannot be hydrogen atoms at the same time. M ₁ represents a hydrogen atom, an alkali metal atom or an ammonium group. M ₂ represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkali metal atom, an aryl group, or an aralkyl group having 15 carbon atoms.
m represents 0, 1 or 2. (2) At least one on at least one side of the transparent support.
A silver halide photographic light-sensitive material having a light-sensitive silver halide emulsion layer as a layer, the silver halide grains in the emulsion layer have a silver chloride content of 50 mol% or more and an average aspect ratio of 3 or more. It is composed of silver grains and has a ratio of (average thickness of the tabular silver halide grains) / (thickness of the emulsion layer).
A silver halide photographic light-sensitive material characterized by being 0.07 or more and less than 0.5.

(3) Fluorescence having an absorption amount of 45% or more for X-rays having an X-ray energy of 80 kvp, a filling factor of the phosphor of 68% or more, and a thickness of the phosphor of 135 μm or more and 200 μm or less. Sandwiching a silver halide photographic light-sensitive material on an intensifying screen, X
The X-ray image forming method of the silver halide photographic light-sensitive material as described in the above item (2), wherein the imagewise exposure is performed by irradiating a ray.

(4) In the above X-ray image forming method,
The spectral sensitivity of the silver halide photographic light-sensitive material has the same wavelength as the main emission peak wavelength of the fluorescent intensifying screen, and the full width at half maximum is
Necessary for the density of the exposed surface to be a minimum density of ± 0.5 when exposed with monochromatic light of 15 ± 5 nm and developed with a developer having the following composition at a developer temperature of 35 ° C. and a development time of 25 seconds. The amount of exposure
The X-ray image forming method according to the above item (3), which has a sensitivity of 0.027 lux seconds to 0.040 lux seconds.

Developer composition: potassium hydroxide 21 g potassium sulfite 63 g boric acid 10 g hydroquinone 26 g triethylene glycol 16 g 5-methylbenzotriazole 0.06 g 1-phenyl-5-mercaptotetrazole 0.01 g glacial acetic acid 12 g 1-phenyl-3-pyrazolidone 1.2 g Glutaraldehyde 5g Potassium bromide 4g Add water to make 1 liter and adjust the pH to 10.0.

(5) X-ray image formation according to the above item (3) or (4), wherein the silver halide photographic light-sensitive material is processed with an automatic processor for a total processing time of 40 seconds or less. Method.

The present invention will be described in detail below.

In the above formula [1] or formula [2] used for the tabular silver halide grains in the present invention,
Examples of the alkyl group having 1 to 4 carbon atoms include methyl,
Examples thereof include an ethyl, propyl or butyl group. Examples of the acyl group having up to 18 carbon atoms include acetyl group and benzyl group, and examples of the aralkyl group having up to 15 carbon atoms include benzyl group and phenethyl group.
The alkali metal atom of M ₁ is, for example, sodium ion or potassium ion.

Various synthetic methods are known for the compound of the above general formula [1] or general formula [2]. For example, the Strecker amino acid synthetic method known as an amino acid synthetic method may be used. The acetylation of is carried out by alternately adding alkali and acetic anhydride in an aqueous solution. Hereinafter, specific examples of the compound represented by the general formula [1] or the general formula [2] of the present invention will be shown, but the present invention is not limited thereto.

[0029]

Embedded image

[0030]

[Chemical 4]

The above compounds of the present invention may be used alone or in combination. Further, one or more compounds of the general formula [1] or the general formula [2] may be used in combination. The amount of the compound of the general formula [1] or the general formula [2] used is 1 × 10 ⁻⁶ mol to 1 × per mol of silver halide.
10 ^-1 mol well, it is particularly preferred even at 1 × 10 ^-5 mol to 1 × 10 ^-2 mol.

The silver halide emulsion may be added at any time during the emulsion manufacturing process, but it is preferably added at any step after the chemical ripening of the silver halide emulsion and before coating. Upon addition, the compound is water or a hydrophilic solvent,
For example, it is preferably dissolved in methanol, ethanol or the like and added.

The silver halide emulsion of the present invention comprises silver halide grains having an aspect ratio of 3 or more. The aspect ratio referred to here is, in a twin grain having two or more parallel twin planes, when a grain is projected from a direction perpendicular to the twin plane, the projected image of the grain becomes a circular image of the same area. Converted diameter and distance between two grain surfaces parallel to the twin plane (grain thickness)
And the ratio (particle diameter / particle thickness).

The particle size can be obtained, for example, by magnifying the particles with an electron microscope at a magnification of 10,000 to 50,000 times and measuring the diameter of the particles on the print or the area at the time of projection.
(The number of particles measured shall be 1000 or more indiscriminately.)
Similarly, the particle thickness can be obtained by actually measuring an electron micrograph.

In the present invention, the silver halide grains having an aspect ratio of 3 or more account for at least 50% or more of the total projected area. In the present invention, the aspect ratio may be 3 or more and 20 or less, preferably 3 or more and 18 or less.

Further, the tabular silver halide grains according to the present invention contain silver chloride. The silver chloride content is in claim 1
It is 10 mol% or more, preferably 20 mol% or more, and particularly preferably 30 mol% or more. In claims 2 to 6, the silver chloride content is preferably 50 mol% or more, more preferably 90 mol% or more.

The tabular silver halide grains used in the present invention may be silver chloride, silver chlorobromide, silver iodochloride, silver iodochlorobromide and the like, and more preferably silver chlorobromide and silver iodochlorobromide. .

The silver halide photographic emulsion which can be used in the present invention can be produced by a known method. For example, any method such as an acidic method, a neutral method or an ammonia method may be used, but a double jet method (simultaneous mixing method) is preferably used as a method of reacting a soluble silver salt with a soluble halogen salt. As one type of the simultaneous mixing method, a method of keeping pAg constant in a liquid phase in which silver halide is produced, that is, a so-called controlled double jet method can be used. According to this method, a silver halide emulsion having a regular crystal form and a substantially uniform grain size can be obtained. In determining the addition rate, reference can be made to JP-A-54-48521 and JP-A-58-49938.

When the present invention is applied to a medical X-ray photographic light-sensitive material, for example, a fluorescent intensifying screen whose main component is a phosphor which emits near-ultraviolet light or visible light upon exposure to penetrating radiation is used. It is desirable to expose this to both sides of a light-sensitive material prepared by coating the emulsion of the present invention on both sides. Here, the penetrating radiation is a high-energy electromagnetic wave, and X
Ray and gamma ray.

Preferred phosphors used in the intensifying screen according to the present invention include those shown below.

Tungstate phosphor (CaWO ₄ , MgW
O ₄ , CaWO _4, Pb, etc.), terbium-activated rare earth oxysulfide-based phosphor (Y ₂ O ₂ S: Tb, Gd ₂ O ₂ S: Tb, La ₂ O ₂ S: Tb, (Y.Gd) ₂
O ₂ S: Tb, (Y.Gd) O ₂ S: Tb.Tm, etc.], terbium-activated rare earth phosphate-based phosphor (YPO ₄ : Tb, GdPO ₄ : Tb, LaPO ₄ : Tb
Etc.), terbium-activated rare earth oxyhalide-based phosphors (LaOBr: Tb, LaOBr: Tb.Tm, LaOCl: Tb, LaOCl: Tb.
Tm, LaOCl: Tb.Tm.LaOBr: Tb GdOBr: Tb GdOCl: Tb
Etc.), thulium activated rare earth oxyhalide phosphor (LaOBr: Tm, LaOCl: Tm, etc.), barium sulfate phosphor _{[BaSO 4: Pb, BaSO 4:} Eu 2+, (Ba.Sr) SO 4: Eu ²⁺ etc.],
Divalent eurobium-activated alkaline earth metal phosphate-based phosphor [(Ba ₂ PO ₄ ) ₂ : Eu ²⁺ , (Ba ₂ PO ₄ ) ₂ : Eu ^2+, etc.] Divalent eurobium-activated alkaline earth metal Fluorohalide-based phosphor [BaFCl: Eu ²⁺ , BaFBr: Eu ²⁺ , BaFCl: Eu ²⁺ .Tb, Ba
FBr: Eu ²⁺ .Tb, BaF ₂・ BaCl ・ KCl: Eu ²⁺ , (Ba ・ Mg) F ₂・ BaCl ・
KCl: Eu ^2+, etc.], iodide-based phosphors (CsI: Na, CsI: Tl,
NaI, KI: Tl, etc.), sulfide-based phosphor [ZnS: Ag (Zn.Cd) S:
Ag, (Zn.Cd) S: Cu, (Zn.Cd) S: Cu.Al, etc.], hafnium phosphate-based phosphors (HfP ₂ O ₇ : Cu, etc.), provided that the phosphor used in the present invention is The phosphor is not limited, and any phosphor that emits light in the visible or near-ultraviolet region upon irradiation with radiation can be used.

The fluorescent intensifying screen of the present invention is preferably filled with a phosphor in a gradient particle size structure. In particular, it is preferable to apply large-diameter phosphor particles to the surface protective layer side, and to apply small-diameter phosphor particles to the support side.
The size of 2.0 μm and the large particle size is preferably in the range of 10 to 30 μm.

In order to manufacture the above-mentioned fluorescent intensifying screen, a step of forming a phosphor sheet comprising a binder and a phosphor, the phosphor sheet is placed on a support, and the softening temperature or melting point of the binder is set. It is preferable to manufacture the phosphor sheet in a step of adhering the phosphor sheet to the support while being compressed at the above temperature.

For the phosphor sheet which becomes the phosphor layer of the phosphor intensifying screen, the coating solution in which the phosphor is uniformly dispersed in the binder solution is applied onto the temporary support for forming the phosphor sheet, It can be manufactured by drying and then peeling from the temporary support. That is, first, a binder and phosphor particles are added to an appropriate organic solvent and mixed by stirring to prepare a coating liquid in which the phosphor is uniformly dispersed in the binder.

The binder has a softening temperature or melting point of 30.
A thermoplastic elastomer of ℃ to 150 ℃ is used alone or in combination with other binders. Since the thermoplastic elastomer has elasticity at normal temperature and becomes fluid when heated, it is possible to prevent the phosphor from being damaged by the pressure during compression. Examples of thermoplastic elastomers are the group consisting of polystyrene, polyolefin, polyurethane, polyester, polyamide, polybutadiene, ethylene vinyl acetate, polyvinyl chloride, natural rubber, fluororubber, polyisoprene, chlorinated polyethylene, styrene-butadiene rubber and silicone rubber. At least one thermoplastic elastomer selected from the above is included. The mixing ratio of the thermoplastic resin in the binder may be 10% by weight or more and 100% by weight or less, but the binder should be composed of as many thermoplastic elastomers as possible, particularly 100% by weight of the thermoplastic elastomer. preferable.

Examples of the solvent for preparing the coating solution include lower alcohols such as methanol, ethanol, n-propanol and n-butanol, hydrocarbons containing chlorine atom such as methylene chloride and ethylene chloride, acetone, methyl ethyl ketone and methyl isobutyl ketone. Examples thereof include esters of lower fatty acids and lower alcohols such as ketones, methyl acetate, ethyl acetate and butyl acetate, dioxane, ethers such as ethylene glycol monoethyl ether and ethylene glycol monomethyl ether, and mixtures thereof.

The mixing ratio of the binder and the phosphor in the coating liquid varies depending on the characteristics of the intended radiation intensifying screen, the type of the phosphor, etc., but generally the mixing ratio of the binder and the phosphor is 1: 1 to. It is preferably selected from the range of 1: 100 (weight ratio), and particularly preferably selected from the range of 1: 8 to 1:40 (weight ratio).

In the coating liquid, in order to improve the dispersibility of the phosphor in the coating liquid or to improve the binding force between the binder and the phosphor in the phosphor layer after formation. Various additives such as plasticizers may be mixed.

Examples of dispersants include phthalic acid, stearic acid, caproic acid, lipophilic surfactants and the like.

Examples of plasticizers include triphenyl phosphate,
Phosphates such as tricresyl phosphate and diphenyl phosphate, diethyl phthalate, phthalates such as dimethoxyethyl phthalate, glycolates such as ethylphthalylethyl glycolate and butylphthalbutyl glycolate, triethylene glycol and adipic acid Examples thereof include polyesters, polyesters of polyethylene glycol such as diethylene glycol and succinic acid, and polyesters of aliphatic dibasic acid. The coating liquid containing the phosphor and the binder prepared as described above is uniformly applied to the surface of the temporary support for sheet formation to form a coating film of the coating liquid. As the coating means, for example, a doctor blade, a roll coater, a knife coater or the like can be used.

As the temporary support, for example, glass, wool,
Materials made of various materials such as cotton, paper and metal can be used, but those which can be processed into a flexible sheet or roll for handling as an information recording material are preferable. From this point, for example, cellulose acetate film, polyester film, polyethylene terephthalate film, polyamide film, polyimide film, triacetate film, plastic film such as polycarbonate film, aluminum foil, metal sheet such as aluminum alloy foil, general paper and, for example, for photography Base paper, coated paper, or base paper for printing such as art paper, baryta paper, resin-coated paper, Belgian patent 784,61
Particularly preferred are processed papers such as papers sized with polysaccharides as described in No. 5, pigment papers containing pigments such as titanium dioxide, papers sized with polyvinyl alcohol and the like.

A coating solution for forming a phosphor layer is applied onto a temporary support, dried, and then peeled from the temporary support to obtain a phosphor sheet which becomes a phosphor layer of a fluorescent intensifying screen. Therefore, it is preferable that the surface of the temporary support is coated with a release agent in advance so that the formed phosphor sheet can be easily separated from the temporary support.

The next step will be described. A sheet for setting the phosphor formed as described above is prepared. This support can be arbitrarily selected from the materials listed for the temporary support.

Known fluorescent intensifying screens may be provided with an undercoat layer for imparting adhesiveness by coating a polymer material such as gelatin on the surface of the support in order to strengthen the bond between the support and the phosphor layer.
In order to improve sensitivity and image quality (sharpness, graininess), a light reflecting layer made of a light reflecting substance such as titanium dioxide or a light absorbing layer made of a light absorbing substance such as carbon black may be provided.

The support used in the present invention can also be provided with these various layers, and the structure thereof can be arbitrarily selected according to the desired purpose and application of the fluorescent intensifying screen.

The phosphor sheet obtained by the above is placed on a support, and the phosphor sheet is adhered on the support while being compressed at the softening temperature or the melting point or higher of the binder.

In this way, by utilizing the method of crimping the phosphor sheet on the support without previously fixing it, the sheet can be spread thinly and not only the phosphor is prevented from being damaged but also the sheet is prevented from being damaged. It is possible to obtain a high phosphor filling rate even at the same pressure as compared with the case of fixing and pressurizing.

Examples of the compression device used for the compression treatment of the present invention include those generally known such as calender rolls and hot presses. For example, the compression treatment with a calender roll is performed by placing the phosphor sheet obtained by on a support and passing it at a constant speed between rollers heated to the softening temperature or the melting point or higher of the binder. However, the compression device used in the present invention is not limited to these, and any device can be used as long as it can compress the sheet while heating it. The pressure during compression is 50
It is preferably at least kg / cm ² .

Usually, the fluorescent intensifying screen is provided with a transparent protective film for physically and chemically protecting the phosphor layer on the surface of the phosphor layer on the side opposite to the side in contact with the support. It is preferable to install such a transparent protective film also in the fluorescent intensifying screen of the present invention. The thickness of the protective film is generally 0.1 to 20.
It is in the μm range.

The transparent protective layer is, for example, a cellulose derivative such as cellulose acetate or nitrocellulose, or a synthetic polymer material such as polymethyl methacrylate, polyethylene terephthalate, polyvinyl butyral, polyvinyl formal, polycarbonate, polyvinyl acetate, vinyl chloride / vinyl acetate copolymer. Can be formed by a method in which a solution prepared by dissolving is prepared in a suitable solvent is applied to the surface of the phosphor layer. Alternatively, a plastic sheet made of polyethylene terephthalate, polyethylene naphthalate, polyethylene, polyvinylidene chloride, polyamide, etc., and a protective film forming sheet such as a transparent glass plate are separately prepared and an appropriate adhesive is used on the surface of the phosphor layer. It can be formed by a method such as adhesion.

As the protective layer used in the fluorescent intensifying screen of the present invention, a film formed by a coating film containing a fluorine resin soluble in an organic solvent is particularly preferable. Fluorine-based resin is a polymer of olefin containing fluorine (fluoroolefin),
Alternatively, it refers to a copolymer containing an olefin containing fluorine as a copolymer component. The film formed of the coating film of the fluororesin may be crosslinked. Fluorine-based protective film has the advantage that stains such as plasticizers that come out of the film when it comes into contact with other materials or X-ray film do not easily soak into the protective film, so the stains can be easily removed by wiping. There is.

When an organic solvent-soluble fluorine resin is used as the protective film forming material, this resin was dissolved in an appropriate solvent to prepare the resin. That is, the protective film is formed by uniformly applying a protective film-forming material coating liquid containing an organic solvent-soluble fluorine-based resin on the surface of the phosphor layer using a doctor blade or the like, and drying the coating. The formation of this protective film may be performed simultaneously with the formation of the phosphor by simultaneous multilayer coating.

The fluorine-based resin is a polymer of a fluorine-containing olefin (fluoroolefin) or a copolymer containing a fluorine-containing olefin as a copolymer component, such as polytetrafluoroethylene, polychlorotrifluoroethylene and poly Mention may be made, for example, of ethylene fluoride, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer and fluoroolein-vinyl ether copolymer oven.

Fluorine-based resins are generally insoluble in organic solvents, but copolymers containing fluoroolefin as a copolymer component become soluble in organic solvents due to the constitutional units other than the fluoroolefin to be copolymerized. The protective layer can be easily formed by applying a solution prepared by dissolving in a suitable solvent onto the phosphor layer and drying. Examples of such copolymers include fluoroolefin-vinyl ether copolymers. Further, since polytetrafluoroethylene and its modified products are also soluble in a suitable fluorine-based organic solvent such as a perfluoro solvent, they are protected by coating as in the case of the copolymer containing the above fluoroolefin as a copolymer component. A film can be formed.

The protective film may contain a resin other than the fluorine-based resin, and may contain a crosslinking agent, a hardener, an anti-yellowing agent and the like. However, in order to sufficiently achieve the above-mentioned object, the content of the fluorine-based resin in the protective film is preferably 30% by weight or more, more preferably 50% by weight or more, and most preferably 70% by weight or more. .

As a resin other than the fluorine-based resin contained in the protective film. Examples thereof include polyurethane resin, polyacrylic resin, cellulose derivative, polymethylmethacrylate, polyester, and epoxy resin.

The protective film of the intensifying screen used in the present invention may be formed of a coating film containing either or both of a polysiloxane skeleton-containing oligomer and a perfluoroalkyl group-containing oligomer.

The polysiloxane skeleton-containing oligomer has, for example, a dimethylpolysiloxane skeleton,
It preferably has at least one functional group, for example, a hydroxyl group, and preferably has a molecular weight of 500 to 100,000. In particular, the molecular weight is preferably in the range of 1000 to 10000, and more preferably 3000 to 10000.
Range. Further, an oligomer containing a perfluoroalkyl group, for example, a tetrafluoroethylene group is
It is desirable that the molecule contains at least one functional group, for example, a hydroxyl group, and the molecular weight is preferably in the range of 500 to 100,000. In particular, the molecular weight is preferably in the range of 100 to 100,000, more preferably 100 to 100,000.

If an oligomer containing a functional group is used, a cross-linking reaction occurs between the oligomer and the protective layer film forming resin during the formation of the protective film, and the oligomer is incorporated into the molecular structure of the film forming resin. Since the oligomer is not removed from the protective film by operations such as repeated use of the radiation intensifying screen for a long period of time or cleaning of the surface of the protective film, the addition effect of the oligomer is effective for a long time, so that the functional group has a functional group. The use of oligomers is advantageous. The oligomer is preferably contained in the protective film in an amount of 0.01 to 10% by weight, particularly preferably 0.1 to 2% by weight.

The protective layer may contain perfluoroolefin resin powder or silicone resin powder. As the perfluoroolefin resin powder or silicon resin powder, those having an average particle size of 0.1 to 10 μm are preferable, and particularly preferably 0.3 to 5 μm. These perfluoroolefin resin powders or silicone resin powders are contained in the protective film in an amount of 0.
It is preferably contained in an amount of 5 to 30% by weight, more preferably 2 to 20% by weight, and most preferably 5 to 15% by weight.

The protective film of the fluorescent intensifying screen is preferably a transparent synthetic resin layer having a thickness of 5 μm or less formed by coating on the phosphor layer. By using such a thin protective layer, the distance from the phosphor of the intensifying screen to the silver halide emulsion is shortened, which contributes to the improvement of the sharpness of the obtained X-ray image.

The filling rate of the phosphor as referred to in the present invention can be obtained from the following formula from the porosity of the phosphor layer formed on the support.

[0073]

[Equation 1]

Here, V: total volume of phosphor layer Vair: air volume in phosphor A: total weight of phosphor px: density of phosphor py: density of binder pair: density of air a: weight of phosphor b: Weight of binder Further, in the formula (1), since the pair is almost 0, the formula (1) can be approximately represented by the following formula (2).

[0075]

[Equation 2]

However, the definitions of V, Vair, px, py, a and b are the same as in the equation (1). In the present invention, the porosity of the phosphor layer is calculated by the equation (2). The filling rate of the phosphor can be calculated by the following equation (3).

[0077]

(Equation 3)

However, the definitions of V, px, py, a and b are the same as in the equation (1).

The present invention has an intrinsic filtration of 2.2 mm of aluminum.
The X-ray energy of a corresponding X-ray generator shows an absorption of 45% or more with respect to 80 kVp X-rays, the filling rate of the phosphor is 68% or more, and the thickness of the phosphor is 135 μm to 200 μm. It is preferable to perform imagewise exposure by irradiating a photosensitive paper with X-rays while sandwiching the silver halide photographic light-sensitive material of the present invention.
The X-ray absorption amount of the fluorescent intensifying screen can be measured by the following method.

X-rays generated from a tungsten target tube operated at 80 kVp with three-phase power supply were transmitted through an aluminum plate having a thickness of 3 mm, and fluorescence of a sample fixed 200 cm from the tungsten anode of the target tube. After reaching the intensifying screen, the X-ray dose transmitted through the intensifying screen is measured at a position 50 cm after the phosphor layer of the extra paper using an ionization type dosimeter to obtain the X-ray absorption amount. As the reference, the X-ray dose at the above measurement position measured without passing through the intensifying screen can be used. The fluorescent intensifying screen of the present invention can be produced according to the method disclosed in JP-A-6-75097. That is, it is preferable that the phosphor, the binder, the surface protective layer, the material for the conductive layer and the step of producing them in combination are produced according to the method disclosed in JP-A-6-75097. Further, it is preferable that the phosphor has large-sized particles arranged near the surface protective layer by a multilayer coating method.

The present invention shows an absorption amount of 45% or more with respect to X-rays having an X-ray energy of 80 KVp in an X-ray generator having an intrinsic filtration of 2.2 mm equivalent to aluminum, and a phosphor filling rate of 68%.
Imagewise exposure is preferably carried out by irradiating X-rays with the silver halide photographic light-sensitive material of the present invention sandwiched between fluorescent intensifying screens having a phosphor thickness of 135 μm to 200 μm. The X-ray absorption amount of the fluorescent intensifying screen can be measured by the following method.

X-rays generated from a tungsten target tube operated at 80 KVp with three-phase power supply were transmitted through an aluminum plate having a thickness of 3 mm, and fluorescence of a sample fixed 200 cm from the tungsten anode of the target tube. After reaching the intensifying screen, the X-ray dose transmitted through the intensifying screen is measured with a dosimeter at a position 50 cm after the phosphor layer of the intensifying screen,
Obtain the amount of X-ray absorption. As a reference, the X-ray dose measured at the above measurement position without passing through the intensifying screen can be used.

The production of the fluorescent intensifying screen of the present invention is described in JP-A-6-7509.
It can be created according to the method disclosed in No. 7. That is, it is preferable that the phosphor, the binder, the surface protective layer, the material for the conductive layer, and the step of producing them in combination are prepared according to the method disclosed in, for example, JP-A-6-75097. Furthermore, it is preferable that large particles are arranged near the surface protective layer of the phosphor by a multilayer coating method or the like.

[0084]

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

Example 1 (Preparation of Comparative Emulsion Em-1) 16 liters of gelatin was added to 1 liter of water.
g was dissolved and potassium bromide 0.4 was added to a container heated to 50 ° C.
g, 6 g of sodium chloride and 0.8 ml of a 10% ethanol solution of sodium polyisopropylene-polyoxyethylene-disuccinate were added, and then 1 g of an aqueous solution containing 200 g of silver nitrate, 84 g of potassium bromide and 28 g of sodium chloride were added. 1 liter of the aqueous solution was added by the double jet method over about 55 minutes. Gelatin after desalting
20 g was added and the mixture was stirred at 50 ° C. for 30 minutes for redispersion. When the obtained Em-1 was observed with an electron microscope, the average particle size was 0.40.
The particles were cubic grains of silver chlorobromide having a particle size of μm and a silver chloride content of 40 mol%.

(Preparation of Comparative Emulsion Em-2) Em-1 was prepared in the same manner as Em-1 except that 28 g of potassium bromide and 56 g of sodium chloride in the aqueous solution in the process of preparing Em-1 were used.
-2 was prepared. When the obtained Em-2 was observed with an electron microscope, it was silver chlorobromide cubic grains having an average grain size of 0.40 μm and a silver chloride content of 80 mol%.

(Preparation of Em-3) Gelatin 24 in 400 ml of water
g is dissolved, sodium chloride 11.2 M and potassium bromide 1.8
An aqueous solution containing M was used as a mother liquor and pAg was adjusted to 9.0.
To this mother liquor, sodium chloride 10.8M and potassium bromide 1.2M
And a 2 M silver nitrate aqueous solution were added by the double jet method at a constant flow rate (5 ml / min) for 30 minutes. During the addition, the temperature of the mother liquor was kept at 40 ° C, pH 7.0 and pAg 9.0. After desalting, 17 g of gelatin was added, and the mixture was stirred at 50 ° C. for 30 minutes for redispersion. When the obtained Em-3 was observed with an electron microscope, the average particle size was 0.40 μm and the average aspect ratio was
It was a silver chlorobromide tabular grain having a silver chloride content of 40 mol% of 4.0.

(Preparation of Em-4) In the same manner as in preparation of Em-3, the molar ratio of sodium chloride and potassium bromide in the mother liquor and the halide solution was set to 8: 2 and pAg was kept at 8.1. Em-4 was prepared. When the obtained Em-4 was observed with an electron microscope, the average particle size was 0.40 μm and the average aspect ratio was
It was a silver chlorobromide tabular grain having a silver chloride content of 4.0 mol% of 4.0.

(Preparation of Em-5) pA in the preparation of Em-3
Em-5 was prepared similarly except g was kept at 9.5.
When the obtained Em-5 was observed with an electron microscope, it was a silver chlorobromide tabular grain having an average particle size of 0.40 μm, an average aspect ratio of 10.0 and a silver chloride content of 40 mol%.

(Preparation of Em-6) In the preparation of Em-3, the molar ratio of sodium chloride and potassium bromide in the mother liquor and halide was 8: 2 and pAg was kept at 8.8. 6 was prepared.

When the obtained Em-6 was observed with an electron microscope, it was a silver chlorobromide tabular grain having an average particle size of 0.40 μm, an average aspect ratio of 10.0 and a silver chloride content of 80 mol%.

(Chemical sensitization of emulsion) Next, the above-mentioned emulsion Em-
After the temperature of 1 to 6 was adjusted to 60 ° C., the following spectral sensitizing dye was added as a solid fine particle dispersion to 0.7 mmol per mol of silver, and then a thiocyanic acid potassium salt, chloroauric acid and sodium thiosulfate mixed aqueous solution was added. And a dispersion of triphenylphosphine selenide were added, and the mixture was aged for a total of 2 hours. At the end of aging, a predetermined amount of 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene (TAI) was added as a stabilizer.

Sensitizing dye (A) 5,5'-dichloro-9-ethyl-3,
The anhydrous additive of 3'-di- (3-sulfopropyl) -oxacarbocyanine sodium salt and its addition amount (per mol of AgX) are shown below.

Potassium thiocyanate 95 mg Chloroauric acid 2.5 mg Sodium thiosulfate 2.0 mg Triphenylphosphine selenide 0.2 mg in terms of powder 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene (TAI) A solid dispersion of 280 mg sensitizing dye was prepared by a method similar to the method described in Japanese Patent Application No. 4-99437. That is, a predetermined amount of dye is added to water whose temperature has been adjusted to 27 ° C in advance, and a high-speed stirrer (dissolver) is added.
Obtained by stirring at 3,500 rpm for 30-120 minutes.

The above triphenylphosphine selenide was prepared as follows. That is, 120 g of triphenylphosphine selenide was added to 30 kg of ethyl acetate at 50 ° C. and completely dissolved by stirring. On the other hand 3.8k for photographic gelatin
g was dissolved in 38 kg of pure water, and 93 g of a 25 wt% aqueous solution of sodium dodecylbenzenesulfonate was added thereto. Next, these two liquids were mixed, and the peripheral speed of the dispersing blade was 40 at 50 ° C with a high-speed stirring type disperser having a dissolver with a diameter of 10 cm.
Dispersion was performed for 30 minutes at m / sec. Then, the ethyl acetate was rapidly removed under reduced pressure with stirring until the residual concentration of ethyl acetate became 0.3 wt% or less. Then, this dispersion was diluted with pure water to obtain 80 kg. A part of the thus obtained dispersion was collected and used in the above experiment.

Next, the following additives were added to the emulsion thus sensitized to prepare an emulsion layer coating solution. At the same time, a protective layer coating solution was also prepared.

(Preparation of coating liquid) The following additives were added to each of the obtained emulsions to prepare coating liquids. At the same time, a filter layer coating solution and a protective layer coating solution described below were also prepared. Using these coating solutions, the amount of silver coated on one side was 1.3 g / m ² and the amount with gelatin was 2.5 g / m ² with two slide hopper type coaters on the support at a speed of 120 m / min. Both sides were simultaneously coated on and dried in 2 minutes and 20 seconds to obtain a sample.

The support has a thickness of 175 μm and a concentration of 0.2.
Glycidyl methacrylate 50 wt%, methyl acrylate 10 wt%, butyl methacrylate 40 wt%
Polyethylene terephthalate base with a thickness of 175 μm coated with an aqueous dispersion obtained by diluting the copolymer latex consisting of the three monomers described above with pure water to a concentration of 10 wt% Was used.

(Preparation of Filter Layer Coating Solution) The coating amount was adjusted to the following per one surface.

The following filter dye solid dispersion 20 mg / m ² gelatin 0.2 g / m ²

[0101]

Embedded image

(Preparation of Emulsion Layer Coating Solution) The addition amount per mol of silver halide is shown. 1,1-Dimethylol-1-bromo-nitromethane 70 mg t-Butyl-catechol 400 mg 2,6-Bis (hydroxyamino) -4-diethylamino-1,3,5-triazine 0.15 mg Polyvinylpyrrolidone (molecular weight 10,000) 1.0 g Styrene -Maleic anhydride copolymer 2.5g Nitrophenyl-triphenylphosphonium chloride 50mg 1,3-Dihydroxybenzene-4-ammonium sulfonate 2g

[0103]

[Chemical 6]

Silver Sludge Inhibitor Amount Shown in Table 1 nC ₄ H ₉ OCH ₂ CH (OH) CH ₂ N (CH ₂ COOH) ₂ 1 g (Preparation of emulsion layer protective layer liquid) The amount added is per 1 g of gelatin. Show.

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

[0106]

[Chemical 7]

(Evaluation of Sample) (Evaluation of Sensitometry) The coated sample is treated at 23 ° C. and RH of 50%.
After leaving it under 1 day, fluorescent intensifying screen for X-ray SRO-250
It was sandwiched between (Konica Corp.), irradiated with X-rays through an aluminum wedge, and processed under the following processing conditions to evaluate the sensitivity. Sensitivity is the reciprocal of the amount of exposure energy required to give a density of fog +1.0, and is shown as relative sensitivity when the sensitivity of Sample No. 1 is 100.

The treating agent and the treating process are as follows.

(Developer composition) Part A (for 12 l finishing) Potassium hydroxide 450 g Potassium sulfite (50% solution) 2280 g Diethylenetriamine pentaacetic acid 120 g Sodium hydrogencarbonate 132 g Boric acid 40 g 5-Methylbenzotriazole 140 mg 1-phenyl-5 -Mercaptotetrazole 250mg 4-Hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone 120g Hydroquinone 400g Add water to make 6000ml.

Part B (for 12 l finishing) Glacial acetic acid 70 g 5-Nitroindazole 0.6 g Glutaraldehyde (50% solution) 8.0 g n-Acetyl-D, L-penicillamine 1.2 g Starter glacial acetic acid 120 g HO (CH ₂ ) ₂ S (CH ₂ ) ₂ S (CH ₂ ) ₂ OH 1g KBr 225g CH3N (C3H6NHCONHCH2SC2H5) 2 1g 5-methylbenzotriazole 1.5g Add water to make 1 liter. (Fixing liquid composition) Part A (18.3l for finishing) Ammonium thiosulfate (70wt / vol%) 4500g Anhydrous sodium sulfite 450g Sodium acetate ・ trihydrate 450g Boric acid
110 g tartaric acid
60 g Sodium citrate 10 g Gluconic acid 70 g 1- (N, N-Dimethylamino) -ethyl-5-mercaptotetrazole 18 g Glacial acetic acid 330 g Aluminum sulfate 62 g Add water to make 7200 ml.

To prepare a developing solution, add parts A and B to about 5 l of water at the same time, and add water while stirring and dissolving to make 12 l.
The H was adjusted to 10.53. This is used as a development replenisher.

20 ml of the above-mentioned starter was added to 1 liter of this replenishing solution to adjust the pH to 10.30 to prepare a working solution. For the fixer, add Part A to approximately 5 liters of water, add water while stirring and dissolve to make 18.3 liters, and use sulfuric acid and ammonia to adjust the pH to 4.
Adjust to 6 and use this as the fixer replenisher.

The development processing is SRX-503 (manufactured by Konica Corporation).
Was modified, and the line speed was set to 5000 mm / min, and all the dry to dry processing steps were performed in the 25-second mode in the following steps. The processing temperature is 35 ℃ for developing, 33 ℃ for fixing, and 20 for washing.
℃, drying was 50 ℃. The replenishment amount is 65 ml for each of the developing solution and the fixing solution per 1 m ² of the film.

(Evaluation of safe light toughness)
Place the sample at a temperature of RH 50% and pass through a red filter having the transmittance shown in Fig. 1, and use a white light bulb to raise the sample from 1.2 m above the sample to 30
After irradiating for a minute, the same development processing as in sensitometry was performed, and the increase value of fog was measured to evaluate the safelight property.

The smaller the value, the better the safelight property.

(Evaluation of silver sludge) 200 liters of quadrant sample exposed to light were immersed in 1 liter of a developing solution of the above composition which had been stirred at a pace of 10 seconds, and then left for 1 day. did.

At that time, the silver sludge on the wall and bottom of the beaker was visually evaluated according to the following four grades.

◯: Almost no silver sludge was observed, and there was no stain. Δ: Slight stain was observed on the bottom, but the developer was not cloudy. ×: Silver sludge was generated on the bottom and wall surfaces, and the developer was Slightly cloudy XX: Large amount of silver sludge was generated on the bottom and wall surfaces, and the developer was clearly cloudy. The above results are shown in Table 1 below.

[0119]

[Table 1]

As is clear from Table 1, according to the sample of the present invention, it is possible to obtain a high-sensitivity silver halide photographic light-sensitive material which does not generate silver sludge and is excellent in safelight resistance.

Example 2 (Preparation of silver iodide fine particles) <Solution A> 100 g ossein gelatin KI 8.5 g 2000 ml with distilled water <Solution B> 360 g AgNO3 360 g with distilled water <Solution C> 352 g Distilled water The solution A was added to a reaction vessel having a volume of 605 ml, and the solution B and the solution C were added at a constant rate over 30 minutes by the simultaneous mixing method while maintaining the temperature at 40 ° C. and stirring.

The pAg during the addition was kept at 13.5 by a conventional pAg control means. The produced silver iodide was a mixture of β-AgI and γ-AgI having an average particle size of 0.06 μm. This emulsion is called a silver iodide fine grain emulsion.

(Preparation of Solid Fine Particle Dispersion of Spectral Sensitizing Dye) The following spectral sensitizing dyes (A) and (B) were added at a ratio of 100: 1 to water preliminarily adjusted to 27 ° C., and a high speed stirrer was used. A solid fine particle dispersion of the spectral sensitizing dye was obtained by stirring with a (dissolver) at 3,500 rpm for 30 to 120 minutes. At this time, the concentration of the sensitizing dye (A) was adjusted to 2%.

Sensitizing dye (A): 5,5'-di-chloro-9-ethyl-3,3'-di- (3-sulfopropyl) oxacarbocyanine anhydride Sensitizing dye (B): 5, 5'-di- (butoxycarbonyl) -1,
1'-Diethyl-3,3'-di- (4-sulfobutyl) benzimidazolocarbocyanine-sodium salt anhydride (Preparation of hexagonal tabular seed emulsion) Hexagon with a silver iodide content of 2.0 mol% by the following method A tabular seed emulsion EM-A was prepared.

[0125] <solution A> ossein gelatin 60.2g Distilled water _{20.0l HO- (CH 2 CH 2 O} ) n - [CH (CH 3) CH 2 O] 17 - (CH 2 CH 2 O) m H (n + m = 5 to 7) 10% Methanol aqueous solution 5.6ml KBr 26.8g 10% H ₂ SO ₄ 144ml <Solution B> Silver nitrate 1487.5g Make distilled water 3500ml <Solution C> KBr 1029g KI 29.3g Distilled water 3500ml <Solution D> 1.75N KBr aqueous solution At a silver potential control amount of 35 ° C below, using a mixing stirrer disclosed in Japanese Patent Publication Nos. 58-58288 and 58-58289, Solution A and Solution B and Solution Nucleation was carried out by adding 64.1 ml of each of C by the double jet method over a period of 2 minutes.

After the addition of Solution B and Solution C was stopped, it took 60 minutes to raise the temperature of Solution A to 60 ° C.
B and solution C were mixed together at a flow rate of 68.5 ml / min and 5
Added for 0 minutes. During this period, the silver potential (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) was controlled to be +6 mV using the solution D. After the addition was completed, the pH was adjusted to 6 with 3% KOH, and immediately desalted and washed with water to obtain seed emulsion E.
It was M-A. In the seed emulsion EM-A thus prepared, 90% or more of the total projected area of silver halide grains consisted of hexagonal tabular grains having a maximum adjacent side ratio of 1.0 to 2.0. The hexagonal tabular average thickness was 0.07 μm, Electron microscope observation revealed that the diameter (circle diameter conversion) was 0.5 μm and the coefficient of variation was 25%.

(Preparation of silver iodobromide emulsion EM-1) The following 5
A tabular silver iodobromide emulsion EM-1 containing 1.3 mol% AgI was prepared using the various solutions.

[0128] <solution A> ossein gelatin _{29.4g HO- (CH 2 CH 2 O} ) n - [CH (CH 3) CH 2 O] 17 - (CH 2 CH 2 O) m H (n + m = 5 to 7) to 1760 ml with 10% methanol aqueous solution 1.25ml seed emulsion EM-a 2.65 molar equivalent of distilled water and 3000 ml <solution B> 3.5 N AgNO ₃ solution 1760 ml <solution C> KBr 730 g distilled water <solution D> iodo Equivalent to 0.06 mol of silver halide fine grain emulsion <Solution E> 1.75N KBr aqueous solution At a silver potential control amount of 60 ° C. below, using a mixing stirrer disclosed in Japanese Patent Publication Nos. 58-58288 and 58-58289, Solution A 658 ml of each of solution B and solution C and the total amount of solution D were mixed by the simultaneous mixing method (triple jet method), and it took 40 minutes for the flow rate at the end of addition to be twice the flow rate at the start of addition. One coating layer was added and grown.

After that, it took 70 minutes to grow the second coating layer by adding the remaining amount of the solution B and the solution C by the double jet method so that the flow rate at the end of the addition was 1.5 times that at the start of the addition. went.

During this period, the silver potential was controlled to be +40 mV using the solution D. After the completion of the addition, precipitation desalting was performed by the method described below to remove excess salts.

1) The reaction liquid after mixing was brought to 40 ° C., 20 g / mol AgX of the exemplified agglomerated gelatin agent G-3 was added, and 56 wt% acetic acid was added to reduce the pH to the value shown in Table 1, followed by decantation after standing. I do.

2) 11.8 l / mol AgX of pure water at 40 ° C was added, and the mixture was stirred for 10 minutes, then allowed to stand and decanted.

3) Repeat the above step 2 once more.

4) Gelatin 15 g / mol AgX, sodium carbonate and water are added to adjust the pH to 6.0 and dispersed to 450 ml / mol AgX. About 3,000 emulsions EM-1 thus obtained were observed and measured with an electron microscope to analyze the shape, which revealed tabular grains having an average equivalent circle diameter of 0.59 μm and an average thickness of 0.17 μm.
The coefficient of variation was 24%.

Preparation of EM-2-4 (silver iodobromide emulsion) Seed emulsion EM-A in solution A in the preparation method of EM-1.
And the silver ion potential during preparation were changed to prepare silver iodobromide emulsions EM-2 to 4 having different grain diameters and grain thicknesses. The grain shape of the obtained emulsion as observed by an electron microscope is shown in Table 2.

(Preparation of silver chloride emulsion) Preparation of EM-5 (pure AgCl tabular grains) <Solution A> High methionine gelatin (methionine 59.7 mM per 1 g of gelatin) 90 g CaCl ₂ .2H ₂ O 440 g Distilled water to 6000 ml <Solution B> 1017 g of silver nitrate 1800 ml with distilled water At 40 ° C, adjust the pH of solution A in the mixing stirrer shown in JP-B-58-58288 and 58-58289 to 5.1,
9 ml was added over 4 minutes. Then add another 55
Linear acceleration over minutes (9.32 times from start to finish)
During which time the entire amount of solution B was added. 4, 16 and 36 minutes after the start of addition of the solution B, 30 ml of a 37 mM adenine solution was added. After 10 minutes, 3.78 g of 3M CaCl ₂ solution was added. During the addition of the adenine and CaCl ₂ solution, the silver flow was stopped for 1 minute and the additives were mixed evenly.

During this period, the pH was controlled to be constant by adding NaOH or HNO ₃ . After completion of the addition, precipitation desalting was carried out in the same manner as in EM-1 to remove excess salts.

Approximately 3000 particles of EM-5 were observed and measured by an electron microscope, and the shape was analyzed. The average equivalent circle diameter was 2.
It was a tabular grain having a particle size of 10 μm and an average thickness of 0.23 μm.

Preparation of EM-6 to 8 (Pure AgCl tabular grains) In the preparation method of EM-5, the time of the addition of the first 29 ml of the solution B, the temperature of the solution A, and the silver ion potential during the addition of the solution B were determined. Pure AgCl with different particle diameter and particle thickness by changing
Tabular grains EM-6 to 8 were prepared. Table 2 shows the grain shape of the obtained emulsion as observed by an electron microscope.

Preparation of EM-9 (AgBr = 0.10, AgCl = 0.90 tabular grains) <Solution A> High methionine gelatin (methionine 59.7 mM per 1 g of gelatin) 103 g 4,5,6-triaminopyrimidine 343 g NaCl 246 g NaBr 48 g Distilled water to 6000 ml <Solution B> Silver nitrate 793 g Distilled water to 2000 ml At 40 ° C, adjust the pH of solution A in the mixing stirrer shown in JP-B-58-58288 and 58-58289 to 5.6. , 6 ml of solution B was added over 1 minute. Then add another 55
Accelerates linearly over minutes (9.8 times from start to end)
During which time the entire amount of solution B was added. Gelatin solution 411 ml was added 1, 5 and 18 minutes after the start of addition of the solution B. After 5 and 18 minutes, 1371 g of 4M NaCl solution and 20 mM of 4,
343 g of 5,6-triaminopyrimidine solution was added. During the addition of the above materials, the silver flow was stopped for 1 minute and the additives were mixed evenly.

During this period, the pH was controlled to be constant by adding NaOH or HNO ₃ . After the addition was completed, precipitation desalting was performed in the same manner as in EM-1 to remove excess salts.

Approximately 3000 particles of EM-9 were observed and measured with an electron microscope to analyze the shape.
The tabular grains were 1.80 μm and had an average thickness of 0.12 μm.

Preparation of EM-10 to 12 (AgBr = 0.10 AgCl = 0.90 tabular grains) In the preparation method of EM-9, the temperature, pH and solution B of solution A were measured.
Silver ion during addition, particle diameter by changing the potential,
Tabular grains E with different grain thickness AgBr = 0.10 AgCl = 0.90
M-10-12 were prepared. Table 1 shows the grain shape of the obtained emulsion as observed by an electron microscope.

Preparation of EM-13 (AgBr = 0.50 AgCl = 0.50 tabular grains) EM-13 was prepared in the same manner as EM-9 except that 192 g of NaBr was further added to the mixer. Approximately 3000 particles of EM-13 were observed and measured by an electron microscope, and the shape was analyzed. As a result, they were tabular particles having an average equivalent circle diameter of 1.80 µm and an average thickness of 0.12 µm.

Preparation of EM-14 to 16 (AgBr = 0.50 AgCl = 0.50 tabular grains) In the preparation method of EM-13, the temperature, pH and solution B of solution A were measured.
Silver ion during addition, particle diameter by changing the potential,
Tabular grains EM-14 to 16 having different grain thicknesses were prepared.
Table 2 shows the grain shape of the obtained emulsion as observed by an electron microscope.

Next, the obtained emulsion was subjected to spectral sensitization and chemical sensitization by the following methods.

After the emulsion was heated to 50 ° C., the sensitizing dye (A) was mixed with silver 1
After adding the above solid fine particle dispersion so as to be 460 mg per mol, 7.0 × 10 ⁻⁴ mol of ammonium thiocyanate salt was added per mol of silver, and chloroauric acid and hypo were added for optimum chemical ripening. And the above silver iodide fine grain emulsion to 3
After addition of × 10 ^-3 mol / mol Ag, 4-hydroxy-6-methyl-1,
Stabilization was carried out by adding 3,3a, 7-tetrazaindene (TAI) in an amount of 3 × 10 ^-2 mol.

(Preparation of Sample) Various additives described below were added to each emulsion to prepare emulsion coating solutions. The amount of addition is shown in an amount per mole of silver halide.

T-Butyl-catechol 400 mg Polyvinylpyrrolidone (molecular weight 10,000) 1.0 g Styrene-maleic anhydride copolymer 2.5 g Trimethylolpropane 10 g Diethylene glycol 5 g Nitrophenyl-triphenyl-phosphonium chloride 50 mg 1,3-Dihydroxybenzene-4 -Ammonium sulfonate 4 g 2-Mercaptobenzimidazole-5-sodium sulfonate 1.5 mg nC ₄ H ₉ OCH ₂ CH (OH) CH ₂ N (CH ₂ COOH) ₂ 1 g

[0150]

Embedded image

The additives used in the protective layer liquid are as follows. The added amount is shown as an amount per 1 g of gelatin.

Matting agent composed of polymethylmethacrylate having an area average particle size of 7 μm 7 mg Colloidal silica (average particle size 0.013 μm) 70 mg 2,4-dichloro-6-hydroxy-1,3,5-triazine sodium salt 30 mg Bis-vinyl Sulfonylmethyl-ether
36 mg

[0153]

[Chemical 9]

The above coating solution was uniformly applied to both surfaces of a blue-colored polyethylene terephthalate film base having a thickness of 175 μm and subjected to undercoating treatment, and dried to prepare Samples 1 to 1.
35 created. At this time, the amount of silver attached on one side of each sample is
It was adjusted to be 1.8 g / m ² . The film thickness of the emulsion layer was set as shown in Table 2 by adjusting the amount of gelatin. The dye (a) shown below was dispersed as a crossover cut material between the emulsion layer and the undercoat layer by the following method, and coating was performed so as to be inserted as a crossover cut layer.

[0155]

[Chemical 10]

Dispersion method Water and a surfactant alkanol XC (alkylnaphthalene-sulfonate: manufactured by DuPont) were put in a ball mill container, each dye to be added was added, and beads of zirconium oxide were put and the container was closed for 4 days. Ball mill disperse. Then, an aqueous gelatin solution was added and mixed for 10 minutes, and the beads were removed to obtain a coating solution.

The details of the obtained emulsion are shown in Table 2 below.

[0158]

[Table 2]

(Production of Fluorescent Intensifying Screen 1) Phosphor Gd ₂ O ₂ S: Tb (Average particle size 1.8 μm) 200 g Bound Polyurethane Thermoplastic Elastomer Demolac TPKL-5-2625 Solid Content 40% (Sumitomo Bayer Urethane Co., Ltd.) 20 g Nitrocellulose (digestibility 11.5%) 2 g Methyl ethyl ketone solvent was added to the above and dispersed with a propeller mixer to prepare a coating solution for forming a phosphor layer having a viscosity of 25 ps (25 ° C.). (Binder / phosphor ratio = 1/22) Separately, 90 g of a soft acrylic resin solid content and 50 g of nitrocellulose were dispersed and mixed by adding methyl ethyl ketone as a coating liquid for forming an undercoat layer, and a viscosity of 3 to 6 ps (25 (° C) dispersion was prepared.

A 250 μm-thick polyethylene terephthalate base (support) in which titanium dioxide was kneaded was placed horizontally on a glass plate, and the above coating solution for forming an undercoat layer was uniformly applied on the support using a doctor blade. From 25 ℃
The coating film was dried by gradually raising the temperature to 100 ° C. to form an undercoat layer on the support. The thickness of the coating film was 15 μm.

The above coating solution for forming a phosphor layer was uniformly applied and dried thereon with a film thickness of 240 μm using a doctor blade, and then compressed. The compression was performed using a calender roll at a pressure of 800 kgw / cm ² and a temperature of 80 ° C. After this compression, the thickness was 3 μm by the method described in Example 1 of JP-A-6-75097.
To form a transparent protective film.

As described above, the fluorescent intensifying screen 1 comprising the support, the undercoat layer, the phosphor layer and the transparent protective film was produced.

(Production of Fluorescent Intensifying Screen 2) Same as in the fluorescent intensifying screen 1 except that the phosphor layer forming coating liquid is applied at a thickness of 150 μm in the production of the fluorescent intensifying screen 1 and no compression is performed. Thus, a fluorescent intensifying screen 2 comprising a support, an undercoat layer, a phosphor layer and a transparent protective film was produced.

(Measurement of Characteristics of Fluorescent Intensifying Screen) 1) Measurement of Sensitivity MRE made by Eastman Kodak Co., Ltd. A single-sided silver halide photographic light-sensitive material was exposed to the front side of the fluorescent intensifying screen against an X-ray source. The material and then the fluorescent intensifying screen were placed in contact with each other, the X-ray exposure amount was changed by the distance method, and stepwise exposure was performed with a width of logE = 0.15. After exposure, the light-sensitive material was developed by the method described in the measurement of characteristics of silver halide photographic light-sensitive material described below to obtain a measurement sample.

The density of the measurement sample was measured with visible light to obtain a characteristic curve. The sensitivity was represented by the reciprocal of the X-ray exposure amount that gives Dmin + density 1.0, and was represented by the relative sensitivity with the fluorescent intensifying screen 1 being 100 (reference value). The results are shown in Table 3.

2) Measurement of X-ray Absorption Amount of X-ray generated from a tungsten target tube corresponding to 2.2 mm of aluminum with intrinsic filtration operated at 80 KVp by three-phase power supply is transmitted through an aluminum plate having a thickness of 3 mm. , Reach the sample fluorescent intensifying screen fixed 200 cm from the tungsten anode of the target tube, and then the X-ray dose transmitted through the intensifying screen is ionized at a position 50 cm behind the phosphor layer of the fluorescent intensifying screen. The dose was measured using a dosimeter and the amount of X-ray absorption was determined. As a reference, the X-ray dose at the measurement position measured without passing through the fluorescent intensifying screen was used. Table 3 shows the measured values of the X-ray absorption amount of each obtained fluorescent intensifying screen.
Shown in

[0167]

[Table 3]

As is apparent from the table, the fluorescent intensifying screen of the present invention has high sensitivity.

(Evaluation of Sensitivity of Photosensitive Material) Using a filter having the spectral characteristics shown in FIG. 1, a tungsten light source with a color temperature of 2856 ° K (light of 545 nm by the filter [the main emission wavelength of a fluorescent intensifying screen used together later) Was used as the irradiation light and SR-G (manufactured by Konica Corporation) was exposed as a comparative sample and its sensitivity was measured. That is, the illuminating light was applied to the photosensitive material for 1/25 seconds to perform exposure.

After the exposure, the photosensitive material of the sample is processed by an automatic processor FPM-
A 5000 (Fuji Photo Film Co., Ltd.) developing solution was developed at 35 ° C. for 25 seconds (total processing time 90 seconds). After peeling off the photosensitive layer on the surface opposite to the exposed surface, the density was measured to obtain a characteristic curve. From the characteristic curve, the lowest concentration +0.5
The amount of exposure required to obtain the density was calculated, and the sensitivity is shown in Table 3 as "lux seconds". In calculating the exposure amount, the illuminance of light emitted from a tungsten light source and transmitted through the above-mentioned filter was measured with an IM-3 type illuminance meter (manufactured by Topcon Corporation).

<Evaluation of Sensitometry> The obtained photosensitive material sample was sandwiched between fluorescent intensifying screens 1 and 2, and a penetrometer B was used.
After irradiating X-ray through the mold (made by Konica Medical), SR-DF processing liquid using the SRX-503 automatic developing machine (all are made by Konica Corporation)
At a developing temperature of 35 ° C. for a total processing time of 45 seconds. At this time, the replenishing amount of the processing solution was 210 ml / photosensitive material m ^{2 for} both the developing solution and the fixing solution.

The sensitivity was shown as a relative value with the reciprocal of the X-ray exposure amount required for obtaining the density of sample No. 1 being the minimum density + 1.0 as 100.

<Evaluation of ultra-rapid processability> After each sample was sandwiched between the fluorescent intensifying screens 1 and irradiated with X-rays in the same manner as in the evaluation of sensitometry.
The SRX-503 automatic processor was modified so that the processing time was as follows, and the processing was performed with the SR-DF processing solution at a developing temperature of 35 ° C. The replenishing amount of the processing solution was 125 ml / m ² for both the developing solution and the fixing solution.

Development time: 8 seconds Fixing time: 6.3 seconds Washing time: 3.4 seconds Between water washing-drying (squeeze): 2 seconds Drying time: 5.3 seconds Total processing time: 25 seconds I went as follows:
Using the above-mentioned automatic processor and processing agent, a large angle size (35.6 × 35.6) that was exposed so that the density after development processing would be about 1.0
cm) samples were continuously processed for 70 sheets. Subsequently, five samples for evaluation were similarly treated continuously, and the sample film immediately after the completion of drying was evaluated by touch. The drying air temperature was 50 ° C.

The evaluation criteria are as follows.

A: Completely dry (dry state) B: There is a slightly moist part (substantially usable level) C: Moist, films stick to each other D: Painted < Evaluation of pressure resistance: Each sample of 13 mm × 35 mm was kept at 23 ° C. and a constant temperature and humidity of 42% RH for about 1 hour, bent under a condition of a radius of curvature of 4 mm, and developed without being exposed. The difference between the density of the blackened portion and the density of the fog caused by the bending at this time was set as ΔD and used as a standard for the pressure fog. The smaller this value, the better the pressure fog resistance.

<Evaluation of sharpness and graininess> For each fluorescent intensifying screen / photosensitive material combination evaluated for sensitivity, a chest phantom made by Kyoto Kagaku Co., Ltd. was used as an X-ray source of 120 KVp (equipped with an aluminum equivalent filter of 3 mm thickness). A phantom was placed at a distance of 140 cm, an anti-scattering grid with a grid ratio of 8: 1 was placed behind it, and a photosensitive material and a fluorescent intensifying screen were placed behind it to perform photography.

In each of the photographs, the X-ray exposure amount was adjusted by changing the exposure time so that the densest part of the lung field was 1.8 ± 0.5. The obtained photograph was visually observed, and the graininess and sharpness were evaluated according to the following evaluation criteria.

Graininess Evaluation Criteria A: Almost no grain is conspicuous B: Slightly conspicuous C: Granules are conspicuous and some obstruction to interpretation D: Very conspicuous and obstruction to interpretation Sharpness evaluation criterion A: Very sharp B: Good There is slight blurring C: Conspicuous blurring causes some trouble in interpretation D: Interpretation is difficult due to blurring The above results are shown in Tables 4 and 5.

[0180]

[Table 4]

[0181]

[Table 5]

As is apparent from the table, the sample of the present invention had high sensitivity, excellent graininess and sharpness, and had a high quality image. Further, the sample according to the present invention was superior in pressure resistance and film drying property in rapid processing as compared with the comparative sample.

[0183]

According to the present invention, as demonstrated in the above-mentioned Examples, a high-sensitivity silver halide photographic light-sensitive material which suppresses the generation of silver sludge, at the same time improves the safelight resistance, and has suitability for rapid processing. Was obtained.

On the other hand, a silver halide photographic light-sensitive material and an X-ray image forming method having high sensitivity, high image quality, excellent pressure resistance and drying property and suitability for ultra-rapid processing were obtained.

[Brief description of drawings]

FIG. 1 is a transmittance curve of a red filter used in an example.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical display location G03C 5/26 G03C 5/26 5/30 5/30 G21K 4/00 G21K 4/00 A

Claims (5)

[Claims] 1. A silver halide photographic light-sensitive material having at least one light-sensitive silver halide emulsion layer on a support, wherein the silver halide grains in the emulsion layer have a silver chloride content of 10%.
At least 1% of the compounds represented by the following general formula [1] or general formula [2] in the silver halide emulsion layer, which comprises tabular silver halide grains having an average aspect ratio of 3 or more in mol% or more. A silver halide photographic light-sensitive material containing a seed. Embedded image (In the formula, R ₁ and R ₂ represent a hydrogen atom and an alkyl group having 1 to 3 carbon atoms. However, R ₁ and R ₂ cannot be hydrogen atoms at the same time. R ₃ and R ₄ are hydrogen atoms, Represents an alkyl group having 1 to 3 carbon atoms, R ₅ is a hydroxyl group, an amino group or 1 carbon atom
Represents an alkyl group up to 3; R _6, R ₇ represents a hydrogen atom, an alkyl group having up to 5 carbon atoms, an acyl group or a -COOM ₂ group up to 18 carbon atoms. However, R ₆ and R ₇ cannot be hydrogen atoms at the same time. M ₁ represents a hydrogen atom, an alkali metal atom or an ammonium group. M ₂ is a hydrogen atom, having 1 to 1 carbon atoms
Up to 4 alkyl groups, alkali metal atoms, aryl groups,
Represents an aralkyl group having up to 15 carbon atoms. m is 0, 1 or 2
Represents ) 2. A silver halide photographic light-sensitive material having at least one photosensitive silver halide emulsion layer on at least one side of a transparent support, wherein the silver halide grains in the emulsion layer have a silver chloride content of 50. Mol% or more and an average aspect ratio of 3 or more tabular silver halide grains, and the ratio of (average thickness of the tabular silver halide grains) / (thickness of the emulsion layer) is 0.07 or more and less than 0.5. A silver halide photographic light-sensitive material characterized by being present. 3. The X-ray energy is 4 for an X-ray having an energy of 80 kvp.
Irradiates with X-rays with a silver halide photographic light-sensitive material sandwiched between fluorescent intensifying screens with an absorption of 5% or more, a phosphor packing rate of 68% or more, and a phosphor thickness of 135 μm or more and 200 μm or less. The X-ray image forming method of the silver halide photographic light-sensitive material according to claim 2, wherein the imagewise exposure is carried out. 4. In the above X-ray image forming method, the spectral sensitivity of the silver halide photographic light-sensitive material has the same wavelength as the main emission peak wavelength of the fluorescent intensifying screen, and the full width at half maximum is 15 ±.
The amount of exposure required to reach a minimum density of ± 0.5 when exposed with 5 nm monochromatic light and developed with a developer having the following composition at a developer temperature of 35 ° C and a development time of 25 seconds. Is 0.027
The X-ray image forming method according to claim 3, wherein the X-ray image forming method has a sensitivity of lux seconds to 0.040 lux seconds. Developer composition Potassium hydroxide 21g Potassium sulfite 63g Boric acid 10g Hydroquinone 26g Triethylene glycol 16g 5-Methylbenzotriazole 0.06g 1-Phenyl-5-mercaptotetrazole 0.01g Glacial acetic acid 12g 1-Phenyl-3-pyrazolidone 1.2g Glutaraldehyde 5g Potassium bromide 4g After adding water to make 1 liter, the pH is adjusted to 10.0. 5. In the above X-ray image forming method, the total processing time of the silver halide photographic light-sensitive material is reduced by using an automatic processor.
The X-ray image forming method according to claim 3, wherein the processing is performed for 40 seconds or less.