JP2001209150A - Silver halide photographic sensitive material, processing method for same and image forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high contrast silver halide photographic sensitive material for X-ray mammography excellent in diagnostic ability and having good scuffing and wear resistances and good resistance to the leaving of a fingerprint, a processing method for the sensitive material and an image forming method. SOLUTION: In the silver halide photographic sensitive material with at least one photosensitive silver halide emulsion layer and an upper non- photosensitive colloidal layer on one face of the base and a backing layer on the other face, spherical polymer particles having <=10% relative standard deviation of particle diameter are contained in the non-photosensitive colloidal layer and >=50% of the total projected area of all silver halide grains in the at least one photosensitive silver halide emulsion layer is occupied by flat platy silver halide grains having an aspect ratio of 3-30 doped with ions of at least one metal selected from Rh, Ru, Re and Os.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a silver halide photographic material having a light-sensitive silver halide emulsion layer on one side of a support and a backing layer on the other side. In particular, a silver halide photographic light-sensitive material for single-sided exposure for medical use (hereinafter, also referred to as "photographic light-sensitive material" or simply as "light-sensitive material")
About.

[0002]

2. Description of the Related Art In recent years, it has been found from the survey of disease trends in Japan that the number of cases of breast cancer is increasing, and early detection of breast cancer in health examinations has become an important issue. Conventionally, breast cancer screening includes visual inspection, palpation, ultrasonic image diagnosis, X-ray mammography (mammography), and the like.
The importance of mammography is increasing due to its diagnostic effectiveness. In X-ray mammography, since the subject contrast is originally low, a source having a low tube voltage (40 kVp or less) having a high X-ray absorption is used. However, the image to be diagnosed is still often a tumor shadow or the like having only a slight contrast, and there is a difficulty in finding an early-stage cancer in particular. Further, microcalcified images having a size of several hundred μm are also important for the diagnosis of breast cancer, and it is necessary to accurately read their morphology. Since the calcified portion has a high X-ray absorption rate, it is represented as a low density point on the image.
Therefore, a film having a high gradation in a low density portion is suitable for detecting microcalcification.

As means for increasing the gradation of the film, a method using an emulsion having a high degree of monodispersity, a method using a high contrast agent, a method of forming a multilayer structure and disposing a low-sensitivity emulsion layer on an upper layer are known. However, excessively increasing the gradation of the film makes the graininess more conspicuous, so that the identification of the low-contrast image often deteriorates. Therefore, a means for adjusting to an appropriate gradation is desired.

[0004] As a means of enhancing contrast, rhodium (Rh), ruthenium (Ru), rhenium (R)
e), a method of doping a metal ion such as osmium (Os) or a metal complex ion is conventionally known. Most of these techniques are for obtaining ultra-high contrast characteristics as a photosensitive material for printing, and contain a large amount of rhodium salt. However, by reducing the amount of rhodium salt, a process suitable for mammography which is the object of the present invention is achieved. It is possible to adjust the tone.

For example, JP-A-6-102613 discloses that
A method is described in which a relatively small amount of a rhodium salt is added to silver iodobromide containing 4 mol or less of silver iodide together with a spectral sensitizing dye before chemical sensitization. However, photosensitive materials using silver halide particles doped with metal ions such as rhodium, ruthenium, rhenium and osmium or metal complex ions are liable to be scratched, and desensitization due to the attachment of fingerprints (so-called fingerprint marks). It was found that it was easy to occur.

In mammography, as described above, it is important for diagnosis to read low-density fine dot-like, streak-like, glass-like, etc. images as calcified images. The occurrence of fingerprints and fingerprints may lead to misdiagnosis.

On the other hand, tabular silver halide grains are known to easily obtain high sensitivity and have high covering power, and because of their excellent properties, have been used in a wide variety of photosensitive materials. However, it was found that when tabular silver halide grains were doped with a rhodium salt or the like in order to increase the gradation, scratch resistance and fingerprint trace resistance deteriorated more.

Japanese Patent Application Laid-Open No. 2-219051 describes a color photographic light-sensitive material containing tabular silver halide grains containing a noble metal such as rhodium, ruthenium, osmium and iridium. It is described that by acting as a desensitizer and mixing particles having the same particle size, a gradation can be formed in a wide exposure range, and processing fluctuation and gradation preservability are improved. Also, JP-A-9
No. 197597 describes that tabular silver halide grains are doped with at least one selected from chromium, ruthenium, rhodium, rhenium and osmium, and selenium-sensitized to increase the sensitivity and the fog during storage over time. Improved techniques are disclosed. However, none of these publications disclose the scratch resistance and fingerprint trace resistance required of the photosensitive material for mammography which is the object of the present invention.

[0009]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a silver halide photographic material for X-ray mammography having high contrast, excellent diagnostic performance, and excellent scratch and fingerprint resistance. An object of the present invention is to provide a processing method and an X-ray image forming method using the same.

[0010]

SUMMARY OF THE INVENTION The object of the present invention has been attained by the structure according to claims 1 to 18.

Hereinafter, the present invention will be described in detail. The silver halide grains used in the present invention have an aspect ratio of 3 to 30.
Are preferred. Tabular silver halide grains are crystallographically classified as twins. Twins are crystals having one or more twin planes in one grain. Classification of the twin morphology in silver halide grains is based on the report by Klein and Moiser in Photographhishhe.
Korespondenz ”, Vol. 99, pp. 99, pp. 100
The volume is described in detail on page 57.

The tabular silver halide grains used in the present invention have one or two or more twin planes parallel to each other in the grains, and these twin planes form the surface of the tabular grains. The plane exists substantially parallel to a plane having the largest area (also referred to as a main plane) among the planes. The most preferred form is when it has two parallel twin planes.

In the present invention, the aspect ratio refers to the ratio between the area-converted particle diameter and the particle thickness (ie, aspect ratio = equivalent circle diameter / thickness). Here, the area-converted particle size means the diameter of a circle having an area equal to the area when the particle is projected perpendicular to the main plane. On the other hand, the volume-converted grain size means the diameter of a sphere having the same volume as each silver halide grain. Grain thickness is the thickness of a grain in a direction perpendicular to the major plane and generally corresponds to the distance between the two major planes.

The average equivalent circle diameter of the tabular silver halide grains is preferably 0.1 to 10.0 μm, more preferably 0.2 to 10.0 μm.
5.0 μm is preferred, and 0.3 to 2.0 μm is particularly preferred. The average grain thickness is preferably 0.01 to 0.3 μm, more preferably 0.05 to 0.25 μm, and particularly preferably 0.07 to 0.2 μm.

The projected area and thickness of the particles for calculating the area-converted particle diameter and the volume-converted particle diameter can be obtained by the following methods.
That is, a sample was prepared by applying a latex ball having a known particle size as an internal standard on a support and silver halide particles such that the main plane was oriented parallel to the substrate, and shadowing was performed by carbon deposition from a certain angle. , A replica sample is prepared by a normal replica method. An electron micrograph of the replica sample is taken, and the projected area and thickness of each particle are determined using an image processing device or the like. In this case, the projected area of the particle can be calculated from the projected area of the internal standard, and the thickness of the particle can be calculated from the length of the internal standard and the shadow of the particle.

In the present invention, the average value of the aspect ratio, the area-converted particle size, the grain thickness, and the volume-converted particle size can be determined by arbitrarily determining the number of silver halide grains contained in the silver halide emulsion by using the above-mentioned replica method. The value measured as above and obtained as an arithmetic average thereof is referred to.

The coefficient of variation of the silver halide grain in terms of volume is a value defined by the following equation using the value obtained from the above measurement. The coefficient of variation of the silver halide grains according to the present invention in terms of volume is preferably 0.2 or less.
1 or less is more preferable. Coefficient of variation of volume-converted particle size = standard deviation of volume-converted particle size / average value of volume-converted particle size Similarly, from the above measurement, the variation coefficient of the area-converted particle size of silver halide grains can be determined. Here, the variation coefficient of the area-converted particle diameter is a value defined by the following equation.

The coefficient of variation of the area-converted grain size of the silver halide grains according to the present invention is preferably 0.2 or less, more preferably 0.1 or less. The coefficient of variation of the area-converted particle size = the standard deviation of the area-converted particle size / the average value of the area-converted particle size In any case of the volume-converted particle size or the area-converted particle size, the smaller variation coefficient is the object of the present invention. It is easy to obtain high contrast, and it is easy to obtain the effect of the configuration of the present invention with respect to scratch resistance and fingerprint trace resistance.

The silver halide emulsion used in the present invention has an average aspect ratio (hereinafter simply referred to as aspect ratio) of at least 50% of the total projected area of the silver halide grains contained in the silver halide emulsion. 0.030 to 30 tabular grains, more preferably 50% or more of the total projected area are tabular grains having an aspect ratio of 4 to 20.
Particularly, tabular grains having an aspect ratio of 5 to 15 are preferable.

It is preferable that 80% or more of the total projected area of the silver halide grains contained in the silver halide emulsion is the above-mentioned tabular grains.

The tabular silver halide grains according to the present invention are:
It has one or two or more twin planes parallel to each other in the grains, but preferably at least 50% of the tabular grains are tabular grains having two twin planes parallel to each other in the grains, More preferably, it is at least 80%. These twin planes can be observed with a transmission electron microscope.

The specific method is as follows. First, a silver halide emulsion is applied on a substrate so that the main plane of the contained tabular grains is oriented substantially parallel to the substrate to prepare a sample. This is continuously cut perpendicular to the substrate using a diamond cutter to obtain a continuous thin section having a thickness of about 0.1 μm. By observing this section with a transmission electron microscope, the existence and position of the twin plane can be confirmed.

The composition of the silver halide grains is preferably silver iodobromide, silver bromide, silver chlorobromide, or silver chloroiodobromide. In particular, it is preferably silver iodobromide having an average silver iodide content of 2 mol% or less, more preferably 1 mol% or less, particularly preferably 0.5 mol% or less. preferable. The composition of silver halide grains is determined by EPMA method, X
It can be examined using a composition analysis method such as a line diffraction method.

The average silver iodide content of the surface phase of the silver halide grains is preferably 3 mol% or less, and 0.1 to 2 mol%.
Mol% is more preferable, and 0.2 to 1 mol% is still more preferable. The average silver iodide content of the surface phase of the silver halide grains referred to herein is a value obtained by using the XPS method or the ISS method. For example, the surface silver iodide content by the XPS method can be obtained as follows.

That is, the sample was cooled to −155 ° C. or less in an ultra-high vacuum of 1.33 × 10 ⁻² Pa or less,
Irradiate MgKa as an X-ray at an X-ray source current of 40 mA,
The measurement is performed on 3d5 / 2, Br3d, and I3d3 / 2 electrons. The integrated intensity of the measured peak is corrected by a sensitivity factor, and the composition such as the silver iodide content of the silver halide surface phase is determined from these intensity ratios.

The silver halide emulsion used in the present invention comprises:
It is preferable that the silver iodide content between silver halide grains is more uniform. That is, the coefficient of variation of the silver iodide content is 30%.
Or less, more preferably 20% or less. However, the coefficient of variation here is
It is a value obtained by dividing the standard deviation of the silver iodide content by the average value of the silver iodide content and multiplying by 100, and can be used to arbitrarily measure 500 or more silver halide grains contained in the silver halide emulsion. Say the value given.

It is preferable to use a production method in which an aqueous solution containing a salt is appropriately extracted from the reaction solution by an ultrafiltration device. For example, the average intergranular distance in the growth process of silver halide grains is set to 0.
It is preferably controlled to 60 to 1.00 times, and 0.60 to 1.00.
More preferably, it is controlled to 0.80 times. Specifically, the value of the average interparticle distance is preferably controlled to 3.2 μm or less, more preferably to 2.8 μm or less, and particularly preferably to 0.90 to 2.0 μm.

As a preparation form of the silver halide emulsion, a method known in the art can be appropriately applied. For example, a so-called controlled double jet method or controlled triple jet method for controlling pAg of a reaction solution at the time of forming silver halide grains can be used.
A silver halide solvent can be used if necessary. Examples of useful silver halide solvents include ammonia, thioethers and thioureas. Regarding thioethers, U.S. Pat. Nos. 3,271,151, 3,790,387, and 3,574,626 can be referred to. The method for preparing silver halide grains is not particularly limited, and an ammonia method, a neutral method using no ammonia, an acidic method, and the like can be used.
From the viewpoint that fogging during silver halide grain formation can be suppressed, it is preferable to form grains in an environment where the pH (the logarithm of the reciprocal of the hydrogen ion concentration) is 5.5 or less, more preferably 4.5 or less. .

The metal ions doped into the tabular silver halide grains are rhodium, ruthenium, rhenium and osmium. One of these may be used in combination of two or more of the same or different metal complexes.

These metal ions are used as a single salt or a metal complex. As the simple salt, halide (chloride, bromide, etc.), nitrate, sulfate and perchlorate are preferably used, and as the metal complex, 6-coordinate, 5-coordinate, 4
A coordination or bicoordination complex can be used, and the complex may be a mononuclear complex or a polynuclear complex. The preferred content of metal ions is 1 × 10 ^-10 to 1 × 1 per mole of silver.
The range of ^0-7 mol is preferable, and 5 * 10 < ^-10 > to 1 * 10 < ^-8 >
Molar is more preferred.

The metal complex is preferably a six-coordinate complex or a complex ion represented by the following general formula. In the formula [ML ₆ ] ^m , M represents a metal ion selected from Rh, Ru, Re, and Os, L represents a bridging ligand, and m represents 0, 1-, 2-, 3-, or 4-. Specific examples of the ligand represented by L include halides (fluoride, chloride, bromide and iodide), cyanide, cyanate, thiocyanate, selenocyanate, tellurocyanate, azide and aquo. Ligand,
Nitrosyl, thionitrosyl and the like can be mentioned, and preferred are aquo, nitrosyl and thionitrosyl. If an aquo ligand is present, it preferably occupies one or two of the ligands. A plurality of L may be the same or different.

Specific examples are shown below, but the present invention is not limited to these examples. 1: [RhCl _6] ^3- 2: [RhCl ₅ (H ₂ O)] ^2- 3: [Rh (NO) ₂ Cl _4] ^- 4: _{[Rh (NO) (H 2 O} ) Cl 4 ] ^- 5 : [Rh (NS) Cl _5] ^2- 6: [RuCl _6] ^3- 7: [RuBr _6] ^3- 8: [Ru (NO) Cl _5] ^2- 9: [Ru (NO) (H ₂ O ) Cl _4] ^- 10: [Ru (NS) Cl _5] ^2- 11: [RuBr ₄ (H ₂ O)] ^2- 12: [Ru (NO) CN _5] ^2- 13: [ReCl _6] ^3- 14: [Re (NO) Cl _5] ^2- 15: [Re (NO) CN _5] ^2- 16: [Re (NO) ClCN _4] ^2- 17: [Re (NO) Cl _5] ^- 18: [ _{Re (NS) Cl 4 (SeCN} ) ] ^2- 19: [OsCl _6] ^3- 20: [Os (NO) Cl _5] ^2- 21: _{[Os (NS) Cl 4 (TeCN} ) ] ^2- 22: [ Os (NS) Cl (S N) _4] ^2- These metal complexes preferably used as the complex of potassium, sodium, ammonium salts or cesium salts.

It is preferable that the compound supplying these metal ions or complex ions is added during silver halide grain formation and incorporated into silver halide grains. Preparation of silver halide grains, that is, nucleation and growth , Physical aging,
It may be added at any stage before and after the chemical sensitization, but is particularly preferably added at the stage of nucleation, growth and physical ripening, and more preferably at the stage of nucleation and growth.

In the addition, it may be divided and added several times, or may be added uniformly in silver halide grains.
306236, 3-167545, 4-765
As described in JP-A Nos. 34, 6-110146, 5-273683, and the like, they can be contained in the particles with a distribution.

These metal compounds can be added by dissolving them in water or a suitable organic solvent (alcohols, ethers, glycols, ketones, esters, amides, etc.). A method in which an aqueous solution or an aqueous solution in which a metal compound is dissolved together with sodium chloride and potassium bromide is added to a water-soluble silver salt solution or a water-soluble halide solution during grain formation, or a silver salt solution and a halide solution Are mixed at the same time, a third aqueous solution is added, a method of preparing silver halide grains by a three-liquid simultaneous mixing method, a method of charging a required amount of an aqueous solution of a metal compound into a reaction vessel during grain formation, Alternatively, there is a method of adding another silver halide grain doped with a metal ion or a complex ion in advance and dissolving the silver halide during the preparation of the silver halide. In particular, a method of adding an aqueous solution of a metal compound or an aqueous solution in which a metal compound and sodium chloride and potassium bromide are dissolved together is added to a water-soluble halide solution. When adding to the particle surface, a required amount of an aqueous solution of a metal compound can be charged into the reaction vessel immediately after the formation of the particles, during or at the end of physical ripening, or at the time of chemical ripening.

The silver halide emulsion contains a dispersion medium together with silver halide grains. The dispersion medium is a compound having a protective colloid property for silver halide grains, and is preferably present from the nucleation step to the end of grain growth. Preferred dispersion media include gelatin and protective colloid polymers.

As gelatin, a molecular weight of usually 100,
About 000 alkali-treated gelatin or acid-treated gelatin,
Alternatively, low molecular gelatin or oxidized gelatin having a molecular weight of about 5,000 to 30,000 can be preferably used. In particular, at the time of nucleation, oxidized gelatin, low molecular weight gelatin, and oxidized low molecular weight gelatin can be suitably used.

Incidentally, in the silver halide emulsion of the present invention, the technique described in RD308119 can be used.

The silver halide grains can be subjected to chemical sensitization by a commonly used method. Chemical ripening, ie, the conditions of the process of chemical sensitization, such as pH, pAg, temperature,
There is no particular limitation on the time and the like, and the reaction can be performed under conditions generally performed in the art.

Chemical sensitization includes a sulfur sensitization method using a compound containing sulfur capable of reacting with silver ions or active gelatin, a selenium sensitization method using a selenium compound, a tellurium sensitization method using a tellurium compound, a reducing substance , A noble metal sensitization method using a noble metal, and the like. These methods may be used alone or in combination. Among them, selenium sensitization, tellurium sensitization, reduction sensitization, and the like are preferably used, and selenium sensitization is particularly preferably used.

Examples of useful selenium sensitizers include colloidal selenium metal, isoselenocyanates (such as allyl isoselenocyanate), and selenoureas (N, N
Dimethylselenourea, N, N, N'-triethylselenourea, etc., selenoketones (selenoacetone, selenoacetophenone, etc.), selenoamides (selenoacetamide, N, N-dimethylselenobenzamide, etc.), selenocarboxylic acids and seleno Esters (such as 2-selenopropionic acid and methyl-3-selenobutyrate), selenophosphates (such as tri-p-triselenophosphate), and selenides (diethylselenide, diethyldiselenide, and triphenylphosphineselenide) Etc.). Particularly preferred selenium sensitizers are selenoureas, selenamides and selenoketones.

The amount of the selenium sensitizer used depends on the selenium compound used, silver halide grains, chemical ripening conditions and the like, but is generally 10 ^-8 to 10 per mol of silver halide.
^{It is} preferable to use about ^-4 mol. Depending on the properties of the selenium compound to be used, the addition method may be a method in which the compound is dissolved in water or an organic solvent such as methanol, ethanol, or ethyl acetate alone or in a mixed solvent, or a method in which the compound is previously mixed with a gelatin solution and added. Or JP-A-4-14073.
No. 9, that is, a method of adding in the form of an emulsified dispersion of a mixed solution with an organic solvent-soluble polymer.

The silver halide grains may be spectrally sensitized with methine dyes or the like. Dyes used include cyanine dyes, merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine dyes, hemicyanine dyes, styryl dyes, and hemioxonol dyes. Particularly useful dyes are those belonging to the cyanine dyes, merocyanine dyes and complex merocyanine dyes.

As these dyes, any of the nuclei usually used can be applied. That is, pyrroline, oxazoline,
Thiazoline, pyrrole, oxazole, thiazole, selenazole, imidazole, tetrazole, pyridine nucleus and the like, these nuclei are fused with an aliphatic hydrocarbon ring,
That is, indolenine, benzindolenin, indole,
Benzoxazole, naphthoxazole, benzothiazole, naphthothiazole, benzoselenazole, benzimidazole, quinoline nucleus and the like can be applied. These nuclei may have substituents on carbon atoms.

The merocyanine dye or the complex merocyanine dye includes pyrazoline- as a nucleus having a ketomethine structure.
5- to 6-membered heterocyclic nuclei such as 5-one, thiohydantoin, 2-thiooxazolidine-2,4-dione, thiazoline-2,4-dione, rhodanine and thiobarbituric acid nuclei can be applied.

The sensitizing dyes particularly useful in the present invention are trimethine cyanine dyes which give spectral sensitivity to green light, and specifically include oxalates described in JP-A-7-28184, pp. 2-12. It is a carbocyanine dye or a benzimidazolocarbocyanine dye.

These sensitizing dyes may be used alone or in combination, and the combination is often used particularly for supersensitization. The emulsion layer may contain a dye having no spectral sensitization or a substance which does not substantially absorb visible light and exhibits supersensitization, together with the sensitizing dye. For example, a substituted aminostilbene compound which is a nitrogen-containing heterocyclic nucleus (US Pat. No. 2,933,390)
No. 3,635,721) and an aromatic organic acid formaldehyde condensate (US Pat. No. 3,743,51).
No. 0), cadmium salts, azaindene compounds and the like. US Patent 3,615,613
Nos. 3,615,641 and 3,617,295
Nos. 3,635,721 and the like are particularly useful.

The sensitizing dye may be added during or during each of the steps of nucleation, growth, desalting, and chemical sensitization, or after the chemical sensitization.

Next, the polymer particles according to claim 1 of the present invention will be described. The polymer particles of the present invention have a relative standard deviation (standard deviation of the particle diameter of the polymer particles / average particle diameter) of 10% or less. Here, the average particle diameter is a number average particle diameter. The average particle size of these polymer particles is preferably 1 to 10 μm, more preferably 2 to 6 μm.
μm. If it is less than 1 μm, the effect of preventing crackling is deteriorated, and if it is more than 10 μm, peeling is liable to occur and abrasion becomes worse. The relative standard deviation is preferably 8% or less, more preferably 7% or less. If the relative standard deviation is too large, coarse particles are mixed and peeling easily occurs. The average particle diameter and the relative standard deviation in the present invention can be determined by taking an electron micrograph of polymer particles and randomly measuring 500 or more particle diameters from the photograph.

The content of the polymer particles is 1 to 300 mg.
/ M ² · one side, more preferably 5
200 mg / m ² · one side, particularly preferably 10 to 10
0 mg / m ² · one side.

The glass transition point (Tg) of the polymer compound used as the polymer particles is preferably 40 ° C. or higher. Among them, Tg is preferably 50 ° C. or higher, more preferably 60 ° C. or higher. If the Tg is less than 40 ° C., the blocking property in an environment at an air temperature of 40 ° C. or more deteriorates, which is not preferable.

The refractive index of the polymer particles is preferably close to the refractive index of the binder of the layer containing the polymer particles, preferably within ± 0.5, more preferably within ± 0.3 of the refractive index of the binder. , More preferably within ± 0.1. When the refractive index of the polymer particles is out of the range of ± 0.5 with respect to the refractive index of the binder of the layer containing the polymer particles, it becomes a factor of deteriorating the transparency.

The polymer particles can be used as a mixture of two or more kinds. Further, the polymer particles of the present invention are preferably spherical, and when the diameter of the polymer particles is measured using an electron micrograph, the ratio of the major axis / minor axis in the same particle is usually 1.2 or less, preferably Is 1.1 or less.

As the polymer particles, a polymer compound synthesized by a seed polymerization method, a soap-free polymerization method, a suspension polymerization method, or a spherical polymer compound formed by a spray drying method or a dispersion method can be used. Among them, the seed polymerization method is preferable, and the method described in JP-A-8-120005 is particularly preferable.

In order to polymerize a monomer onto a seed particle by the seed polymerization method, a monomer, a polymerization initiator and an emulsifier are charged into an aqueous medium to be emulsified, and the seed particle is charged into this emulsion to carry out polymerization. Let it.

The seed particles can be formed of various resins. Specific examples of the resin forming the seed particles include a (meth) acrylic resin, a styrene resin, a mixed resin of a (meth) acrylic resin and a styrene resin, or a (meth) acrylic monomer and styrene. A copolymer with a system monomer can be mentioned. Further, the (meth) acrylic resin or the styrene resin includes, as described above, another monomer copolymerizable with the (meth) acrylate ester monomer and / or the styrene monomer. May be copolymerized. Examples of such a monomer include a vinyl monomer and an unsaturated carboxylic acid monomer.

As the (meth) acrylic resin, a (co) polymer of (meth) acrylate or (meth) acrylic ester
It is preferably a copolymer of an acrylic ester monomer and another monomer. Examples of (meth) acrylate monomers include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, Lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-propyl (meth) acrylate, chloro-2-hydroxyethyl (meth) acrylate, diethylene glycol mono Examples thereof include (meth) acrylate, methoxyethyl (meth) acrylate, glycidyl (meth) acrylate, dicyclopentanyl (meth) acrylate, and dicyclopentenyl (meth) acrylate.

Examples of the styrene monomer forming the seed particles include styrene, methylstyrene, di- or trimethylstyrene, ethylstyrene, di- or triethylstyrene, propylstyrene, butylstyrene, hexylstyrene, heptylstyrene. And styrene such as fluorostyrene, chlorostyrene, bromostyrene, dibromostyrene and chloromethylstyrene; and nitrostyrene, acetylstyrene and methoxystyrene.

The seed particles may contain, for example, (meth) acrylic acid ester in an amount of usually 0 to 100 parts by mass, preferably 50 to 100 parts by mass.
100 parts by weight, usually 0 to 80 parts by weight, preferably 0 to 50 parts by weight of a styrene monomer, and 0 to 80 parts by weight, preferably 0 to 80 parts by weight of another monomer such as a vinyl monomer. ~ 50
It can be copolymerized in parts by weight.

The seed particles preferably used in the present invention have a crosslinked structure. The gel fraction of the seed particles by the toluene extraction method is in the range of 10 to 85%, and more preferably 30 to 70%. Is preferably within the range.

To adjust the gel fraction of the seed particles,
A crosslinked structure is formed using a functional or polyfunctional monomer. Examples of these monomers include ethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, and pentaerythritol tri (meth) acrylate.
Examples include acrylate, 1,1,1-trishydroxymethylethane diacrylate, 1,1,1-trishydroxymethylethane triacrylate, 1,1,1-trishydroxymethylpropane triacrylate, and divinylbenzene.

In forming the seed particles, the bifunctional monomer or the polyfunctional monomer is usually used in an amount of 0.005 to 0.05 part by mass, preferably 100 to 0.05 part by mass, per 100 parts by mass of the monomer. Is used in an amount of 0.01 to 0.04 parts by mass.

The seed particles can be prepared by various methods such as soap-free emulsion polymerization, suspension polymerization and emulsion polymerization. In the present invention, soap-free emulsion polymerization is particularly preferred.

Examples of the polymerization initiator used in the soap-free emulsion polymerization include persulfates such as potassium persulfate and ammonium persulfate. The polymerization initiator soluble in the aqueous medium used in the polymerization is used. It is not limited to these as long as it is an initiator. The polymerization initiator is usually used in an amount of 0.1 to 10 parts by mass based on 100 parts by mass of the monomer used.

The seed particles thus formed are usually in the range of 0.05 to 1 μm, preferably 0.2 to 0.6 μm.
Average particle size. The relative standard deviation of the particle size is usually 10% or less, preferably 5% or less.

The next polymerization step is usually carried out by blending seed particles, monomers and a polymerization initiator, and if necessary, an emulsifier and a dispersion stabilizer in an aqueous medium. The monomer used in this polymerization step is the monomer listed in the description of the production of the seed particles, and may be the same as or different from the monomer that formed the seed particles.

Examples of the polymerization initiator used for the seed polymerization include persulfates such as potassium persulfate and ammonium persulfate; peroxides such as benzoyl peroxide and lauryl peroxide;
An azo compound such as azobisisobutyronitrile can be used. The polymerization initiator is usually used in an amount of 0.1 to 10 parts by mass based on 100 parts by mass of the monomer.

Examples of the emulsifier include alkylbenzene sulfonates such as sodium dodecylbenzenesulfonate, and polyethylene glycol alkyl ethers such as polyethylene glycol nonylphenyl ether. The emulsifier is usually used in an amount of 0.1 to 5 parts by mass based on 100 parts by mass of the monomer.

Examples of dispersion stabilizers include partially saponified polyvinyl alcohol, polyvinyl alcohol, poly (meth) acrylic acid, copolymers thereof, and neutralized products thereof. The dispersion stabilizer is usually used in an amount of 0.1 to 5 parts by mass with respect to 100 parts by mass of the monomer.

By going through the above polymerization step,
The monomers absorbed by the seed particles polymerize and the seed particles grow. Usually, the polymerization of the second and subsequent stages is performed so as to be 2 to 100 times the mass of the seed particles. The second and subsequent polymerization steps are usually repeated 1 to 10 times, preferably 1 to 5 times. In the final stage, the particles produced in the polymerization step immediately before being used as seed particles have a crosslinked structure, and the seed particles have a gel fraction of 10 to 85% by a toluene extraction method. Use
Further, the gel fraction is preferably in the range of 30 to 70%.

In order to adjust the gel fraction of the seed particles in the final stage, a bifunctional or polyfunctional monomer can be used as in the case of the seed particles in the first stage.

A production example of the polymer particles (P-1) of the present invention is shown (in the production examples, “parts” represents “parts by mass”).

(Preparation of Seed Particles) A one-liter four-necked flask equipped with a thermometer and a nitrogen inlet tube was charged with 100 parts of methyl methacrylate as a monomer and ethylene glycol dimethacrylate as a crosslinkable monomer. 0.04
And 900 parts of ion-exchanged water were added and mixed, and the temperature was raised to 80 ° C. while stirring under a nitrogen stream. Next, 0.2 parts of potassium persulfate is dissolved in 5 parts of ion-exchanged water, added to the reaction solution in the four-necked flask, and reacted at 80 ° C. for 6 hours to obtain a dispersion of seed particles. Obtained.

When observed by an electron micrograph, the seed particles had a particle size of 0.50 μm and a standard deviation of 0.5 μm.
03 μm. The gel fraction obtained by the toluene extraction method was 80%.

(Second Stage Polymerization) In a device similar to the above, 100 parts of methyl methacrylate as a monomer was mixed with 0.0 of ethylene glycol dimethacrylate as a crosslinkable monomer.
3 parts and 0.2 parts of benzoyl peroxide were added and dissolved, and further, 1 part of sodium dodecylbenzenesulfonate and 900 parts of ion-exchanged water in which 1 part of saponified polyvinyl alcohol was dissolved were mixed with 900 parts of strong solution. 30 with stirring
Mixing was performed for minutes.

Next, 33 parts of the above-mentioned seed particle dispersion was added to the above mixture, and the mixture was gently stirred at 40 ° C. for 30 minutes and then reacted at 80 ° C. for 6 hours to obtain a dispersion of polymer particles. .

The average particle size of the obtained polymer particles was 1.2.
0 μm with a standard deviation of 0.05 μm. or,
The gel fraction obtained by the toluene extraction method was 60%.

Next, 95 parts of methyl methacrylate as a monomer, 5 parts of ethylene glycol dimethacrylate and 0.2 part of benzoyl peroxide as crosslinkable monomers were mixed in a similar apparatus. And dissolved in this solution with 1 part of sodium dodecylbenzenesulfonate and 88%
After adding and mixing 900 parts of ion-exchanged water in which 1 part of saponified polyvinyl alcohol was dissolved, the mixture was mixed for 30 minutes under strong stirring.

Next, 20 parts of the seed emulsion obtained in the second stage was added to the mixture, and the mixture was gently stirred at 40 ° C. for 30 minutes, and then reacted at 80 ° C. for 6 hours to disperse the polymer particles. A liquid was obtained.

Observation with an electron microscope photograph revealed that the particles were truly spherical monodisperse particles having an average particle diameter of 4.4 μm and a standard deviation of 0.20 μm, and a relative standard deviation of 4.5%.

Next, the polymer particles according to claim 2 of the present invention will be described. The polymer particles have an average particle size of 1
It is a copolymer having a particle size of 10 to 10 μm and comprising 5 to 15% of an acidic monomer and at least one or more nonionic monomers. The average particle diameter and the relative standard deviation mentioned here are the same as those described for the polymer particles according to the first aspect. The average particle size of the polymer particles is preferably 2 to 9 μm.
m, more preferably 3 to 8 μm.

Examples of the acidic monomer include acrylic acid, methacrylic acid, itaconic acid, maleic acid, styrenesulfonic acid, vinylbenzylsulfonic acid, vinylsulfonic acid, acryloyloxyalkylsulfonic acid (acryloyloxymethylsulfonic acid, etc.), methacryloyloxyalkyl Sulfonic acid (such as methacryloyloxyethylsulfonic acid), acrylamidoalkylsulfonic acid (such as 2-acrylamido-2-methylethanesulfonic acid), methacrylamidoalkylsulfonic acid (such as 2-methacrylamido-2-methylethanesulfonic acid), and acryloyl Oxyalkyl phosphates (such as acryloyloxyethyl phosphate) are exemplified. These acids may be salts of alkali metals (sodium, potassium, etc.) or ammonium ions. Acrylic acid and methacrylic acid are preferred, and methacrylic acid is particularly preferred.

The content of the acidic monomer is 5 to 15 mol%, preferably 7 to 12 mol% of the total monomer components. If the content of the acid component is more than 15 mol%, it will be dissolved at the time of development processing, and if it is less than 5 mol%, it will be easily peeled off.

Examples of the nonionic monomer copolymerized with the acidic monomer include (meth) acrylic acid ester, itaconic acid diester, crotonic acid ester, maleic acid diester, and phthalic acid diester. , Methyl, ethyl, propyl, i-propyl, butyl, hexyl, 2-ethylhexyl, 2-chloroethyl, cyanoethyl, 2-acetoxyethyl, dimethylaminoethyl, benzyl, cyclohexyl, furfuryl, phenyl, 2-hydroxyethyl, 2-ethoxy Ethyl, glycidyl, ω-methoxypolyethyleneoxy and the like. In addition, vinyl esters, olefins, styrenes, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl ketones, vinyl heterocyclic compounds, unsaturated nitriles and the like are also used. Further, monoalkyl itaconate (monoethyl itaconate, etc.), monoalkyl maleate (monomethyl maleate, etc.), and N- (2-acetoacetoxyethyl) acrylamide, N- (2- (2
-Acetoacetoxyethoxy) ethyl) acrylamide, divinylbenzene, ethylene glycol dimethacrylate and the like. In these monomers,
(Meth) acrylates, vinyl esters, styrenes, and olefins are preferably used, and particularly preferred are methyl methacrylate and ethyl methacrylate. Also, JP-A Nos. 62-14647 and 62-1
Particles having a fluorine atom or a silicon atom as described in JP-A Nos. 7744 and 62-17743 may be used.

Particularly preferred among the polymer particles of the present invention are those containing (meth) acrylic acid and esters thereof in an amount of 80% by mass or more in terms of the composition of the polymer particles.
In that case, vinyl esters, olefins, styrenes, acrylamides, methacrylamides, allyl compounds, vinyl ethers at a mass ratio of 20% by mass or less,
Vinyl ketones, vinyl heterocyclic compounds, unsaturated nitriles and the like are used. Preferred are styrene and styrene derivatives. As a preferred embodiment of the polymer particles,
Methyl methacrylate / acrylic acid copolymer (95/5 to 5
85/15 (molar ratio)), methyl methacrylate / methacrylic acid copolymer (95/5 to 85/15 (molar ratio)),
Ethyl methacrylate / methacrylic acid copolymer (95/5
-85/15 (molar ratio)), and more preferably, methyl methacrylate / acrylic acid copolymer (93 / 7-8).
8/12 (molar ratio)), methyl methacrylate / methacrylic acid copolymer (93/7 to 88/12 (molar ratio)), and ethyl methacrylate / methacrylic acid copolymer (93/7
８８88/12 (molar ratio)).

5 to 15% of the acidic monomer and at least 1
The polymer particles of the present invention, which are copolymers of at least one kind of nonionic monomer, are preferably monodisperse, and preferably have a relative standard deviation of 30% or less, more preferably 20% or less.

After polymerization, the polymer particles may be classified and monodispersed. As a classification means, a centrifugal separation method can be used. That is, diluting the dispersion of polymer particles,
The particles are set in a centrifuge and settled out according to the rotation speed of the centrifuge. By repeating this operation several times, the monodispersity can be improved. Examples of the monodispersion by polymerization include soap-free polymerization, suspension polymerization, seed polymerization, molecular diffusion, two-stage swelling, dynamic swelling, accelerated diffusion polymerization, and dispersion polymerization. For example, a known method is used.

Hereinafter, specific examples of the polymer particles of the present invention will be described (these are classified by centrifugation).

Composition ratio Average particle size Relative standard deviation (μm) (%) P-2 MMA: AA (90:10) 4.5 30 P-3 MMA: MAA (90:10) 4.5 20 P- 4 EMA: AA (85:15) 4.6 30 P-5 MMA: AA (95: 5) 4.5 20 P-6 EMA: MAA (90:10) 4.4 20 where MMA = methyl methacrylate , EMA = ethyl methacrylate, AA = acrylic acid, MAA = methacrylic acid.

Next, the polymer particles according to claim 3 of the present invention will be described. The polymer particles are polymer particles obtained by copolymerizing a nonionic ethylenically unsaturated monomer with a non-anionic ethylenically unsaturated monomer.

The nonionic ethylenically unsaturated monomer is an ethylenically unsaturated monomer having a hydroxyl group, an alkylene oxide group and an amide group in the molecule. Preferably, it is an acrylic or methacrylic unsaturated monomer having a hydroxyl group or an alkylene oxide group. Among them, a monomer represented by the general formula (M) is preferable.

[0092]

Embedded image

In the formula, R represents a hydrogen atom or a methyl group,
A represents a divalent group. Preferred examples of the nonionic ethylenically unsaturated monomer represented by the general formula (M) are shown below, but are not limited thereto.

[0094]

Embedded image

[0095]

Embedded image

The ethylenically unsaturated monomer other than anionic which can be copolymerized with the nonionic ethylenically unsaturated monomer used in the present invention is not particularly limited. Examples thereof include acrylates (t-butyl acrylate, phenyl acrylate, 2-naphthyl acrylate, etc.), methacrylates (methyl methacrylate, ethyl methacrylate, benzyl methacrylate, phenyl methacrylate, cyclohexyl methacrylate, cresyl methacrylate, 4-chlorobenzyl methacrylate, ethylene glycol dimethacrylate, glycidyl methacrylate, etc.), vinyl esters (Vinyl benzoate, pivaloyloxyethylene, etc.), acrylamides (acrylamide, methylacrylamide, ethylacrylamide, propylene) Acrylamide, butyl acrylamide, t- butyl acrylamide, cyclohexyl acrylamide, benzyl acrylamide, hydroxymethyl acrylamide, methoxyethyl acrylamide,
Dimethylaminoethyl acrylamide, phenyl acrylamide, dimethyl acrylamide, diethyl acrylamide, β-cyanoethyl acrylamide, diacetone acrylamide, etc., methacrylamides (methacrylamide, methyl methacrylamide, ethyl methacrylamide, propyl methacrylamide, butyl methacrylamide, t- Butyl methacrylamide, cyclohexyl methacrylamide, benzyl methacrylamide, hydroxymethyl methacrylamide, methoxyethyl methacrylamide, dimethylaminoethyl methacrylamide, phenyl methacrylamide, dimethyl methacrylamide, diethyl methacrylamide, β-cyanoethyl methacrylamide, etc.), styrenes (Styrene, methylstyrene,
Dimethylstyrene, trimethylenestyrene, ethylstyrene, i-propylstyrene, chlorostyrene, methoxystyrene, acetoxystyrene, chlorostyrene, dichlorostyrene, bromostyrene, vinyl benzoate methyl ester, etc.), divinylbenzene, acrylonitrile, methacrylonitrile , N-vinylpyrrolidone, N
-Vinyl oxazolidone, vinylidene chloride, phenyl vinyl ketone and the like.

Further, a crosslinkable ethylenically unsaturated monomer may be used, for example, ethylene glycol diacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate. , Trimethylolpropane triacrylate, 1,4-butanediol diacrylate, 1,6
-Hexanediol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol dimethacrylate,
Pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, glycerol dimethacrylate, glycerol diacrylate, glycerol acryloxy dimethacrylate, 1,1,1-trishydroxymethylethane diacrylate, 1,1,1-trishydroxymethylethane triacrylate 1 , 1,
1-trishydroxymethylethane dimethacrylate,
1,1,1-trishydroxymethylethanetrimethacrylate, 1,1,1-trishydroxymethylethanetrimethacrylate, 1,1,1-trishydroxymethylpropane diacrylate, 1,1,1-trishydroxymethylpropanedita Acrylate, 1,1,1-trishydroxymethylpropane trimethacrylate, triallyl cyanurate, triallyl isocyanurate,
Triallyl trimellitate, diallyl terephthalate,
Diallyl phthalate and divinyl benzene;

These ethylenically unsaturated monomers may be used alone or in combination.

The glass transition temperature (Tg) of the polymer particles of the present invention can be appropriately selected depending on the application, but is preferably 40 ° C. or higher, more preferably 70 ° C. or higher.

The average particle size of the polymer particles is preferably 1
10 μm, more preferably 2 to 6 μm.

The method for producing the polymer particles is not particularly limited as long as the polymer particles can be formed, but a suspension polymerization method for polymerizing a suspension of an ethylenically unsaturated monomer in an aqueous medium is preferred.

In the suspension polymerization, a hydrophilic colloid such as gelatin, polyvinylpyrrolidone, polyvinyl alcohol and starch is added. Typical polymerization initiators are peroxides and azo initiators, such as 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (isobutyronitrile), Lauroyl peroxide, benzoyl peroxide and the like. Further, a chain transfer agent can be added to the monomer as needed. Other suspension stabilizers include anionic fine particle suspension stabilizers (silica,
Clay, talc, etc.), anionic, cationic and nonionic surfactants (sulfonated alkylaryl polyethers, ethylene glycol ethers of polyhydric alcohols, carboxyalkyl-substituted polyglycol ethers and esters, condensation products of naphthalenesulfonic acid with formaldehyde) Sodium salt, glycidol polyether phosphate, higher alcohol sulfate, water-soluble salt of sulfosuccinic acid fatty acid ester, hydroxyalkylsulfonic acid fatty acid ester, sulfoacetic acid amide and ester derivative, fatty acid α-sulfo lower alkyl ester As well as sulphate products of glycidol polyethers).

As the polymerization process, a suspension of the ethylenically unsaturated monomer may be prepared in advance and then heated to carry out the polymerization, or the polymerization may be carried out while the ethylenically unsaturated monomer is suspended in an aqueous medium. .

Here, specific examples of the polymer particles used in the present invention will be described, but the present invention is not limited thereto (these are classified by centrifugation).

Composition ratio Average particle size Relative standard deviation P-7 M1: MMA = 5: 95 4.2 μm 30% P-8 M1: MMA = 7: 93 4.4 μm 28% P-9 M1: MMA = 10 : 90 4.3 μm 30% P-10 M1: St = 5: 95 4.5 μm 27% P-11 M1: BT = 5: 95 4.3 μm 25% P-12 M1: MMA: LMA = 6: 92: 2 4.2 μm 30% P-13 M4: MMA = 5: 95 4.4 μm 29% P-14 M8: MMA = 10: 90 4.3 μm 30% where MMA = methyl methacrylate, St = styrene, BT = Vinyl toluene, LMA = lauryl methacrylate Next, the layer constitution in the photosensitive material of the present invention will be described.

The light-sensitive material of the present invention has at least one light-sensitive silver halide emulsion layer on one side of a support and a backing layer on the other side. Use plastic base. For example, cellulose triacetate (TAC), polyester (PET, PEN)
Etc.) and polystyrene (SPS etc.) can be used. The main object of the present invention is to use a photosensitive material for medical diagnosis of 160 to 180 μm in order to obtain rigidity in handling.
PET (polyethylene terephthalate) with a thickness of m
A base is preferred.

The support may be colored in a range where the transparency is maintained. By coloring the support in blue at a concentration of about 0.1 to 0.2, eye fatigue in observation of a transmission image by sharksten is reduced. It is preferable because it is possible. The support is usually subjected to a subbing treatment in order to provide adhesion between the constituent layer coated on the support and the support.

The constituent layers on the side having the photosensitive silver halide emulsion layer include a conductive layer (antistatic layer), an intermediate layer, a filter dye layer, a protective layer and the like in addition to the photosensitive silver halide emulsion layer. Is also good. The dry thickness of the protective layer is preferably 0.4 to 1.0 μm, more preferably 0.5 to 0.8 μm.
μm is preferred. Examples of the additive to be added to the protective layer include Research Disclosure (Research) described later.
ch Disclosure (hereinafter referred to as RD) can be used.

The light-sensitive silver halide emulsion layer may be a single layer or a multi-layer, but one of the objects of the present invention is to provide a mammographic light-sensitive material having a multilayer structure in order to obtain a high contrast. It is preferred that the sensitivity be lower than the emulsion sensitivity of the lower layer. The contrast is preferably in the range of 3.6 or more and 4.7 or less. In this case, the sensitivity of the lower emulsion is 0.1 to 0.1 as a relative logarithmic sensitivity to the adjacent upper emulsion.
0.4 preferably high sensitivity, more preferably 0.15
It is preferably 0.3. The dry film thickness of the photosensitive silver halide emulsion layer is preferably from 2 to 4.6 μm as a total of all the photosensitive silver halide emulsion layers, and the ratio of the film thickness between the respective emulsion layers may be arbitrary. As additives to be added to the silver halide emulsion layer, those described in RD below can be used.

The total thickness of the photosensitive silver halide emulsion layer when dried is preferably 5 μm or less, more preferably 3.5 μm or less.

The layer structure on the backing layer side includes an antihalation dye layer, a protective layer and the like, but may further include a conductive layer (antistatic layer), an intermediate layer, and other dye layers in addition to these layers. . The antihalation dye layer preferably contains the aforementioned dye in a solid dispersion state. As the binder, gelatin, polymer latex and those described in RD below can be used. The total thickness of the backing layer when dried is preferably 5 μm or less, and more preferably 3.5 μm or less.

As additives to be added to these layers, those described in Research Disclosure (RD) described later can be used.

The photosensitive material is dried by adding an appropriate amount of a hardening agent in advance in the coating step of the photosensitive material so as to be suitable for rapid processing, and adjusting the swelling ratio in the developing-fixing-washing step. It is preferable to reduce the water content in the photosensitive material before the start.

The swelling ratio of the light-sensitive material of the present invention during the development processing is preferably 100 to 200%. The swelling ratio is obtained by calculating the difference between the film thickness after swelling in each processing solution and the film thickness before development processing, dividing the difference by the film thickness before processing and multiplying by 100.

Various photographic additives can be used in the light-sensitive material according to the present invention. Known additives include, for example, RD17643, page 23, section III to page 29, section XXI (197
December, 1981), pp. 18716, 648, upper right to p. 651, left (November 1979) and 308, 119, 996.
Compounds described in Sections III to 1009, Section XVII (December 1989) (chemical sensitizers, sensitizing dyes, desensitizing dyes, dyes, development accelerators, fog inhibitors / stabilizers, brighteners, hardeners) Filming agents, surfactants, antistatic agents, plasticizers, sliding agents, matting agents, binders, and supports).

As the preferred developing agents of the developing solution for developing the light-sensitive material of the present invention, JP-A-4-15641 and JP-A-4-15641 are used.
16841 and the like, dihydroxybenzenes (hydroquinone), paraaminophenols (p-aminophenol, N-methyl-p-aminophenol, 2,4
-Diaminophenol, etc.), 3-pyrazolidones (1-
Phenyl-3-pyrazolidone, 1-phenyl-4-methyl-4-hydroxymethyl-3-pyrazolidone, 5,5
-Dimethyl-1-phenyl-3-pyrazolidone, etc.) and the compound of the above general formula (I).

[0117]

Embedded image

In the general formula (I), R ₁ and R ₂ each represent a hydroxyl group, a mercapto group or an amino group (having 1 to 1 carbon atoms).
0, including those substituted with an alkyl group such as methyl, ethyl, butyl, hydroxyethyl group, etc.), acylamino group (acetylamino, benzoylamino, etc.), alkylsulfonylamino group (methanesulfonylamino, etc.), arylsulfonylamino Group (benzenesulfonylamino, p-toluenesulfonylamino, etc.), alkoxycarbonylamino group (methoxycarbonylamino, etc.), alkylthio group (methylthio, ethylthio group, etc.)
Represents

As R ₁ and R ₂ , preferred are a hydroxyl group, an amino group, an alkylsulfonylamino group and an arylsulfonylamino group.

Z is preferably composed of a carbon atom, an oxygen atom or a nitrogen atom, and forms a 5- to 6-membered ring together with two vinyl carbons substituted by R ₁ and R ₂ and a carbonyl carbon. Particularly, a reductone ring is preferable.

Specific examples of Z include -O-, -C
_{(R 3) (R 4)} -, - C (R 5) =, - C (= O) -,
-N (R ₆₎ -, - formed by combining the N =. However, R ₃ , R ₄ , R ₅ and R ₆ are each a hydrogen atom and a carbon atom 1
A substituted or unsubstituted alkyl group (e.g., a hydroxyl group, a carboxyl group, or a sulfo group), a substituted or unsubstituted aryl group having 6 to 15 carbon atoms (an alkyl group or halogen as a substituted group) Atoms, hydroxy, carboxy, and sulfo groups),
Represents hydroxyl and carboxyl groups. Furthermore, this 5
The 6-membered ring may form a saturated or unsaturated condensed ring.

Examples of the 5- or 6-membered ring include dihydrofuranone, dihydropyrone, pyranone, cyclopentenone,
Each ring of cyclohexenone, pyrrolinone, pyrazolinone, pyridone, azacyclohexenone, uracil and the like are mentioned, and preferred examples of the 5- or 6-membered ring include dihydrofuranone, cyclopentenone, cyclohexenone, pyrazolinone, azacyclohexenone and uracil. Each ring can be mentioned.

Specific examples of the compound represented by the general formula (I) of the present invention include sodium erythorbate, sodium ascorbate and JP-A-10-133338,
The compounds described on page 5 can be mentioned.

Preferred is a developer containing substantially no hydroquinone and a compound of the formula (I). In the present invention, substantially not contained means 0.1 g
/ Liter or less. General formula (I)
It is particularly preferable to use a compound represented by the formula (3) in combination with a 3-pyrazolidone.

The preservatives may include sulfites (potassium sulfite, sodium sulfite, etc.), reductones (piperidinohexose reductatone, etc.) and the like, preferably from 0.2 to 1 mol / l. And more preferably 0.3 to 0.6 mol / liter.
Also, addition of a large amount of ascorbic acids leads to processing stability. Sodium hydroxide,
PH adjusters such as potassium hydroxide, sodium carbonate, potassium carbonate, sodium tertiary phosphate and potassium tertiary phosphate are included. Further, buffers such as borate described in JP-A-61-28708 and saccharose, acetoxime, 5-sulfosalicylic acid, phosphate and carbonate described in JP-A-60-93439 may be used. The content of these chemicals is adjusted so that the pH of the developer is 8.5 to 11.5, preferably pH 9.5 to
Choose to be 10.5.

The dissolution aids may contain diethylene glycol, triethylene glycols and esters thereof, and the sensitizers may contain quaternary ammonium salts and other development accelerators, surfactants and the like.

As the silver sludge inhibitor, JP-A-56-1985
No. 106244, silver stain inhibitor, JP-A-3-518
The sulfides and disulfide compounds described in JP-A No. 44, and the cysteine derivatives or triazine compounds described in JP-A-5-289255 are preferably used.

As organic inhibitors, azole organic antifoggants such as indazole, imidazole, benzimidazole, triazole, benzotriazole, tetrazole, thiadiazole, mercaptoazole (1-phenyl-5-mercapto) Although compounds such as tetrazole are used, it is particularly preferable to use nitroindazole (5- or 6-nitroindazole). The preferable addition amount of nitroindazole is 0.002 to 0.2 g / liter, particularly preferably 0.01 to 0.1 g / liter.

As the inorganic inhibitor, sodium bromide, potassium bromide, potassium iodide and the like can be contained. In particular, the bromine ion concentration is preferably 10 g / liter or more in terms of potassium bromide.

In addition, L. F. A. Mason, "Photographic Processing Chemistry", Focal Press (1966), pp. 226-229, U.S. Pat. Nos. 2,193,015 and 2,592,364.
And those described in JP-A-48-64933.

Examples of the chelating agent for masking calcium ions mixed in tap water used in the treatment liquid include chelating agents having a chelate stabilization constant with iron of 8 or more described in JP-A-1-193853 as an organic chelating agent. It is preferably used. Examples of the inorganic chelating agent include sodium hexametaphosphate, calcium hexametaphosphate, and polyphosphate.

A dialdehyde compound may be used as a developing hardener. In this case, glutaraldehyde is preferably used.

The developing method according to the present invention is characterized in that it contains substantially no hydroquinones, contains the compound represented by the above general formula (I) and nitroindazole, and has a bromine ion concentration of potassium bromide. It is particularly preferable to use a developer having a conversion of 10 g / liter or more, so that a high-gradation and stable image, which is the object of the present invention, can be obtained.

The replenishment amount of the developing solution when developing the light-sensitive material of the present invention is 50 to 150 ml per m ² of the light-sensitive material.
Is preferable, and 65 to 130 ml is more preferable.

The fixing solution may contain a fixing agent generally used in the art. Examples of the fixing agent include thiosulfates such as ammonium thiosulfate and sodium thiosulfate, and ammonium thiosulfate is particularly preferable in view of the fixing speed. The concentration of the ammonium thiosulfate is preferably in the range of 0.1 to 5 mol / l, more preferably 0.8 to 5 mol / l.
３3 mol / liter.

The pH of the fixing solution is 3.8 or more, preferably 4.2 or more. In the present invention, the fixing solution may form an acidic film. In this case, an aluminum compound is preferably used as the hardener. For example, it is preferable to add in the form of aluminum sulfate, aluminum chloride, potash and the like.

The fixing solution may further contain a preservative such as a sulfite or a bisulfite, a pH buffer such as acetic acid or boric acid, a mineral acid (sulfuric acid, nitric acid) or an organic acid (citric acid, oxalic acid, PH adjusters such as various acids such as malic acid and hydrochloric acid, metal hydroxides (such as potassium hydroxide and sodium hydroxide), and chelating agents having the ability to soften hard water.

Examples of the fixing accelerator include, for example,
No. 35754, No. 58-122535, No. 58-12
No. 2536, thiourea derivatives, U.S. Pat.
Thioether described in US Pat. No. 6,459.

The amount of replenishment of the fixing solution for fixing the light-sensitive material of the present invention is from 50 to 150 ml per m ² of the light-sensitive material.
Is preferable, and 65 to 130 ml is more preferable.

For development processing of the photosensitive material, a method using a solid processing agent is preferred. To solidify the photographic processing agent, a concentrated liquid or a fine or granular photographic processing agent and a water-soluble binder are kneaded and molded, or a water-soluble binder is sprayed on the surface of the temporarily formed photographic processing agent. Any means such as forming a coating layer can be adopted (see JP-A-4-29136 and JP-A-4-29136).
No. 85535, No. 4-85536, No. 4-85533
Nos. 4-85534 and 4-172341).

A preferred tablet production method is a method in which a solid processing agent in the form of powder is granulated and then subjected to a tableting step to form the tablet. Simply mixing the solid processing agent components, the solubility and storage stability are improved over the solid processing agent formed by the tableting process,
As a result, there is an advantage that the photographic performance becomes stable.

Granulation methods for tablet formation include rolling granulation,
Known methods such as extrusion granulation, compression granulation, crushing granulation, stirring granulation, fluidized bed granulation, and spray drying granulation can be used. For tablet formation, the average particle size of the obtained granules is determined by mixing the granules and pressing / compressing them to make the components non-uniform,
100-800 in that so-called segregation hardly occurs.
μm, more preferably 2 μm.
It is 00 to 750 μm. Further, the particle size distribution is preferably such that 60% or more of the granulated product particles have a deviation of ± 100 to 150 μm.

Next, when the obtained granules are pressed and compressed, a known compressor such as a hydraulic press, a single-shot tableting machine, a rotary tableting machine, a briquetting machine and the like are used. Can be used. The solid processing agent obtained by pressurization and compression can take any shape, but productivity,
From the viewpoint of handleability and the problem of dust when used on the user side, a cylindrical type, so-called tablet, is preferred.

More preferably, at the time of granulation, the above-mentioned effect becomes more remarkable by separately granulating each component, for example, an alkali agent, a reducing agent, a preservative, and the like.

A method for producing a tablet processing agent is described in, for example,
Nos. 1-61837, 54-155038 and 52-
No. 88025, British Patent No. 1,213,808, etc. and can be produced by a general method. Granulating agents are described in, for example, JP-A-2-10942, JP-A-2-109043, JP-A-3-39735 and JP-A-3-39735. It can be produced by a general method described in JP-A-3-39739. Powder processing agents are described, for example, in JP-A-54-133332 and British Patent 725,89.
No. 2,729,862 and German Patent 3,733,333.
No. 861, etc., and can be produced by a general method.

The bulk density of the solid processing agent is preferably 1.0 to 2.5 g / cm ³ in the case of a tablet from the viewpoint of solubility and the effect of the object of the present invention. 1.0 g / cm ³
Greater is 2.5% in terms of the strength of the resulting solid.
Less than g / cm ³ is more preferable in terms of solubility of the obtained solid. When the solid processing agent is granules or powder, the bulk density is preferably from 0.40 to 0.95 g / cm ³ .

The automatic developing machine used in the present invention is preferably a known roller-type automatic developing machine. When processing the light-sensitive material of the present invention, it is preferable that the processing is performed in a total processing time (dry to dry) of 10 to 45 seconds using an automatic developing machine, but the processing is performed in a range of 15 to 30 seconds. More preferred. Here, the time from the time when the tip of the photosensitive material to be processed is immersed in the developing tank liquid of the automatic developing machine to the time when it comes into contact with the fixing tank liquid in the next process is referred to as “development time”. "Fixing time" refers to the time until contact with the washing tank solution (stabilizing solution), "Washing time" refers to the time of immersion in the washing tank solution, and "Drying time" refers to the time in the drying zone of the automatic processor. , The developing time is 3 to 15 seconds (further 3 to 10 seconds), the developing temperature is 25 to 50 ° C. (further 30 to 40 ° C.), the fixing time is 2 to 12 seconds (further 2 to 10 seconds).
Sec), fixing temperature 20-50 ° C (further 30-40 ° C),
Water washing (stabilization) time 2 to 15 seconds (further 2 to 8 seconds), water washing (stabilization) temperature 0 to 50 ° C (further 15 to 40 ° C),
Drying time 3-12 seconds (further 3-8 seconds), drying temperature 35
To 100 ° C (more preferably 40 to 80 ° C).

The photosensitive material is developed, fixed and washed (or stabilized), dried with a squeeze roller after squeezing out water.

As an X-ray generator in the image forming method of the present invention, a commercially available X-ray generator can be used. Particularly, as an X-ray generator for mammography, an apparatus having a tube voltage of an X-ray generator tube of 40 kVp or less is commercially available. When the tube voltage of the X-ray generator exceeds 40 kVp, it is difficult to obtain a sufficient contrast.

As a dedicated device for mammography, X
Molybdenum (Mo) is used for the anode of the wire generating tube,
By adding a filter, continuous X-rays of 20 kVp or more that cause a decrease in contrast due to scattering are removed,
Devices that generate X-rays close to a single color including characteristic X-rays have become mainstream. Rhodium (R) is used to obtain contrast in high-density breasts and thick breasts with high X-ray absorption.
An apparatus in which an Rh filter is combined with an h) anode or a tungsten (W) anode is also known. The focal spot size of the anode tends to be miniaturized, and an apparatus having a diameter of 0.1 to 0.3 mm is generally used.

Preferred phosphors used for the X-ray fluorescent intensifying screen include the following. Tungstate phosphors (CaWO ₄ , MgWO ₄ , CaWO ₄ :
Pb etc.), terbium activated rare earth oxysulfide 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, Tm, etc., terbium-activated rare earth phosphate-based phosphor (YPO ₄ : Tb, GdPO ₄ : T)
b, LaPO ₄ : Tb, etc.), terbium-activated rare earth oxyhalide phosphor (LaOBr: Tb, LaOB)
r: Tb. Tm, LaOCl: Tb, LaOCl: T
b. Tm, GdOBr: Tb, GdOCl: Tb),
Thulium-activated rare earth oxyhalide phosphor (La
OBr: Tm, LaOCl: Tm, etc., barium sulfate-based phosphors (BaSO ₄ : Pb, BaSO ₄ : Eu ²⁺ , (B
a. Sr) SO ₄ : Eu ²⁺ etc.) divalent eurobium-activated alkaline earth metal phosphate phosphor (Ba ₃ (P
^{_{O 4) 2: Eu 2 +}} , (Ba.Sr) 3 (PO 4) 2: Eu 2+
Etc.) divalent eurobium-activated alkaline earth metal fluoride halide-based phosphors (BaFCl: Eu ²⁺ , BaFB
r: Eu ²⁺ , BaFCl: Eu ²⁺ . Tb, BaFBr:
Eu ²⁺ . Tb, BaF ₂ . BaCl ₂ . BaSO ₄ . KC
l: Eu ²⁺ , (Ba.Mg) F ₂ . BaCl ₂ . KCl:
Eu ^{2 +} etc.), iodide phosphor (CsI: Na, CsI:
Tl, NaI. KI: Tl, etc.), sulfide-based phosphor (Zn
S: Ag, (Zn. Cd) S: Ag, (Zn. Cd)
S: Cu, (Zn. Cd) S: Cu. Al), a hafnium phosphate-based phosphor (HfP ₂ O ₇ : Cu, etc.). However, the phosphor used in the present invention is not limited to these.

Of these, terbium-activated gadolinium oxysulfide (Gd ₂ O ₂ S: Tb) is particularly preferred as the phosphor.

The average particle diameter of each layer of the phosphor particles constituting each phosphor layer is represented by R, and the particle diameter distribution is represented by σ.
It is preferable that each layer satisfy the relationship of 0 <σ / R ≦ 0.5. Preferably, 0 <σ in each layer
/R≦0.3, more preferably 0 <σ / R ≦ 0.15 in each layer.
Here, the average particle size R indicates the number average, and the particle size distribution σ indicates the standard deviation.

The filling rate of the phosphor in the phosphor layer of the X-ray fluorescent intensifying screen is 68% or more, preferably 70% or more, more preferably 72% or more. As a method of increasing the filling rate, a method of using a thermoplastic elastomer as a binder and performing a compression treatment to reduce the porosity in the phosphor layer is known.

The thickness of the phosphor layer is not less than 135 μm, preferably from 150 to 250 μm.

It is preferable that the X-ray fluorescent intensifying screen is filled with a phosphor in a gradient particle size structure. In particular, it is preferable to coat large-sized phosphor particles on the surface protective layer side, and to coat small-sized phosphor particles on the support side.
2.0 μm, and those having a large particle diameter are preferably in the range of 10 to 30 μm.

The X-ray fluorescent intensifying screen used in the present invention has an X-ray absorption of 45% or more, preferably 50% or more, by increasing the filling rate of the phosphor particles. Incidentally, the X-ray absorption amount is obtained as follows. That is, X-rays generated from a tungsten target operated at 80 kVp from an X-ray generator equivalent to 2.2 mm of aluminum and passed through a 3 mm-thick aluminum plate having a purity of 99% or more are supplied by three-phase power supply. The X-ray fluorescence intensifying screen was fixed at a position 200 cm from the tungsten anode of the target tube, and then measured with an ionizing dosimeter at a position 50 cm after the phosphor layer of the X-ray fluorescence intensifying screen. And
X-ray absorption was determined. As a reference, the X-ray dose at the above measurement position measured without passing through the fluorescent intensifying screen was used.

Preferred binders used in the X-ray fluorescent intensifying screen include thermoplastic elastomers. Specifically, polystyrene, polyolefin, polyurethane,
At least one thermoplastic elastomer selected from the group consisting of polyester, polyamide, polybutadiene, ethylene vinyl acetate, polyvinyl chloride, natural rubber, fluorine rubber, polyisoprene, chlorinated polyethylene, styrene-butadiene rubber and silicone rubber. .

[0159]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited to these embodiments.

Example 1 All the emulsions shown below were prepared in a reaction vessel having a volume of 32 liters. In addition, Asahi Kasei SIP-1013 is used as the ultrafiltration unit, and DAID is used as the circulating pump.
O Rotary Pump was used. The volume of the emulsion circulation portion of the ultrafiltration step was 1.2 liters, and the emulsion was circulated at a constant flow rate of 15 liters / minute. Therefore, the residence time of the reactant solution was 4.8 seconds, and the volume of the emulsion circulation portion in the ultrafiltration step was 3.8% of the volume of the reaction vessel.

The control of the distance between the particles during the particle growth process was performed by appropriately controlling the permeation flux in the ultrafiltration step. Specifically, the flow control valve 1 shown in FIG.
9 so as to maintain the average distance between the particles at the start of the particle growth step 1 over the entire area of the particle growth step 1 and the particle growth step 2 so that the reaction solution in the reaction vessel is ultrafiltered. And concentrated.

(Em1-1 to 1-5: Preparation of Lower Layer Emulsion)
In the following steps, “%” indicates “% by mass” unless otherwise specified.

[Nucleation Step] While maintaining the following gelatin solution B-101 in the reaction vessel at 30 ° C. and stirring at 450 rpm with the mixing and stirring apparatus of FIG. 1, the pH was adjusted with 1N sulfuric acid. Adjusted to 1.96. Thereafter, the S-101 solution and the X-101 solution were added at a flow rate of 5.0 ml / sec by using the double jet method to form nuclei.

(B-101) Low molecular weight gelatin (average molecular weight: 20,000) 32.4 g Potassium bromide 9.92 g Water 12938.0 ml (S-101) Silver nitrate 50.43 g Water 225.9 ml (X-101) Bromide 35.33 g of potassium 224.7 ml of water [Aging step] After the completion of the above addition, the following G-101 solution was added, and the temperature was raised to 60 ° C over 30 minutes. After heating, 60
The stirring was maintained for 20 minutes while maintaining the temperature. Subsequently, the pH was adjusted to 9.5 by adding a 28% aqueous ammonia solution, and the mixture was maintained for 7 minutes. A 1N aqueous nitric acid solution was added thereto to adjust the pH to 5.
Adjusted to 8. During this time, the silver potential of the solution (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) was 1N.
Was controlled to 14 mV by using a potassium bromide solution.

(G-101) Alkali-treated inert gelatin (average molecular weight 100,000) 139.1 g 10% methanol solution of surfactant (AO-1) 4.64 ml water 3266.0 ml AO-1: HO (CH ₂ CH ₂ O) _m [CH (CH ₃ ) CH ₂ O] _19.8 (CH ₂ CH ₂ O) _n H (m + n = 9.77) [Grain growth step 1] After ripening, the double jet method is used. While accelerating the flow rates of the S-102 solution and the X-102 solution (the ratio of the addition flow rate at the end to the addition is about 12 times) 3
Added in 8 minutes. After completion of the addition, add G-102 solution,
After adjusting the stirring rotation speed to 550 rpm, S
The -103 solution and the X-103 solution were added for 40 minutes while accelerating the flow rates (the ratio of the addition flow rates at the end and at the start was about twice). During this time, the silver potential of the solution was controlled at 14 mV using a 1N potassium bromide solution.

(S-102) Silver nitrate 639.8 g Water 2866.2 ml (X-102) Potassium bromide 448.3 g Water 2850.7 ml (G-102) Alkali-treated inert gelatin (average molecular weight 100,000) 203.4 g AO-1 10% methanol solution 6.20 ml water 1867.0 ml (S-103) silver nitrate 989.8 g water 1437.2 ml (X-103) potassium bromide 679.6 g potassium iodide 9.5 g water 1412.0 ml [ Particle Growth Step 2] After the completion of the addition, the temperature of the solution in the reaction vessel was lowered to 40 ° C. over 20 minutes. afterwards,
After adjusting the silver potential in the reaction vessel to −18 mV using a 3.5 N aqueous potassium bromide solution, the S-104 solution and X-1
Solution 04 was added for 7 minutes while accelerating the flow rate (the ratio of the addition flow rate at the end to the start was 1.2 times).

(S-104) Silver nitrate 672.0 g Water 975.8 ml (X-104) Potassium bromide 470.8 g Water 959.4 ml The particle growth step 1 was started over the entire area of the particle growth step 1 and the particle growth step 2. In order to keep the average distance between particles at the time,
The reaction solution in the reaction vessel was circulated to an ultrafiltration device to perform concentration.

After completion of the growth, desalting and washing were carried out according to a conventional method, gelatin was added and the mixture was dispersed well, and the pH was adjusted to 5.8 and the pAg was adjusted to 8.1 at 40 ° C. The resulting emulsion had an average grain thickness of 0.18 μm and an average grain diameter of 1.1.
The particles were hexagonal tabular grains having a size of 3 μm, an average aspect ratio of 6.3, and a coefficient of variation in volume particle size of 0.08. This emulsion was
It was set to -1.

Em1-2 was prepared in the same manner as in Em1-1, except that the metal compound shown in Table 1 was added to the X-104 solution per mole of silver halide in the finished emulsion.
1-5 was obtained. The average particle diameter thickness, average particle diameter, average aspect ratio, and variation coefficient of volume particle diameter were all the same as Em1-1.

(Em2-1 to 2-5: Preparation of Upper Layer Emulsion)
As shown below, Em2-1 was prepared using the same apparatus and method as Em1-1.

[Nucleation Step] While maintaining the following gelatin solution B-201 in the reaction vessel at 30 ° C. and stirring at 450 rpm with the mixing and stirring apparatus of FIG. 1, the pH was adjusted with 1N sulfuric acid. Adjusted to 1.96. Then, the S-201 solution and the X-201 solution were added at a flow rate of 5.0 ml / sec by using the double jet method to form nuclei.

(B-201) Low molecular weight gelatin (average molecular weight: 20,000) 32.4 g Potassium bromide 9.92 g Water 12938.0 ml (S-201) Silver nitrate 50.43 g Water 225.9 ml (X-201) Bromide 35.33 g of potassium 224.7 ml of water [Aging step] After the completion of the above addition, the following G-201 solution was added, and the temperature was raised to 60 ° C over 30 minutes. After heating, 60
The stirring was maintained for 20 minutes while maintaining the temperature. Subsequently, the pH was adjusted to 9.5 by adding a 28% aqueous ammonia solution, and the mixture was maintained for 7 minutes. A 1N aqueous nitric acid solution was added thereto to adjust the pH to 5.
Adjusted to 8. During this time, the silver potential of the solution (measured with a silver ion selective electrode using a saturated silver-silver chloride electrode as a reference electrode) was 1N.
Was controlled to 14 mV by using a potassium bromide solution.

(G-201) Alkali-treated inert gelatin (average molecular weight 100,000) 139.1 g AO-1 10% methanol solution 4.64 ml water 3266.0 ml [Particle growing step 1] After ripening, double While accelerating the flow rates of the S-202 solution and the X-202 solution using the jet method (the ratio of the addition flow rate at the end to the addition at the start is about 12 times) 3.
Added in 8 minutes. After the addition is completed, add G-202 solution,
After adjusting the stirring rotation speed to 550 rpm, S
The -203 liquid and the X-203 liquid were added for 26 minutes while accelerating the flow rates (the ratio of the addition flow rate at the end to the start was about 1.4 times). During this time, the silver potential of the solution was controlled at 19 mV using a 1N potassium bromide solution.

(S-202) Silver nitrate 639.8 g Water 2866.2 ml (X-202) Potassium bromide 448.3 g Water 2850.7 ml (G-202) Alkali-treated inert gelatin (average molecular weight 100,000) 203.4 g AO-1 10% methanol solution 6.20 ml water 1867.0 ml (S-203) silver nitrate 389.8 g water 566 ml (X-203) potassium bromide 267.6 g potassium iodide 5.6 g water 566 ml [particle growth step 2 After the addition was completed, the temperature of the solution in the reaction vessel was lowered to 40 ° C. over 20 minutes. afterwards,
After adjusting the silver potential in the reaction vessel to -18 mV using a 3.5 N aqueous potassium bromide solution, the S-204 solution and X-2
Solution 04 was added for 4.5 minutes while accelerating the flow rate (the ratio of the addition flow rate at the end to the start was 1.1 times).

(S-204) Silver nitrate 308 g Water 447 ml (X-204) Potassium bromide 215.8 g water 439.7 ml Average particles at the start of the particle growth step 1 over the entire area of the particle growth step 1 and the particle growth step 2 So that the distance can be maintained
The reaction solution in the reaction vessel was circulated to an ultrafiltration device to perform concentration.

After completion of the growth, desalting and washing were carried out according to a conventional method, gelatin was added to the mixture, and the mixture was well dispersed. The pH was adjusted to 5.8 and the pAg was adjusted to 8.1 at 40 ° C. The resulting emulsion had an average grain thickness of 0.16 μm and an average grain diameter of 0.9
The particles were hexagonal tabular grains having a size of 2 μm, an average aspect ratio of 5.8 and a coefficient of variation in volume particle size of 0.09. Em2
It was set to -1.

Em2-2 to X-204 were prepared in the same manner as Em2-1, except that the metal compound shown in Table 1 was added per mol of silver halide in the finished emulsion in the amount shown in Table 1.
2-5 was obtained. The average particle thickness, the average particle diameter, the average aspect, and the coefficient of variation of the volume particle diameter were all the same as Em2-1.

(Chemical sensitization and spectral sensitization)
10 minutes after heating m1-1 to 1-5 and Em2-1 to 2-5 to 60 ° C. and adding a predetermined amount of the spectral sensitizing dyes SD-1 and SD-2 as a dispersion of solid fine particles. , Adenine,
A mixed aqueous solution of ammonium thiocyanate, chloroauric acid and sodium thiosulfate and a dispersion liquid of sensitizer Se-1 were added, and after 30 minutes, silver iodide fine particles were added, followed by ripening for a total of 2 hours. At the end of aging, a predetermined amount of stabilizer ST-1 was added.

The amounts added per mole of silver halide are shown below. SD-1 300 mg SD-2 30 mg Adenine 10 mg Ammonium thiocyanate 90 mg Chloroauric acid 20 mg Sodium thiosulfate 2.0 mg Se-1 0.2 mg Silver iodide fine particles 0.3 mmol ST-1 500 mg Gelatin 40 g SD-1: 5 5-Dichloro-9-ethyl-3,3'-di- (3-sulfopropyl) oxacarbocyanine sodium salt anhydride SD-2: 5,5-di- (butoxycarbonyl) -1,1'-diethyl -3,3'-di- (4-sulfobutyl) benzimidazolocarbocyanine sodium salt anhydride Se-1: triphenylphosphine selenide ST-1: 4-hydroxy-6-methyl-1,3,3a, 7-Tetrazaindene The solid particulate dispersion of the above spectral sensitizing dye was prepared by a known method. That is, the predetermined amount of the spectral sensitizing dye is
High-speed stirrer (dissolver) in addition to water controlled at 7 ° C
At 3,500 rpm for 30 to 120 minutes.

The dispersion of the selenium sensitizer was prepared as follows. That is, 120 g of Se-1 was added to 30 kg of ethyl acetate at 50 ° C., and completely dissolved by stirring. On the other hand, 3.8 kg of photographic gelatin was dissolved in 38 kg of pure water, and to this was added 93 g of a 25% aqueous solution of sodium dodecylbenzenesulfonate. Next, these two liquids were mixed, and a high-speed stirring type disperser having a dissolver having a diameter of 10 cm was used.
Per second for 30 minutes. Thereafter, ethyl acetate was removed while rapidly stirring under reduced pressure until the residual concentration of ethyl acetate became 0.3% or less. Thereafter, this dispersion was diluted with pure water to finish up to 80 kg. A part of the dispersion thus obtained was fractionated and used.

(Preparation of Emulsion Layer Coating Solution) The following various additives were added per mol of silver halide to each of the emulsions obtained above.

1,1-Dimethylol-1-bromo-1-nitromethane 7 mg t-butyl-catechol 130 mg polyvinylpyrrolidone (molecular weight 10,000) 1.0 g sodium polystyrenesulfonate 2.0 g trimethylolpropane 7.0 g nitrophenyl- Triphenyl-phosphonium chloride 20 mg Sodium 1,3-dihydroxybenzene-4-sulfonate 400 mg 2-Sodium 2-mercaptobenzimidazole-5-sulfonate 10 mg C ₄ H ₉ OCH ₂ CH (OH) CH ₂ N (CH ₂ COOH) ₂ 650 mg (Preparation of coating solution for protective layer on emulsion layer side) (per 1 m ² ) Gelatin 0.9 g Polymer particles (described in Tables 2 to 5) 30 mg Hardener H-1 Added so that the swelling ratio becomes 150%. Adjust the amount Compound S-1 7m g Compound S-2 40 mg Compound S-3 5 mg Backing layer (Preparation of antihalation dye layer solution) (per 1 m ² ) Gelatin 2.1 g Dye D-1 35 mg Dye D-2 35 mg Dye D-3 35 mg (Protective layer coating) Preparation of liquid) (per 1 m ² ) Gelatin 0.9 g Matting agent (PMMA with an average particle size of 5 μm) 100 mg Compound S-1 7 mg Compound S-2 50 mg Compound S-3 6 mg Hardener H-1 Swelling ratio is 150% H-1: (CH ₂ ＣＨCHSO ₂ CH ₂ CONHCH ₂ —) ₂ S-1: Dihexyl sulfosuccinate sodium salt S-2: C ₁₁ H ₂₃ CON [(CH ₂ CH ₂ O) _m H] _{(CH 2 CH 2 O) n} H where m + n = 10 S-3 : C 8 F 17 SO 2 n (C 3 H 7) (CH 2 CH 2 O) 15 H PMMA: Po Methyl methacrylate

[0183]

Embedded image

(Coating of photosensitive material) By using these coating solutions, a silver amount of 1.5 g / m 2 was coated on one surface of the support.
² , 1.5 g / m ^{2 of} emulsion lower layer, emulsion protective layer gelatin amount of 0.1 g / m ² .
Glycidyl methacrylate using two slide hopper type coaters so that the amount of the antihalation dye layer, the intermediate layer and the protective layer on the other surface was 9 g / m ^2, and the amount of gelatin was as shown in Table 1. / Methyl acrylate /
A 175 μm-thick blue-colored PET coated and dried with a copolymer dispersion obtained by diluting a butyl methacrylate (50/10/40 mass ratio) copolymer so as to have a concentration of 10%, and drying it. Coating was performed simultaneously on both sides of the support at a speed of 120 m / min, and drying was performed for 2 minutes and 20 seconds to prepare a photosensitive material sample.

A sample was prepared by coating a sample having only the upper layer of the emulsion and a sample having only the lower layer of the emulsion in the same manner. Table 1 shows the results obtained by using the sample of the upper emulsion alone and the sample of the lower emulsion alone to determine the difference in sensitivity between the two emulsions by the following sensitometry method. In the case of the combination of the lower emulsion and the upper emulsion, Δlog =
It was 0.18-0.19.

[0186]

[Table 1]

<Preparation of solid developer> [Granulated product (A)] 1050 g of sodium metabisulfite,
450 g of 1-phenyl-3-pyrazolidone, 7200 g of sodium erysorbate monohydrate, 810 g of binder D-sorbit, 7 g of N-acetyl-DL-penicillamine,
300 g of glutaraldehyde bisulfite adduct is mixed at room temperature for about 3 minutes in a commercially available stirring granulator, and granulated by adding 150 ml of water over 1 minute, and then drying the granulated product by fluidized bed drying. The granules are dried at 50 ° C. for 2 hours to remove the moisture of the granules almost completely.

[Granulated product (B)] Potassium carbonate 9500
g and 6.0 g of potassium iodide are each ground in a commercially available bantam mill to an average of 10 μm. These fine powders and DTPA-Na (diethylenetriaminepentaacetic acid / 5
Sodium salt) 170 g, sodium sulfite 425 g,
5-mercapto- (1H) -tetrazolylacetic acid sodium salt 8.3 g, 1- (3-sulfophenyl) -5-mercaptotetrazole sodium salt 40 g, 5-nitroindazole 3.0 g, binder mannitol 1500 g,
600 g of D-Sorbit was added, mixed at room temperature for about 3 minutes in a commercially available stirring granulator, and granulated by adding 125 ml of water over 1 minute. After drying at 2 ° C. for 2 hours, the water content of the granules is almost completely removed.

The granulated product (A) thus obtained was added with 1
1.0% of the total mass of sodium octanesulfonate,
Methyl-β-cyclodextrin was added at 3% of the total mass, 25%.
C., and added and mixed in a room conditioned at 40% RH or less. Further, the granulated product (B) contains sodium 1-octanesulfonate at 1.2% of the total mass and methyl-β-cyclodextrin at the total mass. In a room conditioned at 25 ° C. and 40% RH or less, and mixed with Kikusui Seisakusho's Tough Press Collect 1
527HU was subjected to compression tableting using a modified tableting machine to produce each of the developed tablets (A) and (B). The filling amount per tablet was (A) 8.45 g and (B) 12.4 g. (A) 60 pieces, (B) 50 pieces (volume after dissolution is 5.
The tablets were sealed and packaged using a packaging material having the following layer structure for moisture prevention.

The packaging material is biaxially stretched nylon (ONY)
15 μm thickness / aluminum oxide deposited PET 12 μm thickness /
A bag made of a laminate material consisting of biaxially oriented polypropylene (OPP) 25 μm thick / low-density polyethylene (LLDP) 40 μm thick, and the effective surface area on the side (inside) of the packaging material in contact with the tablets was 1300 cm ² . .

<Preparation of Solid Fixing Agent> [Granulated Material (C)] In a commercially available bantam mill, 14580 g of ammonium thiosulfate / sodium thiosulfate (90/10 mass ratio) is pulverized to an average of 10 μm. The compound (HOCH ₂ CH ₂ SCH ₂ CH ₂ SCH ₂ CH _{2) is} added to the fine powder.
OH) 1000 g, sodium metabisulfite 920 g,
After adding 50 g of 5-mercapto-1H-tetrazole and 900 g of binder pine flow, mixing at room temperature for about 3 minutes in a commercially available stirring granulator, and granulating by adding 150 ml of water over 1 minute. The granules are dried at 40 ° C. in a fluidized bed drier to remove water almost completely.

[Granulated product (D)] 250 g of boric acid, 1500 g of aluminum sulfate octahydrate, 1150 g of succinic acid, 250 g of tartaric acid, 208 g of mannitol, 10 g of D-sorbitol
After mixing 0 g in a commercially available stirring granulator at room temperature for about 3 minutes and adding 150 ml of water over 1 minute to granulate, the granulated material is dried at 40 ° C. in a fluidized bed drier. To remove water almost completely.

The granulated product (C) thus obtained, 1400 g of sodium acetate and sodium 1-hexanesulfonate in a room conditioned at 2.5% of the total mass at 25 ° C. and 40% RH or less. 1400 g of sodium acetate was added to the granulated product (D), and sodium 1-hexanesulfonate was further added to 3.0% of the total mass at 25 ° C./40%.
The mixture was added and mixed in a room humidified to RH or lower, and compressed and compressed using a tableting machine (described above) in which Tough Press Collect 1527HU was modified to produce fixing tablets (C) and (D). The filling amount per tablet is (C) 10.5 g, (D)
8.95 g. Using the packaging materials used for developing tablets (A) and (B) for moisture proof, 92 (C) and 28 (D) (the volume after dissolution becomes 5.0 liters) were used for moisture proofing. The tablets were sealed and packaged.

<Formulation of development starter (addition amount per liter of developer)> N-acetyl-DL-penicillamine 0.11 g Diethylene glycol 48.5 g 5-mercapto- (1H) -sodium tetrazolyl acetate 0.12 g 90% acetic acid 11. 5 g Potassium bromide 8.0 g Finished to 67 ml with pure water (Developer) TCX-701 (manufactured by Konica) was used as an automatic developing machine. At the start, 7.8 liters of the developing solution in which the developing tablet was dissolved was added to the developing solution in the developing tank, and a starter was added to fill the developing tank as a starting solution to start processing. The starter was added in an amount of 67 ml / liter of the developing solution, and an amount corresponding to the developing tank capacity of 7.8 liter was added. Similarly, 5.6 liters of the prepared fixing solution was placed in a fixing processing tank of TCX-701 to be used as a starting solution.

In each of the developing and fixing steps, each of the packaging bags was opened by hand at the inlet of each solid agent, and then set.
Drop tablets into the built-in chemical mixer and add hot water (2
5-30 ° C.) and dissolve with stirring for 25 minutes.
Make up to 5.0 liters per minute. This was used as a developing and fixing replenisher.

The pH when the developer was dissolved was 10.15,
The pH when the starter was added was 9.90. The dissolution pH of the fixing solution was 4.25.

The built-in chemical mixer is divided into a liquid preparation tank and a spare tank tank. The capacity of the liquid preparation tank is 5.0 liters and the capacity of the spare tank is 5.0 liters. A spare tank is provided to supply the replenisher so that the replenisher does not enter the non-replenished state during the stirring and dissolving time (about 25 minutes) even if the replenisher produced runs out.

Development temperature 34 ° C. (replenishment rate is 100 ml / m
² ), fixing temperature 34 ° C. (replenishment amount is 100 ml / m ² ), water washing temperature 18 ° C. (5 l / min), drying temperature 55 ° C.
And the processing time was 45 seconds.

(Evaluation of Sensitometry) Using the obtained sample, the emulsion surface was subjected to mammography X-ray fluorescent intensifying screen M-
100 (made by Konica Corporation) was closely adhered to the phosphor layer surface in the cassette. X-ray irradiation was performed after standing for 10 minutes in order to keep the adhesion high and constant. The X-ray generator was ROTANODE manufactured by Toshiba Corporation, and irradiation was performed at a tube voltage of 27 kVp and a tube current of 100 mA (focal size: 0.4 mm) for 0.5 seconds. At this time, an acrylic plate with a thickness of 2 cm
cm.

After the development, a sensitometry curve was prepared by the distance method, and the sensitivity and gradation were determined. The sensitivity value was determined as the reciprocal of the X-ray dose required to obtain a density of fog + 1.0, and the relative sensitivity was evaluated with the value of the film of Sample 1 as 100. The gradation is plotted with the logarithm of the X-ray exposure on the horizontal axis and the optical density on the vertical axis.
Where the angle between the straight line connecting the points and the horizontal axis is θ
It was represented by nθ.

The scratch resistance and fingerprint resistance were also evaluated according to the following criteria. << Abrasion resistance >> Unexposed sample film was heated at 23 ° C
(Relative humidity) After leaving it for 2 hours under the condition of 40%, rubbing it with a commercially available nylon scourer under the same conditions under a load of 100 g / cm ² , then processing with an automatic developing machine under the above conditions, Visual evaluation was performed.

A: Almost no scratch B: Level of practically no problem, but slight scratch C: Scratch occurs to the extent of being noticeable and is a problem in practical use D: Very large scratch, width of scratch Thick and dense << Fingerprint resistance >> Under the condition kept at room temperature 23 ° C. and RH 50%, the unexposed sample film is gently pressed with a finger for 3 seconds, and the density is about 1. Exposure and development processing was performed so as to be 0. The obtained sample was visually evaluated according to the following four grades.

A: Almost no fingerprint mark B: Slight fingerprint mark when viewed closely C: Fingerprint mark is generated to the extent that it is conspicuous D: Fingerprint mark is very strong, which is a problem in practice << Diagnostic Ability> Using the obtained sample, KYOKKO15 was placed in a cassette in which the sample was placed using the same device as used for sensitometry evaluation.
A 6-mamma phantom (manufactured by Kasei Optonics Co., Ltd.) was closely attached and photographed, and a tumor image, a microcalcification image, and a fiber image were visually evaluated.

A: All are clearly visible B: All are sufficiently visible C: Some images are hard to see D: All images are hard to see The results are also shown in Tables 2 to 5.

[0205]

[Table 2]

[0206]

[Table 3]

[0207]

[Table 4]

[0208]

[Table 5]

The samples of the present invention were excellent in any of the evaluations.

[0210]

Industrial Applicability According to the present invention, a silver halide photographic material for X-ray mammography having high contrast, excellent diagnostic performance, and excellent scratch resistance and fingerprint mark resistance, a method for processing the same, and a method using the same are provided. An X-ray image forming method can be provided.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of a silver halide emulsion manufacturing apparatus applicable to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reaction container 2 Stirring mechanism 3 Dispersion medium 4 Silver addition line 5 Halide addition line 6 Dispersion medium addition line 7 Addition line 8 Liquid take-out line 9 Liquid return line 10 Permeate discharge line 11 Permeate return line 12 Ultrafiltration unit 13 Circulation Pump 14 Flow meter 15, 16, 17 Pressure gauge 18 Pressure adjusting valve 19 Flow adjusting valve 20 Silver addition valve 21 Halide addition valve 22 Liquid extraction valve 23, 24, 25 Valve 26 Ultrafiltration permeate 27 Permeate receiver 28 Scale 29,30 Silver halide fine particle addition line 31,32 Fine particle addition valve

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) G03C 1/76 501 G03C 1/76 501 5/17 5/17 5/26 520 5/26 520 5/305 5/305

Claims (18)

[Claims] 1. A support having at least one light-sensitive silver halide emulsion layer on one surface and a non-light-sensitive colloid layer above the light-sensitive silver halide emulsion layer. In a silver halide photographic light-sensitive material having a backing layer, the relative standard deviation of the particle size in the non-light-sensitive colloid layer is 1
0% or less of spherical polymer particles, wherein at least one of the photosensitive silver halide emulsion layers has at least one metal selected from rhodium, ruthenium, rhenium, and osmium at least 50% of the total projected area. A silver halide photographic material comprising ion-doped tabular silver halide grains having an aspect ratio of 3 to 30. 2. A support having at least one light-sensitive silver halide emulsion layer on one surface and a non-light-sensitive colloid layer above the light-sensitive silver halide emulsion layer. In a silver halide photographic material having a backing layer, the non-photosensitive colloid layer has polymer particles containing 5 to 15 mol% of an acidic monomer, and at least one of the photosensitive silver halide emulsion layers has A silver halide photographic light-sensitive material wherein at least 50% of the projected area is tabular silver halide grains having an aspect ratio of 3 to 30 doped with at least one metal ion selected from rhodium, ruthenium, rhenium and osmium. material. 3. A support having at least one light-sensitive silver halide emulsion layer on one surface and a non-light-sensitive colloid layer above the light-sensitive silver halide emulsion layer. A silver halide photographic material having a backing layer, wherein the non-photosensitive colloid layer contains polymer particles obtained by copolymerizing a nonionic ethylenically unsaturated monomer and an ethylenically unsaturated monomer other than anionic. Silver halide emulsion layer, at least one layer of which is at least 50% of the total projected area is doped with at least one metal ion selected from rhodium, ruthenium, rhenium, and osmium, and has an aspect ratio of 3 to 30 and is tabular silver halide. A silver halide photographic light-sensitive material characterized by being grains. 4. The polymer particles according to the following general formula (M)
The nonionic ethylenically unsaturated monomer represented by
4. The silver halide photographic light-sensitive material according to claim 3, wherein the silver halide photographic light-sensitive material is obtained by copolymerizing the silver halide photographic material. Embedded image [In the formula, R represents a hydrogen atom or a methyl group, and A represents a divalent group. ] 5. The silver halide photographic material according to claim 4, wherein A in the general formula (M) is the following structural formula. A: (—OCH ₂ CH ₂ —) _n1 or [—OCH ₂ CH (C
H ₃₎ -] _n2 or _{-OCH 2 CH (OH) CH 2} - [wherein, n1 is 1
And n2 represents an integer of 1 to 12. ] 6. The metal ion doping amount selected from rhodium, ruthenium, rhenium and osmium is 1 × 10 ^−10.
The silver halide photographic light-sensitive material according to any one of claims 1 to 5, wherein the content is from 1 to 10 ^-7 mol / mol AgX. 7. A tabular halide obtained by growing a silver halide grain contained in a silver halide emulsion layer by ultrafiltration while appropriately extracting a solution containing a salt from a reaction solution during the growth process. The silver halide photographic material according to any one of claims 1 to 6, wherein the material is silver halide grains. 8. The silver halide photographic material according to claim 7, wherein the tabular silver halide grains have a coefficient of variation of a volume particle size of 0.10 or less. 9. The silver halide photographic light-sensitive material according to claim 1, which is substantially free of hydroquinones and contains a compound represented by the following formula (I) and nitroindazole. A method for processing a silver halide photographic light-sensitive material, wherein the processing is performed with a developer containing the bromine ion concentration of 10 g / liter or more in terms of potassium bromide. Embedded image [R ₁ and R ₂ each represent a hydroxyl group, a mercapto group,
Represents a substituted or unsubstituted amino group, acylamino group, alkylsulfonylamino group, arylsulfonylamino group, alkoxycarbonyl group or alkylthio group. Z represents an atomic group necessary for forming a substituted or unsubstituted 5- or 6-membered ring. ] 10. The method for processing a silver halide photographic material according to claim 9, wherein the developer is a solution in which a solid developer is dissolved. 11. The method for processing a silver halide photographic material according to claim 10, wherein the solid developer is a tablet. 12. The surface of a silver halide photographic light-sensitive material according to any one of claims 1 to 8, wherein a surface of the X-ray fluorescent intensifying screen having a phosphor layer is adhered to a surface of the silver halide emulsion layer having the silver halide emulsion layer. ,
An image forming method comprising forming an X-ray image by irradiating X-rays transmitted through a subject, followed by developing, fixing, washing and drying with an automatic developing machine. 13. The image forming method according to claim 12, wherein the phosphor of the X-ray fluorescent intensifying screen is terbium-activated gadolinium oxysulfide. 14. An image forming method according to claim 12, wherein the processing method according to claim 9, 10 or 11 is used. 15. The image forming method according to claim 12, wherein the X-ray has a tube voltage of 40 kVp or less. 16. The silver halide photographic material according to claim 1, which is used for X-ray mammography. 17. The method for processing a silver halide photographic light-sensitive material according to claim 9, which is for X-ray mammography. 18. The image forming method according to claim 12, wherein the method is for X-ray mammography.