JPH0784343A - Assembly of silver halide photographic material and radiation intensifying screen, and silver halide photographic material processing method - Google Patents

Abstract

PURPOSE:To provide a new X-ray photographing method obtaining an excellent image in the balance of graininess and sensitivity. CONSTITUTION:A radiation image forming assembly is formed of silver halide photosensitive material having photosensitive emulsion layers on both sides of base material, and two radiation intensifying screens disposed respectively in front and in the rear of the photosensitive material. In this assembly, at least one of the radiation intensifying screens is a radiation intensifying screen showing absorption quantity of 25% or more to an X-ray of 80kVp in X-ray energy, and the quantity of silver contained in the silver halide photographic material is 2.5g/m<2> or less at the sum of both sides of the base material.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel silver halide photographic light-sensitive material and a novel X-ray image forming method. Furthermore, the present invention relates to a development processing method which is preferable from the viewpoints of toxicity and safety in developing the silver halide photographic light-sensitive material of the present invention with less environmental load.

[0002]

2. Description of the Related Art In medical radiography, an image of a patient's tissue is obtained by using a photographic light-sensitive material (silver halide photographic light-sensitive material) containing at least one light-sensitive silver halide emulsion layer coated on a transparent support. It is used by recording an X-ray transmission pattern on the silver halide photographic light-sensitive material. The X-ray transmission pattern can be recorded by using the silver halide photographic light-sensitive material alone. However, since it is not desirable for the human body to be exposed to a large amount of X-ray exposure, X-ray photography is usually carried out by combining a radiation intensifying screen with a silver halide photographic light-sensitive material. The radiographic intensifying screen is provided with a phosphor layer on the surface of a support, and the phosphor layer absorbs X-rays,
In order to convert visible light, which has high photosensitivity for photosensitive materials,
Its use can significantly improve the sensitivity of the X-ray imaging system.

As a method for further improving the sensitivity of an X-ray photography system, a light-sensitive material having photographic emulsion layers on both sides, that is, a silver halide photographic having silver halide photographic light-sensitive layers on the front side and the back side of a support, respectively. A method has been developed in which a photosensitive material is used, and both sides of it are sandwiched by a radiation intensifying screen (sometimes referred to simply as an intensifying screen). Various shooting methods are used. This method is a method developed because a sufficient amount of X-ray absorption cannot be achieved by using a single intensifying screen. That is, even if the phosphor amount of one intensifying screen is increased to increase the X-ray absorption amount, the visible light converted in the phosphor layer thickened due to the increase is scattered inside the phosphor layer. Since the light is reflected, the visible light emitted from the intensifying screen and incident on the photosensitive material arranged in contact with the intensifying screen is greatly blurred. Further, since visible light generated in the deep part of the phosphor layer is hard to be emitted from the phosphor layer, even if the phosphor layer is unnecessarily increased, effective visible light emitted from the intensifying screen does not increase. Therefore, the X-ray photography method using two intensifying screens having a phosphor layer of a suitable thickness increases the X-ray absorption amount as a whole, and the visible light effectively converted from the intensifying screen. Has the advantage that it can be taken out. Research to find an X-ray imaging system that is excellent in the balance between image quality and sensitivity has been continuously conducted until now. For example, conventionally, a combination of a blue emission intensifying screen having a phosphor layer of a calcium tungstate phosphor and a silver halide photographic light-sensitive material which has not been spectrally sensitized (eg, high screen standard and RX (both Fuji Photo Film Co., Ltd. product name)
Was used commonly, but recently,
A combination of a green light-emitting intensifying screen having a phosphor layer of a terbium-activated rare earth element oxysulfide phosphor and an ortho-spectral-sensitized silver halide photographic light-sensitive material (eg, HR-4 and SuperHR-S (both are The combination with Fuji Photo Film Co., Ltd.) has come to be used, and improved results have been obtained in both sensitivity and image quality.

Incidentally, in a silver halide photographic light-sensitive material having photographic emulsion layers on both sides, there is a problem that deterioration of image quality easily occurs due to crossover light. The crossover light is emitted from the respective intensifying screens arranged on both sides of the photosensitive material, passes through the support of the photosensitive material (usually a thick one of about 170 to 180 μm is used), and is exposed on the opposite side. Visible light that reaches a layer, and is light that causes deterioration of image quality (particularly sharpness).

Various techniques have been developed to reduce the crossover light. For example, there is an invention using a spectrally sensitized high aspect ratio tabular grain emulsion disclosed in U.S. Pat. Nos. 4,425,425 and 4,425,426 as a light-sensitive silver halide photographic emulsion, and U.S. Pat. No. 4,803,150. The specification discloses an invention in which a microcrystalline dye layer capable of being decolorized by a developing process is provided between a support of a silver halide photographic light-sensitive material and a light-sensitive layer.

On the other hand, a combination of a silver halide photographic light-sensitive material having photographic emulsion layers on both sides and a radiation intensifying screen is set under specific conditions to find an X-ray photographing system excellent in the balance of image quality and sensitivity. Attempts have also been made to get out. For example, JP-A-2-266344 and 2-
297544 and US Pat. No. 4,803,150.
In the specification, the optical characteristics (sensitivity) obtained by the combination of the intensifying screen (front intensifying screen) on the X-ray irradiation side and the photosensitive layer (front photosensitive layer) are described as follows. The light characteristics (sensitivity) obtained by the combination of the sensitive screen) and the photosensitive layer (rear surface photosensitive layer) are set to be different from each other, and the former combination and the latter combination have different contrasts. A set X-ray imaging system is disclosed. Meanwhile, Photographic Science and Engineering, Vol. 26, No. 1
No. 40 (No. 1982), in the combination of a radiation intensifying screen manufactured by 3M and a silver halide photographic material, Trimax 12 (trade name of commercially available intensifying screen of 3M) and XUD (commercial halogen of 3M). The combination with the trade name of the silver halide photographic light sensitive material is Trimax 4 (the trade name of the commercial intensifying screen of 3M) and XD (the trade name of the commercial silver halide photographic material of 3M).
The sensitivity and sharpness (MT
F) is shown, but shows the experimental results that give a high NEQ (output signal to noise ratio). And
This result shows that XUD has higher sharpness than XD,
On the other hand, it teaches that Trimax 12 exhibits a higher X-ray absorption amount than Trimax 4.

Of course, if attention is paid only to the image quality of the X-ray image,
It was possible to obtain a high-quality X-ray image by using a low sensitivity silver halide photographic light-sensitive material in combination with a similarly low-sensitivity radiation intensifying screen. However, when such a combination of low sensitivities is used, the exposure dose (exposure dose) of X-rays to the human body is inevitably increased. When most of the subjects are healthy people, it is necessary to avoid increasing the dose as much as possible.
You can't actually use it.

On the other hand, in recent years, problems of increasing environmental load and pollution have come to the surface in various fields. Attention is paid to the development / fixing waste liquid treatment in the development processing of silver halide photographic light-sensitive materials and the waste water of washing water from this viewpoint, and recycling after fixing and water saving technology for washing water have already been put to practical use. There is. Commonly used black and white silver halide sensitizer (X
(For ray, plate making, micro, negative, etc.), hydroquinone has been used as a developing agent, and an auxiliary developing agent has been used 3-
After being developed with an alkaline developer containing a pyrazolidone compound or an aminophenol compound, an image is formed by a development process including fixing and washing (stabilizing) steps.

Among them, since the X-ray photographic light-sensitive material is processed by a rapid automatic developing machine having a short developing time, a highly active developing solution containing a large amount of hydroquinone as a developing agent is used. In order to maintain high activity from such a developing solution, it has been replenished in a large amount against air oxidation. However, the toxicity and safety of hydroquinone is now becoming a problem. Sulfite, which is used to prevent the oxidation of hydroquinone, is a source of a silver halide salt dissolved in a developing solution, which is reduced in the developing solution to cause so-called silver stain. Therefore, alternatives have become necessary. One of them is US Pat.
These are reductones known from JP-A-8-549 and JP-A-3-249756. However, since reductones have lower developing activity and inferior developing progress as compared with hydroquinone, it was difficult to put them into practical use as a rapid processing developer for X ray.

On the other hand, ammonium thiosulfate is used in the fixing solution of the X-ray photographic light-sensitive material in order to achieve rapid automatic development processing. Sodium thiosulfate from which ammonia has been removed in terms of odor and environmental load is used. Is desired to be used. However, with a fixing solution using sodium thiosulfate, there is a problem that the X-ray photographic light-sensitive material up to that point cannot be processed unless the fixing time is extended, and both rapid processing and environmental problems cannot be satisfied. .

[0011]

The object of the present invention is, first of all, that a new combination of a radiation intensifying screen and a silver halide photographic light-sensitive material provides an excellent image quality, especially in balance of graininess and sensitivity. It is to provide a new radiographic method for obtaining an image. The second is to provide a means for reducing the amount of developing / fixing replenisher in order to reduce the load on the environment and for realizing the rapid automatic processor processing of the X-ray sensitive material. Thirdly, from the viewpoint of safety, hydroquinone is not used as a developing agent, and instead of reductones, a sensitive material / processing system is provided as a rapid automatic processor processing for X-ray sensitive material. Is to do.

[0012]

The above object of the present invention has been achieved by the following method. First, there is provided a radiographic image forming assembly comprising a silver halide photographic light-sensitive material having a light-sensitive emulsion layer on both sides of a support, and two radiographic intensifying screens arranged before and after the light-sensitive material. use,
The conditions (1) and (2) below were satisfied. (1) At least one of the radiographic intensifying screens is a radiographic intensifying screen showing an absorption amount of 25% or more for X-rays having an X-ray energy of 80 KVp. (2) A radiation image forming assembly characterized in that the total amount of silver contained in the silver halide photographic material is 2.5 g / m ² or less on both sides of the support.

Secondly, a silver halide photographic light-sensitive material characterized in that the amount of silver contained in the silver halide photographic material is 2.5 g / m ² or less in total on both sides of the support, In the method of processing with an automatic processor while replenishing a developing solution and a fixing solution, it was decided to develop a silver halide photographic light-sensitive material so that the following relations would be satisfied. Sd ≦ 15, Sf ≦ 15, T ≦ 150 where Sd is the replenishing amount of developing solution per 775 cm ^{2 of the} photosensitive material (ml), Sf is the replenishing amount of fixing solution per 775 cm ^{2 of the} photosensitive material (ml), T represents the time (seconds) from the time when the tip of the photosensitive material is inserted into the automatic processor to the time when the tip passes through the drying zone and comes out. Further, in this automatic development processing method, the silver halide photographic light-sensitive material was treated with an X-ray energy of 25 at 25 KVp.
The effect of the present invention was preferably achieved by exposing the film in combination with a radiation intensifying screen showing an absorption amount of not less than%, and then performing development processing. Furthermore, in the method of automatically developing the silver halide photographic light-sensitive material, the processing is performed by using the reductone represented by the general formula (1) as a developing agent in the developer, thereby improving safety. I got it. General formula (1)

[0014]

[Chemical 2]

Here, R is a hydrogen atom or a hydroxyl group,
n is an integer of 1 to 4.

Further, regarding the radiation intensifying screen for exposing the silver halide photographic light-sensitive material, at least one of them has an X-ray energy of 25% with respect to X-rays of 80 KVp.
Shows the above absorption amount and contrast transfer function (CTF)
However, at a spatial frequency of 1 line / mm, 0.79 or more, a spatial frequency of 3
After exposure with an assembly having a number of lines / mm of 0.36 or more, the development processing of the present invention was performed. Furthermore, the effect of the present invention is further enhanced by performing the exposure and automatic development processing of the present invention with the halogen composition of the silver halide grains of the silver halide photographic light-sensitive material set to a silver chloride content of 20 mol% or more. Notably realized.

According to the research conducted by the present inventor, in the combination of the silver halide photographic light-sensitive material and the radiation intensifying screen, the optimum distribution of the intensifying screen and the light-sensitive material is determined by the sensitivity level of the combination and the size of the subject. It has been found that it will change depending on factors such as the size. However, it is completed by the assembly,
Each diagnostic image has a preferred acceptable sharpness level, which is the CTF value at relatively low spatial frequencies:
That is, it was found that it can be represented by the CTF value at a spatial frequency of 1 line / mm. Higher CTF value than spatial frequency 1 line / mm is desirable, but CTF value with spatial frequency 1 line / mm is higher than that, and image graininess is smooth. Was found to be superior in diagnostic ability. Here,
This preferable and acceptable sharpness level is 0.65 at 1 line / mm in clinical evaluation in the chest.
As mentioned above, it was 0.22 or more at 2 lines / mm.

The sensitivity of the light-sensitive material and the sensitivity of the intensifying screen can be arbitrarily combined, but there is a preferable composition of the assembly. If the sensitivity of the assembly is constant and the X-ray absorption amount is very large and a high-sensitivity intensifying screen and a low-sensitivity light-sensitive material are used in combination, the granularity of the obtained image is extremely good. However, the sharpness is remarkably reduced. In this case, even if a light-sensitive material having low sensitivity and high sharpness is used as the light-sensitive material, the sharpness of the obtained image will not be sufficient, and a diagnostically preferable X-ray image will not be obtained. vice versa,
When a low-sensitivity intensifying screen with a small amount of X-ray absorption is used in combination with a standard or high-sensitivity light-sensitive material, an X-ray image with high sharpness can be obtained, but the granularity deteriorates. The X-ray image is not favorable for diagnosis. The best combination has an X-ray absorption of 25% or more for 80 KVp X-rays and a CTF of 0.79 (1 line / mm).
And a relatively high intensifying screen of 0.36 (3 lines / mm) or more, and a photosensitive material in which the sensitivity of the photosensitive material is lowered by the amount of canceling the high sensitivity characteristics of the intensifying screen. Is Rukoto.

The preferable specific sensitivity range of the silver halide photographic material is as follows, which has the same wavelength as the main emission peak wavelength of the radiation intensifying screen and is exposed with monochromatic light having a half width of 20 ± 5 nm. Using developer [I], developer temperature 3
Development is carried out at 5 ° C. for 25 seconds for development, the photosensitive layer on the side opposite to the exposed surface is peeled off, and then measured, and the density obtained in the photosensitive layer is a value obtained by adding 0.5 to the minimum density. The exposure amount required for the exposure has a sensitivity of 0.010 lux seconds to 0.035 lux seconds (preferably 0.012 to 0.030 lux).

Developer [I] potassium hydroxide 21 g potassium sulfite 63 g boric acid 10 g hydroquinone 25 g triethylene glycol 20 g 5-nitroindazole 0.2 g glacial acetic acid 10 g 1-phenyl-pyrazolidone 1.2 g 5-methylbenzotriazole 0.05 g Glutaraldehyde 5g Potassium bromide 4g Add water to make 1 liter and adjust to pH 10.20

The sensitivity in this range is set lower than that of a commercially available X-ray film, for example, X-ray film Super HRS manufactured by Fuji Photo Film Co., Ltd.
In the method for measuring the sensitivity of a silver halide photographic light-sensitive material, the exposure light source used must match or almost match the wavelength of the emission main peak of the radiation intensifying screen used in combination. For example, when the phosphor of the radiation intensifying screen is terbium-activated gadolinium oxysulfide, the peak wavelength of the main emission is 545 nm, so the light source for measuring the sensitivity of the silver halide photographic light-sensitive material has a wavelength of 545 nm. The light is centered around. As a method for obtaining monochromatic light, a method using a filter system combined with an interference filter can be used. According to this method, although it depends on the combination of interference filters, it is usually possible to easily obtain monochromatic light having a necessary exposure amount and a half width of 20 ± 5 nm. It should be noted that the silver halide photographic light-sensitive material has a continuous spectral sensitivity spectrum regardless of whether or not it has been subjected to a spectral sensitization treatment, and its sensitivity does not substantially change in the wavelength range of 20 ± 5 nm. be able to. As an example of the exposure light source, when the phosphor of the radiation intensifying screen used in combination is terbium activated gadolinium oxysulfide, a tungsten light source (color temperature: 2856 K °)
And a filter having a transmission peak wavelength of 545 nm and a full width at half maximum of 20 nm and being transparent.

Next, the radiation intensifying screen preferably used in the present invention will be described in detail. The radiographic intensifying screen used in the assembly of the present invention can be easily obtained by producing it so as to have the sensitivity defined in the present invention by a conventionally known radiographic intensifying screen production technique. See Research Disclosure, Item 18, for an example of an intensifying screen.
431, section IX.

The radiation intensifying screen has, as a basic structure, a support and a phosphor layer formed on one surface thereof. The phosphor layer is a layer in which the phosphor is dispersed in a binder (binder). The surface of the phosphor layer opposite to the support (the surface not facing the support) is generally provided with a transparent protective film to chemically alter the phosphor layer. Protects against physical shock.

The phosphors used in the radiation intensifying screen of the present invention are preferably those represented by the following general formula. _{M (wn) M 'n O} w X (M is a metal yttrium, lanthanum, gadolinium,
Or at least one of lutetium, M ′ is at least one rare earth element, preferably dysprosium, erbium, europium, holmium, neodymium, praseodymium, samarium, cerbium, terbium, thulium, or ytterbium, and X is Intermediate chalcogen (S, Se, or Te), or halogen, n is 0.0002 to 0.2, and w is 1 when X is halogen, and X is chalcogen. Is 2.

Specific examples of the radiation sensitizing phosphor preferably used in the radiation intensifying screen of the present invention include the following phosphors. Terbium-activated rare earth oxysulfide-based phosphor [Y ₂ O ₂ S: Tb, G
d ₂ O ₂ S: Tb, La ₂ O ₂ S: Tb, (Y, Gd)
₂ O ₂ S: Tb, (Y, Gd) ₂ O ₂ S: Tb, Tm
Etc.], terbium-activated rare earth oxyhalide-based phosphors (LaOBr: Tb, LaOBr: Tb, Tm, La
OCl: Tb, LaOCI: Tb, Tm, GdOBr:
Tb, GdOCl: Tb, etc.), thulium-activated rare earth oxyhalide-based phosphor (LaOBr: Tm, LaOC)
1: Tm, etc.). Among the above phosphors, a terbium-activated gadolinium oxysulfide (oxysulfide) -based phosphor can be mentioned as a phosphor particularly preferably used in the radiation intensifying screen of the present invention. The terbium-activated gadolinium oxysulfide phosphor is described in detail in US Pat. No. 3,725,704.

The attachment of the phosphor layer onto the support is generally carried out by utilizing a coating method under normal pressure as described below. That is, a particulate phosphor and a binder are mixed and dispersed in an appropriate solvent to prepare a coating solution, and the coating solution is subjected to radiation increase under normal pressure using a coating means such as a doctor blade, a roll coater, or a knife coater. After directly coating on the support of the sensitive screen, by removing the solvent from the coating film, or by applying the coating solution in advance on a temporary support such as a glass plate under normal pressure, then the solvent from the coating film The phosphor layer is attached to the support by removing the phosphor-containing resin thin film and peeling it from the temporary support to bond it to the support of the radiographic intensifying screen. .

The radiographic intensifying screen used in the present invention can be produced by a conventional method as described above, but it is subjected to compression treatment using a thermoplastic elastomer as described below as a binder. It is preferably manufactured by increasing the filling rate of the phosphor (that is, reducing the porosity in the phosphor layer).

The sensitivity of the radiographic intensifying screen basically depends on the total emission amount of the phosphor contained in the panel,
This total amount of light emission depends not only on the emission brightness of the phosphor itself, but also on the content of the phosphor in the phosphor layer. A large content of the phosphor also means a large absorption for radiation such as X-rays, so that higher sensitivity can be obtained and at the same time, image quality (particularly graininess) is improved.
On the other hand, when the phosphor content in the phosphor layer is constant, the denser the phosphor particles are, the thinner the layer can be made, and therefore the spread of the emitted light due to scattering is reduced. It is possible to obtain relatively high sharpness.

In order to manufacture the above-mentioned radiographic intensifying screen, a) a step of forming a phosphor sheet composed of a binder and a phosphor, and then b) placing the phosphor sheet on a support and attaching the binder. The step of adhering the phosphor sheet on a support while being compressed at a softening temperature or a temperature equal to or higher than the melting point is preferably used for the production.

In a conventional radiographic intensifying screen,
As described above, the transparent protective film for physically and chemically protecting the phosphor layer is provided on the surface of the phosphor layer on the side opposite to the side in contact with the support. It is preferable to install such a transparent protective film also in the radiation intensifying screen of the present invention.

The thickness of the protective film is generally about 0.1 to 20 μm.
It is in the range of m. The protective layer of the radiation intensifying screen is preferably a transparent synthetic resin layer having a thickness of 5 μm or less formed by coating on the phosphor layer. By using such a thin protective layer, the distance from the phosphor of the radiographic intensifying screen to the silver halide photosensitive material is shortened,
This contributes to the improvement of the sharpness of the obtained X-ray image.

The radiographic intensifying screen used in the present invention is
As mentioned above, it has high sensitivity, and its characteristic is that the contrast transfer function (CTF) is 1 spatial frequency / mm.
0.79 or more at (1p / mm) and 3 spatial frequencies /
It is preferably prepared so as to show 0.36 or more in mm (1 p / mm).

Further, the radiation intensifying screen used in the present invention has the following characteristics in a graph in which the horizontal frequency is the spatial frequency (lines / mm value) and the contrast transfer function (CTF) is the vertical axis. / Mm values and CTF values are connected in order to form a smooth curve, and a book created by a curve is compared with the relationship between / mm values and CTF values. C higher than the above curve
It is particularly preferable that it has a TF value.

The measurement and calculation of the contrast transfer function from the radiation intensifying screen to the light-sensitive material can be carried out by using a sample obtained by printing a rectangular chart on an MRE single-sided material manufactured by Eastman Kodak Company.

In the assembly of the present invention, a silver halide photographic light-sensitive material having front and rear light-sensitive layers satisfying the above-mentioned requirements for sensitivity and having substantially the same characteristics as each other is used, and both sides ( It is preferable to use a radiation intensifying screen having the above-mentioned characteristics in combination on the front side and the rear side so as to have substantially the same characteristics. However, in order to improve the balance between the image sharpness and the sensitivity, the front intensifying screen and the rear intensifying screen are combined with the fluorescence of the front intensifying screen as described in US Pat. No. 4,710,637. It is also possible to improve the balance between image quality and sensitivity by reducing the body coating amount below the phosphor coating amount of the post intensifying screen.

In the case of the assembly of the present invention, X has a sensitivity which does not cause any problems in practical use and is obtained by photographing.
In order to ensure that the image quality of the line image is at a high level, the sensitivity of the assembly is 80 KVp, and when the exposure is 0.5 to 1.5 mR when a three-phase X-ray source is used, the developer specified above is used. Also, it is preferable to use a combination of a silver halide photographic light-sensitive material and two radiation intensifying screens so that a density of 1.0 can be obtained when the development processing is performed under the developing conditions.

Next, the silver halide photographic light-sensitive material of the present invention will be described. The sensitivity of the photographic light-sensitive material of the present invention is as described above, but the total amount of silver contained in the photographic light-sensitive material needs to be 2.5 g / m ² or less as a total of both sides of the support. When the amount of silver in the light-sensitive material is more than 2.5 g / m ² , the reduction of environmental load, which is the object of the present invention, cannot be achieved. In the present invention, it is essential to have photosensitive emulsion layers on both sides of the support, and the amount of silver contained on one side is 20% or more and less than 80% of the total of both sides, preferably 40% or more and 60%.
It is less than 50%, and it is most desirable that the content is 50% on both sides of the support. The total amount of silver contained on both sides of the support is more preferably 2.3 g / m ² or less.

The photosensitive material of the present invention may have a hydrophilic colloid layer in addition to the silver halide emulsion layer, if desired, and it is preferable to provide a surface protective layer according to a known method. The amount of gelatin on the side having the hydrophilic colloid layer including the emulsion layer is preferably in the range of 2.0 g / m ² or more and less than 3.2 g / m ² , particularly 2.2 g / m ² or more and 3.0 g / m ^{2. 2}
It is desirable to set it within the range below. The melting time of the light-sensitive material of the present invention is preferably set to 8 minutes or more and 60 minutes or less. The measuring method of the melting time referred to in the present invention follows the method described in JP-A-63-221341. The hydrophilic colloid layer of the photographic light-sensitive material of the present invention has a swelling ratio in water of 1 with a known hardener.
It is preferably set to 00% or more and less than 300%, particularly 150% or more and 250% or less. The swelling ratio as used in the present invention has the same definition as described in JP-A-58-111933.

Next, the emulsion grains used in the present invention will be described. The silver halide grains in the emulsion may have a regular crystal form such as a cube or an octahedron, or may have an irregular crystal form such as a sphere, a plate or a potato, and various crystals. It may consist of a mixture of shaped particles. The composition of the silver halide grains of the present invention includes
Silver iodobromide, silver bromide, silver iodochlorobromide, silver chlorobromide, silver iodochloride,
Any of silver chloride may be used, but silver iodobromide having a silver iodide content of 0.6 mol% or less and silver chloride content of 20 mol% to 100 mol from the viewpoint of high sensitivity and excellent rapid processability. %, And particularly preferably 50 mol% or more and less than 99 mol% silver iodobromochloride or silver chlorobromide.

The use of monodisperse emulsions is a preferred embodiment for the present invention. A method for producing a monodisperse emulsion is known, and for example,
J. Photo. Sci. 12, 242-251 (1963),
Japanese Patent Publication No. 48-36890, Japanese Patent Publication No. 52-16364
No. 5, JP-A-55-142329, JP-A-57-179.
The technique described in No. 835 and the like can be appropriately used.
The emulsion of the present invention may be a core / shell type emulsion. The core / shell type emulsion is known from JP-A-54-48521.

Tabular grains are preferably used in the present invention. Regarding tabular grains, RESEARCH DISCLOSURE 22
Volume 5 Item 22534, 20-58, January issue (198
3) and JP-A Nos. 58-127921 and 58-
No. 113926, JP-A-58-113927, JP-A-58-113928, and US Pat. No. 4,439,520 can be referred to.

The projected area diameter of the tabular emulsion of the present invention is 0.
It is preferably 3 to 2.0 μm, and particularly preferably 0.5 to 1.2 μm. The thickness of the particles is preferably 0.05 to 0.3 μm, particularly preferably 0.1 to 0.25 μm, and the aspect ratio is preferably 3 or more and less than 20, particularly preferably 5 or more and less than 12. Among the tabular grains, monodisperse tabular grains are particularly useful grains. Details of the structure and manufacturing method of the monodisperse tabular grains referred to in the present invention are described in JP-A-63-151618
And JP-A-1-158426. There are no particular restrictions on the various additives used in the light-sensitive material of the present invention, and for example, the additives described in the following relevant parts can be used.

Item This section 1) Chemical sensitization method JP-A-2-68539, page 10, upper right column, line 13 to upper left column 16 line, Japanese Patent Application No. 3-105035. 2) Antifoggant JP-A-2-68539, page 10, lower left column, line 17 and stabilizer to page 11 upper left column, line 7 and page 3 lower left column, line 2 to page 4 lower left Column. 3) Color improver JP-A-62-276539, page 2, lower left column, line 7 to page 10, left lower column, line 20; JP-A-3-94249, page 6, lower left column, line 15 to Page 11, upper right column, line 19 4) Spectral sensitizing dye JP-A-2-68539, page 4, lower right column, line 4 to page 8, lower right column. 5) Surfactant JP-A-2-68539, page 11, upper left column, line 14 or from antistatic agent, page 12, upper left column, line 9 6) Matting agent, slip agent JP-A-2-68539, page 12, upper left column, line 10 or plasticizer, same upper right column, line 10; page 14 left lower column, line 10 to right lower column, line 1 . 7) Hydrophilic colloid JP-A-2-68539, page 12, upper right column, line 11 to left lower column, line 16 8) Hardener JP-A-2-68539, page 12, lower left column, line 17 to page 13, upper right column, line 6 9) Support 10) Crossover JP-A-2-264944, page 4, upper right column, line 20 or cut method, page 14 upper right column. 11) Dyes and mordants JP-A-2-68539, page 13, lower left column, line 1 to page 14, lower left column, line 9 No. 3-24537, page 14, lower left column to page 16, lower right column. 12) Polyhydroxy JP-A-3-39948, page 11, upper left column to first benzenes, page 2, lower left column, EP Patent No. 452772A. 13) Layer structure JP-A-3-198041.

The reductones which are preferably used in the developer used in the present invention are endiol type (Endiol), enaminol type (Enaminol) and enediamine type (Endiamin).
, Thiol-enol type (Thiol-Enol) and enamine-thiol type (Enamin-Thiol) are generally known as compounds. Examples of these compounds are described in US Pat.
No. 8,549, JP-A No. 62-237443 and the like. Methods for synthesizing these reductones are also well known, and are described in, for example, Tsujio Nomura and Hirohisa Omura, "The Chemistry of Reductones" (Uchida Lao Tsukuba Shinsha 1969). Next, particularly preferred specific examples of the reductones used in the present invention will be given.

[0045]

[Chemical 3]

[0046]

[Chemical 4]

[0047]

[Chemical 5]

[0048]

[Chemical 6]

[0049]

[Chemical 7]

[0050]

[Chemical 8]

[0051]

[Chemical 9]

[0052]

[Chemical 10]

The reductones used in the present invention can also be used in the form of alkali metal salts such as lithium salt, sodium salt and potassium salt. These reductones are used in an amount of 1 to 80 g, preferably 5 to 50 g, per liter of the developing solution.

The developer containing the reductone of the general formula (I) of the present invention preferably contains the 3-pyrazolidone compound represented by the general formula (II). General formula (II)

[0055]

[Chemical 11]

Here, R, R ₁ , R ₂ , R ₃ , R ₄ , R
_5's may be the same or different and each represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 4 carbon atoms, an aryl group or an aralkyl group.

Examples of the 3-pyrazolidone-based developing agent used in the present invention include 1-phenyl-3-pyrazolidone, 1-phenyl-4,4-dimethyl-3-pyrazolidone and 1-phenyl-4-methyl-4-hydroxymethyl. -3-Pyrazolidone, 1-phenyl-4,4-dihydroxymethyl-3-pyrazolidone, 1-phenyl-5-methyl-3-
Pyrazolidone, 1-p-aminophenyl-4,4-dimethyl-3-pyrazolidone, 1-p-tolyl-4,4-dimethyl-3-pyrazolidone, 1-p-tolyl-4-methyl-4-hydroxymethyl- 3-pyrazolidone and the like. The developing agent is usually 0.001 mol / liter to 1.2.
It is preferably used in an amount of mol / l.

In the developer of the present invention, a dihydroxybenzene developing agent may be used as a part of the developing agent, and as the dihydroxybenzene developing agent, hydroquinone, chlorohydroquinone, bromohydroquinone, isopropylhydroquinone, methylhydroquinone,
2,3-dichlorohydroquinone, 2,5-dichlorohydroquinone, 2,3-dibromohydroquinone, 2,
Although 5-dimethylhydroquinone and the like are available, hydroquinone is particularly preferable.

In the developer of the present invention, a p-aminophenol type developing agent may be used as a part of the developing agent, and the p-aminophenol type developing agent may be N-methyl-p-aminophenol or p-aminophenol type developing agent. -Aminophenol, N-
(Β-hydroxyethyl) -p-aminophenol, N
-(4-hydroxyphenyl) glycine, 2-methyl-
Although there are p-aminophenol, p-benzylaminophenol and the like, N-methyl-p-aminophenol is preferable among them.

Preservatives for sulfite used in the developer of the present invention include sodium sulfite, potassium sulfite, lithium sulfite, ammonium sulfite, sodium bisulfite, potassium metabisulfite and the like. The sulfite is preferably 0.2 mol / liter or more, and particularly preferably 0.4 mol / liter or more. Further, the upper limit is preferably up to 2.5 mol / liter.

The pH of the developer of the present invention is preferably in the range of 8.5 to 12. More preferably, it is in the range of pH 9 to 11. The alkaline agent used for setting the pH includes a pH adjusting agent such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium triphosphate, and potassium triphosphate.

As additives to the developing solution used other than the above components, development inhibitors such as sodium bromide, potassium bromide, potassium iodide, potassium iodide: ethylene glycol, diethylene glycol, triethylene glycol, dimethyl. Organic solvents such as formamide, methyl cellosolve, hexylene glycol, ethanol, methanol: 1-phenyl-5-mercaptotetrazole, 2
-Mercapto-based compounds such as mercaptobenzimidazole-5-sulfonic acid sodium salt, indazole-based compounds such as 5-nitroindazole, may contain antifoggants such as benztriazole-based compounds such as 5-methylbenztriazole, Research Disclosure No. 176
Volume, No. 17643, page XXI (December issue, 1978)
Year)) and, if necessary, toning agents, surfactants, defoamers, water softeners, JP-A-56-1
The amino compound described in No. 06244 may be included.

A silver stain preventing agent such as the compounds described in JP-A-56-24347 can be used in the developer of the present invention.

The developing solution of the present invention is described in JP-A-56-106.
Amino compounds such as alkanolamines described in No. 244 and European Patent Publication No. 0136582 can be used.

In addition to this, LFA. Mason, "Photographic Processing Chemistry," Focal
You may use what is described in the press publication (1966) pages 226-229, US Patent 2,193,015, 2,592,364, Unexamined-Japanese-Patent No. 48-64933 etc.

The processing liquid having fixing ability in the present invention is mainly a fixing liquid. The fixing solution is an aqueous solution containing thiosulfate as a fixing agent and has a pH of 3.8 or higher, preferably 4.0.
Has 7.0. More preferably, the pH is 4.2 to 5.5.
Is.

Examples of the fixing agent include sodium thiosulfate and ammonium thiosulfate, and sodium thiosulfate is particularly preferable from the viewpoint of environmental influence. The amount of the fixing agent used can be appropriately changed, and is generally about 0.1 to about 3 mol /
It is a liter.

Preservatives (eg sulfite, bisulfite), pH buffering agents (eg acetic acid, boric acid), pH adjusters (eg sulfuric acid), chelating agents having the ability to soften water by water are used in the fixing solution, if desired. And compounds described in JP-A-62-78551.

It may be more preferable that the washing water used in the present invention is pretreated before being supplied to the washing tank by removing dust and organic substances existing in the water through a filter member or a filter of activated carbon.

Japanese Patent Laid-Open No. Sho 6-1994, which is known as an anti-fungal means.
0-263939, UV irradiation method, 60-
Method using magnetic field described in No. 263940, 61-
A method for producing pure water using the ion exchange resin described in No. 131632, Japanese Patent Application Nos. 2-208638 and 2-3.
No. 03055, a method of circulating a filter and an adsorbent column while blowing ozone, Japanese Patent Application No. 3-2
Method by microbial degradation described in Japanese Patent No.
2-115154, 62-153952, 62
The methods using the antibacterial agents described in Nos. -220951 and 62-209532 can be used in combination.

Furthermore, MW Beach, "Microbiological G
rowths in Motion-picture Processing "SMPTE Journal
Vol.85 (1976), RODeegan, "Photo Processing Wash
Water Biocides "J. Imaging Tech. Vol.10, No.6 (1984)
And JP-A-57-8542 and 57-58143.
No. 58-105145, No. 57-132146.
No. 58, No. 58-18631, No. 57-97530, No. 57-257244, etc., may be used in combination, if necessary.

Furthermore, the washing bath (or stabilizing bath) can be used as required by RT Kreiman, J. Image. Tech. Vo.
l.10, No.6, p.242 (1984), isothiazoline compounds, bromochlorodimethylhydantoin, Rese
arch Disclosure Volume 205, No. 20526 (198
May 1st), Volume 228, No. 22845 (198)
3rd, April issue), isothiazoline compounds,
The compounds described in JP-A-62-209532 may be used in combination as a bacteriostatic agent (Microbiocide), if necessary.

In addition, "Chemistry of antibacterial and antifungal" by Hiroshi Horiguchi,
Compounds such as those described in Sankyo Publishing (Showa 57), "Handbook of Antibacterial and Antibacterial Technology", Japan Society for Antibacterial and Antibacterial Agent, Hakuhodo (Showa 61) may be included.

In the method of the present invention, JP-A-63-1 is used.
A squeeze roller cleaning tank described in No. 8350 may be provided. Further, it is also preferable to adopt a constitution of a water washing step as disclosed in JP-A-63-143548.

Further, a part or all of the overflow liquid from the washing tank produced by supplementing the washing or stabilizing bath with anti-fouling water according to the method according to the present invention is disclosed in JP-A-60 / 60. As described in JP-A-235133, it is effective to utilize the fixing ability, which is the previous processing step, in the processing liquid.

The developing time is 5 seconds to 3 minutes, preferably 6 seconds to 1 minute, and the developing temperature is 18 ° C. to 5 minutes.
0 degreeC is preferable and 20 degreeC-40 degreeC is more preferable.

According to the present invention, the fixing temperature and time are about 18 ° C.
To about 50 ° C. for 5 seconds to 3 minutes are preferred, and 20 ° C. to 40 ° C. for 6 seconds to 1 minute are more preferred.

The temperature and time for washing (or stabilizing bath) are 0 to
It is preferably 6 seconds to 3 minutes at 50 ° C, more preferably 6 seconds to 1 minute at 10 ° C to 40 ° C.

According to the invention, the developed, fixed and washed (or stabilized) photographic material is squeezed out of the wash water, ie dried via a squeeze roller. The drying is carried out at about 40 ° C. to about 100 ° C., and the drying time may be appropriately changed depending on the ambient conditions, but it is usually about 5 seconds to 3 minutes, and particularly preferably 40 to 80 ° C. for about 5 seconds to 1 minute. Minutes.

Dry to Dry 1 in the processing system of the present invention
When developing for less than 00 seconds, a roller made of a rubber material as described in JP-A-63-151943 is applied to the roller at the outlet of the developing tank in order to prevent development unevenness peculiar to rapid processing. Kotoya, JP-A-63-1
As described in JP-A-51944, the discharge flow rate for stirring the developer in the developer tank is set to 10 m / min or more, and further, it is described in JP-A-63-264758. Thus, it is more preferable to stir more strongly than during standby at least during the development process. Hereinafter, the present invention will be specifically described with reference to examples.

[0081]

【Example】

Example 1 Preparation of Intensifying Screen A As a coating solution for forming a phosphor sheet, a phosphor (Gd ₂ O ₂
S: Tb) 200 g, Binder A (Polyurethane, manufactured by Sumitomo Bayer Urethane Co., Ltd., trade name: Desmolac TPK
L-5-2625 [solid content 40%]) 20 g, and binder B (nitrocellulose, nitrification degree 11.5%) 2 g
Was added to a methyl ethyl ketone solvent and dispersed by a propeller mixer to prepare a coating liquid having a viscosity of 30 PS (25 ° C.) (binder / phosphor ratio = 1/20). This was applied onto polyethylene terephthalate (temporary support, thickness 180 μm) coated with a silicone-based release agent so that the film thickness after pressure compression treatment described below would be 160 μm, dried, and then temporarily supported. It was peeled from the body to form a phosphor sheet. Separately, as an undercoat layer forming coating solution, 90 g of a soft acrylic resin and 50 g of nitrocellulose were added to methyl ethyl ketone and mixed and dispersed to have a viscosity of 3 to 6 PS (25 ° C.).
A dispersion of was prepared.

Thickness of 250 μm in which titanium dioxide is kneaded
Polyethylene terephthalate (support) is placed horizontally on a glass plate, the above coating solution for forming the undercoat layer is uniformly applied on the support using a doctor blade, and then the temperature is gradually increased from 25 ° C to 100 ° C. And the coating film was dried to form an undercoat layer on the support (coating film thickness:
15 μm). The phosphor sheet prepared first was placed on this, and pressure compression operation was performed using a calender roll at a pressure of 400 Kgw / cm ² and a temperature of 80 ° C.

Separately, a fluororesin (fluorofine
Vinyl ether copolymer, Asahi Glass Co., Ltd., trade name: Lumiflon LF100) 70 g, cross-linking agent (isocyanate, Sumitomo Bayer Urethane Co., Ltd., trade name: Desmodur Z4370) 25 g, bisphenol A type epoxy resin 5 g, and alcohol Modified silicone oligomer (having dimethylpolysiloxane skeleton and having hydroxyl groups (carbinol groups) at both ends, Shin-Etsu Chemical Co., Ltd.)
Product name: X-22-2809 (5 g), product name, was added to a mixed solvent of toluene / isopropyl alcohol (1: 1, volume ratio) to prepare a coating liquid for forming a protective film. The above coating solution for forming a protective film is applied to the surface of the phosphor sheet that has been subjected to a pressure compression operation on a support using a doctor blade,
It was heat-treated at 120 ° C. for 30 minutes, dried and heat-cured to form a transparent protective film having a thickness of 3 μm. As described above, a radiation intensifying screen A including a support, an undercoat layer, a phosphor layer, and a transparent protective film was produced.

Measurement of characteristics of radiation intensifying screen 1) Measurement of X-ray absorption amount X-rays generated from a tungsten target tube operated at 80 KVp with three-phase power supply were transmitted through an aluminum plate having a thickness of 3 mm. , The sample radiation intensifying screen fixed at a position 200 cm from the tungsten anode of the target tube, and then the amount of X-rays transmitted through the intensifying screen at a position 50 cm after the phosphor layer of the intensifying screen. The amount of X-ray absorption was determined by measurement using an ionization type dosimeter. In addition, as a reference, the X-ray dose at the above-mentioned measurement position measured without passing through the intensifying screen was used. Table 1 shows the measured X-ray absorption of each intensifying screen used in the experiment.

2) Measurement of Modulation Transfer Function (CTF) An MRE single-sided photosensitive material manufactured by Eastman Kodak Co. was placed in contact with an intensifying screen to be measured, and a rectangular chart for MTF measurement (made of molybdenum, thickness: 80 μm). , Spatial frequency: 0 lines / mm to 10 lines / mm) were photographed. The chart was placed 2 m from the X-ray tube, the photosensitive material was placed in front of the X-ray source, and then the intensifying screen was placed.

The X-ray tube used was DRX- manufactured by Toshiba Corporation.
3724HD, using a tungsten target,
The focal spot size is 0.6 mm × 0.6 mm, and X-rays are generated through the aluminum equivalent material of 3 mm including the diaphragm. 80KVp with pulse generator for three phases
The light source was an X-ray that passed through a 7 cm-filter of water, which had absorption almost equivalent to that of the human body. The photosensitive material after shooting was Dry to Dr at a developing temperature of 33 ° C. by a roller-conveying type automatic developing machine CEPROS-M manufactured by Fuji Photo Film Co., Ltd.
y The treatment was performed for 90 seconds.

Next, the measurement sample was operated with a microdensitometer. The operating direction of the aperture at this time is 30μ
The concentration profile was measured at a sampling interval of 30 μm using a slit of m, and a vertical direction of 500 μm. Repeat this operation 20 times to calculate the average value,
The concentration profile was used as the basis for calculating CTF.
After that, the peak of the rectangular wave for each frequency in this density profile was detected, and the density contrast for each frequency was calculated. Table 1 shows values measured for spatial frequencies of 1 line / mm and 3 lines / mm.

3) Measurement of Sensitivity The same X-ray source as that used in the CTF measurement was used, and a green-sensitized Eastman Kodak MRE single-sided photosensitive material was combined, and the X-ray exposure amount was measured by the distance method. To change l
Stepwise exposure was performed with a width of ogE = 0.15. After the exposure, the photosensitive material was developed under the same conditions as in the CTF measurement to obtain a measurement sample. The density of the measurement sample was measured with visible light to obtain a characteristic curve. The sensitivity was expressed by the reciprocal of the X-ray exposure amount to obtain a density of 1.8, and the relative sensitivity was examined by using the rear side intensifying screen HR-4 as a reference ("100"). The results are shown in Table 1.

[0089]

[Table 1]

From Table 1, it can be seen that HR-8 and intensifying screen A satisfy the requirements of claim 1 and only intensifying screen A satisfies the requirements of claim 5.

Preparation of photographic light-sensitive material (1) Preparation of high-sensitivity tabular emulsion Tf Potassium bromide 6.9 g, average molecular weight 1 in 1 liter of water.
6.00 g of low molecular weight gelatin (5,000 g) was added, and while stirring in a container kept at 55 ° C, 37 cc of an aqueous solution of silver nitrate (2.4 g of silver nitrate) and an aqueous solution containing 5.9 g of potassium bromide 38
cc was added by the double jet method in 37 seconds. Next, after adding 18.6 g of gelatin, the temperature was raised to 70 ° C. and 100 cc of silver nitrate aqueous solution (silver nitrate 11.2 g) was added over 22 minutes. Here, 8.5 cc of 25% aqueous ammonia solution was added, and after physically aging for 10 minutes at the same temperature, 8 cc of 100% acetic acid solution was added. Subsequently, an aqueous solution of 145 g of silver nitrate and an aqueous solution of potassium bromide were added to pAg.
While accelerating the flow rate by the control double jet method while maintaining it at 8.5 (initial flow rate / final flow rate = 1 / 5.4)
Added over 35 minutes. Then, 35 cc of 2N potassium thiocyanate solution was added. After physically aging for 5 minutes at the same temperature, the temperature was lowered to 35 ° C. Pure silver bromide tabular grains having an average projected area diameter of 1.05 µm to a thickness of 0.155 µm and a diameter variation coefficient of 20% were obtained.

After that, soluble salts were removed by the coagulation sedimentation method. The temperature was again raised to 40 ° C., 35 g of gelatin, 2.35 g of phenoxyethanol, and 0.8 g of sodium polystyrene sulfonate as a thickener were added, and the pH was adjusted to 5.90 and pAg to 8.00 with caustic soda and silver nitrate solution. This emulsion was chemically sensitized while being kept at 56 ° C. with stirring. First, C ₂ H ₅ SO ₂ SNa is added at 1 × 10 ⁻⁵ mol /
Mol Ag was added, then 0.001 mol of AgI fine particles having a particle size of 0.03 μm was added, and then 4-hydroxy-
6-methyl-1,3,3a, 7-tetrazaindene 20
480 mg of sensitizing dye- (I) was added. Further, 0.83 g of calcium chloride was added. Subsequently, 0.9 mg of sodium thiosulfate, 1.9 mg of selenium compound- (I), 1.9 mg of chloroauric acid and 90 mg of potassium thiocyanate were added, and 40 minutes later, the mixture was cooled to 35 ° C. Thus, preparation of tabular grain emulsion Tf was completed.

[0093]

[Chemical 12]

(2) Preparation of low-sensitivity fine grain tabular emulsion Ts This was prepared by changing the following points from the high-sensitivity tabular emulsion Tf. First, the temperature during particle formation was changed to 38 ° C. In this way, pure silver bromide tabular grains having an average projected area diameter of 0.68 μm, a thickness of 0.123 μm and a diameter variation coefficient of 23% were obtained.

Further, the chemical addition amount at the time of chemical sensitization was changed. 0.003 mol of AgI fine particles having a particle diameter of 0.03 μm, 4-hydroxy-6-methyl-1,3,3a, 7-
Tetrazaindene 100 mg, sodium thiosulfate 1.
8 mg and selenium compound (I) were changed to 3 mg (other conditions were the same as Tf). Thus, the preparation of the low-sensitivity fine grain tabular emulsion Ts was completed.

(3) Preparation of Support X Preparation of Dye Dispersion A for Undercoat Layer The following Dye- (I) was ball-milled by the method described in JP-A-63-197943.

[0097]

[Chemical 13]

434 ml of water and 791 ml of a 6.7% aqueous solution of Triton X-200 surfactant (TX-200) were placed in a 2 liter ball mill. 20 g of dye were added to this solution. Zirconium oxide (ZrO ₂ ) beads 4
00 ml (2 mm diameter) was added and the contents were milled for 4 days.
After this, 160 g of 12.5% gelatin was added. After defoaming, the ZrO ₂ beads were removed by filtration. Observing the obtained dye dispersion, the particle size of the crushed dye has a wide range of diameters from 0.05 to 1.15 μm, and the average particle size was 0.37 μm. Further, centrifugation was performed to remove dye particles having a size of 0.9 μm or more. Thus, Dye Dispersion A was obtained.

Preparation of Support Corona discharge treatment was performed on a biaxially stretched blue-colored polyethylene terephthalate film having a thickness of 175 μm, and a first undercoat liquid having the following composition was applied at an amount of 4.
It was coated with a wire bar coater so as to be 9 cc / m ² and dried at 185 ° C. for 1 minute. Next, a first undercoat layer was similarly provided on the opposite surface.・ Butadiene-styrene copolymer latex solution (solid content 40% butadiene / styrene weight ratio = 31 to 69) 158cc ・ 2,4-dichloro-6hydroxy-s-triazine sodium salt 4% solution 41cc ・ Distilled water 300cc On the first undercoat layer on both sides, a second undercoat element having the following composition is applied on each side so that the coating amount is as described below, and at 155 ° C. on both sides by a wire bar coater method.
It was applied and dried.・ Gelatin 160 mg / m ²・ Dye Dispersion A (as dye solid content) 8 mg / m ²・ C ₁₂ H ₂₅ O (CH ₂ CH ₂ O) ₁₀ H 1.8 mg / m ²・ Proxel 0.27 mg / m ² Matting agent Polymethylmethacrylate having an average particle size of 2.5 μm 2.5 mg / m ^{2 In} this way, the support X including the crossover cut layer was prepared.

(4) Preparation of Coating Solution The following chemicals were added to 1 mol of silver halide in the tabular emulsions Tf and Ts to prepare a coating solution.・ 2,6-bis (hydroxyamino) -4-diethylamino-1,3,5-triazine 72 mg ・ Dextran (average molecular weight 39,000) 18.5 g ・ Sodium polystyrene sulfonate (average molecular weight 600,000) 1.8 g -Gelatin For each coated sample, the addition amount was adjusted so that the coating amount of gelatin in the emulsion layer was 1.6 g / m ² .・ Hardener 1,2-bis (vinylsulfonylacetamide) ethane 2.2 g

[0101]

[Chemical 14]

The surface protective layer was prepared and prepared so that the amounts of the components were as follows. (Protective layer coating solution) Gelatin 800 g-dextran (average molecular weight _{39,000) 200g · C 16 H 33 O} (CH 2 CH 2 O) 10 H 39g · C 8 F 17 SO 2 N (C 3 H 7) (CH ₂ CH ₂ O) ₄ (CH ₂ ) SO ₃ Na 1.6 g ・ C ₈ F ₁₇ SO ₃ K 7 g ・ Polymethylmethacrylate particles (average particle size 3.7 μm) 91 g ・ Proxel 0.7 g ・ Polyacrylic acid Sodium (average molecular weight 41,000) 45 g ・ Sodium polystyrene sulfonate (average molecular weight 600,000) 3 g ・ NaOH 1.6 g ・ C ₈ H ₁₇ C ₆ H ₄ (OCH ₂ CH ₂ ) ₃ SO ₃ Na 24 g

[0103]

[Chemical 15]

-Add distilled water to 14 liters and complete

(5) Preparation of photographic material The coating solution prepared in (4) was applied simultaneously on both sides of the support prepared in (3) by the simultaneous extrusion method under the same conditions. The amount of gelatin in the protective layer was 0.75 g / m ² . Silver coverage, for tabular emulsion Tf, and per side 1.65 g / m ² of the support (both sides 3.3 g / m ^2), with 1.15 g / m ² (on both sides per side with respect to Ts 2 0.3 g /
m ² ). Thus, the preparation of photographic materials 1 (emulsion Tf) and 2 (emulsion Ts) was completed. The swelling ratios of the obtained photographic materials 1 and 2 were measured according to the means and definition described in JP-A-58-11193.
%Met. Also, U.S. Pat. No. 4,425,425,
According to the means and definition described in No. 4,425,426,
When the crossover light of the photographic materials 1 and 2 was measured,
Each was 16% identical.

Sensitometry The light-sensitive material to be evaluated was sandwiched with each screen shown in Table 1, the X-ray exposure amount was changed by the distance method, and stepwise exposure was performed with a width of logE = 0.15. The X-ray tube used is a Toshiba DRX-3724HD,
The X-ray is generated by using a tungsten target, having a focal spot size of 0.6 mm × 0.6 mm, passing through an aluminum equivalent material of 3 mm including the diaphragm.
A voltage of 80 KVp was applied to the three phases with a pulse generator, and an X-ray that passed through a filter of 7 cm of water having absorption almost equivalent to the human body was used as a light source. The photosensitive material after shooting is a roller transport type automatic developing machine CEPROS-M manufactured by Fuji Photo Film Co., Ltd.
Dry to Dry 45 seconds processing was carried out at a developing temperature of 35 ° C. The density of each measurement sample was measured with visible light to obtain a characteristic curve. The reciprocal of the X-ray exposure amount required to obtain the density of 1.5 was taken as the sensitivity and shown as a relative value. The results are shown in Table 2. Although the X-ray sensitivity of the assembly changed depending on the combination of each light-sensitive material and the screen, the gradation, Dmax, and all combinations were the same.
The slope (gamma) of the straight line connecting the points 1 was 2.6.

Image evaluation by phantom: Chest phantom manufactured by Kyoto Chemical Co., Ltd., Burger phantom concave, convex, three-phase 12 pulse 100 KVp (equipped with 3 mm thick aluminum equivalent filter), focal spot size 0.6 mm × 1. Using a 6 mm X-ray source, distance 1
A phantom was placed at a position of 40 cm, and then a scattered ray cut grid having a grid ratio of 8: 1 was placed, and thereafter, an assembly of a light-sensitive material and an intensifying screen was placed, and a photographing was performed. The development processing was performed at 35 ° C. for 45 seconds using the automatic developing machine CEPROS-M and the developing solution CE-D1 as in the case of measuring the photographic characteristics. In the Burger Phantom, the density of the flat part becomes 1.5,
The X-ray exposure amount was adjusted by changing the exposure time. In the chest phantom, a certain point in the lung field was defined, and the X-ray exposure amount was adjusted by changing the exposure time so that the density became 1.8. The finished phantom photographs were arranged on a Schaukasten and visually evaluated. The visibility of blood vessel shadows in the lung field, the ease of identifying irregularities in the Burger phantom, and the graininess of photographs (due to X-ray quantum mottle, screen structure mottle, and graininess of sensitive material) It was evaluated, and A was extremely good, B was good, C was manageable, and D was not possible. The results are summarized in Table 2.

[0108]

[Table 2]

From the results shown in Table 2, the following facts became clear. First, in a separate comparison experiment, the intensifying screen H
The combination of R-4 and photographic material 1 (Tf) had almost the same sensitivity as the intensifying screen HR-4 and Ortho X-Ray Film Super HRS manufactured by Fuji Photo Film Co., Ltd.
On the other hand, when the low-sensitivity intensifying screen HR-3 is used, even when the high-sensitivity photographic material 1 (Tf) is used, it is half of HR-4 / photographic material 1 (Tf). There is only sensitivity. Therefore, in the assembly using HR-3, the exposed X-ray dose for diagnosis is doubled. By doubling the X-ray irradiation dose, the X-ray quantum mottle is greatly reduced and the graininess is improved. Also CT of HR-3 screen itself
Since F is high, the discriminating property and the graininess are improved. However, if the specific sensitivity of the assembly decreases to the level of Experiment No. 2, no matter how excellent the image quality is, the practical value decreases due to the increase in the X-ray irradiation dose.

On the other hand, in the high-sensitivity screen HR-8 and the combination of the intensifying screen A and the photographic material 1 (Tf), the specific sensitivity is increased, resulting in an increase in X-ray quantum noise. As a result, the graininess is significantly deteriorated and the distinctiveness is also lowered, and the practical value is low (Experiment Nos. 5 and 7). Such a system is useful when the exposure is limited, such as children and pregnant women.

On the other hand, the assembly of the present invention (Experiment No. 6
In and 8), a significant improvement in graininess was realized while maintaining a specific sensitivity of 100. Although the CTF of the HR-8 intensifying screen itself was lower than that of HR-4, the graininess was dramatically improved.
It gave the same distinctiveness as the combination with 4. Also, the smooth graininess reduced eye fatigue at the time of diagnosis, and was highly evaluated for its practical value. Furthermore, the combination of the intensifying screen A of the present invention and the photographic material 2 (Ts) achieved high sensitivity and excellent distinguishability and graininess. From the above, the effect of the present invention is clear.

Example 2 Using the photographic materials 1 (Tf) and 2 (Ts) of Example 1, X-ray exposure was carried out with the composition of Experiment Nos. 4 and 8 in Table 2 and then the following. Was processed.

As the automatic developing machine, "Fuji X Ray Processor CEPROS-M" manufactured by Fuji Photo Film Co., Ltd. was modified so that the conveying speed and the amount of developing / fixing replenisher were variable. The treatment liquid used is as follows. <Developer I> PartA potassium hydroxide 18.0 g potassium sulfite 75.0 g sodium carbonate 30.0 g boric acid 5.0 g diethylene glycol 10.0 g diethylenetriaminepentaacetic acid 2.0 g 1- (N, N diethylamino) ethyl-5-mercapto Tetrazole 0.1 g Hydroquinone 27.0 g 4-Hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone 2.0 g Water was added to 300 ml.

Part B Triethylene glycol 45.0 g 3.3 ′ ′-Dithiobishydrocinnamic acid 0.2 g Glacial acetic acid 5.0 g 5-Nitroindazole 0.3 g 1-phenyl-3-pyrazolidone 3.5 g Water 60 ml

PartC Glutaraldehyde (50%) 10.0 g Potassium bromide 4.0 g Potassium metabisulfite 10.0 g Water was added to 50 ml PartA 300 ml, PartB 60 ml and PartC5.
Water was added to 0 ml to make 1 liter, and the pH was adjusted to 10.50 to prepare a working solution.

<Fixer I> Ammonium thiosulfate (70 wt / vol%) 200 ml Ethylenediaminetetraacetic acid disodium dihydrate 0.03 g Sodium sulfite 15.0 g Boric acid 4.0 g 1- (N, N-dimethylamino)- Ethyl-5-mercapto tetrazole 1.0 g Tartaric acid 3.0 g Sodium hydroxide 15.0 g Sulfuric acid (36N) 3.9 g Aluminum sulfate 10.0 g Water was added to 1 liter (adjusted to pH 4.60).

Using Developer I and Fixer I, the replenishment amount and the transport line speed were changed as shown in Table 3, and a running test was conducted. Running is development 35 ° C fixing 3
Performed at 2 ℃, of the photographic material 775cm ² to 1 day 1 (T
f) or 2 (Ts) was processed on 100 sheets (average developed silver amount rate: 40%), and the change in photographic performance was examined while continuing the experiment for 20 consecutive days. The results are summarized in Table 3.

[0118]

[Table 3]

From the results shown in Table 3, it can be seen that the photographic light-sensitive material of the present invention shows a very small fluctuation in sensitivity in the running test and stably realizes high sensitivity. Further, when the amount of the replenisher liquid is reduced to reduce the processing waste liquid to cope with the environmental problem, the comparative example is significantly desensitized on the 20th day. On the other hand, the advantage of the present invention is that such a system, that is, Sd ≦ 1
5, it can be seen that it is extremely remarkably expressed in the system of Sf ≦ 15 and T ≦ 150.

Example 3 The same experiment as in Example 2 was conducted using the following developing solution II and fixing solution II. <Developer II> PartA Potassium hydroxide 18.0 g Potassium sulfite 30.0 g Sodium carbonate 30.0 g Diethylene glycol 10.0 g Diethylenetriaminepentaacetic acid 2.0 g 1- (N, N diethylamino) ethyl-5-mercaptotetrazole 0.1 g L -Ascorbic acid 43.2 g 4-Hydroxymethyl-4-methyl-1-phenyl-3-pyrazolidone 2.0 g Water was added to 300 ml.

PartB Triethylene glycol 45.0 g 3.3'-Dithiobishydrocinnamic acid 0.2 g Glacial acetic acid 5.0 g 5. Nitroindazole 0.3 g 1-Phenyl-3-pyrazolidone 3.5 g Water 60 ml

PartC Potassium bromide 4.0 g Potassium metabisulfite 10.0 g Water was added to 50 ml PartA 300 ml, PartB 60 ml and PartC5.
Add water to 0 ml to make 1 liter and adjust to pH 10.20.

<Fixer II> Sodium thiosulfate 250 g Ethylenediaminetetraacetic acid disodium dihydrate 0.03 g Sodium sulfite 15.0 g Boric acid 4.0 g 1- (N, N-dimethylamino) -ethyl-5-mercapto Tetrazole 1.0 g Tartaric acid 3.0 g Sodium hydroxide 15.0 g Sulfuric acid (36N) 3.5 g Water was added to 1 liter (adjusted to pH 5.10)

A running experiment was conducted in the same manner as in Example 2. For the evaluation of photographic sensitivity, Example 2 experiment
Relative evaluation was performed based on the results of No. 9. The results are summarized in Table 4.

[0125]

[Table 4]

From the comparison between Table 4 and Table 3, it was found that harmful components such as hydroquinone and glutaraldehyde were removed, and L-
It can be seen that the effect of the present invention is more remarkably exhibited in the developer II using ascorbic acid as a developing agent.

Example 4 Preparation of silver chlorobromide tabular grains Tl To 6 liters of a vigorously stirred 3% gelatin, 0.47M potassium chloride, 0.01M potassium bromide solution at 45 ° C.
1.72M potassium bromide solution (potassium chloride 1.24M) and 2.0M silver nitrate solution were added by double jet in 2 minutes to keep the pAg read before the start of halide and silver addition (total used. Consume 3.8% of silver nitrate). The addition of the two solutions was then continued for 64 minutes in an accelerated flow (3 times from start to end or 3 times faster at start at the end), during which the pAg was held unchanged and 96. 2% was consumed.
The molar concentration of chlorine and bromide ions in the reaction vessel during the precipitation formation was kept constant at 0.48M and the molar ratio of chloride ion to bromide ion was 47: 1. A total of 4 moles of silver nitrate was used. After this, 2N of potassium thiocyanate
140 cc of the solution was added to complete the grain formation.

Then, soluble salts were removed by the coagulation sedimentation method. After that, redispersion was performed in the same manner as in the low-sensitivity tabular emulsion Ts of Example 1, and then chemical sensitization was performed.
Thus, the average projected area diameter is 0.72 μm and the thickness is 0.1.
A silver chlorobromide emulsion Tl having a diameter of 25 μm and a variation coefficient of 28% was obtained. The silver chloride content of the emulsion was 13 mol%.

Preparation of Silver Chlorobromide Emulsion Th The following solutions were prepared. Solution (1) Inert gelatin 10g NaCl 4g H ₂ O 1750cc

[0130]

[Chemical 16]

Solution (2) AgNO ₃ 34g H ₂ O was added to 200cc solution (3) NaCl 12.5g H ₂ O was added to 200cc solution (4) AgNO ₃ 102g H ₂ O was added to 600cc solution (5) The solution (1) kept at 600 cc and 35 ° C. by adding NaCl 37.5 g H ₂ O was simultaneously added to the solution (2) and the solution (3) over 5 minutes while vigorously stirring. After further raising the temperature to 45 ° C., the solution (4) and the solution (5) were simultaneously added over 30 minutes.

Then, 3 mol% of pure silver bromide fine particles (particle size 0.03 μm) was added to silver chloride, and 35 cc of 2N potassium thiocyanate solution was further added.
After that, the soluble salts were removed and redispersed in the same manner as in the emulsion Tl to carry out chemical sensitization. Thus, a silver chlorobromide tabular emulsion Th was obtained. The silver chloride content of emulsion Th was 97 mol%. The adjusted silver chloride emulsion has a thickness of 0.3μ
less than m, diameter 0.5 μm or more, parallel (111)
80% or more (projected area) of tabular grains having an aspect ratio of 2 or more composed of planes are present, the average projected area diameter of the tabular grains is 0.75 μm, and the average thickness thereof is 0.1.
The average aspect ratio was 3 μm and was 5.8.

Preparation of Photographic Material The photographic materials 3 (Tl) and 4 (Th) were completed in exactly the same manner as the preparation of the photographic material 2 (Ts) of Example 1.

Running Test A running test was conducted in exactly the same manner as in Example 3, except that the automatic developing machine was changed to a modified machine of "CEPROS-S" manufactured by Fuji Photo Film Co., Ltd. The results are summarized in Table 5. The photographic sensitivity is shown as a relative value with 100 on the first day of photographic material 3 (Tl).

[0135]

[Table 5]

From the results shown in Tables 4 and 5, it is understood that the effect of the present invention becomes more remarkable as the silver chloride content increases.

Claims (6)

[Claims] 1. A radiographic image forming assembly comprising a silver halide photographic light-sensitive material having a light-sensitive emulsion layer on both sides of a support, and two radiographic intensifying screens arranged before and after the light-sensitive material. (1) At least one of the radiographic intensifying screens is a radiographic intensifying screen exhibiting an absorption amount of 25% or more for X-rays having an X-ray energy of 80 KVp, and (2) a silver halide photographic material. The assembly for radiographic image formation, wherein the total amount of silver contained in each of the both sides of the support is 2.5 g / m ² or less. 2. A silver halide photographic light-sensitive material characterized in that the total amount of silver contained in the silver halide photographic material is 2.5 g / m ² or less on both sides of the support, and A method of processing a silver halide photographic material, characterized in that the following relationship is satisfied in a method of processing with an automatic processor while replenishing a fixing solution. Sd ≦ 15, Sf ≦ 15, T ≦ 150 where Sd is the replenishing amount of developing solution per 775 cm ^{2 of the} photosensitive material (ml), Sf is the replenishing amount of fixing solution per 775 cm ^{2 of the} photosensitive material (ml), T represents the time (seconds) from the time when the tip of the photosensitive material is inserted into the automatic processor to the time when the tip passes through the drying zone and comes out. 3. The automatic development processing method according to claim 2,
A method for developing a silver halide photographic light-sensitive material, wherein the silver halide photographic light-sensitive material is exposed in combination with the radiation intensifying screen according to claim 1. 4. A method for automatically developing a silver halide photographic light-sensitive material according to claim 2 or 3, wherein the developer uses a reductone represented by the general formula (1) as a developing agent. Characterized processing method. General formula (1) Here, R is a hydrogen atom or a hydroxyl group, and n is 1 to 4
Is an integer. 5. The radiation intensifying screen for exposing the silver halide photographic light-sensitive material according to claim 3 or 4, wherein at least one of (1) X-ray energy is 25% with respect to X-rays having an energy of 80 KVp.
It is a radiographic intensifying screen showing the above absorption amount. (2) The contrast transfer function (CTF) is
0.79 or more at lines / mm, 0.36 at spatial frequency 3 lines / mm
A method for developing a silver halide photographic light-sensitive material exposed by a radiation image forming assembly, which is described above. 6. The silver halide photographic material according to any one of claims 1 to 5, wherein the silver halide grains of the silver halide photographic light-sensitive material have a halogen composition of 20 mol% or more. And a radiation intensifying screen, and a method for developing and processing the silver halide photographic material.