JPH04177237A - Silver halide photosensitive material for x-ray having improved sharpness - Google Patents

Abstract

PURPOSE:To ensure the high sensitivity of a photosensitive material and the superior sharpness of image by keeping a sensitivity difference between sensitive emulsion on both sides of the material, and using specified silver halide particles. CONSTITUTION:In the silver halide photosensitive material wherein the sensitivity of emulsion on one side is higher than the sensitivity of emulsion surface on the other side by 2.5 to 10.0 times, and a total silver amount contained in the silver halide of the higher sensitive emulsion side is 1.2 to 4.0 times larger than on the other side, silver halide particles contain a combination of at least one of absorptive photo-spectral sensitizing pigments, and at least one of absorptive luminous pigments easily removed through a development process. In this case, only one side of the material is exposed in photographing. According to this construction, the sharpness of image can be substantially improved, and a silver halide photosensitive material having quick development processing characteristics without any drop in sensitivity can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an X-ray silver halide photographic light-sensitive material that has excellent image sharpness, high detectability, and rapid processability. It is.

[Background of the invention]

X-ray photography used for medical diagnosis is generally carried out by sandwiching a film coated with emulsion on both sides between two fluorescent intensifying screens and holding it in a cassette.

In order to effectively utilize a small amount of X-rays in consideration of the effect on the human body, the X-rays that have passed through the front intensifying screen are further used in the rear intensifying screen.

Traditionally, when observing images with films that have emulsion layers on both sides of the support, one sees both the image on the front surface that is directly visible to the eye, and the image on the back surface that passes through the base of the support and is visible to the eye. Become. Therefore, there is no problem when the image is viewed at right angles to the support, but when viewed from an angular position, a "shift" occurs between the front and back images, resulting in a decrease in sharpness.

Also, when taking X-rays, the incident angle is 9 to the film surface.
Although it is common to take images with the X-ray angle at 0 degrees, even in this case, the angle of incidence from the source of the X-rays still spreads by about 17 degrees.

Furthermore, in some cases, images are taken at an angle of oblique incidence, and in such cases, with a double-sided emulsion film, the "shift" between the front and back images is further magnified, resulting in a significant decrease in sharpness.

In recent years, X-ray imaging systems have rapidly advanced in higher image quality and faster processing, and in particular higher sensitivity and sharpness have improved breast cancer,
It is an indispensable element in the diagnosis of diseases such as lung cancer.

For this reason, attempts have been made to use films with single-sided emulsion for these diagnoses, but while this certainly improves sharpness, it results in a lack of sensitivity, so as mentioned above, light transmission to the back side (crossover light ), the reality is that a double-sided emulsion film with high sensitivity is unavoidably used even if a "blurred image" is produced.

One of the measures to increase sensitivity is to increase the amount of silver coated in the emulsion, but increasing the amount of silver decreases the fixing speed, generates residual silver, and slows drying. This is not preferable because it goes against the processability.

In particular, shortening the processing time of X-ray film is considered to be an indispensable element in intraoperative angiography in the surgical field, where blood coagulates due to a catheter in a blood vessel.

As described above, there is an urgent need to improve the sensitivity of photosensitive materials, which is an issue in current X-ray systems, and to establish new technologies that can easily obtain high-sharp images through rapid processing. Ta.

[Purpose of the invention]

Therefore, a first object of the present invention is to provide a silver halide photographic material for X-rays which is highly sensitive and has excellent sharpness.

A second object of the present invention is to provide a silver halide photographic material for X-rays that has increased sensitization efficiency without deteriorating its rapid development processability.

Other objectives will become apparent from the description below.

[Structure of the invention]

MEANS TO SOLVE THE PROBLEM It was discovered that the said objective of this invention was achieved by the following structure, and the present invention was accomplished.

That is, in a silver halide photographic material having at least one light-sensitive silver halide emulsion layer on both sides of a transparent support, the sensitivity of the emulsion surface on one side is different from the sensitivity of the emulsion layer on the other side. A silver halide photographic sensitizer which is 2.5 to 1O60 times more sensitive and has a total silver amount of silver halide on the high-sensitivity emulsion side that is 1.2 to 4.0 times that on the other side. In the material, the silver halide grains contain a combination of at least one absorbable photographic spectral sensitizing dye and at least one non-adsorbable luminescent dye that is easily removed by development processing. This can be achieved using silver halide photographic materials.

The present invention will be explained in detail below.

In the present invention, emulsion layers are coated on both sides of a support, and unlike conventional methods, the present invention is characterized in that a sensitivity difference is created between the photosensitive emulsions on both sides. Moreover, when photographing, exposure is done from only one side.

The sensitivity difference referred to in the present invention is basically determined using the light source for photographing the photosensitive material used in the present invention.

For example, a regular X-ray film is measured using a fluorescent intensifying screen for regular X-ray film photography, and an ortho X-ray film is measured using a fluorescent intensifying screen for ortho X-ray film photography.

In addition, if a system that uses other light sources (panchromatic, infrared, etc.) appears in the future, measurements will be made using a light source that is used in combination with a photosensitive material.

In the present invention, the difference in sensitivity between the high-speed emulsion side and the low-speed emulsion side is 4% of the maximum density (not including the support density) of each side of the light-sensitive material.
It can be determined as the ratio of the reciprocal of the amount of light required to obtain a density of 0%.

In the present invention, the relative sensitivity of the emulsion surfaces on both sides of the support is:
It was obtained as follows.

The relative sensitivity of the high-sensitivity emulsion side can be determined by developing a sample exposed from the high-sensitivity emulsion side, then wiping the back (low-sensitivity) emulsion side with a proteolytic enzyme or an alkaline aqueous solution. Prepare a sample for sensitivity measurement. Sensitivity is measured by subtracting the support concentration from the maximum concentration by 0.4.
The reciprocal of the exposure amount sA required to obtain a density equal to the sum of the support density and the support density is determined. The relative sensitivity of the low-speed emulsion side is determined by developing a sample exposed from the low-speed emulsion side, then comparing the back side (
Wipe off the emulsion side (high sensitivity) in the same way to prepare a sensitivity measurement sample with an image of only the low sensitivity emulsion side, subtract the support concentration from the maximum density, multiply it by 0.4, and then add the support concentration. The reciprocal of the exposure amount sB required to obtain the density value is determined.

The light-sensitive material of the present invention has a relative sensitivity ratio of sA/sB of 2.5 to 10 between the high-speed emulsion surface and the low-speed emulsion surface determined in this way.

In the present invention, the adsorbable photographic spectral sensitizing dye refers to a cyanine or merocyanine dye that is generally used as a spectral sensitizer.

On the other hand, luminescent dyes that are non-adsorptive and easily removed by development are typified by cyanine or merocyanine dyes having at least four or more hydrophilic substituents in the molecule.

As described above, dyes having sulfonic acid or carboxylic acid as a hydrophilic group have high water solubility and are therefore substantially non-adsorbable on the silver halide surface. Further, it is a dye that can be dispersed in a high concentration in the hydrophilic colloid layer of a photosensitive material and can be easily and completely removed in a short development process.

Generally, spectral sensitization of silver halide is carried out based on the adsorption of sensitizing dyes. However, there is a limit to the amount of dye that can be adsorbed, and adsorption at or above saturation adsorption results in desensitization.

Therefore, in order to further improve spectral sensitization without causing desensitization, a luminescent dye as described above is used to convert adsorbed sensitizing dyes from non-adsorbed dye molecules without adsorbing to silver halide. The so-called light-concentration sensitization method, which uses energy transfer to molecules, is described in Japanese Patent Application Laid-open Nos. 51-117619 and 63-1.
It is disclosed in No. 38341 or No. 63-1383425.

Also, Photog, Sci, Eng of Steiger et al.
In Vol. 27, p. 59 (1983), fluorescent dyes such as cyanine dyes and xatene dyes are combined with colloidal molecules such as gelatin, which is a dispersion medium, so that these dyes absorb light energy and transfer energy. The present invention discloses a sensitization method in which the excitation effect of a dye on a silver halide surface is enhanced by optical absorption caused by the emission of light from the dye.

Specific examples of absorbable photographic spectral sensitizing dyes preferably used in the present invention are shown below, but the present invention is not limited thereto.

General formula CI) R+ Rz (xe), -+ In the formula, R1, Rz, and Rs each represent a substituted or unsubstituted alkyl group, alkenyl group, or aryl group, and at least one of R1 and R2 is a sulfoalkyl group Or take a carboxyalkyl group. ze represents an anion, Zl and Z represent a group of nonmetallic atoms necessary to complete a substituted or unsubstituted benzene ring, and n represents 1 or 2. However, when forming an inner salt, n is l.

Below - Margin Specific example of general formula CI) C21(.

2Hs l-5 General formula (II) In the formula, R+ and Rz each represent a substituted or unsubstituted alkyl group, alkenyl group, or aryl group, and at least R
Either of 1 and R2 is a sulfoalkyl group or a carboxyalkyl group. R3 represents a hydrogen atom, a lower alkyl group, or an aryl group.

XQ is an anion, zl and z2 are nonmetallic atomic groups necessary to complete the substituted or unsubstituted benzene ring, n is l or 2
represents. However, when forming an inner salt, n is 1.

Specific example of general formula [■] t-1 f-6 l-8 Uz) is C2H5Hef-9 ■ -10 General formula CnI) R,R.

In the formula, R1 and R6 are each a substituted or unsubstituted lower alkyl group, R1 and R2 are a lower alkyl group, hydroxyalkyl group, sulfoalkyl group, or carboxyalkyl group, Xe is an anion, and Zl and z2 are substituted or unsubstituted lower alkyl groups. A nonmetallic atomic group necessary to complete the benzene ring, n represents 1 or 2. However, when forming an inner salt, n is l.

Specific example 1 of general formula (III) [[-3 C2H! CzHs (CHz)asO3Na (CF!ri4503'''
lI[[-4 C2H, C2H5 Next, specific examples of luminescent photographic dyes preferably used in the present invention will be shown, but the present invention is not limited thereto.

General formula (IV) R.R.

In the formula, X and X may be the same or different and represent an oxygen atom or a sulfur atom, and R and R represent an alkyl group, a sulfoalkyl group, or a carboxyalkyl group.

R2 is hydrogen atom, halogen atom, -803 group, -C00
M group, O(CHz) Im SO3M group, -N
(CH2CH2SO,M)2 groups, -Sow(CH2)l
Represents an lsOxM group, a CONH(CH2)11503M group, -So, NH(CH), a msO,M group.

R1 is a hydrogen atom, a halogen atom, -So3M group, -C0
Represents 0M group. M represents a hydrogen atom or an alkali metal atom.

R4 represents a hydrogen atom or a methyl group. m represents 2-4, and n represents 0 or 1-3.

General formula [v] In the formula, R represents a sulfoalkyl group and R1 represents a sulfoalkyl group or a carboxyalkyl group. R2 represents a hydrogen atom, a trifluoromethyl group, a sulfoalkyl group or a C00M group. M represents a hydrogen atom or an alkali metal atom. R
1 represents a hydrogen atom, a halogen atom or a sulfoalkyl group, R4 represents a hydrogen atom or a methyl group, and B2 represents 1-3.

General formula (VI) 1? .

In the formula, X represents an oxygen atom or a sulfur atom. R represents a sulfoalkyl group, and R8 represents an alkyl group, a sulfoalkyl group, or a carboxyalkyl group.

R2 is a sulfoalkyl group or a carboxyalkyl group,
R3 represents a hydrogen atom or a -C00M group, and R4 represents a hydrogen atom or a trifluoromethyl group, a sulfoalkyl group, or a carboxyalkyl group.

R5 is -COOM group, -503M group, O (CHz)
8503M group, -(CB2)8503M group. M is a hydrogen atom or an alkali metal atom, m represents 1 to 4, and n
, represents 1 to 3.

General formula [■] In the formula, R and R1 may be the same or different and represent an alkyl group, a sulfoalkyl group, or a carboxyalkyl group, and R2 is a hydrogen atom, a -503M group, a -C00M group, a sulfoalkyl group, The carboxyalkyl group R1 represents a hydrogen atom, a halogen atom or a -S 03 M group. M represents a hydrogen atom or an alkali metal atom, and n is O or 1-
Represents 2.

General formula [■] R.R.

In the formula, X and X may be the same or different and are oxygen atoms,
Represents a sulfur atom or -N-CH, group.

'R, R, represent an alkyl group, a sulfoalkyl group, a carboxyalkyl group, R2, R3 are ~So3M group, -
It represents a C00M group, and M represents a hydrogen atom or an alkali metal atom. R4 represents a hydrogen atom or a methyl group, and n is 0
Or represents 1-2.

General formula (II) In the formula, X represents a sulfur atom or an oxygen atom, R9R1 represents a sulfoalkyl group, R2 and R are a
Represents C00M group, O(CH: )m S 03 M group. M represents a hydrogen atom or an alkali metal atom, m is 1
- represents 4.

The general formulas [■] to [■] preferably used in the present invention are as follows:
] The present invention is not limited to these specific examples.

V-1 v-2 V-3 *5O2(CH2)zSOlNa (CH2)2503'a (+
,,t12J2:>LJ3NaV-5 * (CHz)-5OJa v-4 CH2COOK ■ ■-3 CH,COONa Spirit CH2COONa (CH2)2SOxNa ■-l ■-2 ■-3 ■-4 ■-5 (CH2)2COO '(CH2)2cO
ONa ■-1 ■-2 ■-3 ■-4 ■-5 Other pigments include the following.

l-1 (CHz)aSOx-(cH2)4so3Naf-2 I-3 I-4 (CHz)asO3e The above-mentioned cyanine dyes and luminescent dyes according to the present invention are known compounds, such as those described in " The C
yanine Dyes and Re1ated C
compounds”Interscience, Ne
York (1964) or can be synthesized according to it.

The above adsorbed cyanine dye and luminescent dye according to the present invention may be added at any time during the manufacturing process of silver halide photographic materials, but preferably from the time of silver halide grain formation to after the completion of chemical ripening. Any suitable time is fine.

The effects of the present invention are best achieved by adding the luminescent dye to a light-sensitive silver halide emulsion layer containing an adsorbable spectral sensitizing dye.

In the case of adsorption type spectral sensitizing dye, the amount added is 1 silver halide.
An amount sufficient to increase the sensitivity may be used in the range of 1 x 10-' to 5 x 10-'' moles per mole, preferably 3 x 10 to 2.5 x to-' moles.

The amount of one luminescent dye added is 2.0-3 to the hydrophilic colloid layer of the silver halide photographic light-sensitive material according to the present invention.
0rnmo (1/dm”, more preferably 5.0-
200-2 O/dm".

The adsorption type and luminescent anine dyes according to the present invention can be used singly or in combination with water or a hydrophilic solvent such as methanol or ethanol.
It may be added after being dissolved.

For the total amount of silver halide in the high-speed layer of the light-sensitive material of the present invention, it is necessary to use silver halide grains with a larger average grain size than in the low-speed layer, and to form a density as high as possible. Therefore, it is necessary to increase the amount of silver halide deposited on the high-sensitivity layer side.

The transmittance of incident (exposure) light from the high-sensitivity surface to the low-sensitivity surface of the photosensitive material of the present invention is 12% or more, more preferably 20%.
It is in the range of ~90%. This is because if the transmittance is too low, the amount of light exposed from the high-sensitivity emulsion surface reaching the low-sensitivity surface will be small, making it impossible to efficiently expose the low-sensitivity emulsion surface.

The transmittance from the high sensitivity surface to the low sensitivity surface of the photosensitive material of the present invention is the relative sensitivity (s) of the low sensitivity surface when exposed from the high sensitivity surface.
B') and the relative sensitivity (sB) of the low-sensitivity surface when exposed from the low-sensitivity surface.

(sB'/sB)>0.12 is the photosensitive material of the present invention.

Relative sensitivity is determined as the reciprocal of the exposure amount required to obtain a density equal to the value obtained by subtracting the support density from the maximum density of the low-speed surface, multiplied by 0.4, and then adding the support density.

As the light source for determining the relative sensitivity of the sample of the present invention, it is preferable to use a light source that is optimal for exposing each photosensitive material.

For example, if you use regular X-ray film for direct photography,
If it is a blue light-emitting intensifying screen (e.g. NR-160 sold by Konica Co., Ltd.) that uses CaWO as the phosphor, and if it is an ortho X-ray film for direct photography, GdO□ is used as the phosphor.
S: Green emitting intensifying screen using Tb (e.g. 5RO
-160 sold by Konica [stock]), 0.020 to 0
．． It is preferable to use an exposure time of 20 seconds. If it is a film for CRT photography, it is preferable to obtain the time in the range of 0.5 to 2 seconds using a CRT using P,45 phosphor.

If the film records laser light, it is preferable to use the laser light used to expose the film. T
I If it is a film for indirect photography, ■! If the film is for indirect photography using a mirror camera, it is preferable to determine the light emission from the secondary phosphor screen.

In order to achieve the object of the present invention, the total amount of silver halide in the high-speed layer is 1.2 times or more, preferably 1.3 times or more, as compared to the low-speed layer. is preferred. The silver content ratio of both layers is preferably 1:5 or less. If it exceeds this range, the advantage of providing silver halide on both sides of a photosensitive material intended for single-sided exposure, as in the present invention, will be diminished.

A further feature of the present invention is that the light-sensitive material according to the present invention is exposed only from one side. In this case, the film may be placed on either the front or the back side with respect to the X-ray incident side, but preferably the surface of the high-sensitivity layer is on the incident side.

In cases where the density of information from the photograph is concentrated below 2.0, such as in medical black-and-white photographs, the depiction of low-density areas is essentially done on the side facing the light source (high-sensitivity emulsion side). This method is very effective as a means of preventing deterioration in the sharpness of photographs during photographing and observation.

When using a fluorescent intensifying screen, it may be set on either the front or back side of the film, but it is preferable to set the fluorescent intensifying screen on the high-sensitivity emulsion layer side to better achieve the objective effects of the present invention.

As mentioned above, the silver halide photographic material according to the present invention has a silver halide emulsion layer coated on both sides of the support, and has the characteristic that the sensitivity of the emulsion differs between the front and back sides. .

The emulsion used in the silver halide photographic light-sensitive material of the present invention may be any silver halide such as silver iodobromide, silver iodochloride, silver iodochlorobromide, etc., but it is said that particularly high sensitivity can be obtained. From this point of view, silver iodobromide is preferred.

Silver halide grains in photographic emulsions are cubic, octahedral, 1
A crystal type that is entirely isotropically grown such as a tetrahedron, a polyhedral crystal type such as a spherical shape, a crystal type that is composed of twin crystals with planar defects, or a mixed or composite type thereof. Good too. The grain size of these silver halide grains may range from fine grains of 0.1 μm or less to large grains of up to 20 μm.

The emulsion used in the silver halide photographic material of the present invention can be produced by a known method. For example, Research Disclosure (RD) No. 17643 (December 1978) - pages 22-23, 1. Emulsion manufacturing method (En+u
l s 1onPreparation and ty
pes) and (RD) No. 18716 (1979
It can be prepared by the method described on page 648 (November 2013).

The emulsion of the silver halide photographic light-sensitive material according to the present invention is described, for example, in "The theory o" by T. H. James.
f thephotographic process
"4th edition, published by Macmillan (1977')
Pages 38-104 I Methods Described by G. F. Dauffi
“Photographic Emulsion Chemistry” by n.
eo+ulsionChemistry”, Focal
Press (1966), Glafkid, P.
“Physics and Chemistry of Photography” by Chimie etphy
sique photography”Paul
Published by Mante1 (1967), V, L, Zeli
"Manufacture and Coating of Photographic Emulsions" by Kman et al.
g and coating photography
cemulsion HFocal press (1
964) and others.

That is, solution conditions such as neutral method, acidic method, ammonia method, etc.
It can be produced using particle preparation conditions such as forward mixing method, back mixing method, double jet method, Chondral double jet method, conversion method, core/shell method, and combination methods thereof.

A preferred embodiment of the present invention is a monodispersed emulsion in which silver iodide is localized inside the grains.

Examples of silver halide emulsions preferably used in the present invention include JP-A-59-177535 and JP-A-61-802.
No. 237, No. 61-132943, No. 63-4975
1 and Japanese Patent Application No. 63-238225. The crystal habits are cubic, tetradecahedral, octahedral, and the intermediate (1, 1,
1) plane and (1,0,0) plane may be arbitrarily mixed.

The term "monodispersed emulsion" as used herein means at least 9 particles in number or weight when the average particle diameter is measured by a conventional method, for example.
5% of the grains are silver halide grains within ±40%, preferably within ±30% of the average grain size. The grain size distribution of silver halide may be either a monodisperse emulsion with a narrow distribution or a polydisperse emulsion with a wide distribution.

The crystal structure of silver halide may have different silver halide compositions inside and outside.

The emulsion as a preferred embodiment of the present invention is a core/shell type monodisperse emulsion having a clear two-layer structure consisting of a high iodine core portion and a low iodine shell layer.

The silver iodide content of the high iodide portion of the present invention is 20 to 40 mol%, particularly preferably 20 to 30 mol%.

Methods for producing such monodisperse emulsions are known, for example, J. Ph.
ot, Sic, pp. 12.242-251 (1963)
, JP-A-48-36890, JP-A-52-16364,
No. 55-142329, No. 58-49938, British Patent No. 1,413.748, U.S. Patent No. 3,574,628
No. 3,655.394.

As the above-mentioned monodisperse emulsion, an emulsion in which grains are grown by using seed crystals and supplying silver ions and halide ions using the seed crystals as growth nuclei is particularly preferred. In addition, as a method for obtaining a core/shell emulsion, for example, British Patent 1
, 027.146, U.S. Pat. No. 3,505,068,
This is described in detail in publications such as No. 4,444,877 and Japanese Unexamined Patent Publication No. 14331/1983.

The silver halide emulsion used in the present invention may be tabular grains having an aspect ratio of 4 or more and less than 30.

The advantages of such tabular grains include improved spectral sensitization efficiency and improved image graininess and sharpness, as described in British Patent No. 2.112.157 and US Pat. No. 4,4.
39.520, 4,433.048, 4,41
No. 4.310, No. 4,434,226, JP-A-58-
No. 113927, No. 58-127921, No. 63-1
No. 38342, No. 63-284272, No. 63-30
No. 5343, etc., and an emulsion can be prepared by the method described in the publication.

The above-mentioned emulsion may be a surface latent image type that forms a latent image on the grain surface, an internal latent image type that forms a latent image inside the grain, or a type that forms a latent image on the surface and inside the grain. Good too. These emulsions may use cadmium salts, lead salts, zinc salts, thallium salts, iridium salts or complex salts thereof, rhodium salts or complex salts thereof, iron salts or complex salts thereof, etc. at the stage of physical ripening or grain preparation. In order to remove soluble salts, the emulsion may be washed with water such as the Nordel water washing method and the flocculene condensation method. Preferred water washing methods include, for example, the method using an aromatic hydrocarbon aldehyde resin containing a sulfo group as described in Japanese Patent Publication No. 35-16086, or the method described in Japanese Patent Publication No. 16086
Agglomerated polymer agent example G 3 described in No. 3-158644,
A particularly preferred desalting method is a method using G 8 or the like.

Various photographic additives can be used in the emulsion according to the present invention in the steps before and after physical ripening or chemical ripening.

Examples of known additives include Research Disk A-
Examples include compounds described in Di+ -No. 17643 (December 1978) and No. 18716 (November 1979). Compound types and additives shown in these two research disclosures RD17643 RD-18716
Page Classification Page Classification Chemical Sensitizer 23II [648-Upper Right Sensitizer Dye 231V648Right-649
Left development accelerator 29
// 11 colors anti-staining agent 25 ■ 6
50 Left-Right Image Stabilizer 25 ■ Ultraviolet Absorber 25-26 ■ 649 Right-650 Left Filter Dye 11 11 Brightening Agent 24 V Hard
Curing agent 26X651 left coating aid
Agent 26-27 XI 650 Right Surfactant 26-27... 650 Right Plasticizer 27 ■〃
Sliding agent Static inhibitor 27 u tt Matting agent 28 Page and 64 of RD-18716
List the items listed in the left column of page 7.

Suitable supports include plastic films, and the surfaces of these supports may generally be provided with an undercoat layer or subjected to corona discharge, ultraviolet irradiation, etc. in order to improve the adhesion of the coating layer. The emulsion according to the present invention can then be coated on both sides of the support thus treated.

When applying the present invention to medical X-ray radiography,
For example, a fluorescent intensifying screen whose main component is a phosphor that generates near-ultraviolet light or visible light when exposed to penetrating radiation is used. It is desirable to expose this material in close contact with both surfaces of a light-sensitive material prepared by coating both surfaces with the emulsion of the present invention.

The penetrating radiation herein refers to high-energy electromagnetic waves, and means X-rays and gamma rays.

〔Example〕

Examples of the present invention will be described below. However, it goes without saying that the present invention is not limited to the examples described below.

Example 1 (1) Preparation of monodisperse grains Monodisperse grains of silver iodobromide containing 2.0 mol% of silver iodide with an average grain size of 0.2 μm are used as cores, and iodine containing 30 mol% of silver iodide is used as the nucleus. Silver bromide was grown at pH 94 and pAg 7.8, and then equal moles of potassium bromide and silver nitrate were added at pH 8.2 and pAg 9.1 to grow silver iodobromide with an average silver iodide content of 2.2 mol%. The average particle size to become particles is 0.375 μm (■-1
).

0.64gm (■-2), 1.22gm (■-3
), 0.88 μm (■-4), four types of monodisperse emulsion grains were prepared. The emulsion was desalted to remove excess salts using a conventional flocculation method. That is, the temperature was maintained at 40°C, and a formalin condensate of sodium naphthalene sulfonate and an aqueous solution of magnesium sulfate were added to cause coagulation, and the supernatant liquid was removed.

The four types of particle sizes obtained had good monodispersity with S/<0.16.

(2) Preparation of tabular grains A 1.5% gelatin solution 5.5a containing 0.17 mol of potassium bromide was stirred at 80° C. and pH 5.7, and then mixed with 2.5 mol of potassium bromide by the double jet method. 1 mole and the equivalent of 2.0 moles of silver nitrate were added in solution over a period of 3 minutes. pBr was maintained at 0.8. (0.53% of the total silver nitrate used was consumed.) The potassium bromide solution addition was stopped and the silver nitrate solution was continued to be added for 4.6 minutes. (Consuming 8.6% of all silver nitrate used.)
Then, potassium bromide solution and silver nitrate solution were added at the same time to 12
Added for 1 minute. During this period, pBr was maintained at 1.15, and the addition flow rate was accelerated so that the flow rate at the end was 2.3 times that at the start. (43.6% of the total silver nitrate used was consumed.) The potassium bromide solution addition was stopped and the silver nitrate solution was added for 1 minute. (Consuming 4.7% of the total silver nitrate used.) A 2.1 molar solution of potassium bromide containing 0.55 molar potassium iodide was added over 12.0 minutes along with the silver nitrate solution. During this time, the pBr was maintained at 1.7 and the flow rate was accelerated to be 1.5 times the starting rate upon completion. (35.9% of the total silver nitrate used was consumed.) To this emulsion was added 1.5 g of sodium thiocyanate, 1 mole of Ag, and held for 25 minutes. A solution of 0.60 mol of potassium iodide and silver nitrate was prepared by double jet method I at a constant flow rate for about 5 minutes until the pBr was 3.0.
Added until reaching . (used t; about 6.6 of total silver nitrate
Consume %. ) The total amount of silver nitrate consumed was approximately 11 moles. In this way, an emulsion (2) containing tabular silver iodobromide grains with an average grain diameter of 1.80 itm and an aspect ratio of about 9:1 was prepared. In these grains, tabular grains accounted for 80% or more of the total projected area of the silver iodobromide grains.

Preparation, treatment, and evaluation of samples Each of the obtained silver halide grains (■-1, ■-2, ■-3, ■-4, and ■) had a volume per mole of silver of 500.
Add pure water so that +++<1 and then heat to 55°C.
Adsorptive sensitizing dyes as shown in Table 2 below were added to each grain in an optimum amount within the range of 1 mg to 1 g per mole of silver oxide.

Then, after 10 minutes, appropriate amounts of ammonium thiocyanate, chloroauric acid, and hypo were added to start chemical ripening. At this time, the pH was 6.15 and the silver potential was 50mV.

15 minutes before the end of chemical ripening (70 minutes after the start of chemical ripening), 200 mg of potassium iodide was added per mole of silver, and after 5 minutes, 10% (wt/vol) acetic acid was added to adjust the pH to 5.
．． 6 and maintain its I) El value for 5 minutes, then add a 0.5% (wt/vol) solution of potassium hydroxide to return pi( to 6.I5, then 4-hydroxy-6-
Methyl-1,3,3a,7-chitrazaindene was added to complete the chemical ripening.

■-1, ■-2, ■-3, ■-4 and ■ of the obtained particles
After mixing as shown in Table 1, exemplary compounds of the luminescent dye according to the present invention were added as shown in Table 2. Next, add the emulsion additives listed below to prepare a liquid.

The pH after preparing the photographic emulsion coating solution was adjusted to 6.40, and the silver potential was adjusted to 74 mV (35° C.) using a sodium carbonate and potassium bromide solution.

Using this emulsion coating solution, samples were prepared as follows.

That is, the amount of gelatin in the photographic emulsion layer was 2-0 g/m'' on both the high-speed emulsion side and the low-speed emulsion side, and the amount of silver halide grains was adjusted as shown in Table 1 in terms of silver. In addition, a protective layer solution was prepared using the additive described below, so that the protective layer had a gelatin loading of 1.15 g/m''.
Two slide hopper type coaters were used to simultaneously coat both sides of the support at a speed of 80 m/min and dry in 2 minutes and 20 seconds to obtain a sample. As a support, glycidyl methacrylate 5Qvt%, methyl acrylate 1Qwt%
A copolymer aqueous dispersion obtained by diluting a copolymer consisting of three monomers of 40 wt % and butyl methacrylate to a concentration of 19 wt % was applied as an undercoat liquid 1
A Tahouriethylene terephthalate film base was used, colored blue to a density of 0.15 for 75 μm X-ray film.

Further, the additives used in the emulsion liquid (photosensitive silver halide coating liquid) are as follows. The amount added is expressed as the amount per mole of 110 silver gemide.

1.1-dimethylol-1-bromo-1-nitromethane 70n+gt-butyl-catechol 400mg polyvinylpyrrolidone (molecular weight 10,000) 1.0g styrene-maleic anhydride copolymer 2.5g nitrophenyl-
Triphenylphosphonium chloride 50mg1.
Ammonium 3-hydroxybenzene-4-sulfonate 4g Sodium 2-mercaptobenzimidazole-5-sulfonate 1.5mg
H Dextran (average molecular weight 60,000) 0-6g1-
Phenyl-5-mercaptotetrazole 15 mg Sodium polyacrylate (average molecular weight 36,000) 2.5 g Additives used in the protective layer solution are as follows. The amount added is shown in the amount per 112 coating liquid.

Lime-treated inert gelatin 68g Acid-treated gelatin 2g Polymethyl methacrylate, matting agent with area average particle size 3.5μm 1.1g
Matting agent with silicon dioxide particle area average particle size 1.2μm 0.5g
Colloidal silica (manufactured by Ludox A Dupont) 30gC
, HzsCONH(CHzCHzO)sH2,Og (dye emulsion dispersion) 0.4 g The dye emulsion dispersion was prepared as follows.

10 kg of each of the above dyes was weighed and dissolved in a solvent consisting of tricresyl phosphate 12Q and ethyl acetate 85Q at 55°C. This is called an oil-based solution. On the other hand, 1.35 kg of anionic surfactant (AS below)
, 9.3% Zey'f aqueous solution dissolved at 45°C27
0mQ was prepared. This is called an aqueous solution.

(AS) The above oil-based and water-based solutions were placed in a dispersion vessel and dispersed under reduced pressure under high speed rotation.

The following additives and water were added to the resulting dispersion to give a total weight of 240 kg.

Phenol (2.5% aqueous solution) 1612
r The sensitivity of each surface of the obtained sample was determined using a fluorescent intensifying screen KO-250.
(manufactured by Konica Corp.) was photographed from the high-sensitivity emulsion layer side using the single back method using only the back surface.

For exposure, X-rays were irradiated for 0.05 seconds at a tube voltage of 90 KVP and 20 mA, and a sensitometric curve was created using the distance method to determine sensitivity, maximum density, and gamma.

The development is done using an automatic processor 5RX-501 (Konica C stock).
using a developer with the following composition, the developing temperature was 35°C, the fixing temperature was 33°C, and the washing water was 18°C at a flow rate of 1.5ff per minute.
i, and the entire process was run in 45 seconds mode.

The relative sensitivity and system sensitivity in Table 2 are calculated as the reciprocal of the X-ray dose required to obtain the concentration obtained by subtracting the support concentration from the maximum concentration, multiplied by 0.4, and adding the support concentration. It is expressed as relative sensitivity when sample No. 1 is set as 100.

However, since Samples No. 1 and 1 had the same emulsion constituent layers as a normal double-sided X-ray film, they were normally exposed using a fluorescent intensifying screen on both sides.

In addition, the following evaluation was performed on the sample after coating and drying.

As an evaluation of the image quality of each sample No. 1 to 14, sharpness is evaluated using a photographed sample.

Fluorescent intensifying screen KO only on high-sensitivity emulsion side using single back method
-250 and a tube voltage of 90KVP. The processing was the same as the sensitometry described above (same automatic developing machine,
(processing agent, processing temperature, processing time).

Sharpness was evaluated using Functist Chart 5M55853 (manufactured by Konica Medical Co., Ltd.) under the same tube voltage, intensifying screen, and processing conditions as the actual photograph.

Each sample was exposed to light such that the average density of shading determined by the Funkist chart was 0.8.0.02.

Developer composition Potassium sulfite 60.0g Hydroquinone 25.0g 1-phenyl-3-pyrazolidone 1.5g Hou @ l O, Og
Potassium hydroxide 23.0g Triethylene glycol 17.5g 5-Methylbenztriazole 0.04g 5-nitropenzimidazole 0.11g 1-7 enyl-5-mercaptotetrazole 0.015g Glutaraldehyde bisulfite 8.0g Glacial acetic acid
16.0g potassium bromide
Add 4.0g water to make 1Q.

A: It is possible to identify up to 10LP/mm with a magnifying glass.

B: Up to 8LP/mm can be identified with a magnifying glass.

C: Up to 6LP/mm can be identified with a magnifying glass.

D: Up to 5LP/mm can be identified with a magnifying glass.

E: Up to 4LP/mm can be identified with a magnifying glass.

In the above, A means the best, and E means not the best.

The results obtained are shown in Table 2 below.

In addition, for the drying test, the sample was placed in a Konica Corporation automatic processor 5.
Processing was performed using RX-501 in 45 second processing mode. The temperature at the location where the automatic processor was installed was 25° C. and the relative humidity was 62%. The drying air temperature setting of the automatic developing machine is 43°.
It was set as C.

However, when evaluating drying properties, in order to confirm practical drying properties, the processing machine and processing agent were used under the same conditions as in the sensitivity measurement described above, but the atmosphere at the place where the automatic processing machine was installed was set at a temperature of 25°C. The dryness of each sample was confirmed at a relative humidity of 80%.

The drying property was evaluated in five stages according to the following criteria.

Dryness evaluation criteria ■: Completely dry, sample is warm A2: Completely dry, sample is cold B3: Slightly damp (
173 or less) C4, damp (273 or less) D5, damp (more than 2/3)
EAlso, evaluation of residual silver was carried out as follows.

The film prepared above was developed without being exposed to light to obtain a sample for evaluation of residual silver. Evaluation of residual silver was performed by the following method.

Add one drop of a 2.6810-"moQ/Q aqueous solution of sodium sulfide as a residual silver evaluation solution onto the above film for residual silver evaluation, let it stand for 3 minutes, wipe off the liquid well, and store at room temperature for 15 minutes. I left it for a while.

Then, using a PDA-135 type densitometer (manufactured by Konica Corporation), measure the transmission density of blue light in the area where the residual silver evaluation solution was dropped and the area where it was not dropped, and use the difference to determine the residual silver. It was used as a guideline. The greater this difference, the higher the residual silver concentration in the film after processing. The results obtained are shown in Table 2 below.

As is clear from Table 2, the samples according to the present invention had improved sharpness without decreasing sensitivity, produced less residual silver due to insufficient fixing during rapid processing, and had good drying properties.

〔Effect of the invention〕

According to the present invention, a silver halide photographic light-sensitive material has been obtained which has greatly improved image sharpness and has rapid processing properties without reducing photosensitivity.

According to the present invention, it was possible to provide an improved single-sided X-ray exposure system that performs X-ray exposure only from one side and performs rapid development processing.

Claims (1)

[Claims] A silver halide photographic material having at least one light-sensitive silver halide emulsion layer on both sides of a transparent support,
The sensitivity of the emulsion side on one side is 2.5 to 10.0 times higher than the sensitivity of the emulsion side on the other side, and the total amount of silver halide on the high-speed emulsion side is In a silver halide photographic light-sensitive material whose density is 1.2 to 4.0 times larger than that on the other side, the silver halide grains have at least one adsorbable photographic spectral sensitizing dye and a non-adsorbable photographic spectral sensitizing dye. A silver halide photographic material for X-rays, characterized in that it contains in combination with at least one luminescent dye that is easily removed by development.