JP2838564B2 - Silver halide photographic material - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a silver halide photographic light-sensitive material which does not impair the photographic performance of an infrared sensor used in an automatic film processing machine or the like. is there.

[Background of the Invention]

Recently, the processing time of silver halide photographic light-sensitive materials has been increasing in accordance with the needs of users with an increase in film consumption, and the progress has been remarkable especially in the field of medical films.

In many cases, an infrared sensor is used for detecting a film in an automatic developing machine or a daylight device which is a device of a rapid processing system. This is because infrared rays are compatible with the photosensitive material and efficient detection can be obtained.

For the purpose of speeding up the operation, safety and labor saving of X-ray films, so-called daylight machines capable of refilling and developing films in bright rooms are increasing. In general, an infrared sensor having a sensitivity in a wavelength range of 700 nm to 960 nm is used in the daylight machine in order to identify the presence / absence of a film and multiple transport.

On the other hand, in the case of photosensitive materials, especially X-ray films for direct photography, many technical efforts have been made to meet the demand for higher sensitivity and higher image quality, and core / shell type silver iodobromide grains containing high silver iodide have been developed. There has been proposed a silver halide light-sensitive material having an emulsion layer. However, the core / shell type silver iodobromide emulsion obtained by using the conventional seed emulsion of the crystal nucleus system is slightly susceptible to heat fog and pressure fog, has poor adsorption of the sensitizing dye, and tends to be softly inclined. Further, there is a defect that the safety light fog is large, which greatly impairs the processing operation and impairs the commercial value. In order to eliminate this drawback, the core / shell type silver iodobromide emulsion grains are suitable for the grains grown by enclosing a reduced shell layer inside the grains. However, it has been found that a silver halide photographic material using these grains has a serious defect of causing fogging due to the light of the infrared sensor.

[Object of the invention]

Accordingly, a first object of the present invention is to provide a silver halide photographic material having high sensitivity and excellent image quality. Another object of the present invention is to provide an X-ray film which has high sensitivity and does not cause fog even with light from an infrared sensor of an automatic processor.

[Configuration of the invention]

As a result of intensive studies, the present inventors have found that these objects are achieved as follows, and have accomplished the present invention.

That is, at least one surface of the support has at least one emulsion layer containing photosensitive silver halide grains which have been subjected to chemical sensitization after growing by enclosing a shell layer subjected to a reduction treatment inside the grains, and This has been attained by a silver halide photographic material characterized in that at least one of the constituent layers contains an infrared absorbing dye.

 Hereinafter, the present invention will be described more specifically.

The silver halide emulsion of the present invention is preferably a monodisperse emulsion, and particularly preferably a silver halide emulsion containing 50% by weight or more of silver halide grains within a grain size range of ± 20% around the average grain size d. Used.

In the silver halide emulsion of the present invention, silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodobromide, etc., have an arbitrary halogen composition, but silver iodobromide is preferable in terms of high sensitivity. The iodine content is preferably at most 20 mol%, more preferably at most 15 mol%, particularly preferably at most 10 mol%.

Silver chloride may be contained as long as the effects of the present invention are not impaired.

In the silver halide emulsion of the present invention, the halogen composition may be uniform within the grains or silver iodide may be localized, but those localized in the center are preferably used. .

As is well known, the core / shell type emulsion grains of the present invention are prepared by forming a monodisperse seed emulsion as a core and forming at least two or more shell layers thereon. At this time, any shell layer other than the outermost shell layer is subjected to a reduction treatment, and the outer shell layer is further grown as it is.

The reduction treatment according to the present invention is preferably performed on the surface of the inner shell layer that is multi-layered, for example, on the surface of seed emulsion grains or on the surface of the shell layer when growth is stopped, from the viewpoint of effect control.

As a method of the reduction treatment, there is a method of passing a silver ion excess state or addition of a reducing compound.

How much silver ion is excessive depends on the type of silver halide, but at 30 to 80 ° C. and pH 5 to 11, pAg1 to
6 is preferably 2 to 4, 10 to 200 minutes.

The reducing compound may be any of inorganic and organic compounds, and specific examples thereof will be given below.

The amounts of these compounds to be added vary depending on the reducibility, the type of silver halide and the solution conditions, and are determined experimentally.

: Specific compounds Thiourea dioxide, stannous chloride, hydrazine, polyamines such as diethylenetriamine, and sulfite are preferred.

Next, the infrared absorbing dye used in the present invention is 700 to 960
Dyes that absorb light in the wavelength region of nm, preferably in the range of 750 to 920 nm, are preferably used.

In the embodiments of the present invention, examples of the dyes more preferably used include water-soluble dyes having a hydrophilic group, such as tricarbocyanines and indoanilines.

Metal complex salt type dyes are also preferably used in the present invention, and examples thereof include iron chelate type and dithiolate nickel type dyes.

The dye is a known compound, for example, JP-A-62-1234
No. 54, EP-251,282, No. 288,076, DP-1,152,609
No., JP-A-50-100166, JP-A-62-3250, JP-A-62-181381
No. 61-70503, No. 61-32003, No. 61-11704,
It can be synthesized according to the method described in the official gazette of JP-A-61-80106 or the like, or according to it.

Next, examples of the dye used in the present invention include a dye represented by the following general formula (I).

[A]: represents a cation necessary for neutralizing the metal complex, and m represents 1 or 2.

M represents nickel, cobalt, copper, platinum, or palladium.

Z represents a group of non-metallic atoms necessary to form a 5- or 6-membered ring.

Preferably R _{1 to} R ₈ : hydrogen atom, halogen atom or direct or 2
Represents an alkyl group or an aryl group bonded to the benzene ring via a valent linking group, which may be the same or different from each other.

In the compound represented by the general formula (I), [A]
Examples of the inorganic cations among the cations represented by are alkali metals (eg, Li, Na, K, etc.), alkalis ± like metals (Mg, Ca, Ba, etc.) and NH ₄ ⁺ .

Examples of the organic cation include a quaternary ammonium ion and a quaternary phosphonium ion.

Among the above cations, preferred are those represented by the following general formula (II)
-A), (II-b), (II-c), (II-d) or (II-e).

Where R ¹ , R ² , R ³ , R ⁴ , R ⁵ , R ⁶ , R ⁷ , R ⁸ , R ⁹ , R ¹⁰ , R
¹¹ and R ¹² are each alkyl of 1 to 20 carbon atoms (including those having a substituent.), Or C 6 -C (including those having a substituent.) An aryl group of 14 represents, Z ¹ and Z ² represents a non-metallic atomic group which forms a 5- or 6-membered ring by bonding to a nitrogen or phosphorus atom in each formula.

Examples of such an alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, an n-butyl group, an iso-amyl group, an n-dodecyl group and an n-octadecyl group. Examples of the aryl group having 6 to 14 carbon atoms include a phenyl group, a tolyl group and an α-naphthyl group.

These alkyl or aryl groups include a cyano group, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms (for example, a methyl group, an ethyl group, an n-butyl group, an n-octyl group, etc.),
An aryl group having 6 to 14 carbon atoms (for example, a phenyl group, a tolyl group, an α-naphthyl group, etc.);
20 acyloxy groups (eg, acetoxy group, benzoyloxy group, p-methoxybenzoyloxy group, etc.), alkoxy groups having 1 to 6 carbon atoms (eg, methoxy group, ethoxy group, propoxy group, butoxy group, etc.), aryloxy group (eg, , Phenoxy group, toloxy group, etc.), aralkyl group (for example, benzyl group, phenethyl group or anisyl group, etc.), alkoxycarbonyl group (for example, methoxycarbonyl group, ethoxycarbonyl group, n-butoxycarbonyl group, etc.),
Aryloxycarbonyl group (eg, phenoxycarbonyl group, toloxycarbonyl group, etc.), acyl group (eg, acetyl group, benzoyl group, etc.), acylamino group (eg, acetylamino group, benzoylamino group, etc.), carbamoyl group (eg, , N-ethylcarbamoyl group, N-phenylcarbamoyl group, etc.),
Alkylsulfonylamino group (eg, methylsulfonylamino group, phenylsulfonylamino group, etc.), sulfamoyl group (eg, N-ethylsulfamoyl group, N-phenylsulfamoyl group, etc.), sulfonyl group (eg, mesyl group, For example, a tosyl group).

Z ¹ and Z ² each represent a non-metallic atomic group necessary for forming a 5- or 6-membered ring as described above. Examples of the 5- or 6-membered ring include a pyridine ring, an imidazole ring, a pyrrole ring, a 2-pyrroline ring, a pyrrolidine ring, a piperidine ring, a pyrazole ring, a pyrazoline ring, and an imidazoline ring. Examples of the cation represented by the general formula (II-b) include a dodecylpyridinium group, a hexadecylpyridinium group, and a dodecylimidazolium group. Examples of the cation represented by the general formula (II-c) include N-ethyl-N
-Hexadecylpiperidinium group, N-ethyl-N-dodecylpyrazolidinium group and the like.

The above general formulas (II-a), (II-b), (II-c),
Among the cations represented by (II-d) and (II-e), those which are particularly preferably used in the present invention are (II-a) in view of availability of production raw materials and production cost, (II-
b), (II-d) and (II-e).

The type of the cation [A] affects the solubility of the compounds represented by the general formulas (I) and (II) in an organic solvent.

Generally, when the substituent bonded to the quaternary heteroatom is an alkyl group, the longer the chain length, the higher the solubility. Particularly, in the case of tetraalkyl-substituted ammonium or phosphonium, this tendency is remarkable. The cation having a total of 17 or more gives a high solubility, and in the case of a phosphonium cation, a cation having a total of 4 or more gives a high solubility.

In the compound represented by the general formula (I), M ₁ or
M ₂ is preferably nickel, cobalt, copper, palladium, and platinum in the preferred order.

The compound represented by the general formula (I) can be synthesized as follows.

The compound of the general formula (a) (m = 2) is obtained by first reacting disodium-1,3-dithiol-2-thione-4,5-dithiolate obtained by reacting carbon disulfide with sodium to form a zinc complex. The benzoyl chloride is reacted to form a bisbenzoylthio form. It is obtained by decomposing it with an alkali and then reacting with a metal salt.

The compound of the general formula (a) (m = 1) can be obtained by oxidizing the complex (m = 2) obtained above with an appropriate oxidizing agent.

The compound of the general formula (b) (n = 2) is prepared by first reacting carbon disulfide with sodium to obtain gindium-1,3
Dithiol-2-thione-4,5-dithiolate to about 1
Heat to 30 ° C. to isomerize to disodium-1,2-dithiol-3-thione-4,5-dithiolate.

This is made into a zinc complex, which is reacted with benzoyl chloride to form a bisbenzoylthio form. It is obtained by decomposing it with an alkali and then reacting with a metal salt.

The compound of the general formula (II) (n = 1) can be obtained by oxidizing the complex (n = 2) obtained above with an appropriate oxidizing agent.

The 1,3-dithiol-2-thione-4,5-dithiolate anion, which is an intermediate for obtaining the compound of the general formula (a) or (b), can be used in addition to the above-described reduction method using Na, It can also be obtained by chemical reduction.

The above compound can be synthesized by the method described in JP-A-61-26686 and the like.

The above compounds may be used alone or in combination of two or more.

The above compound has an absorption maximum wavelength near 950 nm,
In addition, since there is almost no absorption in the visible region, the position of the photosensitive material can be easily detected in a recording apparatus for forming an image, and there is little coloring after processing.

Therefore, the compound in the present invention may be contained in any layer (for example, emulsion layer, intermediate layer, protective layer, back layer, etc.) in the light-sensitive material.

Even when the compound is contained in the emulsion layer, the compound of the present invention is oil-soluble, and is usually dispersed in an organic solvent and contained (by the so-called oil protection method) as described later. This is because there is no adverse effect such as fog.

When these dyes are used, they may be added to any of the layers constituting the silver halide photographic light-sensitive material of the present invention, for example, a silver halide emulsion layer or a silver halide such as a protective layer or an intermediate layer. It may be any layer such as a hydrophilic colloid layer adjacent to the emulsion layer or a packing layer and the protective layer.

It is more preferably a non-emulsion layer, and more preferably a layer farther from the light source than the emulsion layer.

The addition amount is not uniform depending on the kind of the dye and the emulsion conditions to be used, but is preferably 10 to 1000 mg / m ² , more preferably 30 to 600 mg / m ² per m ^{2 of} the light-sensitive material.

As a method of addition, in the case of a silver halide emulsion, a solution dissolved in water or a hydrophilic organic solvent (for example, methanol or ethanol) is preferably added after chemical ripening and before a coating step.

Hereinafter, specific examples of the infrared-absorbing dye represented by the general formula (I) and other infrared-absorbing dyes used in the present invention are shown, but the present invention is not limited thereto.

In the emulsion according to the present invention, various photographic additives can be used before and after physical ripening or chemical ripening. Known additives include, for example, Research Disclosure No. 17643 (December 1978) and No. 18716.
(November 1979).

The following table shows the types and locations of the compounds shown in these two research disclosures.

The photosensitive material according to the present invention is described in RD-17643, page 29, xx.
The development can be carried out by the usual method described on the left column on page 651 of RD-18716.

Examples of the support that can be used in the light-sensitive material according to the present invention include, for example, the aforementioned RD-17643, page 28 and RD-18716.
On page 647, left column. As a suitable support, a plastic film, paper, or the like may be used, and the surface of the support may be generally provided with an undercoat layer, corona discharge, ultraviolet irradiation, or the like in order to improve the adhesion of the coating layer. Then, the emulsion according to the present invention can be coated on one side or both sides of the support thus treated.

The present invention is applicable to all silver halide photographic materials, but is particularly suitable for high-sensitivity black-and-white photographic materials.

When the present invention is applied to medical X-ray radiography, for example, a fluorescent intensifying screen mainly containing a phosphor that generates near-ultraviolet light or visible light by exposure to penetrating radiation is used. It is desirable that this is brought into close contact with both surfaces of a light-sensitive material obtained by coating the emulsion of the present invention on both surfaces and then exposed.

The penetrating radiation referred to here is a high-energy electromagnetic wave and means X-rays and gamma rays.

The fluorescent intensifying screen refers to, for example, an intensifying screen mainly containing calcium tungstate as a fluorescent component or a fluorescent intensifying screen mainly containing a rare earth compound activated with terbium.

〔Example〕

 Next, the present invention will be described with reference to examples.

Example 1 (Preparation of seed crystal) The following solution was prepared.

Liquid A Water 23 Potassium bromide 4.1 g Gelatin 0.2 kg Liquid B Water 5.2 Potassium bromide 130 g Potassium iodide 3.6 g Gelatin 110 g 0.2 N sulfuric acid 77 cc Liquid C Water 6 Potassium bromide 1.90 kg Potassium iodide 54 g Gelatin 150 g Liquid D Water 5.4 Silver nitrate 190 g Solution E Water 6.4 Silver nitrate 2.82 kg Solution A was placed in a reaction vessel, kept at 60 ° C, and the other solutions were added at 59 ° C. At this time, solution B and solution D were added over 30 minutes by the control double jet method, and then solution C and solution E were added over 105 minutes by the control double jet method. Stirring was performed at 800 rpm. The flow rate is increased in proportion to the total surface area of the silver halide grains as the grains grow, and when the additive liquid flows in, no new growth nuclei are generated, and so-called Ostwald ripening is caused. The addition was at a non-spreading flow rate. During the addition of the silver ion solution and the halide ion solution, pAg was adjusted to 8.3 ± 0.05 using a potassium bromide solution, and the pH was adjusted to 2.0 using sulfuric acid.
Adjusted to ± 0.1. The resulting emulsion had a silver iodide content of 2 mol%, a grain size of 0.30 μm, σ / γ = 0.11, (111) planes of 5%, and the other (100) planes were slightly angled. It was a cubic monodisperse tetrahedral particle.

After the seed crystal has grown, the pH is adjusted to 6.00 ± using sodium carbonate solution.
After the temperature was adjusted to 0.3, the temperature was lowered to 40 ° C., a desalting treatment was carried out by a coagulation method using an aqueous solution of formalin naphthalene sulfonate and a magnesium sulfate solution, gelatin was further added, and pAg was 8.50 and pH was 5.85. Seed crystal emulsion (A)
16.9 kg was obtained. The resulting seed crystals were cooled and stored in a cool, dark place.

Next, particles were grown using the seed crystal (A) by the following method.

Preparation of Comparative Emulsion Em-1 First, the following solution was prepared. All amounts are given per mole of silver halide.

Solution J (reaction mother liquor) Gelatin 10 g Concentrated ammonia water 28 cc Glacial acetic acid 3 cc Finish to 600 cc water Solution K Potassium bromide 5 g Potassium iodide 3 g Gelatin 0.8 g Finish to 110 cc L solution L Potassium bromide 90 g Gelatin 2.0 g Finish to 240 cc water M liquid _{(0.75N) AgNO 3 9.9g NH 4} OH 7.0cc water 110cc finish N solution AgNO ₃ 130g NH ₄ OH finish 100cc water 240cc finish O solution of potassium bromide 94g water 165 cc P solution AgNO ₃ 9.9g NH ₄ OH 7.0 cc water Finished to 110 cc. The solution J was kept warm at 40 ° C. and stirred at 800 rpm with a stirrer.
The pH of Solution J was adjusted to 9.90 with acetic acid, and 62 g / AgX1 mol of seed crystal (A) was collected and dispersed and suspended therein. Thereafter, the solution P was added at a constant speed over 7 minutes to adjust the pAg to 7.3.
Further, solution K and solution M were simultaneously added over 20 minutes. The pAg at this time was constant at 7.30. (Step 1). Further, pH = 8.83, pA using potassium bromide solution and acetic acid for 10 minutes.
After adjusting to g = 9.0, solution N and solution L were added simultaneously over 30 minutes. At this time, the ratio of the inflow rate at the start of addition and the end of addition was 1:10, and the flow rate was increased with time. Also, the pH was reduced from 8.83 to 8.00 in proportion to the inflow. When the L solution and the N solution were added in only 2/3 of the total amount, the O solution was additionally injected and added at a constant speed over 8 minutes. At this time, the pAg increased from 9.0 to 11.0 (Step 2). Further, acetic acid was added to adjust the pH to 8.0. Next, an excessive salt was removed from the suspension by a desalting method as described below to obtain an emulsion. While maintaining the suspension at 40 ° C., a formalin condensate of sodium naphthalenesulfonate (5 g / AgX1m
ol) and MgSO ₄ (8 g / AgX1 mol) were added, stirred for 5 minutes and allowed to stand. Next, the supernatant was discharged to a liquid volume of 200 cc per 1 mol of AgX. Thereafter, pure water (1.81 / AgX1 mol) at 40 ° C. was added and stirred for 5 minutes. Next, MgSO ₄ (20 g / AgX1 mol) was added, the mixture was stirred and allowed to stand as described above, and the supernatant was removed to desalinate.
Next, gelatin was added to disperse the AgX coagulate again, and the mixture was stirred and stirred at 55 ° C. for 20 minutes to obtain Comparative Emulsion Em-1.

Adjustment of Em-2 When Step 1 of Em-1 was completed, the following compounds were added to Table-1.
(Em-2) was obtained in the same manner as in Em-1 except that the amount shown in (1) was added.

These emulsions were all monodisperse grains having an average grain size of 0.06 μm and a silver iodide content of about 2 mol%.

Next, the obtained particles were subjected to chemical sensitization. That is, ammonium thiocyanate, chloroauric acid and hypo were added, and gold-
Sulfur sensitization was performed.

Thereafter, 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene was added, followed by KI and a spectral sensitizing dye A,
(B) 300 mg.5 mg / 1 mol of AgX1 mol was added to each, and spectral sensitization was performed.

Spectral sensitizing dye Next, a coating solution for the emulsion layer containing the obtained emulsion and a coating solution for the protective layer are simultaneously coated on both sides of the undercoated polyester film support in the order of the emulsion layer and the protective layer from the support side in the order of two layers. After drying, a silver halide photographic film was prepared.

The following additives were added to the emulsion layer per 1 mol of AgX.

The following compounds were added to the protective layer per 1 g of gelatin.

Further, as shown in Table 1, an infrared absorbing dye was added to the emulsion layer or the protective layer.

As the undercoat liquid, glycidyl methacrylate 50 wt%,
Methyl methacrylate 10wt%, butyl methacrylate 40
The concentration of a copolymer consisting of three types of monomers of wt% is
The copolymer was diluted to 10% by weight and a copolymer aqueous dispersion was used.

Table 1 shows the samples thus obtained. The gelatin amount of the unexposed film of this sample was 3.10 g / m ² per one side.

[Sensitometry] Using standard light B described in "New Edition, Illumination Data Book" as a light source, the film was exposed to both sides of a film with an exposure time of 0.1 second and 3.2 cms with a non-filter so as to have the same light amount. The samples were treated with an XD-SR developer for 45 seconds using an SRX-501 automatic developing machine (manufactured by Konica Corporation) to determine the sensitivity of each sample. The sensitivity was obtained by calculating the reciprocal of the amount of light required for increasing the blackening density by 1.0, and expressing the relative sensitivity with the sensitivity of Sample 1 in Table 1 being 100.

In addition, as a storage test, the obtained samples were left in a constant temperature room at 23 ° C. for 3 days, those left in a constant temperature room at 50 ° C. for 3 days, and untreated fresh samples. These samples were subjected to XD-SR using an SRX-51 automatic machine (manufactured by Konica Corporation).
Processing was performed for 45 seconds with a developer, and fog of each sample was measured.

 Table 1 also shows these results.

As shown in Table 1, the sample subjected to the reduction treatment has high sensitivity but shows an increase in fog in the storage test.

It can be seen that the sample of the present invention has high sensitivity and an increase in fog is suppressed even in the storage stability test.

Example 2 A sample obtained in the same manner as in Example 1 was subjected to SRX.
An increase in fog when a film was placed on the sensor and irradiated with infrared rays for 10 minutes was measured with an infrared sensor for film detection provided at the film entrance of a -501 automatic developing machine (manufactured by Konica Corporation).

 Table 2 shows these results.

As shown in Table 2, the fog of the sample subjected to the reduction treatment is increased by the irradiation of the infrared sensor.

It can be seen that the sample of the present invention does not increase fog due to infrared rays even in the sample subjected to the reduction treatment.

〔The invention's effect〕

According to the present invention, a silver halide photographic light-sensitive material having high sensitivity and high density without fogging caused by an infrared sensor of an automatic processor is obtained.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) G03C 1/035 G03C 1/83 G03C 1/00

Claims (1)

(57) [Claims] At least one surface of a support is provided with at least one emulsion layer containing photosensitive silver halide grains which have been grown by enclosing a shell layer subjected to a reduction treatment and then chemically sensitized. A silver halide photographic light-sensitive material comprising an infrared absorbing dye in at least one of the constituent layers.