JPH11143013A - Production of silver halide photographic material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a silver halide photographic material containing an aryl compd. used for preventing the occurrence of spot defects due to metallic impurities formed in the preparation of a substrate. SOLUTION: When a silver halide emulsion is prepd., chemically or optically sensitized and applied to a substrate to produce a silver halide photographic material, an aryl compd. having at least two hydroxyl groups and at least one substituent represented by sulfonic acid, hydroxyl, carboxyl or hydroxymethyl is added to the silver halide emulsion by <0.03 mol per mol silver before the application.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a silver halide photographic material. In particular, the present invention relates to the use of aryl derivatives in a method for preparing a silver halide emulsion to prevent the formation of spot defects due to metallic impurities.

[0002]

BACKGROUND OF THE INVENTION Silver halide emulsions are usually prepared by precipitating silver halide (silver bromide, silver iodide, silver chloride, or mixtures thereof) in the presence of a hydrophilic colloid (usually gelatin). Prepared. Thereafter, the silver halide emulsion is subjected to a sensitization step to enhance its photosensitivity. There are mainly two sensitization methods, spectral sensitization and chemical sensitization. Spectral sensitization involves the addition of a spectral sensitizing dye that can be absorbed on the surface of the silver halide grains to make the emulsion sensitive to the imaging radiation or the radiation emitted by the phosphor (typically visible or infrared). I do. Chemical sensitization involves the addition of various chemicals to achieve defined sensitivity and contrast values. Conventional methods for chemically sensitizing silver halide photographic emulsions include sulfur sensitization, noble metal sensitization, and reduction sensitization. Combinations of the above sensitization methods, such as sulfur-noble metal sensitization, reduction-noble metal sensitization, and the like, are well known to those skilled in the art.

A specific method for enhancing chemical sensitization is as follows:
It is disclosed in numerous patent publications and patent applications and publications. For example, Research Disclosure , 1
See September 994, 36544, Chapter IV, pages 510-511, for a wide range of illustrations of each of the above methods.

After the sensitization step, the silver halide emulsion is coated on a support together with a coating aid. An extensive description of useful coating aids can be found, for example, in Research
Disclosure , September 1996, No. 38597,
"Photographic Silver Halide Emulsions, Preparations, Addenda, Systems and Processing (Photographic Silver Halide E
mulsions, Preparations, Addenda, Systems and Proce
ssing) "in Section IX.

In preparing silver halide elements, care must be taken that said elements are free of metal impurities. However, metal impurities may be generated as metal particles from an apparatus or the like during the manufacturing, for example. Further, metal impurities can be generated in any step from preparation of the support to final coating. Although different metals such as copper or nickel may be present in the final material, the main metallic impurity is iron particulates. The presence of iron ions, such as iron (III), can suppress the sensitivity of the silver halide and produce a low density halo that appears as white spots on the developed film. The presence of metal ions microparticles or iron ions such as iron (II)
May emit one or two electrons. that is,
Produces a sensitized halo that appears as black spots on the developed film. White or black spots are the opposite, simply meaning that the spots appear whiter or blacker than the clean, clean, surrounding area of the developed film. White and / or black spots in the developed image degrade image quality and render it unusable in many photographic films, especially X-ray applications that interfere with medical diagnostics. One solution used in the art to control or eliminate the above deficiencies is to add sequestering or chelating agents. The chemical generally forms a strong complex with the metal, so that the metal can be removed from the photosensitive element, thereby preventing speckle formation.

[0006] Several different types of complexing agents have been described in the prior art as follows. U.S. Patent 3,344
No. 3,951 discloses the use of phosphate esters in photographic elements to prevent defect formation caused by metal particles. U.S. Pat.No. 4,340,665 discloses a method for preventing the formation of defects caused by iron impurities in a photographic element.
The use of phosphate and amine complexing agents is disclosed. U.S. Pat. No. 3,925,086 discloses the use of azotriazole and azotetrazole as defect inhibitors in photographic silver halide or in a developing bath.
U.S. Pat. No. 3,330,312 discloses the use of sulfosalicylic acid in photographic elements to reduce speckle formation from metal particles. EP 733,940 discloses that
To reduce spot formation from pseudo metal particle impurities,
The use of both phosphate and sulfosalicylic acid in photographic elements is disclosed. German Patent 1,350,303 discloses the use of thienyl or furyl compounds to reduce the likelihood of spot formation due to metal or metal oxide impurities. German Patent 1,350,302 discloses the use of aldoxime compounds to reduce the likelihood of spot formation due to metal or metal oxide impurities. U.S. Pat. No. 4,340,665 discloses the use of phosphate and hydroxyethylenediamine triacetate in a silver halide photographic element to reduce metal grain impurities.

[0007] Although the above method substantially reduces speckles, a decrease in sensitivity characteristics is usually observed. Therefore, there is a demand for materials to reduce spot defects due to metallic impurities without deteriorating sensitivity characteristics. Although hydroxy-substituted aryl compounds induce silver halide emulsions, the function of the materials in the emulsion is relevant for various purposes, regardless of metal impurities.

US Pat. No. 5,028,520 discloses the use of potassium hydroquinonesulfonate on tabular silver halide emulsions in an amount of 0.03 to 0.5 mole per mole of silver to reduce surface gloss. It has been disclosed. It is also disclosed that no effect is obtained when the compound is used in an amount of less than 0.03 mol per mol of silver.
JP-A-54-40729, JP-A-56-1936 and JP-A-62-21
No. 143 discloses the use of polyhydroxybenzene on a cubic silver halide emulsion to reduce pressure sensitive properties in graphic arts films. European Patent No. 452772, No. 476521, No. 482599 and No. 488029 have functional groups that reduce the pressure-sensitive properties of the final film by increasing the absorption of silver halide grains. The use of polyhydroxybenzene derivatives having the same is disclosed. European Patent No. 339870
The publication discloses a silver halide photographic emulsion having a sensitizing amount of a polyalkylene glycol compound and a haze reducing amount of an arylhydroxy compound in reactive association with each other.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a silver halide emulsion which can prevent formation of spot defects due to metallic impurities.

[0010]

The present invention comprises: (a) a step of preparing a silver halide emulsion; (b) a step of chemically or optically sensitizing the silver halide emulsion;
(c) an aryl compound having at least two hydroxyl groups and at least one other substituent represented by a sulfonic acid group, a hydroxyl group, a carboxyl group or a hydroxymethyl group, in an amount of less than 0.03 mol per mol of silver; There is provided a method for producing a silver halide photographic material, comprising a step of adding to a silver emulsion and a step of (d) applying the silver halide emulsion to a support. The addition of the aryl compound reduces or eliminates spot defects due to metallic impurities in a silver halide photographic emulsion containing silver halide tabular grains.

The aryl compound is represented by the following formula.

Embedded image (Wherein, R _{1 to} R ₄ are each selected from the group consisting of a hydrogen atom, a sulfonic acid group, a hydroxyl group, a carboxyl group, and a hydroxymethyl group, but at least one of R _{1 to} R ₄ is not a hydrogen atom .)

In another embodiment of the present invention, a silver halide photographic material comprises a support coated with at least one silver halide emulsion layer, said silver halide emulsion layer comprising at least two silver halide emulsion layers. An aryl compound having a hydroxyl group and at least one other substituent represented by a sulfonic acid group, a hydroxyl group, a carboxyl group or a hydroxymethyl group is contained in an amount of less than 0.03 mol per mol of silver.

[0013]

DETAILED DESCRIPTION OF THE INVENTION The method of preparing a silver halide photographic element typically includes the following steps: (a) an emulsion preparation step, (b) a chemical and optical sensitization step, and (c) a specific step. Adding the aryl compound to the silver halide emulsion; and (d) applying the silver halide emulsion.

Step (a): Preparation of silver halide emulsion
The silver halide emulsion preparing step (a) generally comprises (i) a nucleation step in which silver halide grain species are formed,
(ii) one or more growth steps in which the grain species achieves final dimensions;
And (iii) a washing step to remove any soluble salts from the final emulsion. Further, between the nucleation step (i) and the growth step (ii) and / or the growth step (ii) and the washing step
An aging step may be performed during (iii).

The silver halide emulsion can be prepared by a single jet method, a double jet method or a combination thereof, and can be ripened by, for example, an ammonia method, a neutralization method or an acidic method. Parameters that can be adjusted to control particle growth include pH, pAg,
Temperatures, reaction vessel shapes and dimensions, and reaction methods (eg, accelerated or constant flow precipitation, intermittent precipitation, ultrafiltration during precipitation, backmixing, and combinations thereof). A silver halide solvent (e.g., ammonia, thioether, thiourea, etc.) optionally has a grain size,
It may be used to control grain structure, grain size distribution and grain growth rate. The following references provide a useful overview: Trivelli and Smith, The Photo
Graphic Journal , Volume LXXIX, May 1939
March, pages 330-338; TH James, The Theory
Of the Photographic Process , 4th Edition, Chapter 3; by P. Glafkides, Hemy & Physique For
Doo chromatography click, Paul Montel (1967 years); GF D
Photographic Emulsion Chemis by uffin
Tree , The Focal Press (1966); VL Zelik
Man, Making and Coating Photog
Rafic Emulsions , The Focal Press (19
1966); U.S. Patent No. 2,222,264; 2,592,250
No. 3,650,757; No. 3,917,485;
No. 3,790,387; No. 3,716,276; and No. 3,979,213; and Research Disclosure
Catcher over, September 1994, No. 36544, "Photographic Silver halide emulsion's, preparation's, addenda, Systems and Processing".

In the preparation of the silver halide emulsion, a commonly used halogen composition of silver halide grains can be used. Commonly used silver halides include silver chloride, silver bromide, silver iodide, silver iodochloride, silver iodobromide, silver iodobromochloride and the like. Among them, silver bromide and silver iodobromide are preferred halogens containing a silver iodide bromide composition containing 0 to 10 mol%, preferably 0.2 to 5 mol%, particularly 0.5 to 1.5 mol% of silver iodide. It is a silver halide composition. The halogen composition of the individual grains may be homogeneous or heterogeneous.

Gelatin is preferred as the binder for the silver halide emulsion, but dextran,
Other hydrophilic substances such as cellulose derivatives (eg, hydroxyethylcellulose, carboxymethylcellulose), collagen derivatives, colloidal albumin or casein, polysaccharides, synthetic hydrophilic polymers (eg, polyvinylpyrrolidone, polyacrylamide, polyvinyl alcohol, polyvinyl pyrazole) and the like. Sexual colloids can be used alone or in combination. Highly deionized gelatin,
Gelatin derivatives such as acetylated gelatin and phthalated gelatin can also be used. Hydrophilic colloids, synthetic polymer binders, acrylamide and methacrylamide polymers, alkyl and sulfoalkyl acrylate and methacrylate polymers, polyvinyl alcohol and its derivatives, polyvinyl lactam,
It is also well known to use in combination with peptizers such as polyamide, polyamine, polyvinyl acetate and the like.

The grains of the silver halide emulsion are as follows:
It may be coarse or fine, and the grain size distribution of the silver halide emulsion may be narrow or wide. Silver halide grains include regular grains having a regular crystal structure such as cubic, octahedral and tetradecahedral or spherical or irregular crystal structures, regular grains having crystal defects such as twin planes, and the like. It may be tabular regular particles or a combination thereof. Further, the grain structure of the silver halide may be uniform from the inside to the outside, or may be a multilayer structure. In a simple embodiment, the particles may include a core and a shell, wherein the core and the shell have different halide compositions, and / or
Alternatively, another modification such as addition of a doping agent may be performed. In addition to having a core and shell having separate compositions, the silver halide grains may include other morphologies therebetween. The silver halide may be of a type capable of forming a latent image mainly on its surface or of a type capable of forming a latent image inside its grains.

Preferably, the tabular silver halide emulsion has an aspect ratio of at least 2: 1, especially 2: 1.
~ 20: 1, more preferably from 2: 1 to 14: 1, most preferably from 2: 1 to 8: 1. In the present invention, the aspect ratio refers to an average diameter / thickness ratio of silver halide grains. The average diameter of the tabular silver halide grains is about
0.3 to about 5 μm, preferably about 0.5 to about 3 μm, especially about
It ranges from 0.8 to about 1.5 μm. The thickness of the tabular silver halide grains is less than 0.4 μm, preferably less than 0.3 μm, especially
It is in the range of 0.1 to 0.3 μm. The projected area of the tabular silver halide grains accounts for at least 50%, at least 80%, especially at least 90%, of the projected area of all silver halide grains of the emulsion.

The dimensions and characteristics of the tabular silver halide grains described above can be easily confirmed by procedures well known to those skilled in the art. Here, the "diameter" of the tabular silver halide grains is defined as the diameter of a circle having an area equal to the projected area of the grains. The "thickness" of tabular silver halide grains
Refers to the distance between two substantially parallel major planes that make up the particle. According to the measurement of the diameter and thickness of each particle, the ratio of diameter / thickness of each particle can be calculated, and the diameter / diameter of all tabular particles /
The average diameter / thickness ratio is obtained by averaging the thickness ratios. By this definition, the average diameter / thickness ratio is the average of the individual tabular grain diameter / thickness ratios. In fact, a simpler method is to measure the ratio of the average diameter to the average thickness of the tabular grains and calculate the average diameter / thickness ratio as the ratio of the two averages. Whatever method is used, there is no significant difference in the average diameter / thickness ratio obtained.

Silver halide emulsions containing tabular silver halide can be prepared by various methods well known to those skilled in the preparation of photographic materials.

The preparation of silver halide emulsions containing tabular silver halide grains is described, for example, in the following documents: de Cugnac and Chateau, "Evolution of the Morphology of".・ Silver Bromide Crystals Dualing Physical Reopening ” Science and Industry
Leeds Photographics, Vol. 33, No. 2 (1
962), pp. 121-125; by Gutoff, "Nucreation and Grouse-Rates Dualing."
The Precipitation of Silver Halide
Photographic emulsions ", Photograph
Quick Science and Engineering , No. 1
Volume 4, Issue 4 (1970), pp. 248-257; Berry
"Effects of Evolution on the Growth of Silver Bromide Microcrystals," Vol. 5, No. 6 (1961), 332-3
Page 36: Research Disclosure , September 1994, No. 36544, "Photographic Silver.
Halide Emulsions, Preparations, Addenda, Systems and Processing "; U.S. Pat. Nos. 4,063,951; 4,067,739; 4,18.
No. 4,878; No. 4,434,226; No. 4,414,310; No. 4,386,156; and No. 4,414,306; and European Patent Application No. 263,508.

At the end of silver halide grain formation, the water-soluble salt is removed from the emulsion by procedures known in the art. Suitable washing methods include the combination of ripening media and soluble salts dissolved therein, for example, dialysis or electrodialysis to remove soluble salts from silver halide emulsions,
Alternatively, it can be removed by conventional methods, such as a combination of osmosis or reverse osmosis to remove the ripening medium.

Among the known methods for removing ripening media and soluble salts while keeping the silver halide grains in the remaining dispersion, ultrafiltration is a particularly advantageous washing method in the practice of this invention. is there. Usually, an ultrafiltration device containing an inert, non-ionic polymer membrane is used as the washing device. Because the silver halide grains are large in the combination of the ripening medium and the soluble salts or ions, the silver halide grains are removed by the membrane during removal of the ripening medium and the soluble salts dissolved therein. Will be retained.

Step (b): Chemically and optically sensitized silver halide grain emulsions are usually completely dispersed before use and mixed with gelatin or other peptizer dispersants to achieve optimal sensitivity. To a known method. For an extensive description of methods and compounds useful for chemical and optical sensitization, see Research Disclosure.
Jar , September 1996, Issue 38597, "Photographic Silver Halide Emulsions, Preparations, Addenda, Systems and Processing", Sections IV and V.

Chemical sensitization is achieved by adding a chemical sensitizer and another compound to the silver halide emulsion, followed by so-called chemical ripening at an elevated temperature for a predetermined time. It can be chemically sensitized by various chemical sensitizers such as gold, sulfur, a reducing agent, platinum, selenium, and sulfur + gold. Tabular silver halide grains are preferably chemically sensitized with at least one gold sensitizer and at least one sulfur sensitizer after grain formation and desalting. During chemical sensitization,
The photographic performance of the resulting silver halide emulsion can be improved by adding other compounds such as anti-fogging agents, stabilizers, optical stabilizers, supersensitizers and the like.

The gold sensitization is carried out by adding a gold sensitizer to the emulsion and stirring the emulsion at a high temperature, preferably at least 40 ° C., for a predetermined time. As the gold sensitizer, a gold compound having an oxidation number of +1 or +3 can be usually used. Preferred examples of gold sensitizers are chloroauric acid and salts of chloroauric acid and gold complexes as described in US Pat. No. 2,399,083. Specific examples of the gold sensitizer include chloroauric acid, potassium chloroaurate, gold trichloride, sodium gold thiosulfate, potassium gold thiocyanate, potassium iodoauric acid, tetracyanoauric acid, and 2-gold sulfobenzothiazole methchloride. And ammonium gold thiocyanate.

In the sulfur sensitization, a sulfur sensitizer is added to a silver halide emulsion, and the emulsion is preferably added to a silver halide emulsion.
This is performed by stirring at a high temperature of not less than ° C. for a predetermined time. Useful examples of sulfur sensitizers include thiosulfonates, thiocyanates, sulfinates, thioethers and sulfur atoms.

The amounts of gold sensitizer and sulfur sensitizer may vary depending on the activity of the gold sensitizer and sulfur sensitizer, the type and size of silver halide grains, the temperature, pH and time of chemical ripening. Varies depending on conditions. In the present invention, the amount of the gold sensitizer is preferably 1 to 20 mg per mol of silver, and the amount of the sulfur sensitizer is 1 to 100 mg per mol of silver. Further, the temperature of the chemical ripening is preferably 45 ° C or more,
Especially 50-80 ° C. pAg and pH can take any values.

During the chemical sensitization, the temperature and the order of adding the gold sensitizer and the sulfur sensitizer are not particularly limited. For example, the gold sensitizer and the sulfur sensitizer can be added simultaneously or separately at an early stage of chemical sensitization or at a later stage. Usually, the gold sensitizer and the sulfur sensitizer are added to the silver halide emulsion in the form of an aqueous solution, a solution of a water-miscible organic solvent such as methanol, ethanol and acetone, or a mixture thereof.

The stabilizer is preferably added any time before the addition of the sulfur sensitizer. Stabilizers are believed to act as digestion stabilizers and location indicators for sulfur sensitizers, although their action is not yet fully understood. Preferably, the stabilizer is added before the addition of the sulfur chemical sensitizer in an amount of 1 to 500 mg, especially 10 to 300 mg per mole of silver. Specific examples of useful stabilizers include thiazole derivatives; benzothiazole derivatives; mercapto-substituted heterocyclic compounds (eg, mercaptotetrazole, mercaptotriazole, mercaptodiazole, mercaptopyrimidine, mercaptoazole, etc.); Triazole; tetrazole; and sulfonic acid derivatives and benzenesulfonic acid derivatives.
Azaindene, especially tetraazaindene, is preferably used.

Further, the silver halide grain emulsion may be optically sensitized to a desired visible region. The method of spectral sensitization is not particularly limited, for example, cyanine dye, merocyanine dye, complex cyanine and merocyanine dye, oxonol dye, hemioxonol dye,
Optical sensitization may be performed by using an optical sensitizer containing a styryl dye and a streptocyanine dye alone or in combination. Useful optical sensitizers include cyanines derived from quinoline, pyridine, isoquinoline, benzindole, oxazole, thiazole, selenazole, imidazole. Particularly useful optical sensitizers are benzoxazole-, benzimidazole- and benzothiazole-carbocyanine dyes. The addition of the spectral sensitizer is usually performed after the completion of the chemical sensitization. Alternatively, the spectral sensitization can be performed at the same time as or before the chemical sensitization, or can be started before the completion of silver halide precipitation. When spectral sensitization is performed before chemical sensitization, preferential absorption of the spectral sensitizing dye on the crystal planes of the tabular grains causes selective chemical sensitization on different crystal planes of the tabular grains. Conceivable. Preferably, the spectral sensitizer, when absorbed on the surface of the silver halide grains, has a J-aggregate and a sharp absorption band (J-band) due to a deep color effect based on the maximum absorption of the free dye in aqueous solution. Generate

The intensity of the sharp absorption band (J-band) based on the spectral sensitizing dye absorbed on the surface of the photosensitive silver halide grain depends on the amount of the specific dye selected and the size and chemical composition of the grain. Things that change
It is known in the field of radiographic materials. J-band spectrum at a concentration of 25-100% or more of the monolayer coating weight of the total surface area of the silver halide grains. J-band intensity of silver halide grains of the above dimensions and chemical composition absorbed by sensitizing dye. Is the largest. The optimal dye concentration standard is
It is selected in the range of 0.5 to 20 mmol, preferably 2 to 10 mmol, per 1 mol of silver halide. Spectral sensitizing dyes that produce J-aggregates are well known to those of skill in the art and are described, for example, by FM Hamer, Cyanine Soy and Related Compounds, published by John Wiley and Sons,
1964, Chapter XVII, and TH James al., The Se
Olly of the Photographic Process , 4th Edition, MacMillan Publishing, 1977, Chapter 8.

In a preferred embodiment, the J-band excitable dye is a cyanine dye having two basic heterocyclic nuclei linked by a methine group bond. The heterocyclic nucleus is
Preferably, it includes a benzene ring fused to enhance J aggregation. The heterocyclic nucleus is preferably quinolinium, benzoxazolium, benzothiazolium, benzoselenazolium, benzimidazolium, naphthoxazolium, naphthothiazolium and quaternary salt of naphthoselenazolium.

As the cyanine dye linked by a methine bond, pyrrolidone, oxazoline, thiazoline, pyrrole, oxazole, thiazole, selenazole, tetrazole and pyridine, and an alicyclic hydrocarbon or an aromatic hydrocarbon may have the above-mentioned nucleus (for example, Two basic heterocyclic nuclei, such as nuclei obtained by fusion with indolenine, benzindolenin, indole, benzoxazole, naphthoxazole, benzothiazole, naphthothiazole, benzoselenazole, benzimidazole and quinoline) Is mentioned. These nuclei can have substituents.

Merocyanine dyes linked by methine linkages include basic heterocyclic and acidic nuclei of the type described above (eg, barbituric acid, 2-thiobarbituric acid, rhodanine, hydantoin, 2-thiohydantoin, 4 -Thiohydantoin, 2-pyrazolin-5-one, 2-isoxazoline-5-
5- or 6 formed from on, indan-1,3-dione, cyclohexane-1,3-dione and isoquinolin-4-one
-Membered heterocyclic nucleus).

Preferred dyes are cyanine dyes of the type represented by the following formula:

Embedded image

In the above formula, n, m and d each independently represent 0 or 1; L represents a methine bond (for example, = CH-, ≡C (C ₂ H ₅ ), etc.); R ₁ and R ₂ are each a substituted or unsubstituted alkyl group, preferably a lower alkyl group having 1 to 4 carbon atoms (eg, methyl, ethyl,
Propyl, butyl, cyclohexyl and dodecyl),
Hydroxyalkyl groups (eg, β-hydroxyethyl and Ω-hydroxybutyl), alkoxyalkyl groups (eg, β-methoxyethyl and Ω-butoxyethyl), carboxyalkyl groups (eg, β-carboxyethyl and Ω-carboxybutyl) , A sulfoalkyl group (for example, β-sulfoethyl and Ω-sulfobutyl), a sulfate alkyl group (for example, β-sulfateethyl and Ω-sulfatebutyl), an acyloxyalkyl group (for example, β-acetoxyethyl, γ- Acetoxypropyl and Ω-butylyloxybutyl), alkoxycarbonylalkyl groups (eg, β-methoxycarbonylethyl and Ω-ethoxycarbonylbutyl), benzyl, phenethyl or aryl groups of up to 30 carbon atoms (eg, phenyl, tolyl, xylyl, Chloro X represents an acid anion (eg, chloride, bromide, iodide, thiocyanate, sulfate, perchlorate, p-toluenesulfonate and methylsulfate); when p is 0, methine linkage Forms an inner salt; Z ₁ and Z ₂ are
Non-metallic atoms required to form the same or different, identical one or fused 5- or 6-membered heterocyclic nucleus (benzothiazole, 3-, 5-, 6- or 7-
Chlorobenzothiazole, 4-, 5- or 6-methylbenzothiazole, 5- or 6-bromobenzothiazole, 4- or 5-phenylbenzothiazole, 4-, 5- or 6-methoxybenzothiazole, 5,6- Benzothiazole nucleus such as dimethylbenzothiazole and 5- or 6-hydroxybenzothiazole; α-naphthothiazole, β-naphthothiazole, 5-methoxy-β-naphthothiazole, 5-ethoxy
naphthothiazole nuclei such as -α-naphthothiazole and 8-methoxy-α-naphthothiazole; benzoselenazole,
Benzoselenazole nucleus such as 5-chloro-benzoselenazole and tetrahydrobenzoselenazole; naphthoselenazole nucleus such as α-naphthoselenazole and β-naphthoselenazole; benzoxazole, 5- or 6-hydroxybenzoxazole, 5 Benzoxazole nuclei such as -chloro-benzoxazole, 5- or 6-methoxybenzoxazole, 5-phenylbenzoxazole and 5,6-dimethylbenzoxazole; naphthoxazole nuclei such as α-naphthoxazole and β-naphthoxazole; 2 -Quinoline, 6-, 7- or 8-methyl-2-quinoline, 4-, 6- or 8-chloro-2-quinoline, 5-, 6- or 7-ethoxy-2-quinoline and 6- or 7- Hydroxy-
2-quinoline nucleus such as 2-quinoline; 4-quinoline, 7- or 8-
4- such as methyl-4-quinoline and 6-methoxy-4-quinoline
Quinoline nucleus; benzimidazole nucleus such as benzimidazole, 5-chloro-benzimidazole and 5,6-dichloro-benzimidazole; thiazole nucleus such as 4- or 5-methylthiazole, 5-phenylthiazole and 4,5-dimethylthiazole 4- or 5-methyloxazole;
4-phenyloxazole, 4-ethyloxazole and
An oxazole nucleus such as 4,5-dimethyloxazole; and
Represents a selenazole nucleus such as 4-methyl selenazole and 4-phenyl selenazole. Particularly preferred dyes within the above-mentioned class are those having an internal base and / or
Alternatively, it is derived from the above-mentioned benzoxazole nucleus and benzimidazole nucleus. Common methine-based spectral sensitizing dyes include those listed below.

[0039]

Embedded image

Embedded image

Methine-based spectral sensitizing dyes are generally known in the art. Specifically, U.S. Pat.
No. 503,776; No. 2,912,329; No. 3,148,187
No. 3,397,060; 3,573,916; and 3,822,136, and French Patent No. 1,118,778. Its use in photographic emulsions is well known and is used at an optimum concentration corresponding to the desired value of the speed / haze ratio. Optimal or near-optimal concentrations of the spectral sensitizing dye are usually from 10 to 500 mg, preferably from 50 to 200 mg, especially from 50 to 10 mg / mol of silver.
0 mg.

Spectral sensitizing dyes, when used in combination, result in supersensitization (ie, spectral sensitization wider than the spectral range obtained from the concentration of the dye alone, or spectral sensitization resulting from another effect of the dye). Sometimes. Hypersensitization is based on spectral sensitizing dyes and Gilman
Author, Photographic Science and Engineering
Nearing , 18, 418-480, 1974 and U.S. Pat. Nos. 2,933,390; 3,635,721; 3,743,510; 3,615,613;
No. 3,615,641; US Pat. No. 3,617,295; and US Pat.
No. 635,721, which is obtained by a selected combination with other additives such as stabilizers and anti-fogging agents, development accelerators and inhibitors, fluorescent bleaching agents, surfactants and antistatic agents.

Step (c): Addition of Specific Aryl Compound After that, the obtained silver halide emulsion is coated on a suitable support to prepare a silver halide photographic material. According to the method of the present invention, before the silver halide emulsion is coated on the support, at least two different groups represented by at least two hydroxyl groups and sulfonic acid groups, hydroxyl groups, carboxyl groups or hydroxymethyl groups are used. Of the aryl compound having a substituent of 0.03 per mole of silver.
It is added to the silver halide emulsion in less than a molar amount.
The following are preferred as the aryl compound.

Embedded image (Wherein, R _{1 to} R ₄ are each selected from the group consisting of a hydrogen atom, a sulfonic acid group, a hydroxyl group, a carboxyl group, and a hydroxymethyl group, but at least one of R _{1 to} R ₄ is not a hydrogen atom .)

Preferred aryl compounds represented by the above formula are listed below.

Embedded image

The amount of the aryl compound is preferably in the range of 0.0001 to 0.03 mol per mol of silver, particularly preferably 0.1 to 0.03 mol per mol of silver.
001 to 0.03 mole, most preferably 0.005 to 0.05 mole per silver mole
0.03 mol.

The use of the above aryl compound can reduce spot defects due to metallic impurities in the silver halide photographic emulsion. Metallic impurities include metals, especially heavy metals (eg, iron, copper, chromium, tin, nickel, etc.) and aluminum. The metal contaminates the emulsion during various steps such as preparation, coating and / or storage, causing sensitization or desensitization of the silver halide grains, resulting in black or white in the developed photographic material. Spots appear. The aryl compound used in the present invention can chelate metal ions, so that the concentration of released metal ions can be reduced to a harmless level.
As a result, free silver halide emulsions containing metal impurities contain less than 1 μmol of free metal per gram of emulsion.

For example, stabilizers or antifogging agents such as assignmentden, triazole, tetrazole, imidazolium salts and polyhydroxy compounds; development accelerators such as benzyl alcohol and polyoxyethylene compounds; chroman, coumaran and bisphenol compounds And other additives such as lubricants such as waxes, higher fatty acid glycerides, higher alcohol esters of higher fatty acids, etc. to the silver halide emulsion before or during coating. it can. Coating aids, permeability modifiers in developing solutions, foam inhibitors, antistatic agents and matting agents may be used. Research for other useful additives
・ Disclosure , No. 17643, January 1978
February; Research Disclosure , No. 18431, 1
August 997; Research Disclosure , 3081
Issue 19, Chapter IV, December 1989; and Research De
Disclosure , No. 36544, September 1994.

Step (d): Coating of silver halide emulsion
Suitable support materials for the fabric include glass, paper, polyethylene-coated paper, metal, and polymer films (eg, cellulose nitrate, cellulose acetate, polystyrene, polyethylene terephthalate, polyethylene, polypropylene, etc.).

Preferred photosensitive silver halide photographic materials are
A radiation-sensitive element used for X-ray imaging comprising a silver halide emulsion layer coated on both sides of a support, preferably a polyethylene terephthalate support. Preferably, the silver halide emulsions are coated on the support per surface at silver coverage in the range of 1.5~3g / m ^2. The radiation-sensitive element is typically associated with an intensifying screen so that it is exposed to radiation emitted from the intensifying screen. Intensifying screens consist of a relatively thin phosphor layer that converts x-rays into radiation such as light useful for imaging (eg, visible light). The intensifying screen provides a wider X than the area absorbed by the photosensitive element.
X required to obtain a useful image from absorbing lines
Used to reduce radiation dose. Of total X-ray dose
Intensifying screens that absorb more than 25% are preferably used. Phosphors can emit in the blue, green or red region of the ultraviolet, visible spectrum, depending on their chemical composition, and silver halide emulsions are sensitized in the wavelength region of radiation emitted by the screen. You. Sensitization is performed using a spectral sensitizing dye absorbed on the surface of the silver halide grains, as described above.

X-ray photographic materials include, for example, undercoat layers, surfactants, filter dyes, intermediate layers, protective layers, antihalation layers, barrier layers, dye underlayers, development inhibiting compounds, photosensitizers, Agent, plasticizer, chemical sensitizer, U
Other layers and additives such as V absorbers and the like may also be included. Dye underlayers are particularly useful in keeping the double coated silver halide radiographic material from intermingling. Known dye underlayers are disclosed in U.S. Pat. No. 4,900,652;
Nos. 55,221; 4,857,446; and 4,80.
3,150. Preferably, a dye underlayer is applied on at least one side of the support, especially on both sides of the support, before applying the at least two silver halide emulsions.

Preferably, the silver halide radiographic material is cured beforehand. Examples of organic or inorganic curing agents include chromium salts (eg, chromium alum, chromium acetate), aldehydes (eg, formaldehyde and glutaraldehyde), isocyanate compounds (hexamethylene diisocyanate), active halogen compounds (eg, 2,
4-dichloro-6-hydroxy-s-triazine), epoxy compound (eg, tetramethylene glycol diglycidyl ether), N-methylol derivative (eg, dimethylol urea, methylol dimethylhydantoin), aziridine, mucohalogenoic acid (eg, muco Chloric acid), active vinyl derivatives (eg, vinylsulfonyl derivatives and hydroxy-substituted vinylsulfonyl derivatives), and the like. Other literature on well-known curing agents can be found in Research
・ Disclosure , December 1989, Vol. 308, No. 30811
Issue 9, Chapter X; and Research Disclosure , 1
It can be found in September 994, Vol. 365, No. 36544, Chapter II (b). A detailed description of photographic materials and various layers and additives can be found in Research Disclosure , No. 17643, 19
December '78; Research Disclosure , No. 1843
No. 1, August 11979 ; Research Disclosure ,
No. 18716, November 1979; Research Disclosure
Ja, No. 22534, January 1983; research de
Office closures, No. 308119, December 1989, and in Research Disclosure, No. 36544, 19
It can be found in September 1994.

The silver halide photographic material can be exposed and developed by conventional processing techniques. Dihydroxybenzene (eg, hydroquinone), pyrazolidone (1-phenyl-3-pyrazolidone or 4,4-dimethyl-1-phenyl-3)
-Pyrazolidone) and aminophenols (eg, N-
Known developers such as methyl-p-aminophenol) can be added to the developer either alone or in combination. Preferably, the silver halide photographic material is developed in a developer containing dihydroxybenzene as the primary developer and pyrazolidone and p-aminophenol as auxiliary developers. For example, anti-fogging agents (benzotriazole, indazole, tetrazole), silver halide solvents (silver halide thiosulfate, silver halide thiocyanate), sedimentation inhibitors (aminopolycarboxylic acid, aminopolyphosphonic acid), sulfites Antioxidants, buffers, inhibitors, curing agents, contrast enhancers,
Other well-known additives, such as surfactants and the like, may be included in the developer. An inorganic alkaline agent such as KOH, NaOH and LiOH is added to the developer composition to obtain a desired pH (usually pH 10 or more).

The silver halide photographic material can be developed using a fixing agent having a usual composition for the required use. Suitable fixing agents include thiosulfate, thiocyanate, sulfite, ammonium salts and the like. The fixer composition can include other well-known additives such as, for example, acid compounds (metabisulfate), buffers (carboxylic acid, acetic acid), hardeners (aluminum salts), tone improvers, and the like.

The exposed radiographic material can be developed by conventional development techniques. Such a development technique is described in the aforementioned
Research Disclosure , No. 17643, 1978
December; and Research Disclosure , No. 36
No. 544, September 1994. U.S. Patent No.
No. 3,025,779; No. 3,515,556; No. 3,545,97
No. 1 and 3,647,459, and British Patent No.
The roller transfer development described in Japanese Patent No. 1,269,268 is particularly preferred. The curing development described in U.S. Pat. No. 3,232,761 can also be used.

A method for preparing a silver halide emulsion,
Literature on the use of certain components in emulsions and photosensitive elements can be found in Research Disclosure , No. 38.
No. 957, September 1996, especially in the following chapters: I. Emulsion particles and their preparation II. Vehicles, vehicle extenders, vehicle-like auxiliaries and vehicle-related auxiliaries III. Emulsion cleaning IV. Chemical sensitization Spectral sensitization and sensitivity suppression VI. UV dye / fluorescent brightener / fluorescent dye VII. Anti-fogging agents and stabilizers VIII. Absorbing and scattering substances IX. Coating physical property modulation aid X. Dye image formers and modulators XI. Layer and layer arrangement XV. Support

[0055]

The present invention is described in detail in the following non-limiting examples. The amounts described in the following examples are all
Unless otherwise specified, the amount is based on 1 mol of silver in the obtained silver halide emulsion. Example 1 Sample 1 (control sample): average particle size 1.25 μm, average particle thickness 0.
A silver iodobromide emulsion having a thickness of 18 μm, a COV of 37% and an iodide content of 0.9 mol% based on the total halide ions was prepared by a double jet method. The emulsion is
Sulfur sensitizer, gold sensitizer, mercury sensitizer, and palladium sensitizer, and 5,5'-dichloro-9-ethyl-3,3'-di- (3-sulfopropyl) as a spectral sensitizing dye Chemical sensitization and spectral sensitization were performed using triethylammonium salt of oxacarbocyanine. The above emulsion at 60 ° C for about 120
After digestion for ~ 130 minutes, before cooling, add potassium iodide 200
mg and 1366 mg of 5-methyl-7-hydroxy-2,3,4-triazoindolizine (4-hydroxy-6-methyl-1,3,3a, 7-tetraazaindene). The sensitized silver halide emulsion was melted at 45 ° C. and subjected to an experimental coating test. As a coating aid, about 1293 mg of calcium nitrate,
Azodicarboxylic acid dimorpholide 80 mg, polyethyl acrylate (20% dispersion in a mixture of water / lauryl sulfate 367 mg) 18338 mg, dextran as gel extender [Pharmacosmos] 66736
mg, Colanyl blue (registered trademark) as a chromaticity adjuster
267 mg [produced by Hoechst Chemical Company] was added. The pH was adjusted to 6.3 before adding 3774 mg of the SSMA copolymer [styrene sulfonic acid and maleic anhydride copolymer, Aquaness Corp., Texas, USA].

The resulting silver halide emulsion was immediately applied to two sides of a blue 7 miL thick polyester support coated with a conventional antistatic topcoat containing a hardener. The coating speed was 8.3 m / min and the silver coating weight was about 2.25 g per side. New film sample
Hold at 38 ° C. for 3 days before subjecting to iron (III) impurities. On one side of this sample, iron sulfate: Fe ₂ (S
O ₄ ) ₃ 0.1% by weight, 1% by weight of standard gelatin as a coating aid (manufactured by Deutsche Gelatin Fabril AG, Germany) and Triton® X1 as a surfactant
The solution containing 0.12% by weight is 11.4 m ² per m ²
L was applied. This solution was applied to Meyer Bar No. 5
Was applied to half of one side of a 10 cm × 28 cm sample. According to this method, a predetermined standard impurity can be contained, and a compound capable of removing a defect caused by the impurity can be identified. Triton (registered trademark) is an alkylphenoxyethylene-based nonionic surfactant represented by the following formula.

Embedded image

The obtained impurity-containing film was dried,
Using an o.8 filter, exposure was performed for 3/10 seconds with white light equipped with a standard bromograph.

The exposed film was used as a standard reagent: XAD3
It was developed for 90 seconds by a dry medical X-ray film automatic developing machine (manufactured by Imation Corporation, Minnesota, U.S.A.) using a developer and an XAF3 fixer (both manufactured by Imation Corporation, Minnesota, U.S.A.). . The optical density was measured in both the region containing no impurity and the region containing the impurity, and the sensitivity suppressing effect of iron (III) was determined using the following equation.

## EQU1 ## ΔD = (D1-D2) × 100 / D2 (where D1 is the impurity-containing region of the sample)
D2 represents the average of the ten concentration measurements and D2 represents the average of the ten concentration measurements in the impurity-free region of the same sample. )

The value (%) of ΔD is negative when there is a sensitivity suppressing effect, and positive when there is a sensitizing effect. Also, the value (%) of ΔD is proportional to the effect of iron (III) in the final material, which is not speckle protected. Table 1 shows the results.

Sample 2 (invention): 5 g of compound 1 (2,5-dihydroxybenzenesulfonic acid potassium salt) at the end of addition of the coating sample (this corresponds to 0.0219 mol of said compound per mol of silver, and Coated film 1
This corresponds to 209 mg per m ² . ) The procedure of Sample 1 was repeated except that it was added. An iron impurity adding step was performed on a half area of one side of the obtained sample in the same procedure as in the above-mentioned sample 1, and the protective effect of compound 1 was determined. Table 1 shows the results.

Sample 3 (invention): 7.55 g of compound 2 (2,5-dihydroxy-1,4-benzenedisulfonic acid dipotassium salt) at the end of the addition of the coating sample (0.0218 g of the compound per mol of silver) Equivalent to mol and equivalent to 315 mg / m ^{2 of} coated film.) The procedure of sample 1 was repeated, except that it was added. An iron impurity adding step was performed on a half area of one side of the obtained sample in the same procedure as in the above-mentioned sample 1, and the protective effect of compound 1 was determined. Table 1 shows the results.

[0062]

[Table 1]

Example 2 Sample 4 (Control Sample):
After holding for days, cubic nitrate: Cu (NO
₃ ) ₂ 0.5% by weight, 1% by weight of standard gelatin as a coating aid [manufactured by German Gelatin Fabrik Actiengezelshaft, Germany] and Triton X as a surfactant
Sample ¹ was prepared except that 11.4 mL / m ^{2 of} a solution containing 0.12% by weight of 100 was applied to one half of one side of a 10 cm × 28 cm sample using a Meyer bar No. 5 and subjected to copper (II) impurities.
Procedure was repeated. Table 2 shows the results.

Sample 5 (invention): 5 g of compound 1 (potassium 2,5-dihydroxybenzenesulfonate ) at the end of the addition of the coating sample (this corresponds to 0.0219 mol of said compound per mol of silver, and Coated film 1
This corresponds to 209 mg per m ² . 2) The procedure of Sample 4 was repeated except that the addition was performed, and an iron impurity adding step was performed on a half area of one side of the obtained sample to determine the protective effect of Compound 1. Table 2 shows the results.

Sample 6 (invention): 7.55 g of compound 2 (2,5-dihydroxy-1,4-benzenedisulfonic acid dipotassium salt) at the end of the addition of the coating sample (this is 0.0218 g of the compound per mol of silver). corresponds to a molar, and corresponds to the coated film 1 m ² per 315 mg.) was added than ever by repeating the procedure of sample 4, performs the resulting iron impurity doping process to half of the one surface of the sample, The protective effect of compound 2 was determined. Table 2 shows the results.

[0066]

[Table 2] From the results of Samples 5 and 6, it is clear that the aryl compounds of the present invention can reduce the negative effects of copper (II).

Example 3 Sample 7 (control sample): A sample was prepared in the same manner as in Sample 1. Table 3 shows the results.

Sample 8 (invention): 2 g of Compound 3 (2,5-dihydroxy-1,3-benzenedisulfonate disodium salt) at the end of addition of the coating sample (this is 0.0064% of the above compound per mole of silver) corresponds to a molar, and corresponds to the coated film 1 m ² per 83 mg.) was added than ever in the same manner to the procedure of sample 7, was determined the protective effect of compound 3. Table 3 shows the results.

Sample 9 (invention): 4 g of compound 3 (2,5-dihydroxy-1,3-benzenedisulfonate disodium salt) was added at the end of the addition of the coating sample (this was 0.0128 per mole of silver). corresponds to a molar, and corresponds to the coated film 1 m ² per 166 mg.) was added than ever in the same manner to the procedure of sample 7, was determined the protective effect of compound 3. Table 3 shows the results.

Sample 10 (invention): 8 g of Compound 3 (2,5-dihydroxy-1,3-benzenedisulfonate disodium salt) was added at the end of addition of the coating sample (this was
This corresponds to 0.0256 mol of the compound per mol and 333 mg / m ^{2 of the} coated film. ) The protective effect of Compound 3 was determined in the same manner as for Sample 7, except for the addition. Table 3 shows the results.

Sample 11 (invention): 2.21 g of compound 2 (dipotassium 2,5-dihydroxy-1,4-benzenedisulfonate) was added at the end of addition of the coating sample.
This corresponds to 0.0064 moles of the compound per mole and 92 mg / m ^{2 of} coated film. ) The protective effect of Compound 2 was determined in the same manner as in the procedure of Sample 7, except for the addition. Table 3 shows the results.

Sample 12 (invention): 4.42 g of compound 2 (dipotassium 2,5-dihydroxy-1,3-benzenedisulfonate) (final silver 1
This corresponds to 0.0128 mol of the compound per mol and 184 mg / m ^{2 of} coated film. ) The protective effect of Compound 2 was determined in the same manner as in the procedure of Sample 7, except for the addition. Table 3 shows the results.

Sample 13 (invention): 8.85 g of Compound 2 (dipotassium salt of 2,5-dihydroxy-1,3-benzenedisulfonate) was added at the end of the addition of the coating sample (this corresponds to silver 1
This corresponds to 0.0256 moles of the compound per mole and 369 mg / m ^{2 of} coated film. ) The protective effect of Compound 2 was determined in the same manner as in the procedure of Sample 7, except for the addition. Table 3 shows the results.

[0074]

[Table 3] Control sample 7 has 0.06 mmol / m ² of iron (III) on the sample.
Shows the effect of suppressing sensitivity. On the other hand, samples 8 to
13, the aryl compound of the present invention shows that iron (II)
It is clear that the negative effects of I) can be reduced.

Sample 14 (control sample): A coating sample was prepared by using iron sulfate: Fe (SO ₄ ) ₃ 0.1 wt% as an iron source,
1% of standard gelatin as a coating aid [Germany, Georg, Fabrik, Actiengezelshaft, Germany]
0.12% by weight Triton X100 as weight and surfactant
Using a Mayer bar No.10 solution 23 mL / m ² containing iron and applied to the sample one side half of the 10 cm × 28cm (II
I) The procedure for sample 1 was repeated, except that it was subjected to impurities. Table 4 shows the results.

Sample 15 (invention): 2 g of compound 3 (disodium salt of 4,5-dihydroxy-1,3-benzenedisulfonate) (2 g of silver 1
It corresponds to 0.0064 mol of the compound per mol and to 83 mg / m ^{2 of} coated film. ) The protective effect of compound 3 was determined in the same manner as in the procedure for sample 14, except that it was added. Table 4 shows the results.

Sample 16 (invention): 4 g of Compound 3 (4,5-dihydroxy-1,3-benzenedisulfonate disodium salt) was added at the end of the addition of the coating sample.
This corresponds to 0.0128 mol of the compound per mol and 166 mg per m ^{2 of} coated film. ) The protective effect of compound 3 was determined in the same manner as in the procedure for sample 14, except that it was added. Table 4 shows the results.

Sample 17 (invention): 8 g of compound 3 (disodium salt of 4,5-dihydroxy-1,3-benzenedisulfonate) (8 g of silver 1
This corresponds to 0.0256 mol of the compound per mol and 333 mg / m ^{2 of the} coated film. ) The protective effect of compound 3 was determined in the same manner as in the procedure for sample 14, except that it was added. Table 4 shows the results.

Sample 18 (invention): 2.21 g of Compound 2 (dipotassium 2,5-dihydroxy-1,4-benzenedisulfonate) was added at the end of addition of the coating sample.
This corresponds to 0.0064 moles of the compound per mole and 92 mg / m ^{2 of} coated film. ) The protective effect of compound 3 was determined in the same manner as in the procedure for sample 14, except that it was added. Table 4 shows the results.

Sample 19 (Invention): 4.42 g of Compound 2 (dipotassium 2,5-dihydroxy-1,4-benzenedisulfonate) was added at the end of the addition of the coating sample.
This corresponds to 0.0128 mol of the compound per mol and 184 mg / m ^{2 of} coated film. ) The protective effect of compound 2 was determined in the same manner as for sample 14, except that it was added. Table 4 shows the results.

Sample 20 (invention): 8.85 g of compound 2 (2,5-dihydroxy-1,4-benzenedisulfonic acid dipotassium salt) was added at the end of the addition of the coating sample.
This corresponds to 0.0256 moles of the compound per mole and 368 mg / m ^{2 of} coated film. ) The protective effect of compound 2 was determined in the same manner as for sample 14, except that it was added. Table 4 shows the results.

[0082]

[Table 4] Control sample 14 had 0.12 mmol / iron (III) on the sample.
The sensitivity suppression effect of m ² is shown. In contrast, the results of Samples 15 to 20 of the present invention show that a positive effect is exhibited when the aryl compound of the present invention contains a high proportion of impurities.

Example 5 Sample 21 (control sample):
After holding for days, copper nitrate: Cu (NO ₃ ) ₂ as a copper source
0.125% by weight, standard gelatin as coating aid [manufactured by German Gelatin Fabrik Actiengezelshaft,
Germany] 1% by weight and Triton X100 as surfactant
11.4 mL / m ^{2 of} a solution containing 0.12% by weight
The procedure for Sample 1 was repeated, except that bar 10 was used to coat one half of a 10 cm x 28 cm sample on one side and was exposed to copper (II) impurities. Table 5 shows the results.

Sample 22 (invention): 2 g of compound 3 (4,5-dihydroxy-1,3-benzenedisulfonate disodium salt) (the amount of silver 1
It corresponds to 0.0064 mol of the compound per mol and to 83 mg / m ^{2 of} coated film. ) The protective effect of Compound 3 was determined in the same manner as for Sample 21, except for the addition. Table 5 shows the results.

Sample 23 (invention): 4 g of compound 3 (disodium salt of 4,5-dihydroxy-1,3-benzenedisulfonate) (4 g of silver 1
This corresponds to 0.0128 mol of the compound per mol and 166 mg per m ^{2 of} coated film. ) The protective effect of Compound 3 was determined in the same manner as for Sample 21, except for the addition. Table 5 shows the results.

Sample 24 (invention): 8 g of compound 3 (disodium salt of 4,5-dihydroxy-1,3-benzenedisulfonate) (8 g of silver 1
This corresponds to 0.0256 mol of the compound per mol and 333 mg / m ^{2 of the} coated film. ) The protective effect of Compound 3 was determined in the same manner as for Sample 21, except for the addition. Table 5 shows the results.

Sample 25 (invention): 2.21 g of Compound 2 (2,5-dihydroxy-1,4-benzenedisulfonic acid dipotassium salt) at the end of addition of the coating sample, equivalent to 0.0064 mol of the above compound per mol of silver And corresponds to 92 mg / m ^{2 of} coated film. ) The protective effect of Compound 2 was determined in the same manner as in the procedure of Sample 21, except for the addition. Table 5 shows the results.

Sample 26 (invention): At the end of addition of the coating sample, 4.42 g of Compound 2 (2,5-dihydroxy-1,4-benzenedisulfonic acid dipotassium salt), equivalent to 0.0128 mol of the above compound per mol of silver And 184 mg / m ^{2 of} coated film. ) The protective effect of Compound 2 was determined in the same manner as in the procedure of Sample 21, except for the addition. Table 5 shows the results.

Sample 27 (invention): 8.85 g of Compound 2 (dipotassium 2,5-dihydroxy-1,4-benzenedisulfonate) at the end of addition of the coating sample, equivalent to 0.0256 mol of the above compound per mol of silver And 368 mg / m ^{2 of} coated film. ) The protective effect of Compound 2 was determined in the same manner as in the procedure of Sample 21, except for the addition. Table 5 shows the results.

[0090]

[Table 5] Control sample 21 was 0.48 mmol / m2 copper (II) on the sample.
² shows the effect of suppressing sensitivity. In contrast, sample 2 of the present invention
From the results of 2 to 27, it is clear that the aryl compound of the present invention can reduce the negative effect of copper (II).

Example 6 Sample 28 (control sample): Emulsion containing impurities 7
The procedure of Sample 1 was repeated, except that it was applied to two sides of a miL thick blue polyester film substrate. The impurities were fine particles of iron and copper generated during the manufacturing process of the base material. Further, the prepared film sample was subjected to 3 ° C at 38 ° C.
After holding for days, the samples were exposed to white light equipped with a standard bromograph for 3/10 seconds using Filter No. 5. Microscopic observation of the developed material determined the number of spot defects that appeared on the film sample. This defect is 10cm x 28cm
Were measured for six samples, and the average value was obtained. Table 6 shows the results.

Sample 29 (invention): 1.895 g of compound 2 (2,5-dihydroxy-1,4-benzenedisulfonic acid dipotassium salt) at the end of addition of the coating sample, equivalent to 0.00548 mol of the above compound per mol of silver And 78.9 mg / m ^{2 of} coated film. ) The protective effect of compound 2 was determined in the same manner as for sample 28 except for the addition. Table 6 shows the results.

Sample 30 (invention): At the end of addition of the coating sample, 3.771 g of compound 2 (2,5-dihydroxy-1,4-benzenedisulfonic acid dipotassium salt), equivalent to 0.0109 mol of the above compound per mol of silver And 157 mg / m ^{2 of} coated film. ) The protective effect of compound 2 was determined in the same manner as for sample 28 except for the addition. Table 6 shows the results.

Sample 31 (Invention): 7.543 g of Compound 2 (2,5-dihydroxy-1,4-benzenedisulfonic acid dipotassium salt) at the end of addition of the coating sample, equivalent to 0.0218 mol of the above compound per mol of silver And 314 mg / m ^{2 of} coated film. ) The protective effect of compound 2 was determined in the same manner as for sample 28 except for the addition. Table 6 shows the results.

[0095]

[Table 6] Control sample 28 exhibited a large number of spot defects due to iron and copper impurities during film substrate preparation. In contrast, the results of samples 29-31 of the present invention demonstrate that the aryl compounds of the present invention can significantly reduce the number of defects. Therefore, the aryl compound of the present invention can effectively prevent regulation of spot defects in a film prepared using a substrate containing a very high concentration of impurities.

[0096]

In the method of the present invention, by adding a specific aryl derivative during the preparation of the silver halide emulsion contained in the silver halide photographic material, it is possible to reduce the amount of metallic impurities generated during the preparation of the support. Spot defects can be reduced and prevented.

Continued on the front page (72) Inventor Alan Simondi Dominic Italy, 1707-1 Ferrania (Savona), within Imation Riccierque Societa per Acioni (72) Inventor Giuseppe Roviglio, Italy, 1706-1 Ferrania (Savona), within Imation Richerque Societa per Acioni

Claims (6)

[Claims] (1) a step of preparing a silver halide emulsion; (b) a step of chemically or optically sensitizing the silver halide emulsion; (c) at least two hydroxyl groups and a sulfonic acid group; (D) adding an aryl compound having at least one substituent represented by a hydroxyl group, a carboxyl group or a hydroxymethyl group to the silver halide emulsion in an amount of less than 0.03 mol per mol of silver; A method for producing a silver halide photographic material, comprising a step of applying a silver emulsion to a support. 2. The method according to claim 1, wherein the aryl compound has the formula: (Wherein, R _{1 to} R ₄ are each selected from the group consisting of a hydrogen atom, a sulfonic acid group, a hydroxyl group, a carboxyl group and a hydroxymethyl group, but at least one of R _{1 to} R ₄ is not a hydrogen atom 2. The method according to claim 1, wherein the method is represented by: 3. A silver halide emulsion comprising an aryl compound having at least two hydroxyl groups and at least one substituent represented by a sulfonic acid group, a hydroxyl group, a carboxyl group or a hydroxymethyl group in an amount of 0.03 / mol of silver. A silver halide emulsion free of metal impurities, characterized in that it is contained in an amount of less than mol. 4. A silver halide photographic material comprising a support coated with at least one silver halide emulsion layer, said silver halide emulsion layer comprising at least two hydroxyl groups, a sulfonic acid group, a hydroxyl group, A silver halide photographic material comprising an aryl compound having at least one other substituent represented by a carboxyl group or a hydroxymethyl group in an amount of less than 0.03 mol per mol of silver. 5. The method according to claim 1, wherein the aryl compound has the formula: (Wherein, R _{1 to} R ₄ are each selected from the group consisting of a hydrogen atom, a sulfonic acid group, a hydroxyl group, a carboxyl group, and a hydroxymethyl group, but at least one of R _{1 to} R ₄ is not a hydrogen atom 5. The silver halide photographic material according to claim 4, which is represented by the formula: 6. The silver halide photographic material according to claim 4, wherein said silver halide emulsion is a columnar grain silver halide emulsion having an aspect ratio of at least 2: 1 which is a ratio of average grain size to thickness.