JP2903450B2 - Silver halide photographic material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a silver halide photosensitive material used for plate making.

[0002]

2. Description of the Related Art In recent years, in the field of printing and plate making, many devices for outputting a film using a laser such as a color separation scanner or an image setter or an LED light source have been developed.
Regarding the light source wavelength, an argon (Ar) laser has been shifted to a longer wavelength helium-neon (He-Ne) laser or LED because the light source is inexpensive. Also,
The exposure format has changed from an outer surface scanning type to an inner surface or planar scanning type. The longer the light source wavelength is, the harder it is to converge the inner surface or planar scanning compared to the outer surface scanning. Is blurred, and a high-contrast image cannot be obtained.

[0003]

Heretofore, in order to solve such a problem, a filter dye has been used as one means to cut off blurred light. However, such filter dyes generally have a decrease in sensitivity, so that a large amount of sensitizing dye is used, and as a result, the residual color of the film is remarkable.

An object of the present invention is to provide a silver halide light-sensitive material having high sensitivity and little residual color.

[0005]

An object of the present invention is to provide a silver halide light-sensitive material having at least one silver halide emulsion layer, wherein at least one of the silver halide light-sensitive materials has the following formula: , Containing at least one selected from the compounds represented by the general formulas [1] to [5], which have specified the structural parameters described in [Chemical formula 2], and represented by the following general formula [6] The problem has been solved by a silver halide light-sensitive material characterized by containing at least one compound represented by the formula:

In the present invention, R ₁ , R ₂ , R ₃ , R ₄ and R _{5 in the} general formula [ ₁ ] and Z ₁ , Z ₂ , Z ₃ , Z ₄ and Z ₄ in the general formula [2] are used. It is preferable that at least three or more of the substituents of ₅ and Z ₆ are water-soluble organic groups.

Hereinafter, the present invention will be described specifically.

First, general formulas [1] and [2] will be described.

In the general formula [1], at least two of R _{1 to} R ₅ and Z _{1 to} Z ₅ in the general formula [2] represent an organic group carrying a water-soluble group. "
The term refers to a compound having a negative π value in the Hansch method used in a so-called structure-activity relationship that captures the relationship between the structure and the physiological activity of a compound. For the Hansch method, refer to J. Me.
d. Chem, 16, 1207 (1973) and 20, 304 (1979).

Among these water-soluble groups, dyes which are ionized in an aqueous solution and have two or more dyes having a pKa of 4 or more and 11 or less are preferable. Particularly preferably, two or more are 4 to
The organic group having a pKa of 11 and at least one of which has a pKa of 4 or less has characteristics of excellent spectral sensitivity and low residual color contamination.

Examples of specific functional groups exhibiting preferable pKa are shown below, but the present invention is not limited to these.

[0012] pKa those _{4~11 - (CH 2) nCOOM,} -C 6 H 4 COOM, -CH 2 C 6 H
_{4 COOM, -CH 2 -CH = CH} -CH 2 COOM, -
_{(CH 2) 2 SO 2 NHC} 6 H 4, -CH 2 CH 2 CONH 2 pKa of 4 or less things _{- (CH 2) nSO 3 M} , -C 6 H 4 SO 3 M, -CH 2 C 6 H 4
_{SO 3 M, -CH 2 CH =} CH-CH 2 SO 3 M, CH 2 C
H (SO ₃ M) CH _{3 In the} above formula, n represents 2 to 4, and M represents a hydrogen atom, an alkali metal atom or an ammonium group, or an organic amine group.

R ₁ , which does not represent an organic group having a water-soluble group,
R ₅ and Z _{1 to} Z ₆ may be hydrogen, alkyl groups such as methyl and ethyl groups, substituted alkyl groups, alkenyl groups such as aryl groups, substituted alkenyl groups, aryl groups such as phenyl groups, or substituted aryl groups such as p-tolyl Selected from the group

R ₆ and R ₇ in the general formula [1] and Z ₇ and Z ₈ in the general formula [2] are the same or different, and are each a hydrogen, a hydroxy group, a halogen atom, an alkyl group (for example, methyl, ethyl and Propyl), substituted alkyl (eg, trifluoromethyl and 2,2,2-trifluoroethyl), alkenyl (eg, allyl), substituted alkenyl, alkoxy (eg, methoxy and ethoxy), alkylthio (For example, an ethylthio group),
Substituted alkylthio, arylthio (eg, phenylthio), substituted arylthio, aryl (eg, phenyl), substituted aryl (eg, p-tolyl), acyl (eg, acetyl and propionyl), acyloxy (eg, acetoxy) And propionyloxy groups), alkoxycarbonyl groups (eg, methoxycarbonyl and ethoxycarbonyl groups), alkylsulfonyl groups (eg, methylsulfonyl groups, carbamoyl groups), substituted carbamoyl, amide groups, substituted amide groups, sulfamoyl groups, substituted sulfamoyl groups, sulfones It represents an amide group, a substituted sulfonamide group, a carboxy group and a cyano group. Or R ₆ and R ₇ are linked, and Z ₇ and Z ₈ are linked to represent the atoms necessary to complete a carbocyclic ring system such as a benzene or naphthalene ring system, which may be the same or different.
And it may carry one or more of the substituents selected from the substituents shown for R ₆ and R ₇ and Z ₇ and Z ₈ respectively.

Hereinafter, specific examples of the compounds represented by the general formulas [1] and [2] will be given.

[0016]

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[0017]

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[0018]

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[0019]

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[0020]

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Next, the general formula [3] will be described.

In the above general formula [3], Y ₁ and Y ₂ each represent a nonmetallic atom group necessary for forming a benzothiazole ring, a benzoselenazole ring, a naphthothiazole ring, a natetoselenazole ring or a quinoline ring. And these heterocycles are a lower alkyl group (eg, methyl group, ethyl group, etc.), an alkoxy group (eg, methoxy group, ethoxy group, etc.), a hydroxyl group, an aryl group (eg, phenyl group), an alkoxycarbonyl group (eg, methoxycarbonyl group) Group), a halogen atom (eg, a chlorine atom, a bromine atom, etc.) and the like. R ₁ and R _{2 each} represent a lower alkyl group (eg, a methyl group, an ethyl group, a propyl group, a butyl group, etc.), an alkyl group having a sulfo group (eg, a β-sulfoethyl group,
γ-sulfopropyl group, γ-sulfobutyl group, δ-sulfobutyl group, sulfoalkoxyalkyl group; for example, sulfoethoxyethyl group, sulfopropoxyethyl group, etc., and alkyl group having a carboxyl group (eg, β-
Carboxylethyl group, γ-carboxypropyl group, γ-
Carboxybutyl group, δ-carboxybutyl group, etc.). R ₃ represents a methyl group, an ethyl group, or a propyl group.
X ₁ represents an anion (eg, a halogen ion, a benzenesulfonate ion, a p-toluenesulfonate ion, etc.) commonly used for cyanine dyes. m represents 1 or 0, and when it is an inner salt, m = 0.

Specific examples of the compound represented by the above general formula [3] are shown below. However, the compounds used in the present invention are not limited to these.

[0024]

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[0025]

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[0026]

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[0027]

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[0028]

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[0029]

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[0030]

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[0031]

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[0032]

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[0033]

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Next, the general formula [4] will be described.

In the formula, R and R ₁ each represent an alkyl group (having 1 to 10 carbon atoms, preferably 1 to 5 carbon atoms) or a substituted alkyl group (having 1 to 10 carbon atoms in the alkyl portion, preferably 1 to 5, for example, an alkyl group containing a sulfo group (preferably having an alkyl radical (moiely) having 1 to 4 carbon atoms), hydroxy, acetoxy or alkoxy (the alkyl radical preferably has 1 carbon atom).
To 4) and an alkyl group substituted with a sulfo group, a sulfoaralkyl group or an alkyl group containing a carboxyl group (preferably an alkyl radical (moiely) having 1 to 4 carbon atoms).
), An alkyl-substituted aralkyl group, an alkoxy-substituted aralkyl group, a halogen-substituted aralkyl group, an aryloxyalkyl group, an alkyl or alkoxy-substituted aryloxyalkyl group, an aryl group (preferably having 4 to 15 carbon atoms), a substituted aryl group (The aryl moiety has 4 to 15 carbon atoms.
Are preferable, and as the substituent, a substituent of a substituted alkyl group is used. ) Represents an allyl group.

At least _one of R and R ₁ represents an alkyl group containing a sulfo group or an alkyl group containing a carboxyl group.

R ₂ and R ₃ each represent an alkyl group (preferably having 1 to 5 carbon atoms, such as a methyl group, an ethyl group, and a propyl group).

Z represents a group of nonmetallic atoms necessary for completing a 5- or 6-membered nitrogen-containing heterocyclic nucleus together with a nitrogen atom. Examples of the heterocyclic nucleus include a thiazole nucleus, a selenazole nucleus, an oxazole nucleus, and a quinoline nucleus. , 3,3-dialkylindolenine nucleus, imidazole nucleus, pyridine nucleus and the like. Of these, thiazole nuclei and oxazole nuclei are preferably used advantageously. More preferably, a benzothiazole nucleus, a naphthothiazole nucleus and a naphthoxazole nucleus are advantageously used.

Next, typical examples of the dye represented by the general formula [4] are shown below.

[0040]

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[0041]

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[0042]

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[0043]

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Next, specific examples of the compound represented by the general formula [5] are shown.

[0045]

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To use the sensitizing dyes represented by the general formulas [1] to [5] in a silver halide emulsion, the sensitizing dyes are added to a coating solution and dissolved, or are dissolved in water or methanol, ethanol,
It may be added by dissolving in an organic solvent such as acetone alone or a mixed solvent thereof. Further, it may be added in a powder state. However, if necessary, a layer adjacent to the silver halide emulsion layer, for example, a protective layer or an intermediate layer may be added as long as the photographic performance is not affected.

The amount of the sensitizing dye used in the present invention when it is added to the silver halide emulsion varies depending on the type of the silver halide emulsion and the type of the sensitizing dye. The range of 5 × 10 ^{-6 to} 2 × 10 ^-1 mol is preferred.

Next, specific examples of the compound represented by the general formula [6] will be given. However, the compounds used in the present invention are not limited to these.

[0049]

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[0050]

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In the chemical sensitization of the present invention, gold,
It is particularly preferable to use a sensitizer based on a noble metal such as platinum. Examples of these noble metal sensitizers include, for example, gold sensitizers (US Pat. Nos. 2,540,085, 2,597,876, and 2,399,
083), sensitization with a Group VIII metal ion compound (US Pat. Nos. 2,448,060, 2,540,086, and 2,566,245)
No. 2,566,263 and No. 2,598,079). In addition, in the present invention, a reduction sensitizer (US Pat.
Nos. 518,698, 2,419,974, and 2,983,610).

In the silver halide emulsion (hereinafter sometimes simply referred to as emulsion) used in the present invention, for example, silver chloride is used as silver halide in an amount of 50 mol% or more, preferably 55 to 90 mol%.
A silver chlorobromide emulsion or a silver chloroiodobromide emulsion containing mol% is preferably used, but is preferably a monodisperse emulsion having a coefficient of variation (%) of 20 or less, and a grain size of 3 μm or less, particularly preferably 0.1 to 1 μm. . The coefficient of variation (%) used the definition described in JP-A-62-32444.

In the emulsion of the present invention, 10 ^-5 to 10 ^-10 mol, preferably 10 ^-10 mol, per mol of silver halide is required until the completion of grain formation.
It is preferable to contain ^-6 to 10 ^-9 mol of a rhodium salt (including a complex salt). As such a rhodium salt, conventionally known rhodium salts are arbitrarily used.
₃ [RhCl ₆ ], K ₃ [RhBr ₆ ], rhodium chloride ammine complex, rhodium trichloride and the like are used.

In addition to the rhodium salt, the emulsion of the present invention is selected from cadmium salt, zinc salt, lead salt, thallium salt, iridium salt (including complex salt) and iron salt (including complex salt) by the end of grain formation. At least one of them.

The silver halide is generally subjected to desalting after physical ripening in order to remove unnecessary salts. As a method of desalting, a method such as gelation dialysis, or a method such as salting out with a water-soluble sulfate or the like can be used.However, the coagulation method using a modified gelatin or an acrylic acid-based polymer is described above. The use of the desalting method and the sensitization method of the present invention has a particularly large effect of suppressing fog, and is a preferable desalting method.

Examples of the modified gelatin include, for example,
Compounds described in 3-324968 are exemplified.

The acrylic acid-based polymer includes
For example, JP-B-47-17854, JP-A-52-67318, JP-A-3-
No. 288143.

The silver halide photographic material of the present invention can have a hydrophilic colloid layer in addition to at least one silver halide emulsion layer. Further, the support may have at least one hydrophilic colloid layer on the side opposite to the silver halide emulsion layer.

The hydrophilic colloid contained in the silver halide emulsion layer and the hydrophilic colloid layer includes gelatin (which may be treated with coal or acid), a gelatin derivative, a polymer graft compound of gelatin, and a synthetic hydrophilic polymer compound. In the silver halide photographic light-sensitive material of the present invention, gelatin is preferred.

The silver halide photographic light-sensitive material of the present invention can be used, as a toning agent, a hydrazine compound described in JP-A-56-106244 or a tetrazolium compound described in JP-A-57-132137. Can be used.

Various conventional techniques, additives and the like can be used for the silver halide emulsion of the present invention.

For example, various chemical sensitizers, color toning agents, hardeners, surfactants, thickeners, etc. may be added to the silver halide photographic emulsion and other hydrophilic colloid layers used in the present invention, if necessary. A plasticizer, a slipping agent, a development inhibitor, an ultraviolet absorber, an anti-irradiation dye, a matting agent and the like can be further contained by various methods. The silver halide photographic emulsion of the present invention and other hydrophilic colloid layers may contain a polymer latex.

These additives are described in more detail in Research Disclosure, Vol. 176, Item 17643 (December, 1978) and 187, Item 18716, (November, 1979). It is shown together.

Additive Type RD17643 RD18716 Chemical sensitizer page 23 648 right column 2. Sensitivity increasing agent Same as above 3. Supersensitizer page 649, right column to 650 column Brightener page 24 5. 5. Antifoggant and stabilizer page 24 to 25 page 649, right column Light absorber Filter dye UV absorber Page 25-26 Page 649 Right column-7. 7. Stain inhibitor 25 pages right column 650 pages left to right column 8. Dye image stabilizer page 25 Hardening agent Page 26 651 Left column 10. Binder page 26 Same as above 11. Plasticizers, lubricants Page 27, 650 right column 12. Coating aids, surfactants 26-27 Same as above 13. Examples of the support that can be used in the silver halide photographic light-sensitive material of the present invention include cellulose acetate, cellulose nitrate, and the like.
Examples thereof include polyester such as polyethylene terephthalate, polyolefin such as polyethylene, polyethylene, baryta paper, paper coated with polyolefin, glass, and metal. These supports are subjected to a base treatment as required.

The silver halide photographic light-sensitive material according to the present invention can be subjected to development processing after exposure by various methods, for example, a commonly used method.

[0066]

EXAMPLES The present invention will be described below in detail with reference to examples, but embodiments of the present invention are not limited thereto.

Example 1 << Preparation of Silver Halide >> pAg = 7.
7. Maintain pH = 3.0, mixing temperature 40 ℃, halogen composition AgC
A silver halide emulsion having an l / Br = 70/30 and an average grain size of 0.36 μm was obtained. During the mixing step from the formation of 5% of the final attained average particle size to the final attained average particle size, potassium hexabromorhodate and potassium hexachloroiridate were added at 1.5 × 10 ^-8 and 4 ×, respectively, per mole of silver. 10 ^-7
Mole was added. The emulsion thus obtained was added with 15 g of denatured gelatin treated with phenyl isocyanate per mol of silver, washed with water three times at pH = 4.4 and washed with water.

After adjusting the pH of these emulsions to 5.8 and pAg = 7.0 using citric acid and sodium chloride, chloroauric acid was added in an amount of 2 × 10 ^-2 mol per mol of silver, and the polysulfide compound (sulfuric acid) was added in silver. Add 2 mg per mole and add 12 mg at 60 ° C.
It was chemically ripened for 0 minutes to reach the highest sensitivity. Thereafter, 1-phenyl-5-mercaptotetrazole and 4-hydroxy-6-methyl-1,3,3a, 7-tetrazaindene were added at 350 mg and 2540 mg per mol of silver, respectively, and the operation was stopped.

To the emulsion thus obtained (hereinafter referred to as per mol of silver unless otherwise specified), 1.2 g of potassium bromide was added, and the dyes represented by the general formulas [1] to [5] were added. (Table 1), and the compound of the general formula [6] was further added.

10% of hydroquinone as antifoggant
50 ml of a methanol solution, 10 ml of a 2% aqueous solution of phenidone in methanol, and 19 ml of a 20% aqueous saponin solution as a spreading agent.
ml, 4% of styrene-maleic acid copolymer as thickener
50 ml of an aqueous solution and 30 g of a polymer latex of ethyl acrylate were added, and 1-hydroxy-3,5-
20 ml of a 1% aqueous solution of sodium dichlorotriazine and 10 ml of a 4% aqueous solution of formalin were added and stirred, and the mixture was applied to the surface of the film opposite to the surface coated with gelatin. Further, an aqueous solution containing gelatin and the following compound (A) was applied thereon as a protective layer.

[0071]

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[0072] The backing layer is a gelatin solution was added the following additives gelatin underlayer 2.3 g / m ^2, was coated so that the upper layer 1.0 g / m ^2.

[Backing layer]

[0074]

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[Backing Upper Layer] PMMA Average particle size 5 μm 30 mg / m ² Compound (A) 15 mg / m ² Styrene-maleic acid copolymer 20 mg / m ² Glyoxal 30 mg / m ^{2 Further} , the PET base is prepared in advance on the backing layer side. An antistatic polymer was used.

The thus prepared film samples 1 to
No. 21 performed the following processing.

Developer formulation (composition A) Pure water (ion-exchanged water) 150 ml Disodium ethylenediaminetetraacetate 2 g Diethylene glycol 50 g Potassium sulfite (55% w / v aqueous solution) 100 ml Potassium carbonate 50 g Hydroquinone 15 g 5-methylbenzotriazole 200 mg 1 -Phenyl-5-mercaptotetrazole 30mg Potassium bromide 4.5g Potassium hydroxide, the amount to make pH after use 10.4 (Composition B) Pure water (ion exchange water) 3ml Diethylene glycol 50g Ethylenediaminetetraacetic acid disodium salt 25mg Acetic acid (90 % Aqueous solution) 0.3 ml 5-nitroindall 110 mg 1-phenyl-3-pyrazolidone 700 mg When using a developing solution, the above-mentioned composition A and composition B were dissolved in 500 ml of water in this order, and finished to 1 liter.

Fixer formulation (composition A) Ammonium thiosulfate (72.5% w / v aqueous solution) 240 ml Sodium sulfite 17 g sodium acetate trihydrate 6.5 g boric acid 6 g sodium citrate dihydrate 2 g acetic acid (90% w / v aqueous solution) ) 13.6 ml (composition B) pure water (ion-exchanged water) 17 ml sulfuric acid (50% w / v aqueous solution) 4.7 g when using aluminum sulfate (Al ₂ O ₃ in terms of content of 8.1% w / v aqueous solution) 26.5 g fixer The composition A and the composition B were dissolved in 500 ml of water in this order, and used after finishing to 1 liter. The pH of this fixing solution was about 4.3.

The automatic developing machine used was GR-27 manufactured by Konica Corporation. The development temperature time was 28 ° C. and 30 ″. The residual color used was the value obtained by measuring the unexposed portion with X-Rite. The sensitivity was measured using Sample No. 1 as an optical densitometer (PDA-65 manufactured by Konica).
The density was measured, and the sensitivity at a density of 2.5 was expressed as a relative sensitivity, taking the sensitivity as 100.

The exposure was performed using a high-intensity sensitometer manufactured by Yamashita Denso Co., Ltd. at 10 ⁻⁵ sec using a 660 mm interference filter. At that time, exposure was performed through a wedge.

[0081]

[Table 1]

As is clear from Table 1, the present invention has high sensitivity and little residual color.

Example 2 The sample used in Example 1 was subjected to ultra-rapid processing. The developing solution and the fixing solution were the same as in Example 1, and the developing conditions were 38 ° C.
12 ", and the automatic developing machine used was GR-26SR manufactured by Konica Corporation.

[0084]

[Table 2]

As is evident from Table 2, the present invention has high sensitivity even at a very high speed and has little residual color.

[0086]

According to the present invention, it is possible to form a printing material having high sensitivity and little residual color while enduring ultra-rapid processing.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-242932 (JP, A) JP-A-56-144428 (JP, A) JP-A-2-143242 (JP, A) JP-A-3-243 171135 (JP, A) JP-A-3-203765 (JP, A) JP-A-3-156441 (JP, A) JP-A-50-87638 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G03C 1/38 G03C 1/12

Claims (1)

(57) [Claims] 1. A silver halide light-sensitive material having at least one silver halide emulsion layer, wherein at least one layer of the silver halide light-sensitive material has one of the following general formulas [1] to [5].
A silver halide light-sensitive material comprising at least one compound selected from compounds represented by the formula (I) and at least one compound represented by the following formula (6): Embedded image Embedded image In [formula (1), X is -S- or -Se-, at least two _{R 1, R 2, R 3} , R 4 and R ₅ represents an organic group having a water-soluble group. However, both R ₃ and R ₄ do not represent this. R ₁ , R ₂ , R ₃ , R ₄ and R ₅ which do not represent the organic group having a water-soluble group are hydrogen, an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl group, an aryl group or a substituted aryl group. Represents R ₆ or R ₇
Are the same or different, hydrogen, hydroxy group, halogen atom, alkyl group, substituted alkyl group, alkenyl group, substituted alkenyl group, alkynyl group, substituted alkynyl group, alkoxy group, substituted alkoxy group, alkylthio group, substituted alkylthio group, Arylthio group, substituted arylthio group, aryl group, substituted aryl group, acyl group, substituted acyl group, acyloxy group, substituted acyloxy group, alkoxycarbonyl group, substituted alkoxycarbonyl group, alkylsulfonyl group, substituted alkylsulfonyl group, carbamoyl group, substituted Represents a carbamoyl group, a sulfamoyl group, a substituted sulfamoyl group, a carboxy group or a cyano group, or R ₆ and R ₇ represent the atoms necessary to link to complete a carbocyclic ring system; _6, wherein the substitutions indicated for R ₇ The same or different one or more substituents selected from can be supported. In the general formula [2], Y represents, -S- or - Se - at and at least two _{Z 1, Z 2, Z 3} , Z 4, Z 5 and Z ₆ represents an organic group having a water-soluble group (However, Z ₄ and Z ₅ do not represent both.) Z _{1 to} Z ₆ which do not represent the organic group having a water-soluble group are hydrogen, an alkyl group, a substituted alkyl group, an alkenyl group, a substituted alkenyl. Group, aryl group,
Or, it represents a substituted aryl group, and Z ₇ and Z ₈ are the same or different and have the same meaning as R ₆ and R _{7 in} general formula [1]. In the general formula [3], Y ₁ and Y ₂ each represent a nonmetallic atomic group necessary for forming a benzothiazole ring, a benzoselenazole ring, a naphthothiazole ring, a naphthoselenazole ring, or a quinoline ring; These heterocycles may be substituted with a lower alkyl group, an alkoxy group, an aryl group, a hydroxyl group, an alkoxycarbonyl group, or a halogen atom. R ₁ and R ₂ each represent a lower alkyl group, an alkyl group having a sulfo group or an alkyl group having a carboxyl group. R ₃ represents a methyl group, an ethyl group, or a propyl group. X ₁ represents an anion. n ₁ , n
₂ represents 1 or 2. m represents 1 or 0, and in the case of an internal salt, m = 0. In the general formula [4], R and R ₁ are each an alkyl group,
It represents a substituted alkyl group, an aryl group, a substituted aryl group, or an allyl group, and at least one of R and R ₁ represents an alkyl group containing a sulfo group or an alkyl group containing a carboxyl group. R ₂ and R ₃ each represent an alkyl group. Z represents a nonmetallic atomic group necessary for completing a 5- or 6-membered nitrogen-containing heterocyclic nucleus. In the general formula [5], Y is S or Se.
L ¹ , L ² , L ³ , L ⁴ and L ⁵ are methine groups, which may be substituted with a substituent. A is NR ³ , O or S
When A is 0, B is NR ⁴ , and when A is NR ³ , B is NR ⁴ , S or O. R ¹ , R ² , R ³ ,
R ⁴ is a substituted or unsubstituted alkyl group or a substituted or unsubstituted aryl group. R ⁵ represents an alkyl group having 1 to 4 carbon atoms, and n is an integer of 0, 1 or 2. X is a counter ion. At least two of R ¹ , R ² , R ³ and R ⁴ are substituted with an acid or an acid base. In the general formula [6], R represents a hydrogen atom, an alkyl group, or an aryl group. n represents an integer of 1 to 10. ]