JPH0895187A - Spectral sensitizing dye for photography - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a spectral sensitizing dye for photographic use, which has little residual color due to dye contamination, high sensitivity, and less fog. [Structure] A sensitizing dye for photography, characterized by being represented by Chemical Formulas 1 and 2. [Chemical 1] [Chemical 2] [Wherein D ¹ and D ² represent a dye skeleton capable of spectrally sensitizing silver halide in the red to infrared region. R ^{1 to} R ⁴ represent a substituted or unsubstituted alkyl group or alkenyl group.
L ¹ represents a divalent linking group. R ⁵ represents a hydrogen atom or an alkyl group. Y represents N-R ^6, or S,. R ⁶ represents a substituted or unsubstituted alkyl group or alkenyl group. X
^- represents a counter anion. n represents an integer necessary to neutralize the charge. ]

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a spectral sensitizing dye for photography, and more particularly to a dye useful as a sensitizing dye used in a silver halide photographic light-sensitive material.

[0002]

2. Description of the Related Art A silver halide photographic light-sensitive material is required to have high sensitivity in different specific wavelength regions depending on its intended use. As one of the manufacturing techniques for such a silver halide photographic light-sensitive material, various types of cyanine dyes and merocyanine dyes are added to a silver halide photographic emulsion, and a wavelength longer than the intrinsic light-sensitive wavelength range of the silver halide is used. It is generally well known that, in the range, the sensitivity in a specific wavelength range is extremely effectively increased.

When spectral sensitization is applied to a silver halide photographic emulsion with a dye, it must satisfy not only the spectral sensitizing effect and the increase in sensitivity but also the following requirements. . (1) The spectral sensitization range is appropriate. (2) Stable photographic characteristics are maintained during storage of the light-sensitive material. (3) No stain or fog caused by the residual dye administered for spectral sensitization after development. (4) No bad interaction with other photographic additives. However, quite a lot of cyanine and merocyanine dyes are known to date, but among the sensitizing dyes having a spectral sensitization region in the red to infrared region, those satisfying the above various requirements such as sensitizing property and photographic characteristics are The reality is that there are few.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide an excellent spectral sensitizing dye for photographic use which satisfies the above-mentioned various requirements.

[0005]

As a result of various investigations, the present inventors have found that the sensitizing dyes represented by Chemical Formulas 1 and 2 are excellent dyes satisfying the above object. Further, those having the structures shown in Chemical formulas 3 and 4 as the dye skeleton are more preferable.

In the formula, D ¹ and D ² are in the red to infrared region (60
(0 to 850 nm) represents a dye skeleton capable of spectrally sensitizing silver halide. As a preferable dye skeleton,
There is a structure shown in Chemical formula 4. R ^{1 to} R ⁴ are substituted or unsubstituted alkyl groups (eg, methyl, ethyl, n
-Propyl, i-propyl, n-butyl, n-amyl group, β-hydroxyethyl, γ-hydroxypropyl,
β-acetoxyethyl, γ-acetoxypropyl, β-
Methoxyethyl, γ-methoxypropyl, carboxymethyl, β-carboxyethyl, γ-carboxypropyl, δ-carboxybutyl, ω-carboxypentyl,
Methoxycarbonylmethyl, ethoxycarbonylmethyl, β-methoxycarbonylethyl, γ-methoxycarbonylpropyl, δ-methoxycarbonylbutyl, β-
Sulfoethyl, γ-sulfopropyl, γ-sulfobutyl, δ-sulfobutyl, benzyl, phenethyl, p-carboxybenzyl, p-sulfophenethyl, etc.) and alkenyl groups (eg, allyl). L ¹ represents a divalent linking group (eg, alkylene, arylene group, etc.). R ⁵ represents a hydrogen atom or an alkyl group (eg, methyl, ethyl, n-propyl group, etc.). Y represents N-R ^6, or S,. R ⁶ is a substituted or unsubstituted alkyl group (synonymous with R ^{1 to} R ⁴ ), alkenyl group (R ^{1 to} R 4
Synonymous with the case of ⁴ ). X ⁻ represents a counter anion (for example, chlorine, bromine, iodine, perchloric acid, benzenesulfonic acid, p-toluenesulfonic acid, methylsulfate, ethylsulfate ion, etc.). n represents an integer necessary to neutralize the charge.

Next, chemical formulas 3 and 4 will be described. Z in the formula
^{1 to} Z ⁶ each represent an atomic group necessary for forming a 5- or 6-membered nitrogen-containing heterocycle. Specific examples of Z ^{1 to} Z ³ and Z ⁶ (indicated by the name of the starting material tertiary base for convenience) include, for example, an oxazoline ring, an oxazole ring, a benzoxazole ring, a naphthoxazole ring, a thiazoline ring,
Thiazole ring, thiazine ring, benzothiazole ring, naphthothiazole ring, benzoselenazole ring, naphthoselenazole ring, quinoline ring, benzoquinoline ring, indolenine ring, benzoindolenine ring, benzimidazole ring,
There are naphthoimidazole rings and the like. Further, carbon atoms of these heterocycles include a halogen atom (for example, chlorine and bromine atom), an alkyl group (for example, methyl, ethyl, n-propyl, n-butyl, t-butyl, n-amyl group) and alkoxy. Groups (eg methoxy, ethoxy, n
-Propoxy group), hydroxy group, trifluoromethyl group, cyano group, alkanesulfonyl group (eg, methanesulfonyl, ethanesulfonyl group, etc.), sulfamoyl group (eg, sulfamoyl, N, N-dimethylsulfamoyl, piperidyl) And a substituent such as an aryl group (eg, phenyl, methoxyphenyl group, etc.) may be attached. Specific examples of the nitrogen-containing heterocyclic ring formed by Z ⁴ and Z ⁵ include, for example, a thiazolidine ring and an imidazolidine ring, and examples of the nitrogen substituent of these heterocyclic rings include alkyl groups (R ^{1 to} R ^{1 4} ), an alkenyl group (synonymous with R ^{1 to} R ⁴ ) and an aryl group (eg,
Phenyl, methoxyphenyl group, etc.) and the like. R ⁷ ~
R ¹⁰ is a substituted or unsubstituted alkyl group (if synonymous with R ¹ ~R ^4), an alkenyl group (if synonymous with R ¹ ~R ^4). L ^{2 to} L ⁵ each represent a substituted or unsubstituted methine group unit of 1 to 7 units. Examples of the substituents are an alkyl group (synonymous with R ^{1 to} R ⁴ ), an aryl group (eg, phenyl, methoxyphenyl group, etc.), an alkoxy group (eg, methoxy, ethoxy, n-propoxy group, etc.) There is. They may also be bridged together to form a 5 or 6 membered substituted or unsubstituted carbocyclic ring. X ⁻ represents a counter anion (synonymous with the case of Chemical formula 1 and Chemical formula 2). m represents 0 or 1. n represents an integer necessary to neutralize the charge.

Specific examples of the sensitizing dye used in the present invention are shown below. However, the sensitizing dye used in the present invention is not limited to these.

[0009]

[Chemical 5]

[0010]

[Chemical 6]

[0011]

[Chemical 7]

[0012]

[Chemical 8]

[0013]

[Chemical 9]

[0014]

[Chemical 10]

[0015]

[Chemical 11]

[0016]

[Chemical 12]

[0017]

[Chemical 13]

[0018]

[Chemical 14]

[0019]

[Chemical 15]

[0020]

[Chemical 16]

[0021]

[Chemical 17]

[0022]

[Chemical 18]

[0023]

[Chemical 19]

[0024]

Embedded image

[0025]

[Chemical 21]

[0026]

[Chemical formula 22]

[0027]

[Chemical formula 23]

[0028]

[Chemical formula 24]

[0029]

[Chemical 25]

[0030]

[Chemical formula 26]

[0031]

[Chemical 27]

Next, among the dyes of the present invention, typical synthesis examples will be described.

Synthesis of Chemical Formula 5

13.0 g of 6-amino-2-methylmercaptobenzothiazole was mixed with 400 ml of 2N hydrochloric acid, and 7.6 g of thiophosgene was added with stirring at room temperature. After stirring at the same temperature for 7 hours, the precipitated crystals were collected by filtration, washed with water and ethanol in this order and then dried to obtain 12.2 g of isothiocyanate derivative: intermediate A. (Melting point 89-94 ° C)

2.4 g of intermediate A and 25 m of acetonitrile
1, and mixed with N-methylpiperazine under stirring at room temperature.2.
0 g was added. Then, the temperature was raised and the mixture was heated under reflux for 20 minutes. After cooling, the precipitated crystals were collected by filtration, washed with acetonitrile, water and ethanol in this order and dried to obtain 2.2 g of thiourea derivative: intermediate B. (Melting point 172-1
74.5 ° C)

Intermediate B 0.85 g and dimethyl sulfate 1.6
0 g was mixed and heated at a bath temperature of 100 ° C. for 30 minutes. Then 3-ethyl-6-methoxy-2- (3,5,5-trimethyl-2-cyclohexene-1-ylidene) methylbenzoxazolium iodide 1.10 g, DMF10
ml was added, and the mixture was heated again at a bath temperature of 100 ° C. to make the mixture uniform, and then 2.0 ml of triethylamine was added. After reacting for 5 minutes, 100 ml of isopropyl ether was added, the mixture was cooled, stirred well, and the supernatant was removed by decantation. To the residue, 80 ml of ethanol and an aqueous solution of sodium perchlorate (1.0 g / 10 ml) were added, and the mixture was cooled to 3 with ice water.
After stirring for 0 minutes, the insoluble matter was filtered off and washed with ethanol, water and ethanol in this order. The crude pigment powder thus obtained was recrystallized from methanol to obtain 0.18 g of Chemical formula 5. (Melting point 200 ° C- (decomposition), absorption maximum of methanol solution 639 nm)

Synthesis of Formula 25

2.4 g of intermediate A and 25 m of acetonitrile
1, and thiomorpholine (2.1 g) was added with stirring at room temperature. Then, the temperature was raised and the mixture was heated under reflux for 20 minutes. After allowing to cool, the precipitated crystals are filtered off, acetonitrile,
It was washed with water and ethanol in this order and then dried to obtain 2.6 g of thiourea derivative: intermediate C. (Melting point 194.5-19
6 ° C)

3-ethyl-5- [3- (3-ethyl-α
-Naphthiazolin-2-ylidene) methyl-5,5-
Dimethyl-2-cyclohexene-1-ylidene] rhodanine 0.73 g, intermediate C 0.46 g, dimethyl sulfate 1.90 g, and m-cresol 2 ml were mixed, and the bath temperature 10
Heat at 0 ° C. for 15 minutes. Then, 30 ml of ethanol was added, and 1.6 ml of triethylamine was added with heating under reflux. After reacting for 30 minutes, the crystals precipitated during heating were filtered.
The crude pigment powder thus obtained was recrystallized from methanol to obtain 0.30 g of Compound 25. (Melting point 214 ° C
~ (Decomposition), absorption maximum of methanol solution 707 nm)

The silver halide photographic emulsion in which the sensitizing dye used in the present invention is used is a silver chloride, silver bromide, silver chlorobromide, silver iodobromide, silver chloroiodobromide prepared by a conventional method. Etc. may be used.

To add the sensitizing dye of the present invention to these silver halide photographic emulsions, an organic solvent such as methanol, ethanol, acetone, cellosolve, pyridine or dimethylformamide, which is optionally miscible with an aqueous solution or water, is used alone. Alternatively, it can be added as a solution of a mixed solvent. Also,
It is generally preferable to add these sensitizing dyes to the silver halide photographic emulsion immediately after the completion of the second ripening. The addition amount varies depending on the type of sensitizing dye or the type of silver halide photographic emulsion, but it can be used in a wide range of about 4 to 1,200 mg per 100 g in terms of silver nitrate.

The silver halide photographic emulsion in which the sensitizing dye of the present invention is used is subjected to noble metal sensitization, sulfur sensitization, reduction sensitization and sensitization combining them, or addition of a polyalkylene oxide compound or the like. May be.

The silver halide photographic emulsion in which the sensitizing dye of the present invention is used may be spectrally sensitized with other sensitizing dyes, for example, known cyanine and merocyanine dyes, if necessary. Stabilizer, surfactant,
Hardener, optical brightener, UV absorber, filter dye,
Additives such as anti-irradiation dyes, anti-halation dyes, preservatives, plasticizers, matting agents, color couplers and the like can be contained. Further, when used in a light-sensitive material for stabilizing processing, a developing agent or its precursor can be contained.

As protective colloids for silver halide photographic emulsions in which the sensitizing dye of the present invention is used, besides gelatin, gelatin derivatives such as phthalated gelatin and malonated gelatin, cellulose derivatives, soluble starch, water-soluble polymers, etc. Is mentioned.

The support to which the silver halide photographic emulsion containing the sensitizing dye of the present invention is applied is, for example, baryta paper, plastic-laminated paper, synthetic paper, resin film such as cellulose triacetate or polyethylene terephthalate. Can be used. If necessary, an undercoat layer and an antihalation layer may be provided on these supports by a known method.

[0046]

EXAMPLES The present invention will now be described in detail with reference to examples, but the present invention is not limited thereto.

Example 1 A silver chloride emulsion prepared by a conventional method for producing a silver halide photographic emulsion was sensitized with a sensitizing dye of the present invention and a sensitizing dye for comparison 2.
1.2 ml of 0.05% DMF solution of 8
/ GAg was added. 45 these emulsions in a 40 ° C bath
The spectral sensitization effect was stabilized after a lapse of minutes. Then, after adding a predetermined amount of a stabilizer, a surfactant and a hardener, it was coated on a polyethylene-laminated paper support, dried, and left at 35 ° C. overnight. Then, it was cut into an appropriate size and used as a test sample. Each sample thus obtained was wedge-exposed according to the ISO method, and a D-72 developing solution (developing solution of Eastman Kodak Co., USA) was used.
It was developed at 0 ° C. for 90 seconds, stopped and fixed, further washed with water, and dried to obtain strips having a predetermined black and white image. This is a MAC manufactured by Macbeth Corporation of the United States
The density was measured using an HBETH-TD504 densitometer, and the sensitivity, fog and residual color were evaluated. The reference point of the optical density for which the sensitivity was determined was the point of [fog + 0.70]. The white light sensitivity was set to 100 for the non-added sample to which no sensitizing dye was administered, and the red sensitivity was the Ratten Gelatin Filter No. manufactured by Eastman Kodak Company. 29, and the relative value when the sensitivity value of Comparative Sensitizing Dye 30 is set to 100. The residual color was evaluated by visually evaluating the hue of the unexposed area. "5" represents the best quality and "1" represents the worst quality. The results are shown in Table 1.

[0048]

[Chemical 28]

[0049]

[Chemical 29]

[0050]

[Chemical 30]

[0051]

[Table 1]

As is clear from Table 1, the sensitizing dyes of the present invention have less residual color after processing than the sensitizing dyes for comparison and show superiority in sensitivity and fog.

Example 2 A sample was prepared in the same manner as in Example 1 except that the following chemical compounds 31, 32 and 33 were used as comparative sensitizing dyes. The sensitivity is a relative value when the sensitivity value of Comparative Sensitizing Dye 33 is 100. The results are shown in Table 2.

[0054]

[Chemical 31]

[0055]

[Chemical 32]

[0056]

[Chemical 33]

[0057]

[Table 2]

As is clear from Table 2, the sensitizing dye of the present invention has less residual color after processing and is superior in sensitivity and fog as compared with the comparative sensitizing dye.

[0059]

By using the sensitizing dye of the present invention,
It is possible to obtain a silver halide photographic light-sensitive material which has little residual color due to dye contamination, high sensitivity, and less fog.

Claims (2)

[Claims] 1. A spectral sensitizing dye for photography represented by the following chemical formulas 1 and 2. [Chemical 1] [Chemical 2] [Wherein D ¹ and D ² represent a dye skeleton capable of spectrally sensitizing silver halide in the red to infrared region. R ^{1 to} R ⁴ represent a substituted or unsubstituted alkyl group or alkenyl group.
L ¹ represents a divalent linking group. R ⁵ represents a hydrogen atom or an alkyl group. Y represents N-R ^6, or S,. R ⁶ represents a substituted or unsubstituted alkyl group or alkenyl group. X
^- represents a counter anion. n represents an integer necessary to neutralize the charge. ] 2. The spectral sensitizing dye for photography according to claim ¹ , wherein D ¹ and D ² are represented by the following chemical formulas 3 and 4. [Chemical 3] [Chemical 4] [In the formula, Z ^{1 to} Z ⁶ each represent an atomic group necessary for forming a 5- or 6-membered nitrogen-containing heterocycle. R ^{7 to} R ¹⁰ represent a substituted or unsubstituted alkyl group or alkenyl group.
L ^{2 to} L ⁵ each represent a substituted or unsubstituted methine group unit of 1 to 7 units. X ⁻ represents a counter anion. m represents 0 or 1. n represents an integer necessary to neutralize the charge. ]