JPH06222492A - Photographic special sensitizing dye - Google Patents

Abstract

PURPOSE:To provide photographic spectral sensitizing dye high in sensitivity and small in residual color due to dye stains and fogging. CONSTITUTION:The photographic spectral sensitizing dye is characterized by being represented by the formula in which each of Z<1> and Z<2> is an atomic group necessary to form a benzoxazole, bezothiazole, benzoselenazole, or benzimidazole ring; each of R<1> and R<2> is, independently, optionally substituted alkyl or alkenyl; each of R<3>-R<6> is, independently, an optionally substituted alkyl or alkenyl or aryl; each of L1-L7 is, independently, an optionally substituted methine; each of m and n is, independently, 0 or 1, but not 0 at the time; and X is a counter ion.

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 unique light-sensitive wavelength region 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.

In the case of applying spectral sensitization to a silver halide photographic emulsion with a dye, it is necessary not only to impart a spectral sensitizing effect and increase sensitivity but also to satisfy 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, although quite a large number of cyanine and merocyanine dyes are known to date, tricarbocyanines that impart photosensitivity to the red region and the near infrared region (for example, US Pat. Nos. 3,482,978 and 3,552). , 974
No. 3,573,921, No. 4,536,47
As described in No. 3, etc.), there are few that satisfy the above various requirements such as sensitization and photographic characteristics.

[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 dye represented by Chemical formula 1 is an excellent dye satisfying the above object.

In the formula, Z ¹ and Z ² represent an atomic group necessary for forming a benzoxazole ring, a benzothiazole ring, a benzoselenazole ring or a benzimidazole ring, and a benzene ring is condensed with these heterocycles. Further, the carbon atom of these heterocycles may have a halogen atom (eg, chlorine, bromine atom, etc.), an alkyl group (eg, methyl, ethyl, n-propyl, n-butyl, t-).
Butyl, n-amyl group, etc.), alkoxy group (eg,
Methoxy, ethoxy, n-propoxy group, etc.), hydroxy group, trifluoromethyl group, cyano group, alkanesulfonyl group (eg, methanesulfonyl, ethanesulfonyl group, etc.), sulfamoyl group (eg, sulfamoyl, N, N-dimethylsulfur) Substituents such as famoyl, piperidinosulfonyl, morpholinosulfonyl group) and aryl groups (eg, phenyl, methoxyphenyl group, etc.) may be attached. R ¹ and R ² are each independently a substituted or unsubstituted alkyl group (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, ethoxycarbonyl Methyl, β-methoxycarbonylethyl, γ-
Methoxycarbonylpropyl, δ-methoxycarbonylbutyl, β-sulfoethyl, γ-sulfopropyl, γ-
Sulfobutyl, δ-sulfobutyl, benzyl, phenethyl, p-carboxybenzyl, p-sulfophenethyl group and the like) and alkenyl group (eg, allyl). R
³ , R ⁴ , R ⁵ and R ⁶ are each independently a substituted or unsubstituted alkyl group (synonymous with R ¹ and R ² ), alkenyl group (synonymous with R ¹ and R ² ), aryl A group (for example, a phenyl group, a tolyl group, a methoxyphenyl group, etc.) is shown, and among them, an alkyl group having 6 or less carbon atoms is preferable. L ¹ , L ² , L ³ , L ⁴ , L ⁵ , L ⁶ , and L ⁷ are
Each independently represents a substituted or unsubstituted methine group, which may be bridged with each other to form a 5- or 6-membered substituted or unsubstituted carbocyclic ring. m and n each independently represent an integer of 0 or 1, but they never become 0 at the same time. X is a counter ion necessary for balancing the charge of the dye molecule (eg, chlorine, bromine, iodine, perchloric acid, benzenesulfonic acid, p-toluenesulfonic acid, methylsulfate, ethylsulfate, potassium, sodium,
Pyridinium, triethylammonium ion, etc.), which forms an inner salt when it is part of the dye molecule itself.

Specific examples of the sensitizing dye represented by Chemical Formula 1 used in the present invention are shown below. However, the sensitizing dye used in the present invention is not limited to these.

[0008]

[Chemical 2]

[0009]

[Chemical 3]

[0010]

[Chemical 4]

[0011]

[Chemical 5]

[0012]

[Chemical 6]

[0013]

[Chemical 7]

[0014]

[Chemical 8]

[0015]

[Chemical 9]

[0016]

[Chemical 10]

[0017]

[Chemical 11]

[0018]

[Chemical 12]

[0019]

[Chemical 13]

[0020]

[Chemical 14]

[0021]

[Chemical 15]

Next, among the dyes represented by Chemical Formula 1 of the present invention,
A typical synthesis example will be described.

Synthesis of Chemical Formula 2

2-Methyl-6-methylsulfonamidobenzoxazole (6.0 g) and ethyl-p-toluenesulfonate (5.3 g) were mixed and heated at a bath temperature of 130 ° C. for 4 hours. After allowing to cool, 15 ml of acetone was added, and the mixture was stirred at room temperature for 1 hour. Then, the precipitated crystals were collected by filtration, washed with acetone and dried to obtain 3-ethyl-2-methyl-6-methylsulfonamide benzoxazolium-p-toluenesulfonate: intermediate A (8.5 g).

Intermediate A 3.0 g, ethyl-N-phenylformimidate 1.6 g, methyl cellosolve 10 ml
And were mixed and heated and stirred at a bath temperature of 100 ° C. for 30 minutes. After allowing to cool, 5 ml of water was added, and the mixture was heated to homogeneity, and then 2 g of sodium iodide was added. After cooling, the precipitated crystals were collected by filtration, washed with water, dioxane and diethyl ether in this order and dried to give 2- (2-anilinovinyl) -3-ethyl-6.
-Methylsulfonamide benzoxazolium iodide: 1.3 g of intermediate B were obtained. (Melting point 268 ° C-decomposition)

Intermediate B 0.30 g, 3-ethyl-2-
(3,5,5-trimethyl-2-cyclohexene-1-
Ylidene) methylbenzothiazolium iodide 0.26
g, 1.0 m of acetic anhydride and 4 ml of pyridine were mixed, and 0.4 ml of triethylamine was added while stirring at a bath temperature of 90 to 100 ° C., and stirring was continued at the same temperature for 3 minutes. After cooling, 50 ml of isopropyl ether was added and stirred well, and then the supernatant was removed by decantation. 0.5 g of sodium perchlorate and 10 ml of methanol were added to the residue, and the mixture was heated under reflux for 5 minutes. After cooling, the precipitated crystals are filtered, washed with methanol and dried to give a melting point of 249 ° C.
0.10 g of (decomposed) green-blue crystalline powder was obtained. The absorption maximum of the methanol solution was 725 nm.

The silver halide photographic emulsion in which the sensitizing dye represented by Chemical Formula 1 used in the present invention is used is a silver chloride, silver bromide, silver chlorobromide, silver iodobromide prepared by a conventional method. , Silver chloroiodobromide or the like.

To add the sensitizing dye represented by Chemical Formula 1 of the present invention to these silver halide photographic emulsions, methanol, ethanol, acetone, cellosolve, pyridine and dimethylformamide, which are optionally miscible with an aqueous solution or water. Can be added alone or as a solution of a mixed solvent. Further, it is generally preferable to add these sensitizing dyes to the silver halide photographic emulsion immediately after the completion of the second ripening. The amount added varies depending on the type of sensitizing dye or the type of silver halide photographic emulsion,
Approximately 4 to 1,200 per 100g converted to silver nitrate
It can be used in a wide range of mg.

The silver halide photographic emulsion in which the sensitizing dye represented by Chemical Formula 1 of the present invention is used includes noble metal sensitization, sulfur sensitization, reduction sensitization and sensitization combining them or polyalkylene oxide compounds. It may be added.

The silver halide photographic emulsion in which the sensitizing dye represented by Chemical Formula 1 of the present invention is used may be spectrally sensitized with other sensitizing dyes, for example, known cyanine and merocyanine dyes, if necessary. Well, further by known methods stabilizers, surfactants, hardeners, optical brighteners, ultraviolet absorbers,
Additives such as filter dyes, 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 a protective colloid for a silver halide photographic emulsion in which the sensitizing dye represented by the chemical formula 1 of the present invention is used, gelatin derivatives such as phthalated gelatin and malonated gelatin, cellulose derivatives, and soluble starch can be used in addition to gelatin. , Water-soluble polymers and the like.

Examples of the support coated with the silver halide photographic emulsion containing the sensitizing dye represented by Chemical Formula 1 of the present invention include baryta paper, plastic-laminated paper, synthetic paper, cellulose triacetate and polyethylene terephthalate. Resin films and the like can be used. If necessary, an undercoat layer and an antihalation layer may be provided on these supports by a known method.

[0033]

EXAMPLES The present invention will be specifically described below with reference to examples.

To a silver chloride emulsion prepared by a conventional method for producing a silver halide photographic emulsion, 3.0 ml of 0.05% methanol solution of the sensitizing dyes 16 and 17 for comparison with the sensitizing dye of the present invention / GAg was added. 40 of these emulsions
The spectral sensitizing effect was stabilized by aging for 45 minutes in a bath at ° C. 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. A part of this sample (fresh) was aged for 3 days under the conditions of 50 ° C. and 80% relative humidity to prepare a sample (thermo).

[0035]

[Chemical 16]

[0036]

[Chemical 17]

Then, it was cut into an appropriate size to prepare a test sample. Each sample thus obtained was wedge-exposed according to the ISO method, developed with D-72 developer (developer formulation of Eastman Kodak Co., USA) at 20 ° C. for 90 seconds, stopped, and fixed. After washing with water and drying, strips having a predetermined black and white image were obtained. This is MACHBETH-TD manufactured by Macbeth Corporation of the United States.
The density was measured using a 504 densitometer to evaluate sensitivity, fog and residual color, and the results are shown in Table 1. The reference point of the optical density for which the sensitivity was determined was the point of [fog + 0.70]. Further, the sensitivity was shown as a relative value when the sensitivity value of a fresh sample of Comparative Sensitizing Dye 16 was 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.

[0038]

[Table 1]

As is clear from Table 1, the sensitizing dyes of the present invention are superior to the comparative sensitizing dyes in terms of sensitivity, fog and residual color. Furthermore, 5
It can be seen that the sample that has been aged for 3 days under the conditions of 0 ° C. and 80% relative humidity is also excellent with little change in sensitivity and fog.

[0040]

By using the sensitizing dye 1 of the present invention, it is possible to obtain a silver halide photographic light-sensitive material having high sensitivity and less residual color or fog due to dye contamination.

Claims (1)

[Claims] 1. A spectral sensitizing dye for photography represented by the following chemical formula 1. [Chemical 1] [Wherein Z ¹ and Z ² represent an atomic group necessary for forming a benzoxazole ring, a benzothiazole ring, a benzoselenazole ring or a benzimidazole ring. R ¹ and R ²
Each independently represent a substituted or unsubstituted alkyl group or alkenyl group, and R ³ , R ⁴ , R ⁵ and R ⁶ are
Each independently represents a substituted or unsubstituted alkyl group, alkenyl group, or aryl group. L ¹ , L ² , L ³ , L
⁴ , L ⁵ , L ⁶ and L ⁷ each independently represent a substituted or unsubstituted methine group. m and n are 0 independently
Or, it represents an integer of 1, but never 0 at the same time. X represents a counter ion. ]