JPH048466B2 - - Google Patents

Description

[Detailed description of the invention]

(A) Industrial Application Field The present invention relates to a photographic light-absorbing dye, and more particularly to a dye useful as a light-absorbing dye for use in silver halide photographic light-sensitive materials. (B) Prior art Silver halide photographic materials absorb harmful reflections, scattering, and diffused light in their light-sensitive emulsion layers, or absorb harmful light from the interface between the emulsion layer and the support base and from the back surface of the support. It is well known to prevent irradiation and halation and improve the sharpness of finished photographic images by absorbing undesired reflected light from the photographic image. In addition, when there are multiple photographic emulsion layers such as in a multilayer color photographic light-sensitive material, a colored layer (filter layer) is provided above the emulsion layer or between them to control the spectral composition that should be incident on the photographic emulsion layer. Control is also well known. In order to prevent irradiation and halation, dyes applied to the light-sensitive emulsion layer, between the emulsion layer and the support, to the backing layer of the support, or into the filter layer should be used during solution preparation or during the production of the light-sensitive emulsion. It goes without saying that changes over time such as discoloration and fading must not occur during storage and storage, but photographic properties such as fogging and desensitization must not be adversely affected. Furthermore, during the development process, it must be completely and quickly decolored or must be eluted and removed from the photographic material. Preferably, the dye is of a decoloring type, and the decolorized dye is eluting and does not become colored by the treatment liquid. Furthermore, it must have spectral absorption characteristics that meet the respective purposes, and must have the effects of preventing irradiation, preventing halation, and acting as a spectral filter. However, although quite a large number of dyes have been proposed to date, they have poor decolorizing properties, dissolution properties, photographic properties, etc.
The reality is that there are only a few that satisfy the above conditions. (C) Object of the Invention Accordingly, the object of the present invention is to provide a photographic light-absorbing dye that satisfies the above conditions and has excellent radiation, halation and filter effects. (D) Structure of the Invention As a result of various studies, the present inventors have discovered that the dye represented by the following general formula is an excellent dye that satisfies the above object. general formula In the above general formula, R ₁ and R ₂ may be the same or different and each is a lower alkyl group (for example,
methyl, ethyl, propyl, butyl, amyl, etc.)
, L is a lower alkyl group (for example, the above R ₁ , R ₂
) represents an optionally substituted methine group, and l represents an integer 1 or 2. The dye represented by the above general formula is an alkali metal salt (for example,
It can take the form of potassium, sodium, etc.) and ammonium salts (triethylammonium, pyridinium, etc.). Although the silver halide photographic material colored with the dye of the present invention represented by the above general formula has a wide absorption band in the target wavelength range, it is almost unnecessary in other wavelength ranges. In addition, the dyes of the present invention all have high molecular extinction coefficients, and can be used in small amounts without causing any negative effects on photographic properties such as fog or desensitization, and can provide excellent irradiation prevention and Halation prevention and filter effects can be fully exhibited. In addition, after the development process, the dye is completely and quickly decolorized and eluted from the photosensitive material.
In the finished photographic image, not only does the dye contained for the above purpose remain, but also color contamination due to recoloring of the decolorizing dye, and further dyeing due to coloring of the processing solution are not observed. Furthermore, the dye of the present invention does not undergo any changes such as discoloration or fading during the preparation of the dye solution, and is stable without being affected by external conditions such as moist heat during the production of the photosensitive emulsion or during subsequent storage. It has the advantage of being Next, typical examples of the dyes represented by the above general formula of the present invention will be listed. Next, typical examples of dye synthesis methods will be specifically described. Synthesis of dye 3: 17.0 g of 3-ethoxycarbonyl-1-methyl-5-pyrazolone and 12.9 g of β-anilinoacroleinyl hydrochloride were dissolved in 100 ml of ethanol under heating.
Add 15.1 g of triethylamine to this and heat under reflux for 30 minutes. After cooling to room temperature, the precipitated crude dye is collected by filtration. After washing with ethanol, recrystallize with isopropanol and dry. 6.2 g of the triethylammonium salt of Dye 3 with a melting point of 162.0-162.5 DEG C. is obtained as a golden crystalline powder. Maximum absorption value of aqueous solution is 551 nm. Synthesis of dye 6: 17.0 g of 3-ethoxycarbonyl-1-methyl-5-pyrazolone and pentadienedianyl hydrochloride
Dissolve 14.2 g in 100 ml of ethanol, add 15.1 g of triethylamine, and stir at room temperature for 1 hour.
Next, the solvent is distilled off under reduced pressure on a water bath, 100 ml of saturated brine is added to the residue, and the precipitated crude dye is collected by filtration.
Wash with 10% saline. Next, the mixture is washed with a mixed solvent of methanol/ethanol and dried to obtain 17.9 g of the sodium salt of Dye 6 with a melting point of 300° C. or higher as a light blue crystal powder.
Maximum absorption value of aqueous solution is 639 nm. Other dyes of the present invention represented by the general formula can be easily synthesized according to the above synthesis example. In order to add the dye of the present invention represented by the above general formula into a silver halide photographic emulsion or a protective colloid solution, an aqueous solution or a solution of methanol, ethanol, cellosolves, glycols, dimethylformamide, dimethylsulfoxide, pyridine, etc. It can also be added as a mixed solution of these organic solvents and water to an emulsion layer, backing layer, subbing layer, intermediate layer, protective layer, or ultraviolet absorbing layer. The amount of these dyes used varies depending on the photographic layer to which they are applied, but generally 5 to 5 to 1 ^m2 of area of the light-sensitive material.
It is applied at a concentration of 1000mg. Silver halide photographic emulsions in which the dyes of the present invention are used include, for example, silver chloride, silver bromide, chlorobromide salts,
There are emulsions such as silver iodobromide and silver chloroiodobromide. Further, the silver halide photographic emulsion in which the dye of the present invention is used is spectrally sensitized with a commonly used cyanine or merocyanine dye. Further, by a known method, basic mordants such as polymers containing amino groups or ammonium groups, polymers containing nitrogen-containing heterocycles, stabilizers and their precursors, surfactants, hardeners, ultraviolet absorbers, fluorescent Additives such as brighteners, developing agents and their precursors can be included. When a silver halide photographic emulsion is used in a color light-sensitive material, it can also contain a color coupler or a dispersant thereof. In addition to gelatin, protective colloids for silver halide emulsions include gelatin derivatives such as phthalated gelatin and malonated gelatin, water-soluble polymers such as polyvinyl alcohol and polyvinylpyrrolidone, and plasticizers and latte for dimensional stability. Tsukusu polymer etc. can be added. Furthermore, the silver halide photographic emulsion in which the dye of the present invention is used can be coated on a support such as baryta paper, resin-coated paper, synthetic paper, natural or synthetic polymer film such as cellulose triacetate-based or polyester-based polymer film. . Next, the present invention will be described in more detail with reference to Examples. Example 1 1.55 g of gelatin was added to 15.0 ml of water to swell it, and then heated to 40.0°C to dissolve the gelatin. To this gelatin solution were added an aqueous solution (2.0 x 10 ^-4 mol/2.0 ml of water) of the dye of the present invention and a comparative dye described below, a hardener, and a surfactant, and then water was added to bring the total volume to 20.0 ml. Next, this coloring solution was applied onto a polyester film base that had been undercoated to a coating amount of 85 g/m ² and heated at 50.0°C for 24 hours.
A sample was cut into a rectangle of 11.5 cm ² . The sample was immersed in D-72 developer at 30.0°C for 5 seconds and 15 seconds, then washed under running water for 10 seconds, and the adhering water droplets were sucked up with filter paper and dried to obtain a treated sample. The samples and treated samples were measured at 5 points using a Macbeth transmission densitometer TD-504, and the average value was taken as the concentration of each. The results obtained are shown in Table-1.

[Table] *Represents base concentration.
As is clear from Table 1, the dye of the present invention not only has a high initial density, but also a large difference in density after treatment. That is, it can be seen that the dye has excellent decolorization and dissolution properties. Example 2 When a 1% aqueous solution of dye is added to a 10% aqueous gelatin solution to form a coating layer of 85 g/m ² , the optical density is 1.0.
Add 5 ml of 10% saponin solution to 150 ml of gelatin solution and 10% formalin.
Using the colored aqueous gelatin solution obtained by adding 1.5 ml, a hardened coating layer having an optical density of 1.0 is obtained by the same operation as in Example 1. A pure silver bromide emulsion was coated on top of this coated layer, and a developer with the following composition was used.
After developing at 20° C. for 1 minute and 30 seconds, it was fixed, washed with water, and dried according to a conventional method. When the optical density of the obtained treated film was measured using the method carried out in Example 1, the density after treatment of each stock containing the dye of the present invention was all 0.02. (However, the base concentration is 0.02) Composition of developer Metol 3g Sodium sulfite 45g Hydroquinone 12g Sodium carbonate (monohydrate) 80g Potassium bromide 2g Add water to make a total volume of 1. In addition, each sample containing the dye of the present invention does not cause changes over time such as discoloration or fading during aqueous solution preparation, emulsion preparation, or storage, and has no adverse effects on photographic properties such as fogging or desensitization, and has extremely excellent halation prevention. It was an effective photosensitive material.

Claims (1)

[Claims] 1. A photographic light-absorbing dye represented by the following general formula. general formula (In the formula, R ₁ and R ₂ may be the same or different,
Each represents a lower alkyl group, L represents a methine group which may be substituted with a lower alkyl group, and l is an integer 1.
Or represents 2. )