JPS5933904B2 - Silver halide color photographic material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a silver halide color photographic light-sensitive material, and more particularly to a silver halide color photographic light-sensitive material in which the dark fading resistance of a cyan dye image is improved.

In general, in silver halide photographic materials, exposed silver halide grains are developed with an aromatic primary amine developer, and a dye is formed by a coupling reaction between the oxidation product of the developer and a coupler. Form an image.

In this method, acylacetamide or benzoylmethane couplers are usually used for yellow, pyrazolone, cyanoacetyl or intazolone couplers for magenta, and phenol or naphthol couplers are used for cyan to form a dye image. The dye images formed in this way are not necessarily stable and are known to fade or change color due to humidity or heat when exposed to light for long periods of time or even when stored in the dark. There is. In particular, cyan dye images obtained from the phenolic or naphtholic cyan couplers are more sensitive to humidity, heat, or trace amounts when stored in the dark than yellow or magenta dye images obtained from other couplers. It is also known that chemical substances cause significant discoloration.

Such dark fading of dye images is a major hindrance when it is desired to semi-permanently preserve color photographs as records. Therefore, many improvement methods have been proposed as methods for preventing or stabilizing the fading of these dye images. Use of hydantoin compounds according to the description, U.S. Pat. No. 3,201,244
The use of the carbohydratide compound described in the specification of No. 3, the use of the cysteine compound described in the specification of US Pat. No. 3,201,243, the use of the polymethylol compound described in the specification of US Pat. No. 3,473,929, etc. This relates to a method of treatment by including it in a stabilizing bath.

Therefore, the above-mentioned method cannot meet the recent trend toward omitting stable bath treatment due to high-temperature and rapid processing, and is therefore not suitable for the following objectives of the present invention. Further, due to the fact that residual coupler that did not participate in the coupling reaction accelerates fading of the dye image, US Pat.
No. 1152 proposes the use of water-soluble Kabra. That is, a water-soluble coupler that substitutes a water-soluble group at the coupling position is dispersed in the emulsion layer, and although it has no solubilizing effect on the coupler itself, it has a strong solvent effect on the dye formed from the coupler. In this invention, a dispersion of a hydrophobic solvent such as a hydrophobic solvent having a fluorine content is also added to the emulsion layer, and unreacted residual couplers are washed away as water-soluble during processing. However, in the above method, the water-soluble coupler and the hydrophobic solvent must be separately dispersed in the emulsion layer, which is troublesome in terms of the manufacturing process and is not practical. On the other hand, according to JP-A-50-151149, a method for stabilizing a cyan dye image by using a cyan coupler in combination with a 2-(2-hydroxyphenyl)benzotriazole compound is proposed. The stability of the emulsified dispersion is poor, making it difficult to actually apply it to photosensitive materials.

On the other hand, as an invention relating to a method for improving the dark fading property of cyan dye images by using a coupler solvent,
26036 and JP-A-51-149028 are known, but the coupler solvents used in these methods are all high-boiling point solvents, such as citric acid derivatives and maleic esters. They do not show sufficient effects in improving the dark fading properties of cyan dye images, and are not necessarily satisfactory in terms of the stability of coupler dispersions.

Accordingly, a first object of the present invention is to provide a color photographic material in which the dark fading resistance of cyan dye images is sufficiently improved. A second object of the present invention is to provide a color photographic material having improved stability of cyan dye images without adversely affecting photographic properties such as fog, sensitivity, image density or sharpness. It is. A third object of the present invention is to provide a color photographic material with improved cyan dye image stability by emulsifying and dispersing a phenolic cyan coupler in a hydrophilic colloid layer using a solvent with good dispersibility. It is to provide.

A final object of the present invention is to provide a color photographic material with excellent cyan image stability and suitable for high-temperature rapid processing without the use of a stabilizing bath.

According to the present invention, a phenolic cyan coupler that is sparingly soluble in water is emulsified and dispersed in a hydrophilic colloid using only an organic solvent that is particularly sparingly soluble in water and has a low boiling point, and this coupler dispersion is It has been found that the above object can be achieved by including it in the silver halide emulsion layer. In addition,
In the present invention, the poorly water-soluble organic solvent refers to an organic solvent that can be dissolved in an amount of 257 or less per 100 y of water, particularly an organic solvent that can be dissolved in an amount of about 157 to 57 y per 100 y of water. is most preferred.

Furthermore, the term "low boiling point organic solvent" refers to an organic solvent having a boiling point of 125°C or lower, particularly preferably 100°C or lower.

Next, specific examples of advantageous poorly water-soluble and low boiling point organic solvents used in the present invention will be described, but the present invention is not limited to the use of the following organic solvents.

8. All of the above organic solvents are available as commercial products.

On the other hand, as the cyan coupler used in the present invention, a phenolic cyan coupler represented by the following general formula is particularly preferred.

"5!0 (In the formula, R1 is a hydrogen atom, a lower alkyl group, R2, R3
is a hydrogen atom, an alkyl group, an acylamino group, or an alkoxy group; It is.

) Specific examples of cyan couplers are listed below, but the present invention is not limited thereto.

The above cyan coupler is, for example, US Pat. No. 2,423,733.
0 specification, US Patent No. 2801171, US Patent No. 3758308, US Patent No. 3839044, JP 50-10135, JP 50-117422, and JP 51
They can be synthesized according to the methods described in JP-A-108841.

These cyan couplers can be added to the silver halide emulsion layer and used alone or in combination of two or more. These cyan couplers are generally added to a red-sensitive emulsion layer of a soluble plastic using 0.5 to 10 parts by weight of the low boiling point organic solvent according to the present invention per 1 part by weight of the cyan coupler. The amount ratio is preferably 5 to 30 mol % per mol of silver halide.

Next, as a method for adding a cyan coupler to a silver halide emulsion using an organic solvent according to the present invention, first, 0.5 to 10 parts by weight of an organic solvent that is sparingly soluble in water and has a low boiling point is used. 1 part by weight of cyan coupler is dissolved in a hydrophilic colloid solution to which a surfactant is added,
After emulsifying and dispersing using a colloid mill etc., the organic solvent is distilled off from this dispersion under reduced pressure and then added to the silver halide emulsion, or...the emulsified dispersion is added to the silver halide emulsion. However, the most preferred dispersion method is a method in which the organic solvent is removed by volatilization by coating and drying. The photosensitive emulsion layer containing the phenolic cyan coupler or other non-photosensitive hydrophilic colloid layer used in the present invention may contain known reducing agents or antioxidants, such as sulfites, hydroxylamines, and resorcinol. etc. can also be used together.

The layer structure of the Rogge silver heptide color light-sensitive material according to the present invention may be formed by the usual subtractive color method.In principle, a yellow coupler for forming a yellow dye in the blue-sensitive light-sensitive layer is
The basic layer structure is three layers, each containing a magenta coupler for forming a magenta dye in the green-sensitive photosensitive layer and a cyan coupler for forming a cyan dye in the red-sensitive photosensitive layer. Furthermore, any or all of these layers may be made into double or triple layers,
It is possible to improve various photographic properties of a light-sensitive material, such as color development characteristics, color reproducibility, and color pigment granularity.

In addition to these basic emulsion layers, layers such as a protective layer on the top layer, an intermediate layer between the layers, a single layer of filters, an undercoat layer and an anti-halation layer on the bottom layer are appropriately used to protect and prevent color contamination. It is possible to measure prevention, graininess improvement, color reproduction improvement, film adhesion improvement, etc.

The silver halide used in the color light-sensitive material according to the present invention includes conventional silver halide photographic light-sensitive materials such as silver chloride, silver bromide, silver iodide, silver chlorobromide, silver iodobromide, and silver chloroiodide. Any silver halide used in is included.

The above silver halide emulsion can be sensitized using a known chemical sensitizer.

As the chemical sensitizer, noble metal sensitizers, sulfur sensitizers, selenium sensitizers, and reduction sensitizers can be used alone or in combination. A known binder is used as the binder for silver halide.

Furthermore, the silver halide emulsion used in the present invention can be spectrally sensitized using a known sensitizing dye, if necessary. The above silver halide emulsions include 1-phenyl-5-mercaptotetrazole, 3-methylbenzothiazole, 4- hydroxy-6
Various compounds such as heterocyclic compounds such as -methyl-1,3,3a,7-tetraazaindene, mercapto compounds, metal salts, etc. can be added.

Further, the hardening treatment of the emulsion is carried out according to a conventional method.

A surfactant may be added alone or in combination to the above silver halide emulsion.

These surfactants include coating aids, emulsifiers, permeability improvers for processing solutions, antifoaming agents, antistatic agents, adhesive resistance agents, and various active agents for improving photographic properties or controlling physical properties. agent can be used. The color developing agent used in processing the color photosensitive material according to the present invention is an alkaline aqueous solution containing the developing agent and having a pH of 8 or more, preferably 9 to 12.

This aromatic primary amine developing agent as a developing agent is
It means a compound having a primary amino group on an aromatic ring and capable of developing exposed silver halide, or a precursor for forming such a compound. The above-mentioned developing agent is typically a P-phenylenediamine type developing agent, and the following are preferred examples.

4-amino-N-N-diethylaniline, 4-amino-
N-ethyl-N-β-hydroxyethylaniline, 3-
Methyl-4-amino-N-ethyl-N-β-methanesulfonamidoethylaniline, 3-methoxy-4-amino-N-ethyl-N-β-methoxyethylaniline, and salts thereof such as sulfate and hydrochloride , sulfite, P-toluenesulfonate, and the like.

Moreover, various additives can be added to these color developing solutions as necessary. After imagewise exposure of the color light-sensitive material according to the present invention and color development processing, bleaching processing can be carried out by a conventional method. This treatment may be done simultaneously with fixing or separately. This processing solution can also be used as a bleach-fixing bath by adding a fixing agent if necessary. Various compounds can be used as bleaching agents, and various additives including bleaching accelerators can also be added. The color photosensitive material according to the present invention includes all kinds of color photosensitive materials such as color negative film, color positive film, color reversal film, and color paper. EXAMPLES Next, the present invention will be specifically explained using examples, but the embodiments of the present invention are not limited thereby.

Example 1 An exemplary cyan coupler (C-1) according to the present invention was placed on a polyethylene resin coated baryta paper, dibutyl phthalate, which is a known organic solvent, and an exemplary low boiling point organic solvent (2) according to the present invention, Using (4) and (5),
It is dissolved in the quantitative relationship as shown in Table 1 below.

This solution was mixed into a 5% gelatin solution containing Alkanol B, dispersed with a colloid mill, and then the low boiling point organic solvent was removed with an evaporator, added to red-sensitive silver chlorobromide emulsion 2007, and hardened. After adding the agent, the coating was dried.

Samples 1 to 4 were exposed to light through a step wedge for sensitometry, and developed using the following processing steps.

Table 2 shows the results of sensitivity measurements for samples 1 to 4.

In the table below, the sensitivity is expressed as a relative value when the sensitivity of sample 1 is set as 100. According to Table 2, sample 2 in which the coupler was dispersed using only the low boiling point organic solvent according to the present invention.
It can be seen that Samples 4 to 4 all have the same photographic performance as Sample 1 in which the coupler was dispersed using a high boiling point organic solvent.

Next, Samples 1 to 4 that had been developed were exposed to heat for two weeks at a temperature of 60°C and a relative humidity of 80%.
The dye images were similarly stored for two weeks in a dry state at 7° C., and the durability and stability of the respective dye images were examined.

The dye image durability was evaluated using the percentage of dye remaining after processing at an initial density of D - 1.0.

In addition, the degree of green discoloration is Blue/Red after the heat resistance test at the initial density D-1.0 and Blue before the heat resistance test.
/Red. Table 3 below shows the results of the heat resistance test regarding the durability of the cyan dye image and the degree of green discoloration. From Table 3, it is clear that Samples 2 to 4, which were dispersed using a low-boiling point organic solvent according to the present invention, have a greater persistence of cyan dye and green discoloration than Sample 1, which was dispersed using a high-boiling point organic solvent. It is understood that this has been improved.

Example 2 After dissolving cyan coupler in the composition ratio shown below on polyethylene resin-coated baryta paper, alkanol B was dissolved.
The dispersion was mixed in a 5% gelatin solution containing 10% gelatin, dispersed in a colloid mill, and the low-boiling organic solvent was removed in an evaporator.The dispersion was added to red-sensitive silver chlorobromide emulsion 200y, a hardener was added, and the mixture was coated and dried. .

Samples 5 to 8 thus obtained were exposed and developed in the same manner as in Example 1 to obtain cyan dye images.

These colored dye images were stored for two weeks at a temperature of 60° C. and a relative humidity of 80%, and for two weeks under dry conditions at a temperature of 77° C., to examine the storage and stability of the dye images. In addition, the numerical values in the table are values obtained by the same method as in Example 1. From Table 5, it can be seen that the cyan coupler of the present invention is superior to the sample dispersed using only a low boiling point organic solvent, which is a feature of the present invention, than the sample dispersed using a combination of a high boiling point organic solvent and a low boiling point organic solvent. It can be seen that the persistence of the dye image and green discoloration are clearly improved.

(Comparison with Samples 7 and 8) On the other hand, with cyan couplers other than the present invention, even when dispersed only with the low boiling point organic solvent of the present invention, no improvement effect on dye image storage stability or green discoloration was observed. Ta.

(Comparison with Samples 5 and 6) Example 3 A color print paper was prepared by sequentially coating layers 1 to 6 with the following compositions on polyethylene resin coated baryta paper.

(First layer) As a 2-equivalent yellow coupler, α-pivaloyl-α-(2,4-dioxo-1-benzylimidazolidin-3-yl)-2-chloro-5-[α-(2,4
Di-Tert-amylphenoxy)-butyramide]-
Acetanilide 57 is dissolved in a mixed solvent of dibutyl phthalate 5y and acetic acid ethyl ester 10r, and this is mixed into a 5% gelatin solution containing alkanol B.

Next, the dispersion was dispersed in a colloid mill, added to blue-sensitive silver chlorobromide emulsion 200f, a hardener was added, and the mixture was coated and dried. (Second layer) Intermediate layer consisting of gelatin.

(Third layer) As magenta couplers, 1-(2,4,6-trichlorophenyl)-3-[(3-octadecenylsucciimide)-anilino]-5-pyrazolone 3y and 1,4-dioctyl Oxy-2-dodecyl-5-methylhydroquinone 1y was dissolved in a mixed solvent of 37 dibutyl phthalate and 10 t of ethyl acetate, mixed into a 5% gelatin solution containing alkanol B, and dispersed with a colloid mill. It was added to 200 r of green-sensitive silver chlorobromide emulsion, a hardener was added, and the mixture was coated and dried.

(4th layer) 2,5-diTert-octylhydroquinone, 2-(
benzotriazol-2-yl)-4,6-diTert
-A gelatin layer containing 50▼/ml of each of -butylphenol and 2-(benzotriazol-2-yl)-4-Tert-butylphenol.

(Fifth Layer) The exemplified cyan coupler (C-2) according to the present invention was mixed with dibutyl phthalate and the exemplified low boiling point organic solvent (2) according to the present invention in a composition ratio as shown in Table 6 below, or , dissolved only in the above low-boiling point organic solvent, mixed in a 5% gelatin solution containing alkanol B, dispersed in a colloid mill, and then removed the low-boiling point organic solvent in an evaporator to obtain red-sensitive silver chlorobromide emulsion 2007. Multilayer coating samples 9 and 10 were prepared by adding a hardening agent and coating and drying.

(6th layer) A protective layer made of gelatin.

The obtained multilayer coating samples 9 and 10 were subjected to decomposition exposure through a step wedge using a red filter, and developed in the same manner as in Example 1 to form a cyan dye image.

In the red-sensitive emulsion layer obtained by dispersing the coupler using only a low-boiling point solvent, the stability of the resulting cyan dye image in the heat-and-moisture test, even for samples coated in multiple layers, was determined by the use of high-boiling point organic solvents. It showed better results than when used.

On the other hand, after leaving the same coupler dispersion liquid used for the fifth layer in this example at 5°C for one week,
The precipitation property of the coupler, that is, the stability of the dispersion liquid was investigated using a SEP-PL type turbidity meter manufactured by K and an optical microscope with a magnification of 600 times.

The results were as shown in Table 7 below.

' From Table 7, sample 10 of the dispersion method using a low boiling point organic solvent according to the present invention has superior dispersion stability even when changing over time, compared to the dispersion method using a high boiling point and low boiling point mixed solvent. I understand.

Claims (1)

[Scope of Claims] 1 A silver halide emulsion in which a phenolic cyan coupler represented by the following general formula is dissolved and dispersed using only an organic solvent that is sparingly soluble in water and has a boiling point of 102°C or less as a coupler solvent. A silver halide color photographic material that can be coated in at least one layer. General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R_1 is a hydrogen atom, a lower alkyl group, R_2,
R_3 is a hydrogen atom, an alkyl group, an acylamino group, an alkoxy group, X is a hydrogen atom, a halogen atom, an alkyl group,
The alkoxy group, Y is a group that leaves during the coupling reaction with the oxidized product of the color developing agent, and n is 1 to 3. ).