JPH0362029A - Fluorescent whitening agent for silver halide photography - Google Patents

Abstract

PURPOSE:To obtain a silver halide photographic sensitive material having satisfactory sensitivity and ensuring an improved white ground by using a fluorescent whitening agent having a gelatin moiety and a fluorescent whitening agent moiety. CONSTITUTION:The fluorescent whitening agent having a gelatin moiety and the fluorescent whitening agent moiety is used. When the fluorescent whitening agent is incorporated into a photographic layer, the outflow of the agent from the layer to other layer is inhibited because the agent has both the moieties and the lowering of sensitivity during storage, the reduction of the whitening effect of the agent due to outflow to a processing soln. such as a color developing soln. during processing and other trouble can be prevented. The fluorescent whitening agent can be properly utilized in a reflective silver halide photographic sensitive material for direct appreciation so as to enhance whiteness.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a fluorescent brightener for silver halide photography. The fluorescent brightener of the present invention can be suitably used, for example, in reflective silver halide photographic materials for direct viewing to improve whiteness.

[Background of the invention]

In silver halide photography, especially in photographic materials intended for direct viewing, for example, the whiteness of the background has an important influence on the image quality.

Improved background whiteness increases contrast, improves color purity, and improves aesthetics. Therefore, various methods have been devised to improve whiteness.

Fluorescent brighteners are known as one of the effective means for improving the whiteness of silver halide photographic materials.

One way to use this fluorescent whitening agent is to include it in a color developing solution. It is stated in each publication of the issue. However, these methods have drawbacks such as insufficient fluorescent whitening effect and poor stability of the developer.

As a means to improve these drawbacks, there is a technique of incorporating a fluorescent brightener into a light-sensitive material.
No. 1189, No. 48-27592, No. 49-1069
No. 6, No. 51-28225, and No. 52-32254.

However, according to such conventional technology, during storage,
It is presumed that this is because the fluorescent brightener flows into other layers of the photographic constituent layers, but sensitivity may become insufficient. Further, there is a drawback that the fluorescent whitening agent flows out into a processing solution such as a color developing solution during processing, reducing the whitening effect.

[Purpose of the invention]

The present invention was made to eliminate the above-mentioned drawbacks of conventional fluorescent brighteners for silver halide photography, and an object of the present invention is to further improve the whiteness of silver halide photographic light-sensitive materials. A silver halide photographic fluorescent brightener that can improve the brightness of the image and is also suitable for rapid processing, and that can provide silver halide photographic light-sensitive materials with good sensitivity and improved white background. An object of the present invention is to provide a fluorescent brightening agent for photography.

[Means for solving problems]

The above object is achieved by a fluorescent brightener for silver halide photography, which is characterized by having a gelatin part and a fluorescent brightener part.
be accomplished.

It is believed that the fluorescent brightener of the present invention has a gelatin portion and a fluorescent brightener portion, thereby suppressing the addition of the fluorescent brightener from the photographic constituent layer to other layers. Although the effects of the present invention are not necessarily clear, due to the above properties,
It is presumed that the above-mentioned objects of the present invention have been achieved.

The present invention will be described in more detail below. Since the fluorescent brightener of the present invention has a gelatin part and a fluorescent brightener part, the fluorescent brightener for constituting the fluorescent brightener part is For convenience, the fluorescent brightener of the present invention will be referred to as the "compound of the present invention" in the following description.

First, the fluorescent whitening agent constituting the compound of the present invention will be described. This fluorescent whitening agent is a substance that absorbs ultraviolet light and emits fluorescent light that is usually slightly bluish, making objects appear whiter. Examples of fluorescent brighteners constituting the fluorescent brightener portion of the compound of the present invention include those used for photography, mainly to increase the whiteness of the substrate after processing of photographic paper. , any brightener may be used.

For example, Veen Rataramann [the Chemistry of Synthetic Dyes]
Compounds described in Chapter 8 of Volume V of Phys.

More specifically, stilbene compounds, coumarin compounds, biphenyl compounds, benzoxacylyl compounds, naphthalimide compounds, birapurin compounds, carbostyryl compounds, etc. may be mentioned.

These fluorescent brighteners can be synthesized, for example, by the usual method described in "Fluorescent Brighteners" edited by Kakaihin Kogyo Kyokai (published in August 1976).

Examples of fluorescent brighteners for constituting the fluorescent brightener portion preferably used in the present invention are shown below, but the present invention is not limited thereto.

The following margins W-1 j: W-2 W-3 W-4 FW-5 FW-6 ff-7 W-8 W-9 W-10 W-11 W-12 * -3OJ)lz W-13 1- 14 W-15 SOJ! W-16 W-17 W-18 FW-19 FW-20 W-21 FW-22 FW-23 F V/-24 W-25 W-26 ShinreiuuH 5 (hN squirrel 3N! FW'- 29 F Vl-30 WL31 W-32 1v-33 L Ch F W-34 F W-35 F Yr 36 F', l 37 F ?/-38 H W-42 W-44 W-45 W-46 W -47 F's'1-49 W-50 (,!1・υH W-51 W-52 W-53 The method for producing the compound of the present invention, that is, the method for combining gelatin and a fluorescent brightener, Any method may be used as long as it does not significantly impair the properties of the brightener.

Specific binding methods include, for example, "Chemical Modification of Collagen and Gelatin" by Harukazu Toyoda and Yasumasa Chonan: Leather Chemistry;
30 (1), 3 (1984), representative methods are listed below.

■) The α-amino group of the amino terminal amino acid of the polypeptide chain of gelatin or the ε-aξ group of the side chain of lysine or hydroxylysine residue, and the carboxyl group or alkoxycarbonyl group bonded to the fluorescent brightener, A method of reacting an aryloxycarbonyl group, a chloroformyl group, a chlorosulfonyl group, an isocyanate group, an isothiocyanate group, or a chlorocarbonyloxy group to form an amide bond, a sulfonamide bond, a ureido bond, a thioureido bond, or a urethane bond.

2) Carboxyl groups bonded to the main chain or side chain of gelatin (i.e., the α-carboxyl group of the carboxyl-terminal amino acid of the polypeptide chain of gelatin, the β-carboxyl group of the side chain of an aspartic acid residue, or the β-carboxyl group of the side chain of a glutamic acid residue) A method of activating a carboxyl group by acting a water-soluble carbodiimide on the T-carboxyl group, and then reacting it with an amino group or hydroxyl group bonded to a fluorescent brightener to form an amide bond or an ester bond.

3) The amino group, carboxyl group, or hydroxyl group bonded to the main chain or side chain of the water-soluble polymer and the amino group, carboxyl group, or hydroxyl group bonded to the fluorescent brightener, X, -L-x2 A method of linking using a compound having two reactive groups represented by:

Xl and X2 are carboxyl group, alkoxycarbonyl group, aryloxycarbonyl group, chloroformyl group,
Chlorosulfonyl group, isocyanate group, isothiocyanate group, chlorocarbonyloxy group, arylcarbonyloxy group, hydroxy group, amino group, fluorine atom, chlorine atom, bromine atom, iodine atom, alkylsulfonyloxy group and arylsulfonyloxy represents a group, L
is a divalent linking group such as a substituted and unsubstituted alkylene group,
Represents substituted and unsubstituted arylene groups and substituted and unsubstituted heterocyclic groups.

As a method for activating carboxyl groups, N, N'
-dicyclohexylcarbodiimide (DCC), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC), ■-cyclohexyl-3-(2-morpholinyl4-ethyl)carbodiimide meth-P-) Luenesulfonate (CMC), 1-benzyl 3-(3-
A method using a water-soluble carbodiimide such as dimethylaminopropyl) carbodiimide (BDC), a condensation reagent such as N-ethyl-5-phenylisoxazolium-3'-sulfonate (Woodward reagent K), and a method using a condensation reagent such as pentachlorophenyl chloroacetate (TCA). -OPCP), p-nitrophenyl trifluoroacetate (TFA-OPNP)
), an active ester method using P-nitrophenylchloroforsoate, etc., an acid chloride method using thionyl chloride, etc.

Synthesis examples of the compounds of the present invention are shown below.

Synthesis Example-1 300 ml of the above-mentioned exemplified brightener FW-23 was dissolved in 200 d of water, and the pH was adjusted to 4.5.

Then 1-ethyl-3-(3-dimethylaminopropyl)
- Add 500 mg of carbodiimide hydrochloride, pH 4,
The reaction was carried out for 30 minutes while maintaining the temperature at 7. After that, an additional 5%
Gelatin solution (solution in 0.1 molar phosphate buffer, pH 8.0) 150- was added and stirred at 40"C for 2 hours. After the reaction, dialysis, ultrafiltration, concentration, and lyophilization were performed to obtain the desired product. 6.2g was obtained.

The introduction rate of FW-23 was 3.1% by weight.

Compliance Example-2 150 ml of the above-mentioned exemplary brightener FW-32 was dissolved in 200 d of water, and the pH was adjusted to 4.5.

Then 1-ethyl-3-(3-dimethylaminopropyl)
- 500 μl of carbodiimide hydrochloride was added, and the mixture was reacted for 30 minutes while maintaining the pH at 4.7. After that, 5% gelatin R? 150 mf (0.1 mol phosphate buffer solution with pH 8.0) was added and stirred at 40°C for 2 hours. After the reaction, 5.5 g of the target product was obtained by dialysis, ultrafiltration, and freeze-drying.

The introduction rate of FW-32 was 1.7% by weight.

The compounds of the present invention can be used as fluorescent brighteners in silver halide photographic materials. In this case, it can be contained in any layer of the photosensitive material, but at least one of the silver halide emulsion layer and the adjacent hydrophilic colloid layer (intermediate layer, filter layer, antihalation layer, protective layer, undercoat layer, etc.) It is preferably contained in the layer.

The amount of the compound of the present invention added varies depending on the photosensitive material and the type of compound, but generally per layer of the photosensitive material,
The amount is preferably 1-Log, particularly preferably 100-5 g.

The fluorescent brightener of the present invention can be applied to various types of light-sensitive materials, such as those described below.

For example, photosensitive materials for general-purpose black and white use, plate making, color positive use, color paper use, reversal color use, direct positive use, heat development use, or silver halide with surface latent image type silver halide grains and internal fog nuclei. It can be used in photosensitive materials according to the method described in U.S. Pat. Nos. 2,996,382 and 3.178,282 using particles.
It is particularly advantageous to apply the present invention to reflective silver halide photographic light-sensitive materials for direct viewing having a multilayer structure.

The silver halide emulsion used in the light-sensitive material may contain any silver halide used in ordinary silver halide emulsions such as silver bromide, silver iodobromide, silver iodochloride, silver chlorobromide, and silver chloride. can be used.

The silver halide grains used in silver halide emulsions may have a uniform silver halide composition distribution within the grain, or they may be core/shell grains in which the silver halide composition differs between the inside and surface layer of the grain. good.

The silver halide grains may be such that the latent image is mainly formed on the surface, or may be such that the latent image is mainly formed inside the grain.

Silver halide emulsions may have any grain size distribution. Emulsions with a wide grain size distribution (referred to as polydisperse emulsions) may be used, or emulsions with a narrow grain size distribution (monodisperse emulsions) may be used. ) may be used alone or in combination. Further, a mixture of a polydisperse emulsion and a monodisperse emulsion may be used.

The silver halide emulsion may be a mixture of two or more separately formed silver halide emulsions.

The emulsion can be chemically sensitized by conventional methods, or optically sensitized to a desired wavelength range using a sensitizing dye.

Antifoggants, stabilizers, etc. can be added to the silver halide emulsion. Gelatin is advantageously used as binder for the emulsion.

The emulsion layer and other hydrophilic colloid layers can be hardened and can contain a plasticizer and a dispersion (latex) of a water-insoluble or sparingly soluble synthetic polymer.

A -1G coupler is used in the emulsion layer of the color light-sensitive material. Furthermore, by coupling with oxidized products of color and developing agents that have the effect of color correction, development accelerators, bleach accelerators, developers, silver halide solvents, toning agents, hardeners, fogging agents, and fogging agents can be produced. Compounds that release photographically useful fragments such as inhibitors, chemical sensitizers, spectral sensitizers and desensitizers can be used.

As the yellow dye-forming coupler, known acylacetanilide couplers can be preferably used.

Among these, benzoylacetanilide and pivaloylacetanilide compounds are advantageous.

As the magenta dye-forming puller, 5-pyrazolone couplers, pyrazoloazole couplers, open-chain acylacetonitrile couplers, isodasolone couplers, etc. can be used.

Phenol or naphthol couplers are commonly used as cyan dye-forming couplers.

The photosensitive material may be provided with auxiliary layers such as a filter layer, an antihalation layer, and an antiirradiation layer. These layers and/or the emulsion layers may contain dyes that are leached from the light-sensitive material or bleached during the development process.

A matting agent, a lubricant, an image stabilizer, a formalin scavenger-1 ultraviolet absorber, a fluorescent whitening agent, a surfactant, a development accelerator, a development retarder, and a bleach accelerator can be added to the photosensitive material.

As a support, paper coated with polyethylene, etc.
Polyethylene terephthalate film, baryta paper, cellulose triacetate, etc. can be used.

A known method can be used to develop the photosensitive material used in the present invention. Generally preferred treatment temperature is 18
It is used at a temperature between .degree. C. and 50.degree. C., and depending on the purpose, any of black and white photographic processing, lithographic development processing, or color photographic processing in which a dye image is formed can be applied. Further, photosensitive materials for thermal development are usually preferably processed at a temperature of 100°C or higher.

[Example] The present invention will be explained in more detail with reference to Examples below.
This is an example for explaining the present invention, and the present invention is not limited thereto.

Example 1 On a paper support laminated with polyethylene (containing titanium oxide, 12.7 g/rrr), the following layers were sequentially coated from the support side to produce silver halide color photographic materials Nα1 to Nα7.

Layer 1 - 1.2 g/gelatin, 0.
Blue-sensitive silver chlorobromide emulsion (silver chloride content 99.3 mol%), 0, sog/
0.80g/dissolved in dioctyl phthalate of rrf
Layer containing yellow coupler (Y-1) of rrf.

Layer 2---------1.0g/gelatin, 1
An intermediate layer comprising 0 .mu./bo of anti-irradiation dye (Al I), 5 .mu./bo of (AI-2), and a fluorescent brightener as described in Table 1.

Layer 3 - 1.25 g/rd gelatin, 0.228/rrf green sensitive silver chlorobromide emulsion (silver chloride content 99.5 mol%), 0.30 g/bo A layer containing 0.62 g/bo of magenta coupler (M-1) dissolved in dioctyl phthalate.

Layer 4 - Intermediate layer consisting of 0.9 g/po gelatin.

Layer 5...-1,40g/bo gelatin, 0.20
g/nf red-sensitive silver chlorobromide emulsion (silver chloride content 99.7 mol%), containing 0.9 mmol/bo cyan coupler (CI) dissolved in 0.20 g/bo dioctyl phthalate. layer.

Layer 6 - Intermediate layer consisting of 0.9 g/% gelatin.

Layer 7 - Layer containing 0,50 g/rrf of gelatin.

In addition, as a hardening agent, 2,4-dichloro-6-hydroxy-3-triazine sodium was added in layers 2.4 and 7.
Each was added in an amount of 0.017 g per 1 g of gelatin.

Margins below the table (Y-1) (M-1) (C-1) (AI 2) Each of the above photosensitive material samples was exposed through an optical wedge and then processed in the following steps.

Treatment process (35°C) color development bleach fixing Stabilization drying 45 seconds 45 seconds 1 minute 30 seconds 2 minutes 60~80″C The composition of each treatment liquid is as follows.

Color developer (per 1j2) Bleach-fix solution Heat and add water to bring the total volume to 11.

Stabilizing Solution> For each sample after the above treatment, the sensitivity of the green-sensitive emulsion layer was determined using sensitometry.

In addition, the reflection density of the unexposed area (white background area) at a wavelength of 650n11 was determined.

The above results are shown in Table-2.

Table 2 As is clear from Table 2, the samples of the present invention have good sensitivity and white background.

In addition, instead of the fluorescent brightener in sample 2, the above-mentioned FVI-
3, FW-6, FW-13, FW-30, FW32,
When samples were prepared using gelatin into which FW-40, FW-45, and FW-52 had been introduced and similar experiments were conducted, the effects of the present invention were confirmed.

Example 2 Using the samples Nα1 to Nα7 prepared in Example 1, each was exposed through an optical wedge and then treated in the following steps using the same treatment solution as in Example 1.

Processing steps Color development Bleach fixing at 38°C for 30 seconds Stabilization at 35°C for 30 seconds Drying at 60-80''C for 2 minutes For each sample after the above treatment, the reflection density of the white background area at a wavelength of 650 nm was determined.

The results are shown in Table-3.

Table 3 From Table 3, it can be seen that the samples containing the compound of the present invention do not impair white background even when rapidly processed, and have suitability for rapid processing.

[Effects of the present invention]

As mentioned above, by adding at least one compound selected from the compounds of the present invention used as fluorescent brighteners,
Further, a silver halide photographic material with improved whiteness and suitable for rapid processing can be obtained.

Claims (1)

[Claims] 1. A fluorescent brightener for silver halide photography, characterized by having a gelatin part and a fluorescent brightener part.