JPS6143703B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to photographic printing materials, and more particularly to photographic printing materials with improved whiteness. Generally, photographic printing materials have a photographic emulsion layer, an intermediate layer, a protective layer, etc. formed on an opaque support such as polyolefin laminated paper. As a means of brightening these photographic printing materials, for example, a white pigment such as rutile titanium oxide or anatase titanium oxide and a fluorescent whitening agent are added to the thermoplastic resin of thermoplastic resin-coated paper as a support. A method of adding in advance is commonly used. According to this method, even if the support itself is whitened, hydrophilic colloid layers such as a photographic emulsion layer, a protective layer, and an intermediate layer are coated on it. Especially in color photographic printing materials, blue-sensitive emulsions are usually used. layer, a green-sensitive emulsion layer, a red-sensitive emulsion layer, and an intermediate layer between each emulsion layer, and a protective layer on the top layer. In order to protect the image from deterioration caused by ultraviolet rays, it sometimes contains an ultraviolet absorber, and the whitening effect is currently greatly reduced. Therefore, various studies are being conducted to compensate for this lost whitening effect. One example is a method of adding a fluorescent brightener to a photographic emulsion layer, intermediate layer, protective layer, etc., but most of it is eluted from inside during various photographic processing processes, resulting in a satisfactory brightening effect. cannot be obtained. Even if the amount of fluorescent brightener added is increased in order to improve these drawbacks, the effect is not substantial, and other drawbacks arise, such as increasing static marks on the photographic printing material. Alternatively, there is a method in which a polymer compound having excellent adsorption properties for fluorescent brighteners is dispersed in gelatin and the fluorescent brightener is adsorbed thereto. As a specific polymer compound, Japanese Patent Publication No. 34-7127 discloses polyvinylpyrrolidone, U.S. Patent No.
3269840 describes polyvinyl-2-oxazolidone, and Japanese Patent Publication No. 39-22065 describes polyvinyl-2-oxazolidone.
N-vinyl-5-methyl-2-oxazolidinone, a copolymer of vinylpyrrolidone and other vinyl polymers is known from Japanese Patent Publication No. 43-22882. These polymer compounds have almost no effect when the degree of polymerization is low, and the higher the degree of polymerization, the stronger the whitening effect can be obtained. However, the high polymerization degree of the polymeric compound that provides the desired fluorescent whitening effect results in poor compatibility with gelatin, which is used as a hydrophilic colloid, resulting in coating failures during the manufacturing process of photographic printing materials, Even if it can be coated, in the case of photographic printing materials that have gloss, it may cause retardation and lose its gloss, and furthermore, it may have disadvantages such as poor adhesion resistance due to inhibition of the hardening reaction, so it is added. There are restrictions on the degree of polymerization and amount of the polymer compound to be used. Moreover, even if these methods are used, the fluorescent brightening agent still dissolves out of the material during various photographic processing steps, making it impossible to achieve the intended purpose. Also, special public service in 1977-
Publication No. 10696 describes a product made into a polymer using a known fluorescent brightener, but it is difficult to synthesize and is expensive, and has the same drawbacks as the above-mentioned polymer compounds. Also known is a method in which a fluorescent brightener is added to a photographic processing solution and the fluorescent brightener is adsorbed to hydrophilic colloids in the photographic printing material through processing.
However, gelatin, which is commonly used as a hydrophilic colloid, has a weak ability to adsorb fluorescent brighteners and requires a fairly high concentration of fluorescent brightener, resulting in high costs.
Also, depending on the photographic processing solution, the performance may deteriorate due to the addition of a high concentration of fluorescent brightener.
There is also the inconvenience of having to use an extra fluorescent brightening bath in addition to the normal photographic process. Furthermore, it is also impossible to uniformly and selectively adsorb the fluorescent brightener to the necessary constituent layers. Accordingly, a first object of the present invention is to provide a photographic printing material that has an excellent fluorescent whitening effect even after undergoing various photographic processing steps. Second aspect of the present invention
The object of the present invention is to provide a photographic printing material which is excellent in fluorescent brightening effect and also in gloss and adhesion resistance. A third object of the present invention is to provide a photographic printing material that exhibits an excellent fluorescent whitening effect even after processing with a photographic processing solution containing a small amount of a fluorescent brightener. A fourth object of the present invention is to provide a photographic printing material in which a fluorescent brightener is uniformly and selectively adsorbed to necessary constituent layers even after undergoing various photographic processing steps. Therefore, the term "photographic printing material" as used in the present invention includes not only unexposed materials but also materials that have been subjected to development treatment to form an image. Such an object of the present invention is to provide photographic printing materials containing acid-treated gelatin and a water-soluble fluorescent brightener.
achieved. That is, the present inventors have discovered that acid-treated gelatin is particularly excellent in its ability to adsorb water-soluble fluorescent brighteners, and have now completed the present invention. In general, substances called fluorescent brighteners are
It is a compound that absorbs ultraviolet light of 300 to 400 nm and emits part of the energy of this absorbed light as light of 400 to 500 nm. The fluorescent brightener used in the present invention is
Since many photographic printing materials have a yellowish tinge,
It is desirable to have a spectrum of emitted light, that is, fluorescent light, at its maximum wavelength in the range of 430 to 450 nm.
In addition, in the present invention, since the fluorescent whitening agent is directly adsorbed onto the hydrophilic colloid, the fluorescent whitening agent must be water-soluble, and has at least one sulfo group or a salt thereof as a hydrophilic group, or Those having a carboxyl group or a salt thereof are preferred;
Water-soluble fluorescent brighteners described in Japanese Patent No. 48-32963 and the like can be used. The water-soluble fluorescent brighteners used in the present invention include stilbene derivatives, diphenyl derivatives,
These include benzidine derivatives, benzothiazole derivatives, benzoxazole derivatives, benzimidazole derivatives, etc., and compounds represented by the following general formulas [] to [] are particularly preferably used. General formula [] [In the formula, A ₁ and A ₂ are each a hydrogen atom,
Represents a lower alkyl group, hydroxy group, carboxyl group or a salt thereof, or a sulfo group or a salt thereof, and B ₁ and B ₂ are each a hydrogen atom, (B ₃ and B ₄ each represent a hydrogen atom, a hydroxyl group, or a substituted or unsubstituted lower alkoxy group, aryloxy group, heterocyclic group, lower alkylthio group, arylthio group, thioheterocyclic group, or amino group) ), -NHCOB ₅ (B ₅ represents a substituted or unsubstituted lower alkoxy group, aryl group, aryloxy group, heterocyclic group, lower alkylthio group, thioheterocyclic group, or amino group, respectively.),

[Formula] group or

[Formula] (Y ₁ and Y ₂ each represent a group of nonmetallic atoms necessary to form a substituted or unsubstituted aromatic ring, and B ₆ represents a hydrogen atom or a substituted or unsubstituted lower alkyl group. ). ] General formula [ ] [In the formula, C ₁ and C ₂ are hydrogen atoms, respectively.
Represents a lower alkyl group, a lower alkoxy group, a halogen atom, a sulfo group or a salt thereof, or a carboxyl group or a salt thereof, and D ₁ and D ₂ are
Substituted or unsubstituted diphenyl group, α
-naphthyl group, β-naphthyl group, or

[Developer composition]

Meter 1.0g Anhydrous sodium sulfite 15g Hydroquinone 4g Sodium carbonate monohydrate 27g Potassium bromide 1.3g Add water to make 1. [Fixer composition] Crystalline sodium thiosulfate 240 g Anhydrous sodium sulfite 15 g Glacial acetic acid 13.3 g Borax 7.5 g Powdered potassium alum 15 g Add water to make 1. When the relative fluorescence intensity of these 15 types of treated samples was measured, the results shown in Table 1 were obtained.

【table】

[Table] As is clear from Table 1, compared to Samples Nos. 6 to 10 containing acid-treated gelatin according to the present invention, Comparative Samples Nos. 1 to 5 using only alkali-treated gelatin have significantly higher relative fluorescence intensities. is decreasing. On the other hand, comparative samples Nos. 11 to 15 containing polyvinylpyrrolidone, which has been frequently used up until now, maintain relative fluorescence intensity to some extent, but the gloss deteriorates significantly due to retickling. was. Example 2 Additives such as hardeners and coating aids were added to a silver halide emulsion containing 50 g of acid-treated gelatin and 20 g of silver chlorobromide (containing 30 mol% silver bromide), and then a photograph was prepared. Sample No. 16 was prepared by coating gelatin at 50 mg/dm ² on baryta paper and drying. On the other hand, as a comparison sample, Sample No. 17 was prepared by applying and drying the gelatin in the same manner using alkali-treated gelatin instead of the acid-treated gelatin used in Sample No. 16. Each of these two types of samples was divided into two parts and subjected to light wedge exposure, one was treated in the same manner as in Example-1, and the other sample was added to the developer in Example-1 with a fluorescence increase of 0.5g/. Whitening agent Whitex BB (manufactured by Sumitomo Chemical Co., Ltd., 4,4-diaminostilbendisulfonic acid derivative) was added, and exactly the same treatment was performed. The results of these treated samples are shown in Table 2.

[Color developer composition]

Composition (A) Benzyl alcohol 15ml Diethylene glycol 15ml Add water to make 40mg. Composition (B) Hydrosilamine sulfate 2 g Composition (C) N-ethyl-N-β-methanesulfonamidoethyl-3-methyl-4-aminoaniline sulfate 4.4 g Composition (D) Potassium carbonate 30 g Bromide Potassium 0.4g Anhydrous potassium sulfite 2g 1-hydroxyethylidene-1,1-diphosphonic acid 1.2g Potassium chloride 0.5g P-toluenesulfonic acid 10g Above compositions (A), (B), (C) and (D) Sequentially add, mix and dissolve in appropriate amounts of pure water, add water to bring the total volume to 1, and adjust the pH using sodium hydroxide.
Adjust to 10.1. [Bleach-fix solution composition] Ethylenediaminetetraacetate iron ammonium
61.0g Diammonium ethylenediaminetetraacetate
5.0g Ammonium thiosulfate 124.5g Sodium metabisulfite 13.3g Anhydrous sodium sulfite 2.7g Add water to make 1, and use ammonia water to adjust the pH.
Adjust to 7.2. [Stabilizing liquid composition] Add 20 ml of glacial acetic acid, 800 ml of water, and add sodium acetate.
After adjusting the pH to 3.5-4.0, add more water to bring it to 1. (Processing step-2) In the processing step-1, a stabilizing liquid containing 1 g of WF-13 is used. (Processing step-3) In the processing step-1, Chinopal is added to the stabilizing solution.
Use one containing 1g/MSP. (Note 1) Tinopal MSP (fluorescent whitening agent manufactured by Ciba Geigy) (Processing step-4) Color development (WF in the color developing solution of Processing step-1)
-11g/use the one containing)
3 minutes 30 seconds Bleach fixing 1 minute 30 seconds Washing with water 3 minutes 30 seconds (Processing step-5) Color development 3 minutes 30 seconds (Whitex BB (Sumitomo Chemical Co., Ltd. fluorescent whitening) in the color developing solution of Processing step-1 agent) 1
Bleach-fixing: 1 minute and 30 seconds Washing with water: 3 minutes and 30 seconds The relative fluorescence intensity of the obtained sample was measured, and the results shown in Table 3 were obtained.

【table】

[Table] As is clear from Table 3, the samples according to the present invention are color printing materials with excellent relative fluorescence intensity and excellent whiteness.

Claims (1)

[Claims] 1. A photographic printing material characterized by containing acid-treated gelatin and a water-soluble fluorescent brightener.