JPS6119985B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Field of Application) The present invention relates to photographic processing methods. The details relate to improved bleaching methods. In particular, it relates to an improved method or composition as described above, characterized in that it uses a bleaching accelerator that increases the bleaching power. (Prior Art) Generally, the basic steps in processing silver halide color photographic materials are a color development step and a desilvering step. That is, the exposed silver halide color photographic material is subjected to a color development process. Here, silver halide is reduced by a color developing agent to produce silver, and the oxidized color developing agent reacts with a color former to provide a dye image. However, later on,
Color photographic materials are subjected to a desilvering process. here,
After the silver produced in the previous step is oxidized by the action of an oxidizing agent (commonly called a bleaching agent), it is dissolved and removed by a silver ion complexing agent, commonly called a fixing agent. Therefore, only dye images are produced in photographic materials that have undergone these steps. In addition to the two basic steps of color development and desilvering mentioned above, the actual development process includes auxiliary steps to maintain the photographic and physical quality of the image, or to improve the storage stability of the image. Contains. For example, a hardening bath to prevent excessive softening of the photosensitive layer during processing, a stopping bath to effectively stop the development reaction, an image stabilizing bath to stabilize the image, or a decoating bath to remove the backing layer of the support. Examples include bathing. Further, the above-mentioned desilvering step may be carried out in one step using a bleach-fixing bath containing both a bleaching agent and a fixing agent, or may be carried out in two steps, a bleaching bath and a fixing bath, using separate baths. Generally, red blood salt is used as an oxidizing agent in bleaching solutions. However, the disadvantages of bleaching solutions using red blood salts are that the bleaching solution must be replaced when it is exhausted, and that felician ions and their reduced forms are emitted due to overflow during processing and carried into the washing water after bleaching. ferrocyanide ions undergo photochemical oxidation to produce cyanide compounds. These cyanide compounds are highly toxic and cause great harm. On the other hand, potassium dichromate, ferric ion complex salts, persulfates, quinones, copper salts, etc. have traditionally been used as bleaching agents other than red blood salts, but they have weak oxidizing power and are difficult to handle. It has its drawbacks. In recent years, ferric ion complex salts (e.g., aminopolycarboxylic acid ferric ion complex salts, etc., especially EDTA-iron() complex salts) have been used in color photographic materials, from the viewpoint of rapid and simple processing and prevention of environmental pollution. Bleaching treatment methods are mainly used. However, the disadvantage of bleaching baths using ferric ion complex salts is that they require a long time for bleaching due to their weak bleaching power. Therefore, it is desirable to increase the bleaching power (or oxidizing power) of bleaching solutions using ferric ion complex salts. (Objectives of the Invention) The first object of the present invention is to obtain a novel bleaching accelerator that does not adversely affect photographic properties, and a color photographic processing method for bleaching using the same. The second object is to obtain a rapid color photographic processing method using such a bleach accelerator. The third object is to obtain a method for rapidly bleaching color photographic materials having photographic sensitivity. (Structure of the Invention) As a result of various studies, the present inventors found that in a color photographic processing method in which an exposed silver halide color photographic light-sensitive material is subjected to at least a color development treatment and a desilvering treatment, bleaching containing a ferric ion complex salt is necessary. The above object was achieved by a color photographic processing method characterized by containing a compound of the following general formula in a bath or a pre-bath. general formula n is 1 or 2. R ₁ and R ₂ are hydrogen atoms,
Lower alkyl group having 1 to 2 carbon atoms or 1 to 3 carbon atoms
(However, R ₁ and R ₂ are not both hydrogen atoms.) A preferred compound is one in which either R ₁ or R ₂ is -COCH ₃ or -COC ₂ H ₅
and the other one is a hydrogen atom or R ₁ ,
R ₂ is also a compound that is CH ₃ or C ₂ H ₅ . Specific examples of the compound of the above general formula used in the present invention include the following:
The present invention is not limited to these exemplified compounds. The compounds of the present invention are excellent bleach accelerators in bleaching solutions containing ferric ion complex salts. The compounds of the present invention can be easily synthesized by known synthesis methods, and typical synthesis examples are shown below. Synthesis method of compound (1) 76g of thiourea is dissolved in 250ml of ethanol, 500ml of an ethanol solution of 143g of N-(2-chloroethyl)-dimethylamine hydrochloride is added thereto, and the mixture is heated under reflux for 6 hours. After reaction, cool and add 1000ml of ethyl acetate.
After adding a mixture of ligroin and ligroin (250 ml), the crystals are collected and recrystallized from absolute ethanol to obtain thiuronium salt. Yield 88gr (48%) mp174~5℃. Next, add 33g of the obtained thiuronium salt to 300ml of cold water.
Dissolve it in water and add 100ml of an aqueous solution containing 6gr of sodium hydroxide to hydrolyze it. The reaction solution is salted out, extracted with 500 ml of ether, dried, and distilled under reduced pressure to obtain the desired product. bp3 108℃ Yield 5.6gr (15%). Synthesis method of compound (4) 77 gr of 2-aminoethanethiol is dissolved in 300 ml of acetic acid, and 200 ml of acetic anhydride is gradually added dropwise thereto under stirring. After dropping, heat on a hot water bath for 1.5 hours,
Cooling. After acetic acid and acetic anhydride are distilled off, an acetyl compound is obtained by distillation under reduced pressure. bp2.5 114-118℃ Yield 71.4gr (60%). Dissolve 12g of acetyl body in 20ml of ethanol, and add 10.3g of 33% hydrogen peroxide solution dropwise while cooling.
After concentration under reduced pressure, the reaction product becomes candy-like and crystallizes when left standing. mp87℃ Yield 8gr (33%). Other compounds can also be synthesized according to these synthesis methods. The bleaching accelerator used in the present invention can be added to the bleaching bath or prebath (bath after color development and before bleaching treatment) at any concentration depending on the type of compound and purpose, but approximately 2% per solution. ×10 ^-6 to about 2 × 10 ^-1 mol is often used as a guide, preferably 1 × 10 ^-4
It is used in a range of 5×10 ⁻² mol. The complex salt of ferric ion used as a bleaching agent preferably uses an organic compound as a ligand, especially an organic chelating agent such as aminopolycarboxylic acid, aminopolyphosphonic acid, or a salt thereof. Those using polycarboxylic acids or salts thereof are preferred because they are inexpensive and have relatively little risk of causing pollution. These bleaching solutions are superior in that they do not have the following disadvantages of red blood salt bleaching solutions. In other words, bleaching solutions that use red blood salt are: firstly, the bleaching solution must be replaced when it is worn out, and secondly, ferrician complex ions are discharged due to overflow during processing or carried into the washing water after bleaching. Another disadvantage is that the ferrocyanide complex ions undergo photochemical oxidation to produce highly toxic cyanide compounds, causing great harm. Examples of these aminopolycarboxylic acids and aminopolyphosphonic acids or salts thereof are listed below. Namely, ethylenediaminetetraacetic acids (ethylenediaminetetraacetic acid and its disodium salt, diammonium salt, tetra(trimethylammonium) salt, tetrapotassium salt, tetrasodium salt, trisodium salt, etc.), diethylenetriaminepentaacetic acid, (diethylenetriaminepentaacetic acid, pentasodium salt, etc.), ethylenediamine-N-(β-oxyethyl)-N・N′・N′-triacetic acid (this acid, its trisodium salt, triammonium salt, etc.), propylenediaminetetraacetic acid (this acid, its trisodium salt, triammonium salt, etc.), acid and its disodium salt, etc.), nitrilotriacetic acids (this acid and its trisodium salt, etc.), cyclohexanediaminetetraacetic acids (this acid and its disodium salt, etc.), other iminodiacetic acids, dihydroxyethylglycine, Ethyl ether diamine tetraacetic acids, glycol ether diamine tetraacetic acids, ethylenediaminetetrapropionic acids, phenylenediaminetetraacetic acids, 1,3-diaminopropanol-N・N・
N', N'-tetramethylenephosphonic acids, ethylenediamine N, N, N', N'-tetramethylene sulfonic acids, 1,3-propylenediamine-N,
N・N′・N′-tetramethylenephosphonic acids, etc. Examples of bases that form salts with aminopolycarboxylic acids and aminopolyphosphonic acids include caustic alkali (alkali metal hydroxide), ammonia, and amines. Alkali metals include sodium, potassium, lithium, etc.; amines include alkylamines such as methylamine, diethylamine, triethylamine, and butylamine;
Ring amines such as cyclohexylamine, arylamines such as aniline, m-toluidine, and heterocyclic amines such as pyridine, morpholine, piperidine. The ferric ion complex salt may be added to the bleach bath in the form of a complex. Also, ferric salts (e.g. ferric sulfate, ferric chloride, ferric nitrate, ferric ammonium sulfate, ferric phosphate, etc.) and chelating agents such as aminopolycarboxylic acids or aminopolyphosphonic acids. A ferric ion complex salt may be formed in the solution by adding it to the bleach bath. When added in the form of a complex, one type of complex salt or two or more types of complex salts may be used. On the other hand, when forming a complex in a solution using a ferric salt and a chelating agent, one or more types of ferric salts may be used. Furthermore, one type or two or more types of chelating agents may be used. Further, in either case, the chelating agent may be used in excess of the amount required to form a complex of ferric ions. In this case, the amount of ferric ion complex per bleach bath is from about 0.1 to about 2 moles. The pH of the bleach bath is
In use, it is desirable that it be between about 3.0 and about 8.0, particularly between 4.0 and 7.0. In addition to the ferric ion complex salt and the new bleach accelerator, the bleach bath used in the present invention contains halides [for example, ammonium is an alkali metal (e.g., sodium or potassium) bromide, chloride, or iodide]. It is. Among these, bromides are particularly preferred. ] is preferably included. The appropriate amount of halide is about 50 to 300 g per bleaching solution. The bleaching solution of the present invention further contains pH buffering agents such as boric acid, borax, sodium metaborate, acetic acid, sodium acetate, sodium carbonate, potassium carbonate, phosphorous acid, phosphoric acid, sodium phosphate, citric acid, sodium citrate, and tartaric acid. It is possible to add one or more inorganic acids, organic acids, and salts thereof, and further sulfites (eg, sodium sulfite, potassium sulfite, ammonium sulfite, etc.). When the chemicals used in the above bleaching bath are used in combination with the bleaching accelerator of the present invention, an excellent bleaching agent composition can be prepared. The bleaching solutions or compositions thereof described above can be used in the bleaching process or as a replenisher for the bleaching solution in use. The present invention can be applied to the processing of all color light-sensitive materials using silver halide, such as color paper, color negative film, color reversal film, and color positive film, and can enhance the effect of promoting desilvering. The present invention is more effective for color negative films and color reversal photosensitive materials, and is particularly effective for color reversal photosensitive materials. When the bleaching accelerator of the present invention is added to the above-mentioned bleaching solution or a pre-bath (for example, the second stop bath), silver can be sufficiently bleached in a short period of time. The iodine content in silver iodobromide in the silver halide color photographic light-sensitive material used in the present invention is not particularly controlled, but is preferably about 1 to 8 mol%, particularly 3 to 7 mol%.
Mol% is preferred. The processing steps for color reversal sensitive materials are usually, for example, black and white development (bath) → stop (bath) → washing with water → fogging (bath).
→ Water washing → Color development (bath) → Stop (bath) → (During film (bath)) → Water washing → Bleaching (bath) → Water washing → Fixing (bath) →
The order is washing with water → stabilization (bath) → drying. Further, a pre-bath, a pre-hardening bath, a neutralization bath, etc. can be provided during these steps. On the other hand, a stabilizing bath, washing with water before and after bleaching, etc. can be omitted from the above steps. The fogging bath may be a treatment bath containing t-butylamine borane, sodium borohydride, or Sn() complex, and the color development may be carried out after being fogged before color development. Also, by adding a fogging agent (eg, t-butylamine borane, sodium borohydride, etc.) to the color developer, the fogging bath can be omitted. Also,
Fog bath can be replaced with re-exposure. The treatment temperature in each treatment step can be about 20°C to 70°C, preferably 30°C to 60°C. When the color photosensitive material to be processed is a reversal color photosensitive material, it may be an "inner type" photosensitive material containing a coupler in a photographic emulsion, or an "outer type" photosensitive material containing a coupler in a color developing solution. Good (in short, the present invention is particularly applicable to reversal color sensitive materials of any practical design) Color developer, black and white developer (for color reversal processing)
As the stop liquid, fixing liquid, etc., commonly used ones can be used. For example, as a color developing solution for color reversal processing, those mentioned in the examples are typical, but in addition to this, for example, ethylenediamine can also be added to this developer. The processing steps for color negative photosensitive materials are usually in the following order: color development (bath) → bleaching (bath) → fixing (bath) → washing → stabilization (bath) → drying. Further, during these steps, a stop (bath), hardening (bath), water washing, etc. may be provided between color development and bleaching, and water washing may be provided between bleaching and fixing. On the other hand, the stabilizing bath can also be omitted from the above steps. The treatment temperature in each treatment step can be about 20 to 70°C. As the color developing solution, stop solution, hardening solution, stabilizer, etc., commonly used ones can be used. In addition, regarding photographic silver halide emulsions and other hydrophilic colloid liquids that can be used in color sensitive materials processed by the color processing method of the present invention, their preparation methods, and photographic additives (or photographic materials), etc. , “Research Disclosure” magazine No. 92 (December 1971)
) Those described on pages 107 to 110 can be used as appropriate. EXAMPLE A color reversal photographic material was prepared by coating each layer in the following order on a triacetate film base. 1st layer (red-sensitive emulsion layer) Coating solution: red-sensitive silver iodobromide emulsion (silver iodide: 7 mol%) and cyan coupler emulsion (1-hydroxy-4-chloro-2-n as cyan coupler)
-dodecylnaphthamide, dibutyl phthalate as the coupler solvent) are mixed at a silver/coupler molar ratio of 8.0. Coated silver amount: 1.5gAg/ ^m2 . 2nd layer (intermediate layer) A gelatin intermediate layer containing di-t-amyl hydroquinone dispersed therein. 3rd layer (green-sensitive emulsion layer) Coating solution: Green-sensitive silver iodobromide emulsion (silver iodide: 6 mol%) and magenta coupler emulsion (1-(2,4,6-trichlorophenyl) as magenta coupler) -3-[3-(2,4-di-t-amylphenoxyacetamide)benzamide]-5-
pyrazolone, tricresyl phosphate as the coupler solvent) and the silver/coupler molar ratio
Mix to make 9.5. Coated silver amount: 1.5gAg/m ² 4th layer (yellow filter layer) A filter layer consisting of yellow colloidal silver and gelatin. 5th layer (blue-sensitive emulsion layer) Coating solution: Blue-sensitive silver iodobromide emulsion (silver iodide: 6 mol%) Yellow coupler emulsion (as a yellow coupler α-pivaloyl-2-chloro-5-
[γ-(2,4-di-t-amylphenoxy)butanamide] acetanilide and dibutyl phthalate as a coupler solvent are mixed so that the silver/coupler molar ratio is 8.01. Coated silver amount: 0.9gAg/ ^m2 . 6th layer (protective layer) A protective layer mainly composed of gelatin. After this color reversal film was exposed to light (1/100 second exposure through a light wedge using a tungsten lamp as a light source), the following reversal process was performed. Processing process Temperature Time first development (black and white) 37°C 3 minutes stop 37°C 2 minutes water washing 37°C 2 minutes color development (including brushing agent) 37°C 6 minutes stop 37°C 2 minutes washing 37°C Bleach for 2 minutes at 37℃ Wash for 6 minutes Fix at 37℃ for 2 minutes Wash with water for 2 minutes at 37℃ Stable for 2 minutes at 37℃ - Dry for 30 seconds at 37℃ Composition of first developer Sodium sulfite 60.0g 1-Phenyl-3 -Pyrazolidone 0.3g Hydroquinone 5.0g Sodium carbonate (monohydrate) 41.0g Potassium bromide 2.0g Potassium iodide (1% aqueous solution) 1.0ml Rodan potassium (1N aqueous solution) 10.0ml Sodium hydroxide (10% aqueous solution) 2.0 Add ml water 1.0 Composition of stop solution Sodium acetate 30g Glacial acetic acid 8ml Add water Total volume 1

【table】

[Table] Composition of fixing solution Sodium thiosulfate 150g Sodium sulfite 15g Borax 12g Glacial acetic acid 15ml Potassium alum 20g Add water Total volume 1 Composition of stabilizer Formalin (37%) 10c.c. Fuji Drywell 5c.c Bleaching was carried out for 6 minutes with the bleaching solution described above and a solution to which 1 g each of the compound of the present invention (with the compound number shown above) or 1 g of the comparative compound was added. The amount of silver remaining in the film after processing (at two locations, the highest density area and the lowest density area) was determined by fluorescent X-ray analysis, and the results are shown in the table.

[Table] Compound (A) in the table is [-SCH ₂ CH ₂ CH ₂ NH ₂ ] ₂
(1.0g/) From this result, the bleaching solution (C-1) according to the present invention ~
It can be seen that when (F-1) is used, desilvering is promoted compared to the comparative example (A-1) that does not contain the compound of the present invention or the case that contains comparative compound A (B-1). . Example A color reversal film similar to that in the example was exposed in the same manner as in the example and subjected to the following treatments. That is, in the processing step, instead of the second stop bath after color development, a pre-bath containing the accelerator of the present invention is used as described below for 2 minutes before bleaching, and then the bleaching bath is carried out without washing with water. (The accelerator of the present invention was not particularly added) was treated in the same manner as in Example except that the treatment was carried out for 6 minutes. After the treatment, the amount of silver remaining in the film was determined in the same manner as in the examples. The results are shown in the table. Pre-bath Sodium acetate 20g Each additive of the present invention or comparative compound (see table)
1g Add a small amount of glacial acetic acid (for pH adjustment) and water 1 PH5.5±0.2

[Table] Note that the same Comparative Compound A as in the Examples was used. From this result, when using the pre-baths (C-2) to (F-2) containing the bleach accelerator of the present invention, the pre-bath (A-2) containing no additive or the comparative compound A was used. It can be seen that desilvering was significantly promoted compared to the prebath (B-2). Embodiments of the present invention are described below. (1) A color photographic processing method according to the claims, wherein the ferric ion complex is an aminopolycarboxylic acid ferric complex salt. (2) The silver halide color photographic material has at least one silver halide photographic emulsion layer on the support, and the silver halide emulsion layer has an iodine content of about 1 to 8 mol%. A color photographic processing method according to the claims, comprising a silver iodide emulsion. (3) The color photographic processing method according to claim 1, wherein the content of the bleaching accelerator in the bleaching bath or pre-bath is 2×10 ^-6 to 2×10 ^-1 mol/. (4) The color photographic processing method according to the claims, wherein the content of the bleaching accelerator in the bleaching bath or pre-bath is 1×10 ^-4 to 5×10 ^-2 mol/. (5) The compound represented by the general formula is (1), (2), (3), (4)
or (5), the color photographic processing method according to the claims. (6) The content of ferric ion complex salt in the bleaching bath is approximately
0.1 to 2.0 mol/color photographic processing method according to the claims.

Claims (1)

[Scope of Claims] 1. In a color photographic processing method in which an exposed silver halide color photographic light-sensitive material is subjected to at least a color development treatment and a desilvering treatment, in a bleaching bath containing a ferric ion complex salt or a pre-bath thereof, A color photographic processing method characterized by containing a compound of the following general formula. [n is 1 or 2. R ₁ and R ₂ are hydrogen atoms, lower alkyl groups having 1 to 2 carbon atoms, or 1 to 3 carbon atoms
represents an acyl group, provided that both R ₁ and R ₂ are not hydrogen atoms. ] 2 The compound of the general formula is A color photographic processing method according to claim 1.