JPH0437980B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a diazo-based photosensitive material that is free from photofading. Conventionally, it has been known to use a hydrazone compound as a coupler for a diazonium salt in diazo-based photosensitive materials. (For example, JP-A-54-
(See Japanese Patent Nos. 30023, 35723, and 35724) These couplers can produce stable gray or bluish black images even if the developing conditions vary slightly. However, conventional diazo photosensitive materials, including commercially available so-called diazo photosensitive papers, have the disadvantage that they are susceptible to fading when exposed to actinic radiation for a long period of time after image formation. That is, the formazan dye produced by the coupling of a diazonium salt and a hydrazone compound fades when exposed to actinic radiation over a long period of time. In order to solve the above conventional problems, the present inventors conducted extensive research, focused on the ligand ability of formazan dyes, and completed the present invention. That is, the gist of the present invention is as follows. Diazonium salts and hydrazone compound couplers and coupling products in which diazonium salts can undergo electrophilic reactions with nickel, zinc, cobalt,
A hydrazo compound is a compound represented by the following general formula (), and is composed of a metal salt selected from the group of copper, manganese, europium, iron, silver, cadmium, chromium, titanium, molybdenum, tungsten, and germanium, and is a compound that produces coupling. An image-forming composition comprising 1 to 10 moles of the above metal salt per mole of the compound. R ₁ −CH=N−NH−R ₂ ……() (However, R ₁ :

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[Formula] [R ₃ :

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[Formula] -SO ₃ Na R ₄ , R ₅ : H, CH ₃ and C ₂ H ₅ may be the same or different. n: An integer from 0 to 12. ] _R2 :

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[expression] or

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【formula】 【formula】

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[Formula] [X is a counter ion]) In other words, in the present invention, by chelating the formazan dye, which is a coupling product of a diazonium salt and a hydrazone compound, it was possible to significantly stabilize the formazan dye image. It is. The most common and basic compound among formazan derivatives is represented by the following general formula (A). This compound (A) has an imino group proton that can be substituted with a metal. Therefore, the presence of the metal salt chelates with the metal and stabilizes the dye image. In the above general formula (A), 1,3,5-triphenylformazane in which R ₁₁ , R ₁₂ and R ₁₃ are all phenyl groups reacts with metal ions such as copper and nickel, but the reaction is slow. On the contrary,
In general formula (A), R ₁₁ and R ₁₃ are aryl groups, and compounds in which a hydroxyl group, a carboxyl group, an arsonic acid group (-A _{SO 3} H ₂ ), etc. are attached to the 0-position of the aryl group are copper, nickel, It reacts rapidly with metal ions such as cobalt and silver, resulting in a remarkable color change to blue, purple, green, or black. Therefore, as for the formazan dye to be coupled and produced in the composition of the present invention, it is more preferable that R ₁₁ and/or R ₁₃ contain a functional group in the case of general formula (A). Formazan dyes with functional groups react with metal ions to produce brightly colored chelates. That is, a formazan dye into which a functional group has been introduced forms a chelate with a metal, and a 1:1 chelate with metal M represented by the following formula (B) has been isolated. such compounds
(B) is an unsaturated compound that does not fully satisfy the metal coordination requirements, and can be bonded with another of the same reagents or other ligands. The copper chelate of compound (B) is yellow-green, but when pyridine is added, it becomes purple. Nickel chelate is yellow-green in color and becomes red when pyridine is added. When this yellow-green chelate is extracted with chloroform, it turns red and moves to the chloroform phase, which is thought to be due to the coordination of chloroform or impurities therein. The same thing is true for cobalt. However, it is true that dye images are more stable by creating metal chelates than if they are not. Furthermore, 1,5-di-(2-
In carboxyphenyl)-3-phenylformazane (of formula (c) below), one carboxyl group is said to be unrelated to chelate formation. Formazan interacts with the nitrogen of imino and azo groups.
This reagent is a tridentate ligand if it forms a chelate with the functional group in the 0-position of R ₁₁ or R ₁₃ . Although one molecule of the reagent neutralizes the charge of the divalent metal, the coordination number is not satisfied and is not appropriate. Next, 1,3 with a heterocyclic compound attached to R ₁₃
Considering a compound such as -diphenyl-5-2-pyridylformazane (of formula (D) below), the reagent in this case is also a tridentate ligand, but there is only one proton that can be substituted with the metal. Therefore, in order to neutralize the charge of a divalent metal, it is necessary for two molecules of the reagent to bind. In this case, the coordination number of the metal is 6, and it can be said that it is a convenient compound that satisfies the coordination number of many metals. In addition to this compound (D), 1-2-carboxyphenyl-3- having a functional group at R ₁₁ is added.
In a compound such as phenyl-5-2-pyridylformazane (formula (E) below), the charge is neutralized with just one molecule, and if it is sterically reasonable, it has a coordination number of 4 as a tetradentate ligand. It can be said that it is a more convenient compound because it satisfies the metal coordination requirements. In general, compounds in which a heterocyclic compound with a nuclear nitrogen at position 2 enters R ₁₁ and R ₁₃ have a large shift in the maximum absorption wavelength when chelated.
The shift is about 150 nm, but for compounds without a heterocycle, the shift is only about 50 to 80 nm. The molar extinction coefficient at the measurement wavelength is only about 1 to 2 x 10 ⁴ compared to about 3 to 4 x 10 ⁵ for heterocyclic compounds, so compounds with heterocycles form stable chelates, and zinc, cadmium, etc. It also reacts well with mercury, etc. The fact that all donor atoms are nitrogen is thought to improve selectivity, making them a useful group of compounds. In formazan, when a chelate is formed, the metal becomes stuck in the shape, so the "cage effect" that the metal of exactly the same size is stabilized is caused by zinc (ion radius: 0.74 Å).
seen in 1,5-di-(2-hydroxyphenyl)-3-cyanoformazane of the above formula (F) forms a very stable chelate. Although such stabilized formazan dye chelates can be bidentate chelates,
It has been observed that the highest stabilization due to chelation is obtained when the formazan dye is a tridentate chelate. In chelation, light fastness can be obtained by combining a formazan dye and a metal salt, and the color can be adjusted. Metal salts used for this purpose include, for example, nickel, zinc, cobalt,
Salts of metals such as copper, manganese, europium, iron, etc. may be mentioned. In addition to greater stability, chelated formazan dyes have another advantage.
That is, the dye typically exhibits a greater absorption in the red region than that of non-chelated formazan dyes. Therefore, high image density can be obtained, and furthermore, the chelated formazan dye has a significant blue tint and forms images with larger midtones. Next, as a particularly preferred example, highly stable 3
Table 1 shows hydrazone compounds that can form a formazan dye chelate.

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[Table] Hydrazone compounds generally have a yellowish tint, but Nos. 21 to 63 in the table are white and are good for image formation. In addition, these vidrazone compounds have one more
It was found that this method has two advantages. In other words,
The background area is less likely to discolor after image formation.
Common, for example benzaldehyde phenylhydrazone, exhibits weak photochromism. That is,
Hydrazone excited by ultraviolet light becomes pale pink due to hydrogen transfer, and exhibits so-called photochromism, returning to the original hydrazone in the dark or under heat. However, if the hydrazone side of the hydrazone is a heterocycle and the aldehyde side is an aliphatic aldehyde, this reaction is extremely difficult to occur as described in the Examples. This is particularly useful as an imaging composition. The hydrazone compound of the present invention can be easily obtained by reacting an aldehyde compound and a hydrazone compound as shown in the following formula. (In the formula, R ₁ and R ₂ are as described above.) The method for synthesizing the hydrazone compound according to the present invention is illustrated below. Synthesis method: 1 n-laurylaldehyde-2-benzothiazole hydrazone (No. 28) 2-hydrazinobenzothiazole 5.0 g
(0.0303 mol) and 100 ml of ethanol into a flask, and while stirring, n-lauryl aldehyde 5.78
(0.0303 mol) and a solution of 10 ml of ethanol was added dropwise little by little. If stirring is continued for 1 hour after the dropwise addition, crystals will precipitate out. The crystals were redissolved in a water bath, gravity filtered, and the filtrate was recrystallized. The precipitated crystals were filtered and recrystallized with ethanol. yield
10.0g (yield 65%) of wax-like, colorless, wool-like needle-shaped crystals with a melting point of 99-101°C. 2 n-Laurylaldehyde-2-pyridylhydrazone (No.39) 2-hydrazinopyridine 4.0g (0.0367mol),
Put 40ml of ethanol and 1ml of glacial acetic acid into a flask.
6.8 g of n-lauryl aldehyde while stirring
(0.0367 mol) and 10 ml of ethanol solution was added dropwise little by little. After continuing stirring for 1 hour, the precipitate was redissolved in a hot water bath, an appropriate amount of water was added so that the precipitate did not come out, and gravity filtration was performed, and the filtrate was recrystallized. The precipitated crystals were filtered off and recrystallized repeatedly from an ethanol/water mixed solvent. The yield was 10.1 g (yield 82%), and the product was wax-like, colorless, and malt-like crystals, and the melting point was 57 to 58.5°C. Other hydrazone compounds are also prepared by the same synthesis method as above, but the alkyl of the aliphatic aldehyde is small, such as n-propyl aldehyde and 2
-When reacting hydrazinobenzothiazole, adding a small amount of tetrahydrofuran in addition to alcohol will make the reaction go better. If the alkyl group of the aliphatic aldehyde is long, adding 1 drop of concentrated hydrochloric acid or 1 ml of glacial acetic acid will improve the yield. Additionally, adding a small amount of zinc chloride to the reaction solution will increase the yield. As the diazonium salt to be used with the hydrazone compound of the present invention, any diazo compound used in ordinary diazo copying materials can be used, but typical ones are as follows. 4-Diazo-2,5-dimethoxyphenylmorpholine, 4-diazo-2,5-diethoxyphenylmorpholine, 4-diazo-2,5-dipropoxyphenylmorpholine, 4-diazo-2,5-di Butoxyphenylmorpholine, 4-diazo-2,5-dibutoxy-N-benzyl-N-ethylaniline, 4-diazo-2,5-dibutoxy-N,N-dibutylaniline 4-diazo-2,5-dibutoxy- N-benzyl-N-hydroxyethylaniline, 4-diazo-2,5-dibutoxyphenylpiperidine, 4-diazo-3-methoxyphenylpiperidine, 4-diazo-2,5-diethoxyphenylpyrrolidine, 4 -Diazo-2,5-dipropoxyphenylpiperazine, 4-diazo-N,N-dimethylaniline, 4-diazo-N,N-diethylaniline, 4-diazo-N-ethyl-N-hydroxyethylaniline, 4 -Diazo-N,N-dipropylaniline, 4-diazo-phenylmorpholine, 4-diazo-phenylpyrrolidine, 4-diazo-2-methylphenylpyrrolidine. In addition to the above-mentioned nickel, zinc, cobalt, copper, manganese, europium, and iron, examples of metal salts that can chelate with the formazan dye, which is a coupling product, include silver, cadmium, chromium, titanium, molybdenum, tungsten, and germanium. Preference is given to using salts. When such a metal salt is coupled with a diazonium salt to hydrazone, it instantly chelates with the generated formazan, producing a vivid high-density image. The metal salt may be included in the photosensitive layer of the image recording medium, in a multilayer structure, in another adjacent layer, in another image recording medium, or in the developing bath. I can do it. ,
is the most practical, but care must be taken that metal salts may act as acidic or amphoteric, which may hinder the coupling of diazonium salts.
The amount is 1 to 10 per mole of formazan dye.
Double mole is good. Furthermore, various methods can be used to form an image by coupling a hydrazone compound and a diazonium salt and chelating a formazan dye and a metal salt. The most practical method is to immerse it in a basic developer or to spray it with a basic gas. Image formation by this method was also described in detail in Examples. As another method, a known heat development method can be used. This method has also been put to practical use on ordinary diazo photosensitive paper. Alternatively, a method can be used in which printing is colored using an image-like thermal pattern, and the diazonium salt in the non-image areas is decomposed and fixed using ultraviolet rays. Furthermore, after the composition of the present invention is provided on a normal hydrophilic medium, and an image is formed by image exposure and the above-mentioned development method, the hydrophilic medium is A hydrophobic image can be formed thereon and used as a printing plate. Further, in the present invention, known additives can be used in order to improve the storage stability of the image recording composition. This additive includes naphthalene mono,
Sodium di- or tri-sulfonate, sulfosalicylic acid, urea, thiourea, tartaric acid, citric acid,
Malic acid, malonic acid, caffein, thiophyllin, saponin, etc. are used. In order to explain the present invention in more detail, test examples and examples are shown. Test examples 1 to 10 6.0g of cellulose acetate, tetrahydrofuran
80 ml and the formazan dye listed in Table 1 obtained by alkali coupling of a normal diazonium salt to hydrazone prepared by the method shown in the synthesis example.
2.0×10 ^-3 mol was uniformly dissolved, and 1.5
A solution consisting of ×10 ⁻³ mol of the metal salt shown in Table 1 and 20 ml of ethanol was mixed to prepare a resin solution of a chelated formazan dye. Since the primary purpose of this test example is to compare the photobleaching properties of the formazan dye with those of the tridentate chelate of this dye, it is unnecessary to form the formazan dye in a thin film according to the method of the present invention. I thought it was. Spread 100 μm of each resin solution onto 10 μm thick Mylar.
It was applied with a thick metal blade and dried. The film thickness was 22 μm±2. The maximum absorption wavelength (λmax) and image density were measured for each element. After setting the image on a fade meter equipped with a carbon arc lamp (Long Life Fade Meter Model FA-3 manufactured by Suga Test Instruments Co., Ltd.) for 3 hours, the image density of each element was measured again. The results of comparing the initial image density and calculating the photofading % are shown in Table 1.

[Table] Examples 1 to 16 Photosensitive layer forming solutions 1 to 16 were prepared by mixing the following components. Table hydrazone compounds: 2 x 10 ^-3 mol 4-diazo-2,5-dibutoxy-
: 2×10 ^-3 mol n-phenylmorpholine BF ₄ Citric acid : 2 g Naphthalene-1,3,6-trisulfone
: 1 g Sodium acid Thiourea : 0.5 g Nito 2-hydroxy-3-naphthoic acid : 1 g Roanilide Table 1 Metal salt 4×10 ^-3 mol/Ether : Total solution volume Nord 20 ml solution Methyl cellulose : 5 g Dioxane : 80 ml above Photosensitive layer forming solutions 1 to 16 were applied to a triacetate film and dried to obtain a photosensitive film. The original drawing with the image is superimposed on each photosensitive film, and a commercially available diazo copying machine (Ricoh SM-
1500) (that is, using a dry copying machine), and the results of the images obtained are listed in Table 1. The % fading in the table is the result calculated under the same conditions as the test example. In the table, the image color tone is different from Test Examples 1 to 10 due to chelation in the alkaline development atmosphere, and most of the images are brighter.

[Table] Examples 17 to 21 Photosensitive layer forming liquids 17 to 21 were prepared by mixing the following components. Table hydrazone compounds: 2 x 10 ^-3 mol 4-diazo-2,5-diethoxyf
: 2×10 ^-3 mol Enylmorpholine chloride 1/2ZnCl _2- tartaric acid: 1 g Caffeine: 2 g Naphthalene-1,3,6-trisyl: 1 g Sodium phonate Zinc chloride: 4×10 ^-3 mol Water: 100 ml Layer forming solutions 17 to 21 were applied to ordinary white base paper for photosensitive paper and dried to obtain a photosensitive material. Each of the copying materials was divided into two parts, subjected to image exposure in the same manner as in the test example, and developed using a developer (2) prepared by mixing the following components and ammonia gas to form images. The respective results are listed in the table below. Developer solution (): Potassium carbonate: 2g Potassium metaborate: 3g Water: 100ml

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Claims (1)

[Scope of Claims] 1. Diazonium salts and hydrazone compound couplers and coupling products in which the diazonium salts can undergo electrophilic reactions, and nickel, zinc, cobalt, copper, manganese, europium, iron, silver, cadmium, chromium, titanium, and molybdenum. , tungsten, and a metal salt selected from the group of germanium, and the hydrazone compound is a compound represented by the following general formula (), and the coupling product 1
An image-forming composition comprising 1 to 10 moles of the above metal salt per mole. R ₁ −CH=N−NH−R ₂ …() (However, R ₁ : [Formula] [Formula] [Formula] [R ₃ : [Formula] [Formula] −SO ₃ Na R ₄ , R ₅ : H , CH ₃ , and C ₂ H ₅ may be the same or different. n: An integer from 0 to 12.] R ₂ : [Formula] [Formula] or [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [Formula] [X is a counter ion])