JPH0571059B2 - - Google Patents

Description

[Detailed description of the invention]

INDUSTRIAL APPLICATION FIELD The present invention relates to pyrimidine compounds. More specifically, the present invention relates to a novel pyrimidine compound useful as a heat-sensitive or pressure-sensitive recording material and a current recording display material. Conventional technology In the heat-sensitive recording method, a color forming agent and a color developer are uniformly dispersed, and then applied to a support and heated and melted to develop color.In the pressure-sensitive recording method, the color forming agent is dispersed in the form of fine microcapsules. It is applied to a support, placed on top of the support coated with a color developer, and pressure is applied to break the microcapsules, bringing the color former and developer into contact and producing color. Conventional leuco dyes such as triphenylmethane,
Fluoran and phthalide dyes have been used. The properties required of the coloring agent include the whiteness of the background before coloring, coloring sensitivity, coloring density, and fastness of the colored image such as light fastness, water resistance, and solvent resistance. There are few color formers (dyes) that satisfy all of these properties, and the triphenylmethane, fluoran, or phthalide dyes that are mainly used are colored by ring opening of a lactone ring, and the fastness of the colored image is limited. In particular, no dye has been found that exhibits sufficient quality in terms of water resistance. Further, in the current recording display method, a voltage is applied to cause a redox reaction in a substance within the system, thereby causing a reversible change in light transmittance. Conventionally, substances that cause redox reactions and reversible changes as described above are called electrochromic substances, and specific examples include inorganic transition metal oxides such as tungsten oxide, vanadium oxide, and iridylium hydroxide. etc. are organic viologen derivatives, tetrathiofulvalene derivatives,
Fluoran compounds, rare earth phthalocyanines, etc. are known. Electrochromic layers of these inorganic materials are usually prepared by applying vacuum deposition techniques such as vapor deposition or sputtering, but it is difficult to form a uniform and flexible metal oxide layer over a wide area. It is not easy to obtain. Furthermore, the display color is also limited to specific colors, such as blue for tungsten oxide and blue black for iridium hydroxide. In addition, although it is possible to select the color tone with organic materials such as those mentioned above, the contrast of the color tone is weak,
Further, problems have been pointed out such as slow response speed and low durability, and furthermore, these materials have the disadvantage that they are generally expensive compounds. Problems to be Solved by the Invention As a color forming agent in heat-sensitive or pressure-sensitive recording methods, it has excellent water resistance and light resistance after color development, and as an electrochromic substance in electrical recording display methods, it has a high color value and has a high color response. There is a need for fast, durable and inexpensive compounds. Means for solving the problem In order to obtain a dye (coloring agent) that provides images with excellent water resistance and light resistance in heat-sensitive or pressure-sensitive recording methods,
In addition, the present invention was developed as a result of extensive research in order to obtain an electrochromic material that has a fast response speed and is durable in the current recording display method.
That is, the present invention is based on the formula ()

[In the formula (), X is oxygen or sulfur, or R ₁ ,
R ₂ represents a methyl group or an ethyl group. In addition, benzene nucleus A is a chloro group, methyl group, ethoxy group, methoxy group or

[Formula] (R ₄ and R ₅ represent a methyl group, an ethyl group, a cyanoethyl group, a β-chloroethyl group, or an alkoxyalkyl group having 3 to 4 carbon atoms). ] It was discovered that the pyrimidine compound represented by is excellent as a dye (coloring agent) in heat-sensitive or pressure-sensitive recording methods, and as an electrochromic substance in electrical recording display methods, and the present invention was completed. It is something that In the present invention, the pyrimidine compound of the formula () is 7-N,N-dimethylamino- or 7-N,N-diethylamino-2-imino-coumarin-3-carbonamide of the following formula () or the pyrimidine compound of the formula () It is synthesized by condensing the 3-thiocarbonamide of formula ()' with the benzaldehyde of formula () in the presence of a catalytic amount of a base, and further tautomerizing the compound using an alkali if necessary.

[Chemical formula] (In the formula, X, R ₁ , R ₂ and A have the same meanings as above.) Coumarin carbonamide of formula () is a combination of cyanoacetamide and 4-N,N-dimethylamino- or 4-N, N-diethylamino-2-hydroxy-
Coumarin carbonamide of the formula ()' is obtained by condensing benzaldehyde in the presence of a base (catalyst), and the coumarin carbonamide of formula ()' is a known 7-N,N-dimethylamino- or 7-N,N-diethylamino-2-imino compound. It is synthesized by adding hydrogen sulfide to -3-cyanocoumarin. Specific examples of the benzaldehydes of formula () include benzaldehyde, 4-chloro-benzaldehyde, 4-methoxy-benzaldehyde, 4-
N,N-dimethylamino-benzaldehyde, 4
-N-methyl-N-cyanoethylamino-benzaldehyde, 4-N-methyl-N-β-chloroethyl-3-methyl-benzaldehyde, 4-N,
Examples include N-diethylamino-3-methoxy-benzaldehyde and 4,4-N,N-β-methoxymethylamino-benzaldehyde. The condensation of the coumarin derivative of formula () or formula ()' with the benzaldehyde of formula () is carried out in the presence of a catalytic amount of an organic base such as piperidine, pyridine, triethylamine, tributylamine, morpholine, etc. in an organic solvent such as toluene, xylene, In a solvent such as benzene, chlorobenzene, methylcellosolve, ethylcellosolve, etc. at 80-140℃, preferably at 100℃
It is carried out with heating to ~120°C, preferably with azeotropic removal of water. When cooled, the compounds of formulas () and () precipitate as crystals, so they are separated and, if necessary, further refluxed in alcohol, in the presence of caustic soda, sodium methylate, etc., to tautomerize them into formula (). . The piperidine compound of formula () of the present invention is a colorless to slightly colored compound, and it can be brought into contact with an acidic color developer, that is, an electron acceptor, or dissolved in an organic solvent containing a supporting electrolyte. Since it develops a reddish-orange to greenish-blue color when energized, it is useful as a dye (coloring agent) in heat-sensitive or pressure-sensitive recording methods, and as an electrochromic substance in energized recording display methods. The method of use thereof can be carried out by a known method. For example, in the heat-sensitive recording method, the pyrimidine compound of the present invention is used as a color former, and a phenolic substance such as bis-phenols or an acid clay substance such as bentonite is used as a color developer. The zeolites are separately finely dispersed in an aqueous polyvinyl alcohol solution, then mixed, applied uniformly onto high-quality paper, and dried to obtain a heat-sensitive recording material. When heated to bring the two into corrosive contact, color development occurs immediately, making it possible to obtain colored image recordings with superior water resistance and light resistance compared to conventionally known fluoran-based and phthalide-based color formers. In addition, in the pressure-sensitive recording method, the pyrimidine compound of the present invention is mixed with an oil agent, such as KMC-113 (manufactured by Kouha Kagaku Co., Ltd., Bis-
Isopropyl-naphthalene) is dissolved and added to an aqueous solution of gelatin, gum arabic, etc. to finely disperse and emulsify it, then acetic acid is added to adjust the pH to 4 to cause coacelvation, and formalin is added.
The microcapsule film is cured by adjusting the pH to 9 and heating it slightly, and it is uniformly coated on high-quality paper and dried to produce colored paper. On the other hand, active whiteness, acid clay,
Acidic substances such as phenolic resin, zinc 3,5-bis(α-methylbenzyl)salcylate, and zinc toluenesulfonate are dispersed in a vinyl acetate-maleic anhydride copolymer binder and spread uniformly on high-quality paper. Coat and dry to make color developing paper. When the two papers are overlapped and pressure is applied to bring the pyrimidine compound of the present invention into contact with an acidic substance, coloring occurs and a pressure-sensitive recorded image with superior light resistance compared to conventional phthalide-based fluoran coloring agents is obtained. I can do it. In addition, the energization recording display method involves dissolving the pyrimidine compound of the present invention and a supporting electrolyte (e.g., tetrabutylammonium tosylate, sodium dodecylbenzenesulfonate) in a solvent (e.g., dimethylformamide, acetonitrile, dioxane) to form a solution. is enclosed in a known energization display device (cell). The cell has a transparent upper electrode and a lower electrode separated by about 0.1 to 5 mm via a spacer. When a voltage is applied between the two electrodes and electricity is applied, the pyrimidine compound of the present invention is oxidized and develops a color. Discolors when energized. The pyrimidine compound of the present invention is characterized in that it has a wide range of color hues and has a quick color development response. Examples The present invention will be explained in more detail by examples. In the examples, "parts" represent "parts by weight." Example 1 19.3 parts of 4-N,N-diethylamino-2-hydroxy-benzaldehyde, cyanoacetamide
Add a few drops of piperidine to 8.4 parts of ethanol and stir under reflux for 2 hours. After cooling and separating the precipitated crystals, washing with a small amount of ethanol and drying, 7
25.2 parts of -N,N-diethylamino-2-imino-coumarin-3-carbonamide were obtained.
(mp192-193°C (decomposition)) 2.6 parts of 7-N,N-diethylamino-2-imino-coumarin-3-carbonamide. 1.5 parts of benzaldehyde and pyridine
0.2 parts in 15 parts of toluene with stirring to 110-115
The mixture was heated for 12 hours at ℃ while removing water azeotropically. Next, the reaction solution was cooled and the precipitated crystals were collected. 20 parts of ethanol and 3.5 parts of 28% sodium methylate were added thereto, and the mixture was stirred under reflux for 1 hour. Further, 5 parts of water was added and the mixture was stirred under reflux for 1 hour. After cooling, the reaction solution was poured into 300 parts of water and diluted hydrochloric acid was added to adjust the pH to 8 to 9.
After stirring, the precipitated crystals were separated, washed with water, and dried. 1.8 parts of a pyrimidine compound having the following structure was obtained as almost colorless to pale yellow crystals. mp287～
290℃ (recrystallized from alcohol)

[Chemical formula] When this compound was used as a color forming agent in pressure-sensitive recording by a conventional method, a red colored image with excellent light resistance was obtained. Example 2 2.6 parts of 7-N,N-diethylamino-2-imino-coumarin-3-carbonamide, 4-N,N
- 1.5 parts of diethylamino-benzaldehyde and 0.2 parts of piperidine in 110 parts of methylcellosolve
The mixture was heated and stirred at 120°C for 6 hours. Cool, separate the precipitated crystals, and add 20 parts of ethyl alcohol, 28%
The mixture was stirred at reflux for 2 hours with 2.5 parts of sodium methylate. Further, 5 parts of water was added and the mixture was refluxed for 1 hour, and the reaction solution was poured into 400 parts of water to separate the precipitate, which was washed with water.
Dry. A pyrimidine compound with the following structure was obtained as pale yellowish brown crystals. (mp335~340℃)

[Chemical formula] Example 3 7-N,N-diethylamino-2-imino-3
6.0 parts of -cyano-coumarin was dissolved in 20 parts of dimethylformamide, and a solution of 3.0 parts of 70% sodium hydrogen sulfide and 7 parts of water was added while stirring. 2.3 parts of acetic acid was added dropwise over about 30 minutes while stirring at 45-55°C, and after stirring at the same temperature for 30 minutes, it was poured into ice water.
350 copies were added. Separate the precipitated crystals and wash with water.
After drying, 6.3 parts of 7-N,N-diethylamino-2-imino-coumarin-3-thiocarbonamide were obtained. (MP200-203℃ (decomposition), recrystallized from ethyl alcohol) 7-diethylamino-2-imino-coumarin-
105 2.7 parts of 3-thiocarbonamide, 1.5 parts of benzaldehyde, and 0.2 parts of piperidine in 20 parts of toluene
Stirred at ~115°C for 6 hours while removing water azeotropically. After cooling, separate the precipitate and add 20 ml of ethyl alcohol.
1 part and 2.0 parts of 28% sodium methylate, and the mixture was stirred under reflux for 1 hour. After cooling, water
The precipitate was separated, washed with water, and dried.
2.0 parts of a pyrimidine compound having the following structure was obtained as light brown crystals. (mp207~211℃, recrystallized product from ethyl alcohol)

[Chemical formula] When this compound was used as a color former in a pressure-sensitive recording method, a red colored image with excellent water resistance was obtained. Examples 4 to 16 According to the method described in Examples 1 to 3, iminocoumarins of the following formula () formula ()' and formula ()
A pyrimidine compound of formula () was obtained by condensing benzaldehyde.

[ka]

【table】

【table】

[Table] Application example 1 25 parts of the target compound described in Example 1 and 25 parts of a 10% polyvinyl alcohol aqueous solution were ground with 50 parts of water in a ball mill for 24 hours to obtain a coloring solution, while 30 parts of bisphenol A and 10% polyvinyl Alcohol aqueous solution 30
1 part and 40 parts of water were ground in a ball mill for 24 hours to obtain a color developer solution. A mixture of 15 parts of color forming agent liquid and 85 parts of color developing agent liquid was uniformly applied to high quality paper so that the dry weight increased by 10%, and dried to obtain thermal paper. This thermal paper gave a deep orange-red colored image by heating with a thermal head, and the colored image had excellent water resistance and light resistance. Application example 2 Three parts of the target compound described in Example 2 was added to KMC-113.
(Kureha Chemical, bis-isopropylnaphthalene)
It was completely dissolved in 100 parts while heating. Separately, 20 parts of gelatin and 12 parts of gum arabic were added to 200 parts of water and dissolved while heating. The above KMC-113 solution was added to this solution with vigorous stirring, and the mixture was further stirred for 3 hours to form an emulsion. Add 700 parts of water, add acetic acid, adjust the pH to 4, generate coacelvation, cool and gel, 30% formalin solution 50%
After adding 50% of the solution, add caustic soda solution to adjust the pH to 9.
The capsule membrane was cured by heating to 40-50°C. This coloring liquid was evenly applied to high-quality paper so that the weight increase upon drying was 10%, and dried to obtain colored paper. Meanwhile, 50 parts of a 25% aqueous solution of sodium salt of vinyl acetate-maleic anhydride copolymer was added to 200 parts of water.
Next, 20 parts of zinc oxide, 60 parts of kaolin, and titanium oxide.
10 parts of zinc orthophenyl salicylate slurry (10% aqueous dispersion) were dispersed, and further 10 parts of styrene-butadiene latex was added for dispersion to prepare a color developer. This increases dry weight by 10% on high-quality paper.
It was coated uniformly so as to give a color developing paper and dried. When the microcapsules were destroyed by applying pressure when the two were stacked on top of each other, the area where the pressure was applied immediately developed a green-blue color. This colored image had excellent water resistance and light resistance. Application example 3 2 parts of the target compound described in Example 2 and 2 parts of tetrabutylammonium tosylate as a supporting electrolyte were dissolved in 40 parts of CMF, and a part of this was sealed in the empty cell shown in Figure 1 to create a energization display device. Obtained. Sweeping was performed while applying a voltage using the potential regulation method shown in FIG. When the lower electrode 6 of the energization display device was grounded and a positive voltage was applied to the upper electrode, a deep blue color appeared near the upper electrode at around +2.0V. When the voltage was swept in the opposite direction, the surface disappeared and became pale yellowish brown around -1.5V. The time period for coloring and fading was approximately 0.8 seconds. Effects of the Invention A pyrimidine compound was obtained which provides a thermally recorded image with excellent water resistance and light resistance, and which provides an energization display with a fast response speed.

[Brief explanation of drawings]

FIG. 1 shows an example of an electrochromic display device (ECD). FIG. 2 shows an example of a method for applying voltage to the ECD. In FIGS. 1 and 2, 1... Transparent upper substrate, 2... Transparent upper substrate, 3... Solution containing an EC substance and supporting electrolyte, 4... Spacer, 5...
Porous white plate, 6... lower electrode, 7... energization display device (cell), 8... potentiostat, 9...
...Cyclic wave oscillator.

Claims (1)

[Claims] 1 Formula () [In the formula, X represents oxygen or sulfur, and R ₁ and R ₂ represent a methyl group or an ethyl group. In addition, benzene nucleus A is chloro, methoxy group, ethoxy group, methyl group, or [Formula] group (R ₄ and R ₅ are methyl group, ethyl group, cyanoethyl group, β-chloroethyl group, or alkoxyalkyl group having 3 to 4 carbon atoms) A pyrimidine compound represented by the following.