JPH0676559B2 - Pyrimidine compounds - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a pyrimidine compound useful as a dye for heat-sensitive and pressure-sensitive recording materials, electric recording display materials and the like.

2. Description of the Related Art The thermosensitive recording method is a method in which a color former and a developer are evenly dispersed and applied onto a support, and the mixture is heated and melted to develop a color. It is applied to a support as microcapsules, the support coated with a color developer is superposed on it, and pressure is applied to break the microcapsules.
The two are brought into contact with each other to develop color. As the color former, leuco dyes such as triphenylmethane type fluorane type and phthalide type dyes are used. Therefore, as a color developing agent, various properties such as whiteness of the background before coloring, coloring sensitivity, coloring density, light resistance after coloring, water resistance, solvent resistance, etc. are required, but coloring that satisfies all of these The above-mentioned dyes which are used as a mainstream with a small amount of agents have a color development accompanied by cleavage of a lactone ring, and no dye showing sufficient properties in water resistance has been found.

In addition, the energization record display method utilizes the property that a certain substance causes a redox reaction when a voltage is applied, and reversibly changes the light transmittance, and as a conventional substance such as an electrochromic substance. Are known to be inorganic transition metal oxides such as tungsten oxide, vanadium oxide, and iridium hydroxide, and organic materials such as viologen derivatives, tetrathiofulvalene derivatives, fluorane compounds, and rare earth phthalocyanines. ing.
Since the inorganic material forms the electrochromic layer by using a vacuum deposition technique such as vapor deposition or sputtering, it is not easy to obtain a uniform and flexible metal oxide layer over a wide area. The display color is limited to a specific color such as blue for tungsten oxide and blue black for iridium hydroxide. Further, although it is possible to select a color tone with an organic substance, it has been pointed out that the contrast of the color tone is weak and the response speed is slow, and the durability is not sufficient, and these compounds are generally expensive compounds.

Problems to be Solved by the Invention As a color former for heat-sensitive and pressure-sensitive recording materials, water resistance after color development,
A dye (precursor) having excellent light resistance is required, and as an electrochromic substance for a current recording display material, a dye having a high color value, a high color development response speed, and a durable and inexpensive dye is required. .

Means for Solving Problems In order to obtain a color developing agent which gives an image excellent in water resistance and light resistance as a heat and pressure sensitive recording material, an electrochromic substance having a fast response speed of a current recording display material is used. As a result of earnest studies, the present invention has been achieved. That is, the present invention has the formula (I) (However, in the formula, R ₁ and R ₂ are hydrogen, chlorine, a methoxy group, an ethoxy group, a methyl group or R ₃ R ₄ is a methyl group, an ethyl group, a cyanoethyl group, β
A chloroethyl group or an alkoxyalkyl group having 3 to 4 carbon atoms. The X is _{- (CH 2) 4 -,} - (CH 2) 5 - or -C ₂
H ₄ OC ₂ H ₄ −), which is extremely excellent as a color former in heat and pressure sensitive recording, and as an electrochromic material in electric recording display Is.

Thus, the pyrimidine compound of formula (I) in the present invention is condensed with benzo-2-imino-3-cyano by condensing 2-hydroxynaphthalaldehyde and malononitrile in the presence of a catalytic amount of an organic base as shown in the following steps. -Coumarin, which is easily synthesized by heat-condensing approximately equivalent amounts of benzaldehydes of the formula (II) and secondary amines of the formula (III) in alcohols.

(In the formula, R ₁ R ₂ X has the above meaning) Examples of the benzaldehyde of the formula (II) include, for example, benzaldehyde, 4-chloro-benzaldehyde, and 2,4-
Dimethoxybenzaldehyde, 4-NN-diethylamino-benzaldehyde, 4-N-methyl-N-cyanoethylamino-benzaldehyde, 4-N-methyl-β-chloroethylamino-3-methyl-benzaldehyde, 4
Specific examples thereof include -NN-diethylamino-3-methoxy-benzaldehyde and 4-NN-di (β-methoxyethyl) amino-benzaldehyde.

Further, as the secondary amines of the formula (III), pyrrolidine,
Examples include piperidine and morpholine. The condensation of benzo-imino-cyano-coumarin with benzaldehydes of the formula (II) and secondary amines of the formula (III) is carried out at approximately 40 to 100 ° C. in an alcohol solvent such as methanol, ethanol or methyl cellosolve. If you heat and stir at
If necessary, tettrium methylate, caustic soda, caustic potash, etc. may be added.

The pyrimidine-based compound of the formula (I) according to the present invention is a colorless to slightly yellow-brown colored compound, which is brought into contact with an acidic developer, that is, an electron acceptor or a supporting electrolyte. It is a compound useful as a color former for heat-sensitive and pressure-sensitive recording materials and as an electrochromic material for electric current recording display because it develops red-orange or blue-green color when dissolved in an organic solvent containing it and applied with electricity.

The method of use thereof is a known method, for example, a thermal recording method, a pyrimidine compound of the present invention as a color former, and a phenolic substance such as a bisphenol as a developer, an acid clay substance such as bentonite, a zeolite. Separately finely dispersed in a polyvinyl alcohol aqueous solution, mixed, coated on a fine paper and dried to obtain a recording paper. This recording paper can be heated to 100 ~ 1 by thermal head etc.
When heated to 40 ° C. and the color developer and the color developer are brought into molten contact with each other, the color is immediately developed, and a recorded image having excellent water resistance can be obtained as compared with the known fluoran-based and phthalide-based color developing agents.

In the pressure-sensitive recording method, the pyrimidine compound (color former) of the present invention is dissolved in an oil agent, for example, KMC-113 (Kureha Chemical Co., Ltd., diisopropylnaphthalene), and this is added to an aqueous solution of gelatin or arabic gum under stirring to obtain a fine particle. After emulsifying and dispersing
Add acetic acid to PH = 4 to induce coacervation, add formalin to adjust PH = 9 and heat slightly.
Cure the microcapsule membrane. This is applied evenly to a high-quality paper and dried to give a colored paper. On the other hand, activated clay, acid clay, phenol resin, zinc 3,5-bis (α-methylbenzyl) salicylate, zinc toluenesulfonate, etc. are used as binders such as vinyl acetate, maleic anhydride copolymer (developing agent), etc. Disperse in and apply evenly on high-quality paper, dry, and make color paper. When both are superposed, pressure is applied to break the capsule film and the color developer and developer are brought into contact with each other to develop color, and a recorded image with excellent light resistance is obtained compared to the conventional phthalide or fluoran color developer. You can get it.

Further, the energization record display method includes a pyrimidine compound of the present invention and a supporting electrolyte such as tetrabutylammonium tosylate,
Sodium dodecylbenzene sulfonate is dissolved in a solvent such as dimethylformamide, acetonitrile dioxane, etc. to form a solution, which is enclosed in a current-carrying display device (cell). In the cell, the transparent upper electrode and the lower electrode are separated by a spacer of about 0.1 to 0.5 mm. When a voltage is applied between both electrodes and electricity is applied, the pyrimidine-based compound of the present invention is oxidized to develop a color, and is decolored by applying electricity in the opposite direction. The pyrimidine-based compound of the present invention is characterized by abundant hues of color development and quick color development response.

EXAMPLES The present invention will be described in more detail by way of examples.

In the examples, "part" means "part by weight".

Example 1 2-Hydroxy-1-naphthaldehyde 8.6 parts Malononitrile 3.3 parts was stirred in 40 parts ethanol to give piperidine 3
Add drops and stir with heating at 40 ± 2 ° C for 1 hour. After cooling, the precipitated crystals are separated, washed with a small amount of alcohol and dried to obtain 10.8 parts of benzo-2-imino-3-cyano-coumarin having the following structure (a). (Mp219-220 ° C) benzo-2-imino-3-cyano-coumarin of (a) 2.
2 parts, 1.3 parts of benzaldehyde and 0.8 part of pyrrolidine are heated and stirred in 20 parts of ethanol at 40-45 ° C. for 1 hour at 75 ± 3 ° C. for 30 minutes. After cooling, the precipitated crystals are separated, washed with a small amount of ethanol and dried. 2.0 parts of an imidazole derivative having the following structural formula (b) was obtained. (Mp224-230 ° C) This compound was almost colorless crystals, and when used as a color former in a pressure-sensitive recording method, a red recorded image having excellent light fastness was obtained.

Example 2 2.2 parts of benzo-2-imino-3-cyano-coumarin (a) described in Example 1, 2.0 parts of 4-N-methyl-N-cyanoethylamino-benzaldehyde and 0.8 part of pyrrolidine were stirred in 20 parts of ethanol. Lower 40-70 ℃ 30 minutes 75 ± 3 ℃ 1
Heat for hours. Then, 10 parts of a 50% ethanol aqueous solution and 0.4 parts of caustic soda are added, and the mixture is stirred at 75 ± 2 ° C for 30 minutes. After cooling, the precipitated crystals are separated, washed with a small amount of ethanol and dried. 1.7 parts of a pyrimidine compound having the following structure (c) was obtained as a pale yellow powder.

(Mp198-203 ° C.) Example 3 2.2 parts of benzo-2-imino-3-cyano-coumarin (formula (a)) described in Example 1, 4-N, N-diethylamino-
2.0 parts of benzaldehyde and 1.2 parts of morpholine are stirred in 20 parts of ethanol with stirring at 40-50 ° C for 30 minutes and at 75-80 ° C for 3 hours. After that, 10 parts of 50% aqueous ethanol solution and caustic soda 0.
Add 4 parts and heat and stir at 75 ± 2 ° C for 30 minutes. Cool down
The precipitated crystals were separated, washed with a small amount of ethanol and dried to obtain 2.1 parts of a pyrimidine compound having the following structure (d). (Mp183-185 ° C) This compound had a light brown color, and when used as a color former in a thermosensitive recording method, it gave a green-blue colored image with excellent light resistance.

Example 4 5.2 parts of 2-hydroxy-1-naphthaldehyde, 3.0 parts of malononitrile and 0.2 part of piperidine in 40 parts of ethanol 40 parts
Stir at ± 2 ° C for 1 hour. Then 4-N-methyl-N-
Add β-chloroethylamino-3-methyl-benzaldehyde (5.9 parts) and piperidine (2.6 parts) at 40-50 ° C for 1 hour 75-
Heat and stir at 80 ° C for 2 hours. Thereafter, 6.0 parts of 28% sodium methylate is added and the mixture is stirred at 75 ± 3 ° C. for 1 hour. After cooling, the precipitated crystals were separated, washed with a small amount of ethanol and dried to obtain 6.8 parts of a pyrimidine compound having the following structure (e). (Mp182-186 ℃) When this compound was used as a color former in a pressure sensitive recording method, a blue recorded image having good light resistance was obtained.

Examples 5 to 16 According to Examples 1 to 4, benz-imino-cyano-coumarin is condensed with benzaldehydes of formula (II) and secondary amines of formula (III) to condense pyrimidine compounds of formula (I). The compound was obtained.

Application Example 1 25 parts of the compound of the formula (b) described in Example 1 and 25 parts of 10% aqueous polyvinyl alcohol solution were mixed with 50 parts of water in a ball mill for 24 hours.
On the other hand, bisphenol A 30 parts, 1
30 parts of 0% polyvinyl alcohol aqueous solution and 40 parts of water are pulverized in a ball mill for 24 hours to obtain a color developer.

15 parts of the coloring liquid and 85 parts of the developing liquid were mixed and evenly coated on high-quality paper so that the dry weight would increase by 10%, and dried to obtain a thermal paper.

This heat-sensitive paper obtained a dark red colored image by heating with a thermal head and endured. The water resistance of the colored image was excellent.

Application Example 2 3 parts of the compound of the formula (c) described in Example 2 is dissolved in 100 parts of KMC-113 (Kureha Chemical Co., Ltd., diisopropylnaphthalene) by heating. On the other hand, 20 parts of gelatin, arabic rubber
Add 12 parts to 200 parts of water and heat to dissolve. The above KMC-113 solution was added with vigorous stirring, and the mixture was stirred for another 3 hours to give an emulsion.

To this, 700 parts of water was added, acetic acid was added to bring about coacervation adjusted to pH = 4, and the mixture was cooled to gel, 50 parts of 30% formalin solution was added, and then caustic soda solution was added to pH. = 9 and heated to 40-50 ° C to harden the capsule film to obtain a coloring solution. The color-developing liquid thus obtained was uniformly applied to high-quality paper so that the weight increase upon drying was 10%, and dried to obtain a color-developing paper. On the other hand, 25% of sodium salt of vinyl acetate / maleic anhydride copolymer in 200 parts of water
Add 50 parts aqueous solution, then 20 parts zinc oxide, 60 kaolin
Parts, 10 parts of titanium oxide and 100 parts of zinc orthophenyl salicylate mud (10% dispersion) were added and dispersed, and further 10 parts of styrene-butadiene latex was added to disperse to obtain a color developer. This color developing solution was uniformly applied to a high-quality paper so that the increase in dry weight was 10%, and dried to obtain a colored paper.

When the two were superposed and the microcapsules were destroyed by pressure, they immediately developed a blue color, giving a light-resistant and excellent colored image.

Application Example 3 2 parts of the compound of the formula (c) described in Example 2 and 2 parts of tetrabutylammonium tosylate as a supporting electrolyte were added to DMF40.
It was melted in a part, and a part of this was filled in an empty cell shown in FIG. 1 to obtain a current-carrying display device. Sweeping was performed while applying voltage by the potential regulation method shown in FIG. Lower electrode 6 of electrification display device
When a positive voltage was applied to the upper electrode by grounding, a deep blue color appeared near the upper electrode at around + 2.2V. When the voltage was swept in the opposite direction, the surface disappeared and became pale yellow near -1.8V. The coloring and erasing period was about 0.7 seconds.

EFFECTS OF THE INVENTION A pyrimidine-based compound which gives a heat-sensitive and pressure-sensitive recorded image having excellent water resistance and light resistance, and gives a current-carrying display with a fast response speed was obtained.

[Brief description of drawings]

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

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B41M 5/30 C09B 11/02 7306-4H

Claims (1)

[Claims] 1. A formula (I) (However, in the formula, R ₁ and R ₂ are hydrogen, chlorine, a methoxy group, an ethoxy group, a methyl group or R ₃ and R ₄ are a methyl group, an ethyl group, a cyanoethyl group,
A β-chloroethyl group or an alkoxyalkyl group having 3 to 4 carbon atoms is shown. X also _{- (CH 2) 4 -,} - (CH 2) 5 - or -
C ₂ H ₄ OC ₂ H ₄ −).