JPH0458475B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to novel xanthene compounds. More specifically, the general formula () (In the formula, R ₁ , R ₂ , R ₃ and R ₄ each represent an alkyl group, a cycloalkyl group or an aryl group, and the aryl group may be substituted with a halogen atom or a lower alkyl group, or an alkyl group may be combined to form a ring. R ₅ to _{R 10} represent a hydrogen atom, an alkyl group, a halogen atom, an alkoxy group, an amino group, an alkylamino group, or an arylamino group, and adjacent R's may be fused to form a ring. The present invention relates to a new xanthene compound represented by (which may form a ring). Conventionally, general formula () Various compounds are known among fluorans having the basic skeleton of , which are acidic and develop colors in various hues, and these compounds are mainly useful for recording materials such as pressure-sensitive recording paper, heat-sensitive recording paper, or photochromic recording materials. Various studies have been carried out as follows. However, such a coloring reaction caused by contact between a fluoran compound and an organic or inorganic acidic substance is a reversible equilibrium reaction, and decolorization can easily occur due to the presence of a substance or conditions that move the fluorine. , phenomena such as decoloring of copied characters occurred, and major problems remained in the reliability of colored images, and improvements were strongly desired. Taking pressure-sensitive recording paper as an example, colored images are easily erased by contact with water or polar solvents such as plasticizers, animal and vegetable oils, and even by increasing the temperature. Reversible decolorization occurs. The present inventors have proposed Japanese Patent Application Laid-open Nos. 57-107882 and 58-172787 to overcome these problems.
No. 57-14273, etc., proposed recording materials based on a new redox coloring system, but the new xanthene compound of the present invention is extremely useful as a chromogen for use in these recording materials. It is. That is, the novel xanthene compound of the present invention, for example, upon contact with a penzoquinone derivative substituted with an electron-absorbing group, causes an irreversible coloring reaction estimated as follows, The color-forming substance () obtained in this way has the carboxyl group on the phenyl group substituted with an amide group that does not have hydrogen, so it no longer undergoes ring closure to the fluorane type and exists as a stable colored substance. Therefore, it has extremely good stability against water, animal and vegetable oils, plasticizers, etc. Therefore, the compounds of the present invention can be used in applications where colored images are formed on a support or in a matrix by energy such as light, heat, or pressure, such as pressure-sensitive recording paper, heat-sensitive recording paper, and free radical photography. It is extremely useful as a chromogen for recording paper (for example, photosensitive resist for printed circuit boards) using The compound of the present invention is synthesized by reduction and amidation of a fluoran compound as follows. For reduction of fluoran compounds, it is convenient to use a strong acid and a metal. For example, a combination of hydrochloric acid and zinc powder, hydrochloric acid and tin, or sulfuric acid and iron powder is used, but the method using zinc powder and hydrochloric acid is the most convenient. It is simple and frequently used. The obtained leuco compound () is dried and treated with a suitable chlorinating reagent such as phosphorus pentachloride, phosphorus trichloride,
After treatment with thionyl chloride or phosphorus oxychloride in an inert solvent, the compound is then reacted with a suitable amine to obtain the desired compound (). Fluoran compound () used to obtain the novel xanthene compound () of the present invention
Specifically, 3,6-bisdimethylaminofluorane, 3-dimethylamino-5,6-benzofluorane, 3-dimethylamino-7,8-
Benzofluorane, 3-diethylamino-6,7
-dimethylfluorane, 3-diethylamino-6
-chloro-7-methylfluorane, 3-diethylamino-6-methoxy-7-amino-fluorane, 3-diethylamino-7-dibenzylaminofluorane, 3-dimethylamino-6-methyl-
7-anilinofluorane, 3-diethylamino-
7-(2'-chlorophenyl)aminofluorane,
3-diethylamino-7-methylbenzylaminofluorane, 3-N-pyrrolidino-6-methyl-
7-anilinofluorane, 3-methyl-cyclohexylamino-6-methyl-7-anilinofluorane, 3-N ethyl-N-P-tolylamino-6
-Methyl-7-anilinofluorane, 3-di-n
Various compounds such as -butylamino-7-(2'-chlorophenyl)amino-fluoran and 3-N-piperidino-6-methyl-7-(4'-methylphenyl)amino-fluoran are exemplified. The amines to be reacted with the above compound () include dimethylamine, diethylamine, methylethylamine, dibutylamine, pyrrolidine, piperidine, morpholine, N-methylaniline, N-ethylaniline, N-methyltoluidine, N-methyloxy Examples include amines such as lysine, N-methylchloroaniline, N-methylanisidine, dibenzylamine, methylbenzylamine, methylcyclohexylamine, N-cyclohexylaniline, and diphenylamine. The xanthene compound of general formula () of the present invention is generally a white solid and stable compound that is soluble in ordinary organic solvents. It quickly develops a color upon contact with a hydrogen-abstracting oxidizing agent or in the presence of an appropriate halogen radical generator and ultraviolet light. Hereinafter, the present invention will be explained in detail with reference to Examples. In the examples, parts indicate parts by weight. Example 1 15 parts of 3-diethylamino-6-chloro-7-methylfluorane were mixed with 50 parts of glacial acetic acid and dissolved by heating. 15 parts of concentrated hydrochloric acid was added, and then 10 parts of zinc powder was added little by little over 20 minutes while stirring at 60-70°C, and the contents were gradually decolorized while generating reaction heat. Further, while stirring, 5 parts of concentrated hydrochloric acid was added and the mixture was boiled for 15 minutes to completely decolorize it. The contents were heated, and the mass was mixed with a small amount of glacial acetic acid-hydrochloric acid (3:
1) Dyeing with the mixture. When the liquid was drained into a large amount of ice water, the reduced product, 3-diethylamino-6-chloro-7-methyl-9-(2'-carboxy)phenylxanthene, precipitated as a candy-like substance, and was further stirred to form a solid. Obtained the object. The obtained solid was filtered, washed with water, then mixed with 200 parts of boiling water, and the system was made slightly alkaline with sodium carbonate while stirring, filtered,
Washed with water and dried. 10 parts of this dry reduced product was mixed with 5 parts of phosphorus pentachloride in 50 parts of xylene, mixed and boiled for 30 minutes, then 5 parts of monomethylaniline was added, and the mixture was reacted under heating under reflux for about 2 hours. Furthermore, 10 parts of anhydrous sodium carbonate was added, and water was carefully added to neutralize the contents. After confirming that the contents are alkaline, xylene and excess monomethylaniline are distilled off by steam distillation. The product was filtered and dried, extracted with xylene, the xylene solution was concentrated, ligroin was added until it became cloudy, and the mixture was stored at 0° C. or below, resulting in the precipitation of white crystals. The crystals were filtered and recrystallized from xylene-ligroin to give 3-diethylamino-6-chloro-
White crystals of 7-methyl-9-(2-methylphenylcarboxamide) phenylxanthene were obtained in a yield of 50%. Melting point 115-117℃. The elemental analysis values were as follows.Elemental analysis value (%) C H N Cl Calculated value 74.61 6.27 5.61 7.10 Actual value 75.23 5.62 5.48 7.69 Example 2 3-dibutylamino-7 was prepared in the same manner as in Example 1.
-(2″-Chloro-phenyl)amino-fluorane was reductively amidated in the same manner as in Example 1 to obtain a melting point of 182-
White crystals at 183°C were obtained. The elemental analysis values of the obtained compound were as follows. Elemental analysis value (%) C H N Cl Calculated value 76.44 6.57 6.52 5.50 Actual value 76.23 6.31 6.49 5.63 The nuclear magnetic resonance spectrum of this substance is 3.5 ppm

[Formula] Hydrogen for 3 atoms of the methyl group in the structure, and - of the -CH group of the xanthene nucleus at 5.3 ppm
Atomic hydrogen, 0.8-3.3ppm of n-butyl group 18
The absorption spectrum of atomic hydrogen was confirmed. Furthermore, according to the mass spectrum of this material, m/z
The parent ion peak (molecular weight of C ¹² , Cl ³⁵ isotope) is at =643 and the peak is at m/z = 536.

A separated peak of [Formula] was observed. Example 3-14 The compounds shown in Table 1 below were synthesized in the same manner as in Examples 1 and 2, and their elemental analysis values all agreed well with the calculated values.

【table】

[Table] Reference Example 1 Pressure-sensitive copying paper using the xanthene chromogen of this example was obtained in Example 2. 3-di-n-butylamino-
Phenylxylylethane in which 3% by weight of 7-(2″-chlorophenyl)amino-9-(2′methylphenylcarboxamide)phenylxanthene was dissolved.
In 200 parts of a 3% aqueous solution of ethylene maleic anhydride copolymer adjusted to pH 4.5, an average particle size of 3μ is added.
Emulsify and disperse until In-
Microcapsules with melamine formaldehyde resin film were obtained by in-situ method. A mixture of 50 parts of this microcapsule liquid, 8 parts of wheat flour starch particles (average particle size 18μ), and 3 parts of a 20% boiled starch aqueous solution was spread on high-quality paper so that the dry coating amount was 5 g/m ² . The coating was applied with a Meyer bar and dried to obtain a top sheet for pressure-sensitive copying paper. Separately prepared 2,5-diethoxycarbonyl-3,6-di-p
- Base paper for pressure-sensitive copying paper containing tolylsulfonyl-1,4-benzoquinone as a color developer (coating amount: 5 g/m ²
When the surface was pressed against the coated surface (dry solid composition: 85% calcium carbonate, 6% SBR latex, 6% boiled starch binder, 3% developer) and was pressed with a typewriter, a deep green colored image was obtained. Obtained. This colored image did not fade quickly even on contact with polar solvents and had excellent light resistance. Reference Example 2 Thermal recording paper using the xanthene derivative of the present invention 10 parts of 3-diethylamino-6-chloro-7-methyl-9-(2'-methylphenylcarboxamide)-phenylxanthene obtained in Example 1, The mixture was atomized in a sand grinding mill with 20 parts of a 10% polyvinyl alcohol aqueous solution (Kuraray, Poval #117) and 20 parts of water to obtain a chromogen dispersion (liquid A). Separately, 10 g of 2,5-dibenzoyl-1,4-benzoquinone was atomized with the same composition as the above dye to obtain a color developer and a dispersion (liquid B). Mix A liquid, B liquid, and the separately dispersion-treated components to create an aqueous coating liquid with the following composition: Weight composition (dry) Color source 2 Color developer 5 Stearic acid amide 5 Zinc stearate 5 Calcium carbonate 63 Polyvinyl alcohol 20 total 100 The dry coating amount of the water-based paint on high-quality paper is 6 g/m ²
It was coated and dried to obtain heat-sensitive recording paper. This thermosensitive recording paper was colored using a thick film printer thermal head with a resistance value of 100 ohms under voltage application conditions of an applied voltage of 20 V and a pulse width of 1.4 milliseconds to obtain a red colored image. This colored image is stable,
No discoloration occurred even when it came into contact with fats and oils or plasticizers. Reference Example 3 Example of dry film resist for printed circuit formation using the xanthene chromogen of the present invention (1) 100 parts by weight of acrylic resin containing 50% toluene (trade name Almatex L-1044...manufactured by Mitsui Toatsu Chemicals) (2) Compound represented by the following formula 50 parts by weight (Product name BP4EA...manufactured by Kyoeisha Yushi) (3) Photosensitizer (A) 2-Hydroxy-2-methylpropiophenone (Product name Darokyure 1173...manufactured by Merck & Co., Ltd.)
1 part by weight (B) 2 parts by weight of P-phenoxy-2,2-dichloroacetophenone (4) 3-diethylamino-6-methyl-7-anilino-9-(2'-ethyl phenylcarboxamide) phenyl-xanthene, 1
Part by weight and 50 g of toluene were mixed and dissolved in a room protected from ultraviolet rays to form a colorless and transparent solution. It was applied onto a 25μ thick polyester film using a bar coater and then dried for 10 minutes in a dryer at 130°C. After drying, it was adhered to a 15μ thick polyethylene film (protective layer) according to a conventional method to create a three-layer dry film resist. At this point, the photoresist layer was clear and colorless. While peeling off the dry film protective layer, the dry film was heated and laminated onto the clean copper surface of a glass cloth epoxy copper clad laminate, and then cooled to room temperature. A silver salt photomask was placed on the top and exposed using an ultra-high pressure mercury lamp (manufactured by Oak Seisakusho, 3KW x 1 lamp) under the exposure conditions of 200mj x 15sec.The transparent part of the photomask was colored and hardened to a dark green color. The opaque areas remained uncured and uncolored, and the patterns in the exposed and unexposed areas were very clear. Do this according to the usual method,
When spraying with 1,1,1-trichloroethane, the unexposed areas were completely removed, the copper surface was exposed, and a dark green pattern remained in the exposed and hardened areas.

Claims (1)

[Claims] 1 General formula () (In the formula, R ₁ , R ₂ , R ₃ and R ₄ each represent an alkyl group, a cycloalkyl group or an aryl group, and the aryl group may be substituted with a halogen atom or a lower alkyl group, or an alkyl group may be combined to form a ring. R ₅ to _{R 10} represent a hydrogen atom, an alkyl group, a halogen atom, an alkoxy group, an amino group, or an alkylamino group, and adjacent R's may be fused to form a ring. A new xanthene compound represented by