WO2005121072A1 - Hydroxyphenylhydroxy- alkylamides, reversible thermo- sensitive compositions and reversible thermal printing materials containing them, and color developing and reducing process with the same - Google Patents

Abstract

The invention provides novel hydroxyphenylhydroxy- alkylamides; reversible thermosensitive compositions and reversible thermal printing materials which contain the amides and are excellent in stability of color development, erasability, sensitivity of color development, the balance between color developing temperature and erasing temperature, and thermal stability of the colored state in storage; and a color developing and reducing process with the amides, more specifically, hydroxyphenylhydroxyalkylamides represented by the general formula (I); and reversible thermosensitive compositions and reversible thermal printing materials which each contain both an electron-accepting compound as described above and an electron-donating color-forming compound: (I) (wherein n is an integer of 1 to 3; and A is straight-chain hydroxyalkyl having a hydroxyl group on a non-terminal carbon atom). The printing materials can cause color development or erasing by temperature control.

Description

 Specification

 Hydroxyphenylhydroxyalkylamide compound, reversible thermosensitive composition using the same, reversible thermosensitive recording material, and color erasing process

 Technical field

 The present invention relates to a novel hydroxyfluorohydroxyalkylamide compound which can be used for heat-sensitive recording (color development / decoloration / decolorization), a recording material reversible thermosensitive composition using the same, and a recording medium. It concerns the decoloring process.

 Background art

 [0002] It is well known that a colorless or light-colored electron-donating color-forming compound reacts with an electron-accepting compound to form an irreversible color. Recording papers utilizing this principle include pressure-sensitive paper and heat-sensitive paper.For pressure-sensitive paper, a leuco dye solution, which is an electron-donating coloring compound, is encapsulated in microcapsules and coated with a binder and the like. Microcapsules are broken by external pressure by using a base paper coated with an electron accepting conjugate such as bisphenol A together with a binder, and the electron donating compound and the electron accepting compound are combined. There is a method utilizing a melting reaction with a sex dangling product to produce a color.

 [0003] Further, as the thermal paper, a paper coated with a fine powder of a leuco dye, bisphenol A, a sensitizer, a storage stabilizer and the like together with a binder is also known. This thermal paper utilizes coloration by heat supplied from the head of a thermal printer (for example, see Patent Document 1).

 [0004] Conventionally, from the viewpoint of reducing the environmental load or from the viewpoint of convenience, technology has been energetically developed to thermally and reversibly perform coloring and decoloring. For example, a thermochromic composition using a leuco dye, which is an electron-donating coloring compound, and a phenol, which is an electron-accepting compound, is described in Patent Document 2, for example. .

[0005] In addition, (a) an electron-donating color-forming compound, (b) an electron-accepting compound, and (c) a reaction temperature regulator, a color is selected by the component (a), Patent Documents 3-5, etc. disclose reversible thermochromic compositions and compositions containing this composition in microcapsules, in which the color density is selected by component (b) and the coloration temperature is determined by component (c). Has been described. Patent Documents 6 to 9 disclose electric children. A recording layer composed of an electron-accepting compound such as a color-forming compound, gallic acid or phloroglucinol and a binder such as cellulose acetate is provided on a substrate, an image is formed with heat, and an image is formed with water or water vapor. An erasable reversible recording material is disclosed.

 [0006] However, these recording materials erase an image with water or water vapor, and thus have a problem in image stability that the formed image is easily affected by moisture or moisture.

 [0007] Patent Document 10 discloses a biphasic solution comprising a compound having a rataton ring as an electron-donating color conjugate and an alkylphenol which is liquid at room temperature as an electron-accepting conjugate. There is disclosed a material which is used by encapsulating it in glass or microcapsules without using a binder, and which reversibly develops decoloration and color by heating and cooling. The material described in this patent document is colorless and transparent when heated, and loses its fluidity when cooled to develop color. However, since there is no hysteresis, it is not possible to retain records, and there is room for improvement as a recording material.

 [0008] Further, there has been proposed a reversible thermosensitive recording material comprising a leuco dye, an amphoteric conjugate having a functional group capable of forming or decoloring by reacting with the dye, and a polymer binder. It is disclosed in Patent Documents 11 to 21 and the like. More specifically, Patent Literature 11 discloses a complex of gallic acid and 3-methoxypropylamine, which is an amphoteric conjugate having a functional group relating to color development or decoloration, crystal violet lactone and polybutyl alcohol binder. A heat-sensitive recording material comprising: Patent Document 16 discloses a heat-sensitive recording material comprising a compound having at least one of a phenolic hydroxyl group or a carboxyl group and having an amino group as a functional group, and a binder of talristal bioretactone and a methacrylic resin. ing.

 [0009] However, these reversible thermosensitive recording materials are difficult to control the temperature of color development and decoloration due to competitive color development and decoloration, and have poor image contrast. However, there is a problem that the material is degraded due to the decoloring, and the number of times of repeated use is reduced.

[0010] Patent Document 22 discloses an electron-donating color-forming compound, a phosphonic acid conjugate having a long-chain aliphatic hydrocarbon group, an aliphatic carboxylic acid compound, and a phenolic conjugate. Coloration and quenching by the combination of an electron-donating compound and an electron-donating color-forming compound. By controlling the heating and cooling of colors, recording materials can be easily made, and recording materials that stably maintain the colors at room temperature have been proposed. When the composition is heated to the color development temperature range, the two conjugates are melted and reacted to form a ring, thereby opening the color and forming a color. It is said that the state can be maintained. Then, when the colored composition is heated to a decolorizing temperature range lower than the color development temperature range, the long-chain alkyl groups of the electron-accepting compound aggregate, and the electron-accepting compound becomes a single crystal, and the color forming body is formed. It is presumed that the color is separated from the color, and as a result, the color is erased. That is, in the relationship between the electron-donating color-forming compound and the electron-accepting compound, the compound is solidified while being kept in a reacted state, so that the color-developed state is maintained, It is stated that the receptive compound crystallizes and separates under thermal conditions, forming a single crystal and maintaining a bleached state. While these recording materials were used, the phenolic conjugates described in the examples were at practical levels in terms of density and stability of color development, except for those parts having disadvantages of poor color erasability. However, as described in Non-Patent Document 1, there is a problem that the decoloring speed takes a long time.

On the other hand, Patent Document 23 proposes a recording material capable of repeating printing and erasing in the same manner.By using a special phenolic conjugate as an electron-accepting conjugate, the erasing speed is improved, It is shown that the print image can be almost erased by heating within one second. However, as described in Non-Patent Document 2, the storage stability of this material is not always sufficient at temperatures exceeding 30 ° C, so it is necessary to further improve the storage stability in practical use. desired. In addition, Non-Patent Document 1 described above discloses, as a means for solving these problems (storage stability, erasing speed, or coloring / erasing density), hydrogen bonding in a molecule and acidity of an electron-accepting compound. Focusing on the degree, the hydrogen bonding property is effectively improved by introducing a hydrogen-bonding functional group into the long-chain alkyl group of the electron-accepting compound and introducing a methylene chain as a spacer. Investigation results of materials that can be expressed and have good storage stability have been reported. Although the storage stability is improved by using this electron-accepting conjugate, the introduction of a functional group and a spacer increases the melting point by about 20-50 ° C. as compared to before the introduction. . This melting point is correlated with the color-forming temperature, that is, with the color-forming sensitivity, and as a result, the color-forming sensitivity tends to decrease. The decrease in color sensitivity is due to the fact that fax, Or, in the case of a thermal head such as a thermal printer, it means that the color density becomes low, and it is difficult to use it as it is with existing hardware. As a result, issues remain, such as the need to use dedicated hardware or use other additives such as sensitizers to increase sensitivity.

Patent Document 1: Japanese Patent Publication No. 4-7600

Patent Document 2: US Pat. No. 3,560,229

Patent Document 3: Japanese Patent Publication No. 51-44706

Patent Document 4: Japanese Patent Publication No. 51 44707

Patent Document 5: Japanese Patent Publication No. 51-44708

Patent Document 6: JP-A-58-191190

Patent Document 7: JP-A-60-257289

Patent Document 8: Japanese Patent Publication No. Hei 4 30355

Patent Document 9: Japanese Patent Publication No. 4 30916

Patent Document 10: JP-A-63-315287

Patent Document 11: JP-A-5-254244

Patent Document 12: JP-A-5-262032

Patent Document 13: JP-A-6-48028

Patent Document 14: JP-A-2-188293

Patent Document 15: JP-A-2-188294

Patent Document 16: International Patent Publication No. WO90Z11898 pamphlet

Patent Document 17: JP-A-4-46986

Patent Document 18: JP-A-4-303680

Patent Document 19: JP-A-4-50289

Patent Document 20: JP-A-4-50290

Patent Document 21: JP-A-5-177931

Patent Document 22: Patent No. 2981558

Patent Document 23: Japanese Patent No. 3380277

Non-patent Document 1: Ricoh Technical Report 25, 6 (1999) Non-Patent Document 2: Proceedings of the 3rd Technical Meeting of the Society of Electrophotography 1997, 10 (1997) Disclosure of Invention

 Problems to be solved by the invention

[0012] In view of the above problems, it is an object of the present invention to maintain color stability and erasability, and to have good storage stability against heat in a colored state without lowering the color sensitivity or high-speed erasability. An object of the present invention is to provide an electron-accepting compound which can be applied to a reversible thermosensitive recording material, and to provide a reversible thermosensitive recording material using the same and a coloring / erasing process. Means for solving the problem

[0013] The hydroxyphenylhydroxyalkylamido conjugate according to the present invention is characterized by being represented by the following general formula (I).

[Chemical 1]

(Here, n is an integer of 13 and A is a straight-chain hydroxyalkyl group having a hydroxyl group bonded to a carbon atom other than the terminal carbon.)

[0014] Further, the reversible thermosensitive composition according to the present invention comprises a hydroxyphenylhydroxyalkylamidide compound represented by the general formula (I) and an electron-donating color-forming compound. It is a feature.

 [0015] Further, the reversible thermosensitive recording material according to the present invention is a recording material comprising a hydroxyphenylhydroxyalkylamide conjugate represented by the general formula (I) and an electron donating coloration conjugate. It is characterized by comprising an element.

[0016] Further, the color developing / erasing process according to the present invention comprises a recording element containing a hydroxyphenyl hydroxyalkylamide compound represented by the general formula (I) and an electron-donating color-forming compound. The reversible thermosensitive recording material is heated to a color development temperature at which both the electron-accepting compound and the electron-donating color-forming compound melt, and then rapidly cooled to stably maintain a color-developed state. The melting temperature is lower than the coloring temperature. It is characterized in that it is decolorized by heating to the decolorization temperature range where the reaction and the reverse reaction occur.

 The invention's effect

 According to the present invention, a reversible thermosensitive recording material having excellent color stability and erasability, color sensitivity, a balance between a color developing temperature and a color erasing temperature, and excellent storage stability against heat in a color developing state is realized. There is provided a hydroxyphenylhydroxyalkylamide compound, which is a possible electron accepting compound. The hydroxyphenylhydroxyalkylamide compound is suitable for a reversible thermosensitive recording material, and can also realize a reversible thermosensitive composition, a reversible thermosensitive recording material, and a coloring / decoloring process having the above-mentioned characteristics. It is.

 Brief Description of Drawings

FIG. 1 is a conceptual diagram of coloring or decoloring in the reversible thermosensitive composition of the present invention.

 [FIG. 2] IR ^ vector of N- (4-hydroxyphenyl) -12-hydroxystearamide synthesized in Synthesis Example 1!

 FIG. 3 is a DSC chart of N- (4-hydroxyphenyl) -12-hydroxystearamide synthesized in Synthesis Example 1!

 [FIG. 4] IR ^ vector of N- (3-hydroxyphenyl) -12-hydroxystearamide synthesized in Synthesis Example 2.

 FIG. 5 is a DSC chart of N- (3-hydroxyphenyl) -12-hydroxystearamide synthesized in Synthesis Example 2.

 [FIG. 6] IR spectrum of N- (4-hydroxyphenyl) -12-hydroxypentadecaneamide synthesized in Synthesis Example 3!

 FIG. 7 is a DSC chart of N- (4-hydroxyphenyl) -12-hydroxypentadecaneamide synthesized in Synthesis Example 3.

 BEST MODE FOR CARRYING OUT THE INVENTION

[0019] 1. Hydroxyphenyl hydroxyalkylamide compound

The present inventor has found that a functional group capable of forming a hydrogen bond, specifically a hydroxyl group, is not bonded to a terminal carbon in an alkyl chain of an amide group-containing phenolic compound having a long-chain alkyl group. By substituting a hydrogen atom and expressing hydrogen bonding ability, It has been found that when used as a reversible heat-sensitive material that does not significantly change the melting point of the xylphenol-hydroxyalkylamido conjugate, the erasing performance is not impaired, and the coloring stability and coloring sensitivity can be unexpectedly improved. Was.

 The hydroxyphenylhydroxyalkylamido conjugate according to the present invention is represented by the following general formula (I).

[Chemical 2]

Here, n is an integer of 13 and A is a straight-chain hydroxyalkyl group having a hydroxyl group bonded to a carbon atom other than the terminal carbon.

This hydroxyphenylhydroxyalkylamide compound can be used as an electron-accepting compound that can be used in a heat-sensitive recording material in combination with an electron-donating color-forming compound. For this reason, the hydroxyphenylhydroxyalkylamide compound according to the present invention may be hereinafter referred to as an electron-accepting compound.

Specific examples of the structural formula of A include those represented by the following general formula (Π).

[Formula 3]

Here, m and 1 are each independently an integer of 0 or more, and k represents an integer of 1 or more.

[0023] When m + 1 increases, aggregation of alkyl chains tends to occur easily when used in a reversible thermosensitive recording material, and erasability tends to improve. Therefore, m + 1 is preferably 6 or more. More preferably, it is 11 or more. On the other hand, when the value of m + 1 decreases, the melting point of the compound tends to decrease and the color sensitivity tends to improve. Therefore, the value of m + 1 is preferably 22 or less.

[0024] Further, k is preferably 1 or 2 from the viewpoint of the erasability of an image and the stability of coloring when used in a reversible thermosensitive recording material.

Specific examples of such compounds include the following compounds.

[0026] The compound represented by the general formula (I) can be synthesized by using an commonly known amide synthesis method. More specifically, an aminophenol having 13 hydroxyl groups and a hydroxyalkylcarboxylic acid having a hydroxyl group bonded to a carbon other than the terminal carbon are optionally combined with a solvent and Z or a catalyst in the presence of a solvent. It can be produced by heating to reflux. One of the features is that these electron accepting conjugates can be synthesized using general-purpose chemicals.

[0027] Whether or not the target compound has been obtained is determined by differential scanning calorimetry (hereinafter referred to as DSC). And IR absorption spectrum (hereinafter sometimes referred to as IR).

[0028] 2. Reversible thermosensitive composition

 The reversible thermosensitive composition according to the present invention comprises the hydroxyphenylhydroxyalkylamide compound represented by the general formula (I) and an electron-donating color former. This composition shows a reversible color change by temperature control. This composition can also be used as an irreversible thermochromic composition.

FIG. 1 shows a conceptual diagram of color development or decoloration by a combination (that is, a mixture) of an electron-accepting compound and an electron-donating color-forming compound in the reversible thermosensitive composition according to the present invention. is there.

 In FIG. 1, the decolored state A is a state in which the two conjugates have not reacted in the mixture.

 When this mixture is heated and reaches D (the temperature near or above D is called the color temperature range, which is the temperature near the melting point of the electron-accepting compound) via B and C, the electron-accepting compound is heated. The product and the electron-donating color-forming compound react in a melt-mixed state and develop color. When this is quenched, the electron-accepting compound and the electron-donating color-forming compound are solidified in a reacted state, so that the path from the decolored state A to the colored state D is a different path. The color development state is maintained at a low temperature, for example, at room temperature. Next, when heated to a temperature between the E state force B and the temperature in the vicinity (the temperature range near this is called the decolorization temperature range), the electron accepting compound alone causes aggregation of the alkyl chain, and the electron donating color forming compound Is broken and the color is erased. Even if this is cooled to room temperature, it does not change to the color developing state E and is kept in the decoloring state A. As described above, the use of the electron-accepting conjugate of the present invention can maintain any state of color development and decoloration at a low temperature.

[0031] The electron-accepting conjugate that can be used in the present invention is limited to those described in the general formula (I), but the electron-donating color compound combined therewith is not particularly limited. One example of an electron-donating color-forming compound is a colorless or pale-colored dye used as a pressure-sensitive thermosensitive dye, which is generally called a leuco dye, and includes triphenylmethanephthalide dyes, fluoran dyes, Drillphthalide dyes, spiropyran dyes, rhodamine lactam dyes, trifluorophenolic dyes, azaphthalide dyes, azomethine dyes, And phenothiazine dyes. Specific examples of the electron-donating color-forming compound that can be used in the present invention will be shown below, but it should not be construed that the invention is limited thereto.

3-Getylamino-6-methyl-7-phenylaminofluoran, 3-Getylamino-7- (2-chlorophenol) aminofluoran, 3-Getylamino-7- (2-bromophenyl) aminofluorane, 3-Gethylamino 6-methyl-7-chloro fluoran, 3-methylethyl 6-methyl-7- (3-trifluoromethylphenyl) aminofluoran, 3-methylethylamino 7-chlorofluorin, 3-methylethylamino 7-bromofluoran, 3—Jetylamino 1 7—Piperidinofluoran, 3—Jetylamino-7— (N—ethylethyl N-phenyl) aminofluoran, 3—Jethylamino 7,8—Venzofluoran, 3—Jetylamino 1 6—Black mouth 1 7 — (2,3-Dicyclohexylphenol) amino fluoran, 3—Jethylamino 6 -Laminofluoran, 3-Jethylamino-6-methyl-7-(2,4-dimethylphenyl) aminofluoran, 3-Jethylamino-6-chloro mouth-7-(3-trifluoromethylphenyl) aminofluoran, 3-Gethylamino-6-methyl-7-phenylaminofluoran, 3-diethylamino-7- (3-trifluoromethylphenyl) aminofluoran, 3-dipropylamino-7-chlorofluorinated, 3-ethylamino 6-methyl-7- (3-trichloromethylphenyl) aminofluoran, 3-methylethylamino-7- (2-methoxycarbylphenol) aminofluoran, 3-diarylamino 7,8-benzofluoran, 3-ethylamino 7- (N-a-phenethyl) aminofluoran, 3-getylamino-5-methyl-7- (N-phenyl Tyl) aminofluoran, 3-getylamino-5-methyl-7-dibenzylaminofluoran, 3-getylamino-7-medoxyfluoran, 3-getylamino-6-dimethylaminofluoran, 3-getylaminofluoran-7- (p-toluidino) fluoran, 3 —Jetylamino 1-5—Chloro 7— {N—Benzyl N— (Trifluoromethylphenyl)} aminofluorane, 3-dibutylamino— 7— (2Chloromethyl) aminofluoran, 3-Jetylamino— 7-acetaminofluoran, 3-dibutylamino-6-chloro-7-ethoxyxylaminofluoran, 3 dibutylamino-7- (2fluorophenyl) aminofluoran, 3 dibutylamino 7,8-benzofluoran , 3-cyclohexylamino-6-chloro fluoran, 3-dibutylamine Over 6-methyl-7-phenylalanine § amino fluoran, 3-dimethylamino -5, 7-dimethyl fluoran, 3- cycloheteroalkyl Kishiruamino one 6- black port fluoran, Kishiruamino one to 3-cyclopropyl 6-Bromofluorane, 3-cyclohexylamino-6-chloro-7- (2-chlorophenol) aminofluoran, 3- (N-methyl-N-cyclohexyl) amino-7,8-benzofur Oran, 3- (N-ethyl-N-n-octyl) amino-7,8-benzofluoran, 3- (N-ethyl-N-ioamyl) amino-7,8-benzofluoran, 3- (N-ethyl-N — I-Amyl) amino-7-chlorofluorane, 3- (N-methyl-N-cyclohexyl) amino— 6-methyl-7— (3-trifluoromethylphenyl) aminofluorane, 3 -— (N-methyl-N-i-propyl) Amino-6-methyl-7-phenylaminofluoran, 3- (N-benzyl-N-cyclohexyl) amino-5,6-benzo-7- (4-bromonaphthyl) aminofluoran, 3- (N-butyl) N-methyl) a 6-methyl-7-phenylaminofluoran, 3- (N-ethyl-N-i-amyl) amino-6-methyl-7-phenylaminofluoran, 3- (N-ethyl-N-hexyl) amino 7-Fu-aminofluoran, 3- (N-n-amylane N-methyl) amino-6-methyl-7-phen-aminofluoran, 3- (N-methyl-N-cyclohexyl) amino-6-methyl-7-fue -Lumiaminofluoran, 3- (N-methyl-N-n-propyl) amino-6-methyl-7-phenylaminofluoran, 3- (N-n-propylN-i-propyl) amino-6-methyl-7-phenylaminofluoran, 3- (N-ethyl-N-Sec-butyl) amino- 6-methyl-7-phenylaminofluorane, 3- (N-ethyl-N-n-amyl) amino-6-methyl-7-phenylmethylfluoran, 3 G n-octylamino-1 7— (4-black phenol) aminofluoran, 3—n—butyamino— 7— (4-chlorophenol) aminofluoran, 3— (N—n—butylN— n —Amyl) amino-7— (4-acetylfuryl) amino fluoran, 3-n-octylamino-1 7— (4-chlorophenyl) aminofluoran, 3-n cetylamino-7— (4-chlorophenol) aminofluoran, 3 —Pyrrolidino 6-methyl 7-phenaminofluorane, 3-pyrrolidino 7— {bis (4-chlorophenol) methyl} aminofluoran, 3-morpholino 7— {N-propyl N— (4—trifluoro L-aminophenyl) 3-aminofluoran, 3-pyrrolidino 6-chloro-7-phenylaminofluoran, 3-pyrrolidino-6-methyl-7- (3-trifluoromethylphenyl) aminofluor 7- {N-Propyl N- (3-trifluorophenol)} aminofluoran, 3- (N-ethyl-N-ethoxyxyl) amino-7,8-Venzofluoran, 3- {N-ethyl- N- (2 ethoxypropyl)} amino-6-methyl-7 phenylaminofluoran, 3- (N-ethyl-N-tetrahydrofurfuryl) amino-6-methyl-7-phenylaminophenyl Luoran, 3- (N-methyl-N-phenyl) amino- 7-aminofluoran, 3- (N-methyl-N-phenyl) amino-7-N-methylaminofluoran, 3- (N-methyl-N-phenyl -Le) amino 7-dimethylaminofluoran, 3- (N-methyl-N-phenyl) amino-7-dipropylaminofluoran, 3- (N-ethyl-N-phenyl) -6-methyl-7- {N —Ethyl-N— (4-methylphenyl)} aminofluoran, 3- (N-ethyl-N-phenyl) amino-7-dimethylaminofluoran, 3- (N-ethyl-N-phenyl) amino-7-dipropylamino Fluoran, 3- (N-ethyl-N-phenyl) amino-7-aminofluoran, 3- (N-phenyl-N-propyl) amino-7-aminofluoran, 3- (N-ethyl-N-phenyl) 1-amino 7- N-methylaminofluoran 3- (N-propyl N-phenyl) amino-7-N-methylaminofluoran, 3- {N-methyl-N— (4-methylphenyl)} amino—5-methoxy-7-dibenzylaminofluoran, 3- {N— Methyl-N- (4-methylphenyl)} amino-6-t-butyl-7- (4-methylphenyl) aminofluoran, 3- {N-methyl-N- (4-methylphenyl)} amino-7- (2-methoxy) Benzoyl) aminofluorane, 3- {N-methyl-N— (4-methylphenyl)} amino-7-acetylaminofluoran, 3- {N-methyl-N— (4-methylphenyl)} amino-7 —Dibenzylaminofluoran, 3— {N-methyl-N— (4-methylphenyl)} amino—7—Getylaminofluoran, 3- {N-methyl-N— (4-methylphenyl) } Amino— 7-ethylaminofluoran, 3- {N-methyl- N— (4-Methylphenyl)} amino—7-aminofluorane, 3- (N-methyl-N-phenyl) amino-6-methyl-7-phenylaminofluorane, 3— (3-trifluoromethyl Phenyl) amino-6-Jetylaminofluoran, 3- {N-ethyl N- (4-methylphenyl)} amino-6-methyl-7-phenylaminofluoran, 3- {N — Ethyl-N— (4-methylphenyl)} amino— 7— (N-methyl-N-phenyl) aminofluoran; 3- {N-ethyl-N— (4-methylphenyl)} amino—7— (α Phenethyl) amino fluoran, 3- {Ν-ethyl Ν— (4-methylphenyl)} amino-7-aminofluoran, 3 — {Νethylethyl Ν— (4-methylphenyl)} amino-7-butyla Minofluoran, 3— {Ν—ethyl-Ν— (4-methylphenol)} amino—7—diben Ziraminofluoran, 3-{{ethylethyl} — (4-methylphenyl)} amino-7— {bis (4-methylbenzyl)} aminofluoran, 3-{{ethylethyl} — (4-methylphenyl) -Le)} amino-7-benzoylaminofluoran, 3- {Ν-ethyl-Ν (4-methylphenyl)} amino-5-methyl-7-dibenzylaminophen Luorane, 3- {N-ethyl-N- (4-methylphenyl)} amino—5-chloro-7-dibenzylaminofluoran, 3- {N-ethyl-N- (4-methylphenyl)} amino-6-methylfluora 3- (N-ethyl-N- (4-methylphenyl)} amino-5-methoxyfluorane, 3- {N-ethyl-N- (4-methylphenyl)} amino-7,8-benzofluoran, 3 — {N-propyl N— (4-methylphenyl)} amino-6-methyl-7— {N-emel N— (4-methylphenyl)} aminofluoran, 3-—N-propyl N— (4-methylphenyl) } Amino 7-aminofluorane, 3- {N-ethyl-N- (4-ethylthiol)} amino-7-aminofluoran, 3- {N-methyl-N- (4-ethylethyl)} amino-7-aminofluoran , 3— {N—Ethyru N— (4 methylphenyl)} amino— 7-Jetylaminofluoran, 3- {N-ethyl-N— (4-ethylfuryl)} amino— 7-aminofluoran, 3- {N-propylN— (4-ethylfuryl)} amino-7 Aminofluoran, 3- {N-methyl-N— (2,4-dimethylphenyl)} amino—7-benzylaminofluoran, 3- {N-ethyl-N— (2,4-dimethylphenyl)} — 7 — Aminofluoran, 3 -— {N-methyl-N— (2,4-dimethylphenyl)} amino-7-methylaminofluoran, 3- {N-ethyl-N— (2,4-dimethylphenyl)} amino-7-ethylaminofluoran , 3- {N-ethyl-N- (2,4-dimethylphenyl)} amino-7-benzylaminofluoran, 3- {N-propylN— (2,4-dimethylphenyl)} amino-7-aminofluoran, 3- {N-Methyl-N— (4-chlorophenol)} Amino-ami Nofluoran, 3— {N—ethyl N— (4-chlorophenol)} amino-1 7-aminofluoran, 3— {N—propyl N— (4-chlorophenyl)} amino-1 7—aminofluoran, 3 —Cyclohexylamino-1 7-bromoaminofluoran, 2,7-dichloro-3-n-butylamino-6-methylfluoran, 3-di-n-butylamino-6,7-butylenefluoran, 3-amino-5-methylfluoran, 2-methyl-3 —Amino 6-methyl-7 Methylfluoran, 1,3,3-Trimethylindolino 6 ′ —Nitrobenzo pyrirospiran, 1,3,3—Trimethinoleindrino 6 ′ —Nitro 8 '-Methoxybenzopyrrolopyran, 1,3,3-trimethinoleindolino 6'Bromobenzopyrrolospirane, 1,3,3-trimethylindolino-methoxybenzopyrrolospirane, 1,3 , 3-Trimethylindolinoben zopyrrolospirane, 1,3,3-trimethinoleindolino j8-naphthopyrrolospirane, 3,3 bis (4-dimethylaminophenol) -6- ヂ methylaminophthalide, 3,3-bis (4-dimethylaminophenol) -6-methylaminophthalide, bis (4-dimethylaminophenol) 2-carboxylate, bis (4-dimethylaminophenol) (4-ethylamino) phenolmethane-2 carboxylate, bis (4-dibutylaminophenyl) phenylmethane2carboxylate, {2 —Hydroxy- (4-ethylpyramino) phenyl}-(2-methoxy-5-methylphenyl) phenylmethane-2 carboxylate, {2-hydroxy— (4 dimethyl

 (Xyamino) phenyl} — (2-hydroxy-5-chlorophenol) phenylmethane 2 carboxylate, (4-dimethylaminophenyl) (2-hydroxy-4-chloro-5-methoxyphenyl) Phenylmethane-2 carboxylate, 3- (4-ethylethyl-2 ethoxyphenyl)-3- (1-ethylmethyl 2 indole-3 yl) 4-azaphthalide, 3-{(4-ethylethylamino-2 ethoxyphenyl) ) —3— (2-Methyl-1 n—Cutylindole-3-yl) 4—azaphthalide, 3,3-bis (2-methyl-1-ethylindol-3-yl) phthalide, 3— (4—Jethylamino — 2-Methoxyphenyl) -3- (2-Methyl-1-ethylindole-3-yl) —phthalide, 3- (4-methylethylamino-2-methylphenyl) — 3 -— (1,2-dimethylindole) 3 yl) —phthalide, 3, 3-bi (2-Methyl-1-octylindole-3-yl) phthalide, rhodamine-linolatatam, rhodamine 2 chloroa-linolatatam, rhodamine 4-chloroa-linolatatam, bis {2-methyl- (4-dimethylamino) phenol} {( 2,5-dimethylamino) fur} methane.

 [0033] In the reversible thermosensitive composition according to the present invention, the electron accepting compound and the Z or electron donating compound may be used in combination of a plurality of types of compounds.

[0034] The reversible thermosensitive composition according to the present invention essentially comprises the hydroxyphenylhydroxyalkylamide compound and an electron-donating color-forming compound. These compounds can be blended in an optional ratio as required. The amount of the electron-donating coloring compound is preferably 4 to 10 mol per 1 mol of the hydroxyalkylamide compound (electron-accepting compound). More preferably, it is 5-7 mol. Also, if necessary, a matrix polymer, a vehicle, a dispersant, a surfactant, an antistatic agent, a lubricant, an antioxidant, an ultraviolet absorber, a coloring Various additives such as a stabilizer, a decolorization accelerator, and a sensitizer can be further included. [0035] The reversible thermosensitive composition according to the present invention may further comprise a solvent or a vehicle for dissolving or dispersing the above components. When the above components are dissolved or dispersed in a solvent, the composition according to the present invention can be used as an ink, for example, a gel ink. The pattern drawn by the ink can be colored or erased by temperature control.

 [0036] 3. Reversible thermosensitive recording material

 The reversible thermosensitive recording material according to the present invention comprises a recording element containing the hydroxyphenol hydroxyalkylamide compound of the general formula (I) and an electron-donating color former. . This recording element may include the reversible thermosensitive composition described above. This recording material can be colored or discolored and decolored by controlling the temperature. Therefore, the reversible thermosensitive recording material according to the present invention can be said to be a reversible thermochromic recording material.

 [0037] The reversible thermosensitive recording material according to the present invention can be a recording material of any shape as long as it has such a recording element.

 [0038] For example, a matrix polymer or a mixture in which an electron-accepting compound and an electron-donating color-forming compound are uniformly dispersed in a vehicle may be used as a single film, or may be coated on a support. It is possible to form a recording layer in the form of a film by forming a recording layer in the form of a film.

 Further, a mixture of the electron-accepting compound of the general formula (I) and an electron-donating color-forming compound, and if necessary, uniformly holding the mixture in a matrix polymer or the like is used as a powder. The recording material may be a recording element that has been formed, or a recording element in which an electron-accepting compound and an electron-donating color-forming compound are encapsulated in microcapsules. Such a recording material is used, for example, as an electrostatic toner. Such powders or microcapsules may contain the matrix polymer or may contain the various additives. Furthermore, these powders or microcapsules can be encapsulated in microcapsules, if necessary, with further additives to form recording elements. A material in which such a powder or a microcapsule is adhered or fixed on a support is also one of the reversible thermosensitive recording materials according to the present invention.

[0040] The electron accepting compound and the electron donating color forming compound which can be used in the present invention are described below. As the matrix polymer or vehicle to be dispersed or retained, the recording material can uniformly disperse or retain the electron-accepting compound, the electron-donating color-forming compound, and other additives as necessary, and It is not particularly limited as long as it does not inhibit the color development or decoloration of.

 [0041] Specific examples of such a matrix polymer include polychlorinated vinyl, vinyl chloride-vinylinoleate copolymer, cenorellose-based polymer, polystyrene, styrene-based copolymer, acrylic polymer, gen-based polymer, and the like. Examples include polyester, polyurethane, polycarbonate, and polybutyl alcohol. As the vehicle, those generally used in the field of printing can be used.

 In the case where the composition containing an electron-accepting compound and an electron-donating color-forming compound is arranged in a layer on a support, the support may be transparent or translucent. Alternatively, opaque polymer films or sheets, synthetic paper and processed paper, glass plates, metal plates, etc. are used, and the recording layer is provided directly on the support or the adhesion between the support and the recording layer is improved on the support. For this purpose, an undercoat layer may be provided, and a recording layer may be provided thereon. It is also preferable to select such an undercoat layer that has an effect of imparting heat insulation and the like in addition to the improvement of adhesion.

When the recording material is in the form of a sheet, a force that enables recording with a thermal head is prevented, the surface of the recording material is prevented from fusing to the thermal head, the abrasion resistance of the recording layer is improved, and A transparent protective layer may be provided on the surface of the recording material to prevent the recording layer from being contaminated by harmful gas or the like. The protective layer can be formed by vapor deposition of an inorganic substance, coating with a polymer solution or the like, or can be formed by laminating a polymer film. In order to improve the adhesion between the protective layer and the recording layer, an intermediate layer such as an adhesive layer or an adhesive layer may be provided. Further, in order to improve the properties of the protective layer or the recording layer, various additives such as a surfactant, an antistatic agent, a lubricant, an antioxidant, and an ultraviolet absorber may be added to the protective layer or the intermediate layer. . Further, an ultraviolet absorbing layer made of an ultraviolet absorbing polymer may be provided as an intermediate layer. Such an ultraviolet absorbing layer may be provided independently of the above-mentioned protective layer or intermediate layer, or may contain the above-mentioned additive at the same time. Also, when the recording material is in the form of a sheet, physical properties such as curl prevention are improved. For better performance, a back coat layer may be provided.

 [0044] Since the reversible thermosensitive recording material of the present invention can be used in the form of a layer on a support, it is possible to use an electron-accepting compound, an electron-donating compound and, if necessary, other additives. The reversible thermosensitive recording material can be formed by applying a solution or dispersion containing the composition onto a support by various coating methods such as bar coating and spin coating. The recording layer provided on the support surface preferably has a thickness of 1 μm to 30 μm when dried, and more preferably 2 m to 10 m. The recording material of the present invention can be displayed by coloring the color with a heat-sensitive printer such as a fax or a thermal transfer printer, a heat roll, etc., and blowing hot air at a decoloring temperature, heating with a hot stamp, a heat roll, etc. Can be used to erase the color.

 The reversible thermosensitive recording material of the present invention comprises a coloring agent alone in a recording layer or in a layer other than the recording layer, for example, a support, an undercoat layer, a protective layer, an adhesive or pressure-sensitive adhesive layer. From the color (X) to the color (Y) in which the color of the colorant alone and the color of the electron-donating color-forming compound in the colored state are mixed, or vice versa, from (Y) to (X) You can make a change. The type and amount of the coloring agent that can be used here are arbitrary, but when they are present in the recording layer, the coloring reaction between the electron-accepting compound and the electron-donating color-forming compound should not be inhibited. Should be selected. If a colorant is present in the recording layer or in a layer other than the recording layer, it should be selected so that the change in color or change in contrast is appropriate.

 [0045] The reversible thermosensitive recording material of the present invention is a recording material comprising the electron accepting compound of the above general formula (I) and the electron donating color forming compound in a predetermined character, figure or pattern on a support. A recording layer can also be formed. That is, when the recording layer is heated to the color development temperature range, a part or the whole of the recording layer develops or discolors, thereby enabling recording or display. At this time, by forming a plurality of recording layers that develop or change colors into different colors in a pattern such as a stripe shape or a matrix shape, a plurality of colors can be developed.

Further, in the present invention, the recording layer may be formed so as to cover the underlayer in a color-developed state. Therefore, when a predetermined character, figure or pattern is formed on the support in advance, and the recording layer is uniformly laminated on the predetermined character, figure, or pattern, the temperature control becomes difficult. Therefore, by coloring or decoloring the recording layer, part or all of the recording layer is colored or decolored or discolored, and part or all of the characters, figures or patterns on the support are concealed or transparent. Thus, reversible recording or display becomes possible. Also, predetermined characters, figures, and patterns can be formed on both the recording layer and the support and used in combination. Incidentally, the recording material in the present invention is a term including a display material.

 [0047] 4. Decoloring process

 The color developing and erasing process according to the present invention is carried out at a temperature at which both the electron-donating color-forming compound and the electron-accepting compound in the reversible thermosensitive composition or the reversible thermosensitive recording material are melted by a suitable heat source. A color is developed by heating and then rapidly cooled to maintain a stable color development state, and the color is decolorized by heating to a decoloring temperature range below the color development temperature where the melting reaction and the reverse reaction occur. It is.

 [0048] Examples of the heat source include a thermal head, a laser beam, a hot roller, a hot stamp, hot air, high frequency heating, radiant heat from a heat transfer heater, a hot pen, a heated thermostatic oven, and infrared irradiation. In particular, when heat is partially applied, a thermal head, a laser beam, a heat sink, or the like is preferable.

 [0049] As a specific coloring method, for example, after the recording layer is partially and shortly heated by a thermal head or the like, the recording layer can be rapidly cooled by removing the heat source, and a colored state can be obtained. At that time, it is possible to cool sufficiently by keeping the surrounding environmental temperature at about room temperature.However, by performing the local heating in a short time, the temperature difference with the non-heated portion other than the heated portion is combined. As a result, rapid cooling can be ensured. More specifically, the color developing temperature in the color developing / erasing process of the present invention is 90 ° C. or higher, preferably 100-140 ° C.

 On the other hand, to change the reversible thermosensitive recording material from the color-developed state to the decolored state, for example,

 (1) Once the reversible thermosensitive recording material is reheated to a temperature at which both of its included components, the electron-donating color-forming compound and the electron-accepting compound, are melted, that is, the color-forming temperature or higher. A method of gradually cooling from a heated state, and

 And (2) a method of reheating to a temperature slightly lower than the coloring temperature.

[0051] To perform the slow cooling in (1), a method of performing temperature control for storing heat in a peripheral environment or a peripheral portion of a support or the like during reheating by the heat source and using the temperature is used. To Can be used. More specifically, after heating to a temperature higher than the temperature at which the color can be erased, for example, the color development temperature, the temperature of the recording layer is gradually decreased at such a rate as to erase the color.

 As a method of reheating to a temperature slightly lower than that of (2), the applied voltage and pulse width of the thermal head are adjusted, and a temperature slightly lower than that when the applied energy itself is colored, for example, The decoloring temperature may be set. In the present invention, the decolorization temperature is 60 to 130 ° C, preferably 80 to 120 ° C.

 [0053] In both of the methods (1) and (2) for changing the material from the color-developed state to the decolored state, the cooling rate and the stamping energy are adjusted to change the material from the decolored state to the colored state. The heating means used at this time can be used in common.

 That is, the development of the decolored state can be achieved by the same thermal control as that for obtaining the color-developed state, except that the temperature conditions described in (1) or (2) above are adjusted. Therefore, the heating means that can be used to obtain the color-developed state and the heating means that can be used to obtain the decolored state can be used for both by adjusting the energy applied to the recording material. It is.

 [0055] More specifically, when used as a reversible thermosensitive recording material, it is widely used for facsimile and the like, and is applied to ordinary thermal printers and bar code printing. It can be colored by a thermal printer with a head or a heat roll.

 [0056] As a method of gradually cooling, the recording material is brought into contact with an electric heater and a hot plate heated to a coloring temperature, and then the supply of energy for heating is stopped, and the support and the like are heated. Then, it can be gradually cooled by a method such as cooling.

 [0057] As a method of heating to a temperature slightly lower than the color development temperature, the color is erased by a method such as blowing hot air at an erasing temperature, heating with a hot stamp, a heat roll, a hot plate, or an on-surface heating element. be able to.

[0058] In addition, a recording material is applied to a film or paper by using a thermal printer having a thermal head, such as a thermal transfer printer, which is applied to a normal thermal printer or a bar code printing widely used for facsimile and the like. And the energy that is applied to the recording material is the decolorizing temperature. After the adjustment, the color is erased by applying energy to the entire surface of the recording material.

 Further, if a thermostat is used, a large amount of recorded matter can be erased at a time.

 The reversible thermosensitive recording material of the present invention can be applied to sheet-like materials or cards having a recording layer, and further to use as a toner or as an ink for writing, etc. It is also possible to appropriately combine two or more kinds.

 [0060] Further, it is also possible to use those having different coloring temperatures in combination with ^ a, and in that case, it is also possible to efficiently express multicolor.

 [0061] The present invention is described below with reference to examples.

[0062] Synthesis Example 1

 Synthesis of N- (4-hydroxyphenyl) -12-hydroxystearamide

 32.7 parts by weight of P-aminophenol, 88.35 parts by weight of 12-hydroxystearic acid, and 0.24 parts by weight of p-toluenesulfonic acid were added to 200 parts by weight of xylene, and the mixture was added at 220 ° C for 2 hours. After distilling off water while distilling, xylene was removed to obtain a black wax-like substance. This substance was recrystallized from methyl ethyl ketone (MEK) to obtain 50 parts by weight of a white powdery substance (44% yield). Melting point was 141 ° C. By IR and DSC measurement of this substance

, N- (4-hydroxyphenyl) -12-hydroxystearamide. The obtained IR ^ vector and DSC chart are shown in Figs. The measured values obtained from these were as follows.

IR spectrum (absorption position / cm ^ ¹ )

 O—H (phenol, alcohol): around 3300

 N-H (amide, stretch): around 3300

 C—H (methylene;): 2920, 2850

 C—H (methyl): 2960

 C = 0 (amide carbohydrate): 1670

 Feel: 1520, 1600

 N—H (amide, bending): 1540

Kaoru呑族_Ό over置椽body: 830 DSC endothermic peak: 141. 71 ° C

 Endothermic onset temperature: 124. 89 ° C

 Endothermic end temperature: 156. 03 ° C

[0063] Synthesis Example 2

 Synthesis of N- (3-hydroxyphenyl) -12-hydroxystearamide

 Using P-aminophenol as m-aminophenol, a black WAX-like product was obtained in the same manner as in Synthesis Example 1. After washing 50 parts by weight of this product with toluene, it was recrystallized with butyl acetate to obtain 7.8 parts by weight (15.6% yield) of a light brown powder. Melting point was 117 ° C. The substance was confirmed to be N- (3-hydroxyphenyl) -12-hydroxystearamide by IR and DSC measurements. The obtained IR ^ vector and DSC chart are shown in Figs. The measured values obtained for these forces were as follows.

IR spectrum (absorption position cm ^ ¹ )

 OH (phenol, alcohol): around 3300

 N-H (amide, stretch): around 3300

 C—H (methylene;): 2920, 2850

 C—H (methyl): 2960

 CO (amide carbohydrate): 1650

 Feel: 1500, 1610

 N—H (amide, bending): 1550

 Fuenoren: 1230

 H 呑 n 族 m m-m 置 ki: 770.730

 DSC endothermic peak: 117. 07 ° C

 Endotherm temperature: 105. 38 ° C

 Endothermic end temperature: 125.62 ° C

[0064] Synthesis Example 3

 Synthesis of N- (4-hydroxyphenyl) -12-hydroxypentadecaneamide

N- (4-Hydroxyphenyl) -12-hydroxypentadecaneamide was obtained in the same manner as in Synthesis Example 1 except that 12-hydroxystearic acid was changed to 12-hydroxypentadecanoic acid. Fusion The point was 151 ° C. The obtained IR ^ vector and DSC chart are shown in Figs. The measured values for these forces were as follows.

IR spectrum (absorption position / cm ^ ¹ )

 OH (phenol, alcohol): around 3300

 N-H (amide, stretch): around 3300

 C—H (methylene;): 2920, 2850

 C—H (methyl): 2960

 CO (amide carbohydrate): 1660

 Feel: 1500, 1610

 N—H (amide, bending): 1550

 Fuenoren: 1230

Kaoru呑旌_Ό置橼body: 830

 DSC endothermic peak: 150.89 ° C

 Endotherm temperature: 147.02 ° C

 Endothermic end temperature: 155.62 ° C

Example 1

 0.01 part by weight of N- (4-hydroxyphenyl) -12-hydroxystearamide prepared in Synthesis Example 1 and 3- (4-ethylethyl-2-ethoxyphenyl) -3- (1-ethyl-2-) A composition containing 0.004 parts by weight of methylindole 3 yl) 4-azaphthalide was placed on a slide glass and heated to 140 ° C. to develop a deep blue color. When the slide glass was quenched with ice water, the color development was maintained. When the colored product was left in a thermostat at 100 ° C, the color was erased. When the decolorized material was heated again to 140 ° C., the color developed as in the initial stage. From these, it was confirmed that coloring and decoloring of this composition could be repeatedly performed.

Example 2

In the same manner as in Example 1, except that N- (4-hydroxyphenyl) 12-hydroxystearamide was changed to N- (3-hydroxyphenyl) 12-hydroxystearamide. And decolorization were confirmed. When the composition was placed on a slide glass and heated to 100 ° C., a deep blue color developed. When this slide glass was quenched with ice water, its color development was maintained. I was When the colored product was left on a hot plate at 75 ° C., the color was erased. When the decolorized material was heated again to 100 ° C, the color developed as in the initial stage. From these results, it was confirmed that this composition was capable of repeating coloring and decoloring.

Example 3

 N- (4-hydroxyphenyl) 12-hydroxystearamide of Example 1 was changed to N- (4-hydroxyphenyl) -12-hydroxypentadecaneamide, and 140 ° C calorific heat was applied at 120 ° C. The repetition of color development and color erasure was confirmed in the same manner as in Example 1 except that the color development and color erasure were performed, and it was confirmed that color development and color erasure could be repeated.

 Example 4

 Styrene acrylic ester copolymer: 20 parts by weight

 (Hymer TB-1000F (trade name) manufactured by Sanyo Chemical Industry Co., Ltd.)

 N- (4-hydroxyphenyl) -12-hydroxystearamide: 10 parts by weight

 Crystal Violet Lacton (CVL): 3.6 parts by weight

 The composition was heated and dissolved in 170 parts by weight of tetrahydrofuran (THF) to prepare a solution of a reversible thermosensitive recording material. This solution was applied to a 100-m-thick white polyethylene terephthalate film (manufactured by Toray Industries, Inc.) using a wire bar, and then heated and dried at 100 ° C to obtain a 4-m-thick reversible film. A recording layer made of a thermosensitive recording material was provided to produce a recording material. When this recording material was heated to 140 ° C and cooled to room temperature (20 ° C), a blue-violet color was formed. This recording material was heated to 100 ° C for 1 second, cooled to room temperature, heated to 140 ° C, and then cooled to room temperature. As a result, reversal of color erasing and color development was possible. The optical densities of the color-developed state and the decolored state were measured using a Macbeth densitometer RD-915 (trade name), and the OD values were 0.80 in the color-developed state and 0.07 in the decolored state. An excellent recording material was obtained.

 Example 5

 Styrene acrylic ester copolymer (Hymer TB-1000F (trade name) manufactured by Sanyo Chemical Industries, Ltd.): 20 parts by weight

 N- (4-hydroxyphenyl) -12-hydroxystearamide: 10 parts by weight

3— (4—Jethylamino—2—Ethoxyphenyl) —3— (1—Ethyl-2-methylindole) 3 yl) 4-azaphthalide (Blue-63 (trade name, manufactured by Yamamoto-Danisei Co., Ltd.)): 4.2 parts by weight The composition containing the above components was mixed with 17.6 parts by weight of toluene and 17.2 parts by weight of methyl ethyl ketone. It was dissolved in a mixed solvent consisting of 6 parts by weight and 67.4 parts by weight of dimethylacetamide to prepare a solution of a reversible recording material. This solution is applied to a 75 μm-thick white polyethylene terephthalate film using a wire bar, and then heated and dried at 100 ° C to form a 7-m-thick reversible thermosensitive recording material that also has power. And a recording material was prepared. The recording material was heated to 140 ° C. on a hot plate and cooled to room temperature. The recording material was heated at 110 ° C. for 1 second, cooled to room temperature, heated to 140 ° C., and then cooled to room temperature. As a result, decoloring and color development could be performed reversibly. At this time, the optical densities in the color-developed state and the decolored state were measured using a Macbeth densitometer RD-915 (trade name). Value, and an excellent recording material was obtained.

[0070] Comparative Example 1

 Example 4 was repeated except that N- (4-hydroxyphenyl) 12-hydroxystearamide was changed to 10 parts by weight of N- (4-hydroxyphenyl) -stearamide (melting point 133 ° C). Similarly, a recording material was prepared. When this recording material was heated to 140 ° C. and cooled to room temperature (20 ° C.), a blue-violet color developed. The operation of heating the recording material to 100 ° C, cooling to room temperature, heating to 140 ° C, and cooling to room temperature was repeated. As a result, decoloring and color development could be performed reversibly. The optical densities of the color-developed state and the decolored state at this time were measured using a Macbeth densitometer RD-915. The OD values were 0.65 in the color-developed state and 0.07 in the decolored state. It was confirmed that the recording material was inferior to the recording material of the present invention.

[0071] Evaluation of storage stability

 The recording materials of Example 4 and Comparative Example 1 were printed with a thermal head (printing energy 0.25 mj / dot), left in a constant temperature bath at 40 ° C for 24 hours, and the optical density before and after storage at this time was measured. The measurement was performed using a densitometer RD-915 (trade name) to evaluate the storage stability of the printed matter. Storage stability was calculated according to the following equation.

Print storage rate (%) = {(OD value of printed matter after storage, base OD value after storage) / (OD value of printed matter before storage-base OD value before storage)} X 100 [Table 1]

[0073] Comparative Example 2

 As in Example 4, except that the electron accepting compound was (HO) PhCOOC H

 3 18 37

 A recording material was prepared.

[0074] Comparative Example 3

 Recorded in the same manner as in Example 4, except that the electron-accepting compound was CHP (O) (OH).

 22 45 2

 Materials were made.

[0075] Comparative Example 4

 Except that the electron accepting compound was HOPhC H NHCOC H NHCONHC H

 In the case of 2 4 5 10 18 37, a recording material was produced in the same manner as in Example 4.

 Evaluation of Coloring Temperature, Decoloring Temperature, Erased Items, and Storage Stability Items

 For the recording materials of Example 4 and Comparative Examples 2-5, the temperature at which color development was possible (color development temperature), the temperature at which color was erasable (decolorization temperature), the time required for erasure (erasability), and 40 ° C The color development stability (storage stability) when kept at 保持 was evaluated. The results obtained were as follows.

 [0077] [Table 2]

Here, the evaluation criteria of the storage stability were determined by the following criteria from the print preservation rate when stored at 40 ° C for 24 hours.

 〇: More than 80%

 △: More than 40% and 80% or less

 X: 40% or less

Example 6—10 N-4- (Hydroxyphenyl) -12-hydroxystearamide was changed to the amide compound shown in Table 3, the compounding amount in the table was used, and color development and decoloration were confirmed by heating to each temperature and then cooling. A color development and decoloration test was performed in the same manner as in Example 5, except that the test was performed. The amounts in the table are parts by weight based on 20 parts by weight of the styrene acrylic ester copolymer.

[0079] [Table 3]

 * N4HP 12HSA: N— (4-hydroxyphenyl) 12-hydroxystearamide * N3HP 12HSA: N— (3-hydroxyphenyl) 12-hydroxystearamide * N4HP 12HPA: N— (4-hydroxyphenyl) —12-Hydroxy dd pentadecaneamide

Example 11-17

 The same procedure as in Example 5 was repeated except that the leuco dye was changed to the leuco dye shown in the table below.

 P

 Produced. To confirm color development, use a commercially available fax (UF-A6CL (trade name) manufactured by Matsushita Electric

 o Co., Ltd.) and printing without a film. The decolorization test was performed under the same conditions as in Example 5. The amounts in the table are parts by weight based on 20 parts by weight of the styrene acrylic ester copolymer.

 [0081] [Table 4]

Combination: 配合 Formulation S Color development Decolorization Amide compound Leuco dye

 (Parts by weight) (parts by weight) 0D value OD value Example 11 {4ΗΡ12} 11.2 S-205 3.0 0.95

 Example 12 Ν4ΗΡ12ΗΡΑ 11.4 0DB 2.8 1.16 0.20 Example 13 Ν4ΗΡ12ΗΡΑ 11.2 Black15 3.0 0.06 Example 14 Ν4ΗΡ12ΗΡΑ 11.4 0DB-7 2.8 1.16 0.20 Example 15 Ν4ΗΡ12ΗΡΑ 11.2 PSD-150 3.0 0.06 Example 16 Ν4ΗΡ12ΗΡΑ 11.4 PSD-300A 2.8 1.16

Example 17 Ν4ΗΡ12ΗΡΑ 11.2 Black173 3.0 S-205: Fluoran leuco dye manufactured by Yamada Chemical Industry Co., Ltd.

 ODB: Fluoran-based leuco dye manufactured by Yamamoto-Daisei Co., Ltd.

 Blackl5: Fluoran leuco dye, manufactured by Yamamoto Iidai Co., Ltd.

 ODB-7: Fluoran leuco dye manufactured by Yamamoto Kasei Co., Ltd.

 PSD-150: Nippon Soda Co., Ltd., fluoran leuco dye

 PSD-300A: Fluoran leuco dye manufactured by Nippon Soda Co., Ltd.

 Blackl73: Fluoran leuco dye manufactured by Yamamoto Kasei Co., Ltd.

Example 18—21

 A color development and decoloration test was performed in the same manner as in Example 5, except that the matrix polymer was changed to the matrix polymer shown in the table below.

[Table 5]

Saturated polyester 1: Byron 240, manufactured by Toyobo Co., Ltd.

 Saturated polyester 2: Byron GK-640, manufactured by Toyobo Co., Ltd.

 Saturated copolymerized polyester urethane: Byron UR-1400, manufactured by Toyobo Co., Ltd. Polystyrene: Hymer ST-120, manufactured by Sanyo Chemical Industries, Ltd.

 Example 22—24

 Color development and decoloration tests were carried out in the same manner as in Example 18, except that the mixing ratio of the amidy conjugate and the leuco dye was as shown in the following table. The amounts in the table are parts by weight based on 20 parts by weight of the saturated polyester 1.

 [0085] [Table 6]

Example 25-30

 Color development and decoloration tests were carried out in the same manner as in Example 5, except that the mixing ratio of the amidy conjugate and the leuco dye was as shown in the following table. The amounts in the table are parts by weight based on 20 parts by weight of the styrene acrylic ester copolymer.

[Table 7] 7

Example 31 (Preparation of recording material using amide compound dispersion system)

Saturated polyester (Byron GK-640 (trade name), manufactured by Toyobo Co., Ltd.): 15 parts by weight 3- (4-Jetylamino-2-ethoxyethoxy) -3- (1-ethyl-2-methylindole-3-yl)- 4-azaphthalide (Blue-63 (trade name, manufactured by Yamamoto Kasei Co., Ltd.)): 3 parts by weight UV absorber CFAST-500 (trade name, manufactured by Johoku Chemical Co., Ltd.): 1 part by weight The composition containing the above components is It was dissolved in a mixed solvent consisting of 50 parts by weight of toluene and 50 parts by weight of methyl ethyl ketone. In this solution,

 N- (4-hydroxyphenyl) -12-hydroxystearamide: 8 parts by weight

The mixture was pulverized and dispersed for 90 minutes with a sand grinder (TSG-4H (trade name) manufactured by IMETUS Co., Ltd.) to obtain a reversible recording material dispersion having an average particle size of about 1 μm. .

This dispersion was applied to a 75 μm-thick white polyethylene terephthalate film using a wire bar, and then heated and dried at 80 ° C to form a thick reversible heat-sensitive recording material with a recording layer that also had the power. And a recording material was produced. This recording material was printed using a commercially available FAX (UF-A6CL (trade name, manufactured by Matsushita Electric Industrial Co., Ltd.)) without passing through a film, and a deep blue color was formed. The recording material was heated with a heat roller at 110 ° C for 1 second, cooled to room temperature, and the fax printing operation was repeated. Could be done. At this time, the optical density in the color-developed state and the decolored state was measured using a Macbeth densitometer.

When measured using RD-915 (trade name), it showed an OD value of 1.16 in the color-developed state and 0.09 in the decolored state, and an excellent recording material was obtained.

Example 32 (Preparation of powdery recording material)

 Styrene acrylic ester copolymer (Hymer TB-1000F (trade name) manufactured by Sanyo Chemical Industries, Ltd.): 20 parts by weight

 N- (4-hydroxyphenyl) -12-hydroxystearamide: 10 parts by weight

 3— (4—Jethylamino—2—Ethoxyphenyl) —3— (1—Ethyl-2-methylindole)

3 yl) 4-azaphthalide (Blue-63 (trade name, manufactured by Yamamoto-Danisei Co., Ltd.)): 4.2 parts by weight The composition containing the above components was mixed with 17.6 parts by weight of toluene and 17.2 parts by weight of methyl ethyl ketone. It was dissolved in a mixed solvent consisting of 6 parts by weight and 67.4 parts by weight of dimethylacetamide to prepare a reversible recording material solution. This solution was flowed thinly and evenly on a polyethylene sheet, and allowed to stand in a thermostat at 60 ° C. for 3 days to obtain a dark blue dry solid. Using a sample mill (SK-M3 (trade name), manufactured by Kyoritsu Riko Co., Ltd.), a powdery reversible thermosensitive recording material was obtained. This powder was confirmed for the repeatability of coloring and decoloring in the same manner as in Example 1, and showed the same behavior as in Example 1.

Example 33 (Production of Thermal Ink)

 Powdered recording material of Example 32: 15 parts by weight

 Water: 135 parts by weight

 The mixture containing the above components is pulverized and dispersed for 60 minutes by a sand grinder (TSG-4H (trade name) manufactured by IMETUS Co., Ltd.), and an aqueous dispersion of a reversible recording material having an average particle size of about 1 μm is obtained. Obtained. 15 parts by weight of this aqueous dispersion

Reversible recording is possible by mixing 6 parts by weight of a 5% aqueous solution of polybutyl alcohol (using Gohsenol GM-14 (trade name) manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) as the polybutyl alcohol and mixing and stirring the composition. Thus, a heat-sensitive ink capable of obtaining a clear image was obtained. This solution was applied on an 80 μm polypropylene film (upo FPG80 (trade name) manufactured by Upo Corporation) using a painting brush to obtain a reversible recorded image. When this image was checked for repetition of color development and decoloring in the same manner as in Example 1, the results were similar to those in Example 1. Behaved.

 Further, after applying the above-mentioned thermal ink to a 75 μm-thick white polyethylene terephthalate film using a wire bar, it is heated and dried at 80 ° C. to form a recording layer made of a reversible thermosensitive recording material having a thickness. Was provided to produce a recording material. This recording material was printed using a commercially available FAX (UF-A6CL (trade name, manufactured by Matsushita Electric Industrial Co., Ltd.)) without passing through a film, and a deep blue color was formed. This recording material was heated with a heat roller at 120 ° C. for 1 second, cooled to room temperature, and the above-described fax printing operation was repeated. As a result, decoloring and color development could be performed reversibly. At this time, the optical densities in the color-developed state and the decolored state were measured using a Macbeth densitometer RD-915 (trade name). An OD value of 06 showed an excellent recording material.

Although not limiting the present invention, the above results suggest that the coloring / decoloring mechanism of the reversible recording material of the present invention and the structure of the hydroxyphenylhydroxyalkylamide compound have the following relationship. are doing. Although the coloring temperature has a relationship with the melting point, it seems that the position of the long-chain alkyl group having a hydroxyl group having a hydrogen bonding function also has an effect. That is, among the hydroxyphenylhydroxyalkylamide conjugates of the present invention, N- (4-hydroxyphenyl) -12-hydroxypentadecaneamide has a melting point of N- (4-hydroxyphenyl)- It is about 10 ° C higher than 12-hydroxystearamide, but its coloring temperature as a recording material is about 10 ° C lower. This means that the position of the hydrogen bond from the amide group is the same for both, but the distance from the alkyl group end is shorter for N- (4-hydroxyphenyl) -12-hydroxypentadecaneamide. Since the steric hindrance has been reduced, the amide compound alone is considered to have a higher melting point. On the other hand, it is presumed that steric hindrance was generated in hydrogen bonding due to the effects of leuco dyes and matrix polymers, etc., and that the hydrogen bonding ability was slightly weakened, the apparent melting point was lowered, and the coloring temperature was lowered. are doing. On the other hand, it is considered that the acidity of the amidy conjugate has an effect on the decoloring performance of the recording material. That is, in the hydroxyphenylhydroxyalkylamide compound of the present invention, N- (3-hydroxyphenyl) -12-hydroxystearamide has a higher acidity than N- (4 hydroxyphenyl) 12-hydroxystearamide. As a result, it takes some time for decoloring, so there is no practical problem, but it is presumed that the decoloring density has become slightly higher. Yes. Further, regarding the storage stability, it is effective to have a hydrogen bonding group as described above. The hydroxyphenol hydroxyalkylamide compound in the present invention is capable of forming, decoloring, The above speculation suggests that the storage stability was well balanced because the hydrogen bond position, acidity, and alkyl chain length were preferred. Industrial applicability

 The reversible thermosensitive recording material using the electron accepting compound according to the present invention is excellent in color stability and erasability, color development sensitivity, balance between color development temperature and color erasure temperature, and storage stability against heat in a color development state. I have. Therefore, it can be generally used as an erasable or rewritable recording material. In particular, since the balance between the coloring temperature and the erasing temperature is appropriate, the degree of freedom of hardware for forming or erasing images is increased. In addition, by achieving high levels of color sensitivity, erasability, and storage stability, it can be used for general-purpose thermal printers such as fax machines, and can be applied to various applications.

Claims

The scope of the claims

 [1] A hydroxyphenylhydroxyalkyl amide compound represented by the following general formula (I):

 [Formula 1] 卡

 c

H

 2

 G m

 (Where n is an integer of 1 to 3, and OCI A is a hydroxyl group bonded to a carbon atom other than the terminal carbon.

 H H

 A straight-chain hydroxyalkyl group. )

 [2] The hydroxyphenol hydroxyalkylamide compound according to claim 1, wherein A in the general formula (I) is represented by the following general formula (Π).

 [Formula 2]

CH ₂ CH II

 k

(Here, m and 1 are each independently an integer of 0 or more, and k represents an integer of 1 or more.)

 3. The hydroxyphenylhydroxyalkylamide compound according to claim 2, wherein m + 1 is from 6 to 23.

 4. The hydroxyphenylhydroxyalkylamide compound according to claim 2, wherein k is 1 or 2.

 5. The hydroxyphenylhydroxyalkylamide compound according to claim 1, wherein m is 10, 1 is 5, and k is 1.

 5. The hydroxyphenylhydroxyalkylamide compound according to claim 1, wherein m is 10, 1 is 2, and k is 1.

A reversible heat-sensitive set, comprising the hydroxyphenol hydroxyalkylamide compound according to claim 1 and an electron-donating color-forming compound. Adult. [8] The reversible thermosensitive composition according to claim 7, wherein the electron-donating color-forming compound is a leuco dye.

 [9] A recording element comprising the hydroxyphenylhydroxyalkylamide compound according to [1] and the electron donating color-forming compound according to [1]. , Reversible thermosensitive recording material.

 [10] The reversible thermosensitive recording material according to claim 9, wherein the recording element further comprises a matrix polymer or a vehicle.

[11] The reversible thermosensitive recording material according to claim 9 or 10, wherein the shape of the recording element is a film.

[12] The reversible thermosensitive recording material according to claim 9 or 10, wherein the shape of the recording element is a powder.

[13] A reversible thermosensitive recording material, wherein the recording element according to claim 9 or 10 is encapsulated in a microcapsule.

 [14] A reversible thermosensitive recording material, wherein the recording element according to any one of claims 8 to 13 is disposed on a support.

 [15] A reversible thermosensitive recording material comprising a recording element comprising the hydroxyphenylhydroxyalkylamide compound according to claim 1 and an electron-donating color-forming compound. By heating to a coloring temperature at which both the hydroxyphenylhydroxyalkylamidide compound and the electron-donating color-forming compound undergo a melting reaction, the color is formed, and then rapidly cooled to stably maintain a color-developed state. A color-decoloring process characterized in that the color is erased by heating to a color-deleting temperature range in which the melting reaction and the reverse reaction, which are lower than the color-forming temperature, occur.