JPH11129623A - Reversible heat discoloration composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reversible heat discoloration composition effective in a toy, decoration or temperature indicating material field by providing a reversible heat discoloring function for transferring to a color developing state by heating from a color erasing state and resetting to the erasing state by a temperature drop from the developing state. SOLUTION: The reversible heat discoloration composition comprises an electron donative colorational organic compound, an alkoxyphenol compound represented by the following general formula (1) wherein R is an alkyl group, and a compound of a reaction medium reversibly bringing about an electron donative or acceptive reaction by the organic compound and the alkoxyphenol compound in a specific temperature range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a reversible thermochromic composition. Specifically, the present invention relates to a reversible thermochromic composition which reversibly generates a color-developed state and a decolored state by a temperature change.
More specifically, the present invention relates to a reversible thermochromic composition having a reversible color-changing function that exhibits a color-developed state when heated from a decolored state and exhibits a decolored state when cooled from the color-developed state.

[0002]

2. Description of the Related Art Heretofore, several proposals have been disclosed for a reversible thermochromic composition which causes a reversible color change in a specific temperature range by an electron transfer reaction (Japanese Patent Publication No. 51-35).
No. 414, JP-B-51-44706, JP-B-51-44708, JP-B-52-7776, JP-B-1-17154, JP-B1-2939.
No. 8, JP-A-7-186546, etc.). The proposal for the conventional reversible thermochromic composition described above starts decoloring in the process of raising the temperature from the color-developing state, presents a complete decoloring state at a specific temperature or higher, starts color development in the subsequent temperature-lowering process, and starts the color-developing state. It is mainly provided with a function of exhibiting a reversible thermochromic property (see FIG. 3) that returns to the temperature range, and is applied to the field of temperature indicating materials and toys. Further, an attempt to reversibly develop a color-developed state by heating from a decolored state has been disclosed in Japanese Patent Publication No. 2-23.
No. 592. The proposal utilizes the temperature dependence of the acid dissociation of the acid phosphate compound, and exhibits the discoloration behavior, but the coloring density is insufficient, and further, upon microencapsulation of the composition,
There are restrictions, and the applicability to the toy field, etc., is not satisfied.
Regarding reversible thermosensitive recording materials in the field of thermosensitive recording materials, several high-temperature coloring type proposals have been disclosed (JP-A-5-124360, JP-A-6-210954, etc.). This type of reversible thermosensitive recording material is constructed so that it can develop a colored state when applied at a temperature exceeding one hundred and several tens of degrees by a thermal head of a thermal printing device. Therefore, application to the temperature indicator, the toy field, and the like is restricted.

[0003]

SUMMARY OF THE INVENTION The present inventors have developed a reversible heat exhibiting a high-density color development state by heating from a decolored state in a living environment temperature range, and exhibiting a discoloration behavior of returning to the decolored state by cooling. The discoloring composition focuses on a new discoloring effect not only in various temperature indicating materials but also in the toy field, decoration, design field, etc., and as a result of intensive studies, a specific alkoxyphenol compound was converted to an electron-accepting compound. It was found that the above requirements were satisfied by applying the present invention, and the present invention was completed.

[0004]

SUMMARY OF THE INVENTION The present invention relates to (a) an electron-donating color-forming organic compound, and (b) at least one electron-accepting compound selected from alkoxyphenol compounds represented by the following general formula (1). , (C) the above (a), (b)
A compound that is a reaction medium that causes a reversible electron transfer reaction by an essential component, exhibits a color-developed state by heating from a decolored state, and exhibits a reversible color-changing function of exhibiting a decolored state by cooling from the color-developed state. The provided reversible thermochromic composition is required.

(R represents an alkyl group.) Further, the alkyl group of the alkoxyphenol compound represented by the general formula (1) is a straight-chain alkyl group having 3 to 18 carbon atoms. The component is a compound selected from chain hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and halogenated hydrocarbons, and the reversible thermochromic composition is contained in microcapsules. , And the discoloration temperature range must not exceed 90 ° C.
The reversible thermochromic composition of the present invention has a discoloration temperature range in a temperature range lower than that of a conventional reversible thermosensitive recording material, that is, a living environment temperature range of 90 ° C. or less, and discoloration due to heat such as hot water, cold water, and body temperature. Is possible. Another major feature of the present invention is that it is easy to adjust the color development temperature and the color erasure temperature, and the curve from the color erasure state to the color erasure state in the curve plotting the change in the color density due to the temperature change. It is also possible to obtain a hysteresis characteristic in which a path leading to a coloring state is greatly different.

The above-mentioned (a) electron-donating color-forming organic compounds include diphenylmethanephthalides known in the art,
Phenylindolyl phthalides, indolyl phthalides, diphenylmethane azaphthalides, phenyl indolyl azaphthalides, fluorans, styrinoquinolines, diaza rhodamine lactones, and the like.Examples of these compounds are given below. I do. 3,3-bis (p-dimethylaminophenyl) -6-dimethylaminophthalide, 3
-(4-diethylaminophenyl) -3- (1-ethyl-2-methylindol-3-yl) phthalide, 3,3
-Bis (1-n-butyl-2-methylindole-3-
Yl) phthalide, 3,3-bis (2-ethoxy-4-diethylaminophenyl) -4-azaphthalide, 3- [2
-Ethoxy-4- (N-ethylanilino) phenyl]-
3- (1-ethyl-2-methylindol-3-yl)
-4-azaphthalide, 3,6-dimethoxyfluoran,
3,6-di-n-butoxyfluoran, 2-methyl-6
-(N-ethyl-N-p-tolylamino) fluoran,
3-chloro-6-cyclohexylaminofluoran, 2
-Methyl-6-cyclohexylaminofluoran, 2-
(2-chloroanilino) -6-di-n-butylaminofluoran, 2- (3-trifluoromethylanilino)-
6-diethylaminofluoran, 2- (N-methylanilino) -6- (N-ethyl-Np-tolylamino) fluoran, 1,3-dimethyl-6-diethylaminofluoran, 2-chloro-3-methyl-6 -Diethylaminofluoran, 2-anilino-3-methyl-6-diethylaminofluoran, 2-anilino-3-methyl-6-di-n-butylaminofluoran, 2-xyridino-3-
Methyl-6-diethylaminofluoran, 1,2-benz-6-diethylaminofluoran, 1,2-benz-
6- (N-ethyl-N-isobutylamino) fluoran, 1,2-benz-6- (N-ethyl-N-isoamylamino) fluoran, 2- (3-methoxy-4-dodecoxystyryl) quinoline, Spiro [5H- (1) benzopyrano (2,3-d) pyrimidine-5,1 ′ (3 ′
H) Isobenzofuran] -3'-one, 2- (diethylamino) -8- (diethylamino) -4-methyl-, spiro [5H- (1) benzopyrano (2,3-d) pyrimidine-5,1 '( 3'H) isobenzofuran] -3'-
On, 2- (di-n-butylamino) -8- (di-n-
Butylamino) -4-methyl-, spiro [5H- (1)
Benzopyrano (2,3-d) pyrimidine-5,1 '
(3'H) isobenzofuran] -3'-one, 2- (di-n-butylamino) -8- (diethylamino) -4-
Methyl-, spiro [5H- (1) benzopyrano (2,3
-D) pyrimidine-5,1 '(3'H) isobenzofuran] -3'-one, 2- (di-n-butylamino) -8
-(N-ethyl-Ni-amylamino) -4-methyl-, spiro [5H- (1) benzopyrano (2,3-d)
Pyrimidine-5,1 '(3'H) isobenzofuran]-
3′-one, 2- (di-n-butylamino) -8- (di-n-butylamino) -4-phenyl and the like. Further, pyridine-based, quinazoline-based, bisquinazoline-based compounds, and the like, which are effective for expressing fluorescent yellow to red colors can be given.

In the present invention, in a composition comprising (a) an electron donating color-forming organic compound, (b) an electron accepting compound, and (c) a reaction compound of the two, a specific compound is used as the component (b). By applying the composition, a reversible thermochromic composition that exhibits a color-developed state in a heating process from a decolored state and a decolorized state in a temperature-decreasing process from the color-developed state in a living environment temperature range can be obtained. . The (b) electron-accepting compound is selected from the alkoxyphenol compounds represented by the general formula (1), and the alkyl group of the compound is preferably a straight-chain alkyl group having 3 to 18 carbon atoms. A system having an alkyl group having less than 3 or more than 18 carbon atoms does not satisfy practicality due to low color density. In consideration of more practical performance such as discoloration characteristics and color density, the alkyl group of the compound is more preferably a straight-chain alkyl group having 6 to 12 carbon atoms. These alkoxyphenol compounds have relatively low melting points, a small difference between the melting point and the cloud point, and have good crystallinity (see Table 5). In the reversible thermochromic composition of the present invention, in the heating process from the decolored state, the alkoxyphenol compound becomes a molten state or a dissolved state, and a color-developed state is generated by an electron transfer reaction with the component (a), and the color-developed state is obtained. It is presumed that the alkoxyphenol compound crystallizes during the cooling process from the state and separates from the component (a) to form a decolored state. Therefore, the discoloration temperature of the reversible thermochromic composition of the present invention can be set by selecting an alkoxyphenol compound having an appropriate melting point and cloud point as the component (b). It is also possible to adjust the discoloration temperature by lowering the melting point by using two or more alkoxyphenol compounds in combination. Examples of the alkoxyphenol compound are shown below. pn-propyloxyphenol, pn-
Butyloxyphenol, pn-pentyloxyphenol, pn-hexyloxyphenol, pn-
Heptyloxyphenol, pn-octyloxyphenol, pn-nonyloxyphenol, pn-
Decyloxyphenol, pn-undecyloxyphenol, pn-dodecyloxyphenol, pn
-Tridecyloxyphenol, pn-tetradecyloxyphenol, pn-pentyldecyloxyphenol, pn-hexyldecyloxyphenol, p
-N-heptyldecyloxyphenol and pn-octyldecyloxyphenol.

[0007] The reversible thermochromic composition of the present invention comprising the two components (a) and (b) can provide reversible heat coloring, but is limited to the adjustment of the discoloration temperature. By using the component (c), the discoloration temperature can be adjusted practically. In the alkoxyphenol compound represented by the general formula (1), as the number of carbon atoms in the linear alkyl group increases, the temperature difference between the melting point and the cloud point tends to be small, and the crystallinity tends to be high. By adding the component (c) in the product, an alkoxyphenol compound having higher crystallinity can be used at a discoloration temperature in a lower temperature range. Further, as described above, by selecting an appropriate (c) component, the curve from the decolored state to the color-developed state and the path from the color-developed state to the decolored state in the curve plotting the change in the color density due to the temperature change. , It is also possible to obtain hysteresis characteristics that differ greatly. (C)
Examples of the compound which is a reaction medium for reversibly causing the electron transfer reaction according to the above (a) and (b) in a specific temperature range include hydrocarbons, halogenated hydrocarbons, sulfides, ethers, ketones, and esters. , Acid amides,
Conventionally-used reaction media such as alcohols and waxes are all effective, and may be semi-liquid substances such as medium molecular weight polymers, and one or more of these compounds can be applied. When applied to microencapsulation and secondary processing using each of the above compounds, those having a low molecular weight evaporate out of the capsule system when subjected to high heat treatment. The above compounds are effective.

The hydrocarbons include chain hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons and the like. The saturated chain hydrocarbons include pentadecane, hexadecane, heptadecane, octadecane, nonadecane, and the like. Eikosan,
Examples include heneicosane, docosane, trichosane, tetracosane, pentacosane, hexacosane, heptacosane, octacosane, nonacosane, and triacontan. Examples of unsaturated chain hydrocarbons include 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 1-heneicosene, 1-docosene, 1-tricosene, 1-tetracocene, 1-pentacocene, 1-hexacocene, 1-heptacosene, 1-octacocene, 1-nonacocene, 1-
Triacontent and the like can be exemplified. Examples of the alicyclic hydrocarbons include cyclooctane, cyclododecane, n-pentadecylcyclohexane, n-octadecylcyclohexane, n-nonadecylcyclohexane, decahydronaphthalene and the like. As aromatic hydrocarbons, dodecylbenzene, biphenyl, ethylbiphenyl, 4-benzylbenzene, phenyltolylmethane, diphenylethane, 1,3-diphenylbenzene, dibenzyltoluene, methylnaphthalene, 2,7-diisopropylnaphthalene, methyl Examples include tetralin and naphthylphenylmethane.

The halogenated hydrocarbons include 1-bromodecane, 1-bromoundecane, 1-bromododecane, 1-bromotridecane, 1-bromotetradecane,
1-chlorotetradecane, 1-bromopentadecane, 1
-Bromohexadecane, 1-chlorohexadecane, 1-
Examples thereof include iodohexadecane, 1-bromoheptadecane, 1-bromooctadecane, 1-chlorooctadecane, 1-iodooctadecane, 1-bromoeicosane, 1-chloroeicosane, 1-bromodocosan, and 1-chlorodocosane. The compounds selected from the above-mentioned chain hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and halogenated hydrocarbons have a desensitizing property to the color development due to the reaction between the components (a) and (b). It is small and works effectively for heat coloring.

As the sulfides, di-n-octyl sulfide, di-n-nonyl sulfide, di-n-decyl sulfide, di-n-dodecyl sulfide, di-n-
Tetradecyl sulfide, di-n-hexadecyl sulfide, di-n-octadecyl sulfide, octyldodecyl sulfide, diphenyl sulfide, dibenzyl sulfide, ditolyl sulfide, diethyl phenyl sulfide, dinaphthyl sulfide, 4,4'-dichloro-
Examples thereof include diphenyl sulfide and 2,4,5,4'-tetrachloro-diphenyl sulfide.

As the ethers, aliphatic ethers having a total carbon number of 10 or more, for example, dipentyl ether, dihexyl ether, diheptyl ether, dioctyl ether, dinonyl ether, didecyl ether, diundecyl ether, didodecyl ether, Ditridecyl ether, ditetradecyl ether, dipentadecyl ether, dihexadecyl ether, dioctadecyl ether, decanediol dimethyl ether, undecanediol dimethyl ether, dodecanediol dimethyl ether, tridecanediol dimethyl ether, decanediol diethyl ether, undecanediol diethyl ether, etc. . Alicyclic ethers such as s-trioxane; As aromatic ethers, phenyl ether, benzyl phenyl ether, dibenzyl ether, di-p
-Tolyl ether, 1-methoxynaphthalene, 3,4
Examples thereof include 5-trimethoxytoluene.

The ketones include aliphatic ketones having a total carbon number of 10 or more, for example, 2-decanone, 3-decanone, 4-decanone, 2-undecanone, 3-undecanone, 4-undecanone, 5-undecanone, 6-undecanone, 2-dodecanone, 3-dodecanone, 4-dodecanone, 5-dodecanone, 2-tridecanone, 3-tridecanone, 2-tetradecanone, 2-pentadecanone, 8
Pentadecanone, 2-hexadecanone, 3-hexadecanone, 9-heptadecanone, 2-pentadecanone,
-Octadecanone, 2-nonadecanone, 10-nonadacanone, 2-eicosanone, 11-eicosanone, 2-heneicosanone, 2-docosanone, lauron, stearone and the like. Arylalkyl ketones having a total carbon number of 12 to 24, for example, n-octadecanophenone, n-heptadecanophenone, n-hexadecanophenone, n-pentadecanophenone, n-tetradecanophenone; 4-n-
Dodecaacetophenone, n-tridecanophenone, 4-
n-undecanoacetophenone, n-laurophenone,
4-n-decanoacetophenone, n-undecanophenone, 4-n-nonylacetophenone, n-decanophenone, 4-n-octylacetophenone, n-nonanophenone, 4-n-heptylacetophenone, n-octanophenone, 4 -N-hexylacetophenone, 4-n-
Cyclohexyl acetophenone, 4-tert-butyl propiophenone, n-heptaphenone, 4-n-pentyl acetophenone, cyclohexyl phenyl ketone,
Benzyl-n-butyl ketone, 4-n-butylacetophenone, n-hexanophenone, 4-isobutylacetophenone, 1-acetonaphthone, 2-acetonaphthone,
Cyclopentyl phenyl ketone and the like. Aryl aryl ketones, for example, benzophenone, benzyl phenyl ketone, dibenzyl ketone and the like. Alicyclic ketones, for example, cyclooctanone, cyclododecanone, cyclopentadecanone, 4-tert-butylcyclohexanone and the like can be exemplified.

As the esters, esters having 10 or more carbon atoms are effective, and include monohydric carboxylic acids having aliphatic and alicyclic or aromatic rings and monohydric alcohols having aliphatic and alicyclic or aromatic rings. Esters and aliphatics obtained from any combination of esters, aliphatic and alicyclic or aromatic polyhydric carboxylic acids and aliphatic and alicyclic or aromatic monohydric alcohols obtained from any combination And esters obtained from any combination of a monovalent carboxylic acid having an alicyclic or aromatic ring and a polyhydric alcohol having an aliphatic and an alicyclic or aromatic ring, and specifically, ethyl caprylate and caprylic acid. Octyl, stearyl caprylate, myristyl caprate,
Stearyl caprate, docosyl caprate, 2-ethylhexyl laurate, n-decyl laurate, 3-methylbutyl myristate, cetyl myristate, isopropyl palmitate, neopentyl palmitate, nonyl palmitate, cyclohexyl palmitate, n-stearate Butyl, 2-methylbutyl stearate, 3,5,5-trimethylhexyl stearate, n-undecyl stearate, pentadecyl stearate, stearyl stearate, cyclohexyl methyl stearate, isopropyl behenate, hexyl behenate, lauryl behenate, Behenyl behenate, cetyl benzoate, p-
tert-butyl stearyl benzoate, dimyristyl phthalate, distearyl phthalate, dimyristyl oxalate, dicetyl oxalate, dicetyl malonate, dilauryl succinate, dilauryl glutarate, diundecyl adipate, dilauryl azelate, di-lauryl sebacate (n −
Nonyl), dineopentyl 1,18-octadecylmethylenedicarboxylate, ethylene glycol dimyristate, propylene glycol dilaurate, propylene glycol distearate, hexylene glycol dipalmitate, 1,5-pentanediol dimyristate,
1,2,6-hexanetriol trimiristate,
Examples thereof include 1,4-cyclohexanediol didecyl, 1,4-cyclohexane dimethanol dimyristate, xylene glycol dicaprinate, and xylene glycol distearate.

An ester of a saturated fatty acid and a branched aliphatic alcohol; an unsaturated fatty acid or an ester of a branched or substituted saturated fatty acid or an aliphatic alcohol having 16 or more carbon atoms; cetyl butyrate; Ester compounds selected from stearyl butyrate and behenyl butyrate are also effective. Specifically, 2-ethylhexyl butyrate, 2-ethylhexyl behenate, 2-ethylhexyl myristate, 2-ethylhexyl caprate, lauric acid 3,
5,5-trimethylhexyl, palmitic acid 3,5,5
-Trimethylhexyl, 3,5,5-trimethylhexyl stearate, 2-methylbutyl caproate, 2-methylbutyl caprylate, 2-methylbutyl caprate,
1-ethylpropyl palmitate, 1-ethylpropyl stearate, 1-ethylpropyl behenate, 1-ethylhexyl laurate, 1-ethylhexyl myristate, 1-ethylhexyl palmitate, 2-caproic acid
Methylpentyl, 2-methylpentyl caprylate, 2-methylpentyl caprate, 2-methylpentyl laurate, 2-methylbutyl stearate, 2 stearic acid
-Methylbutyl, 3-methylbutyl stearate, 1-methylheptyl stearate, 2-methylbutyl behenate, 3-methylbutyl behenate, 1-methylheptyl stearate, 1-methylheptyl behenate, 1-ethylpentyl caproate, palmitin 1-ethylpentyl acid, 1-methylpropyl stearate, 1 stearic acid
-Methyloctyl, 1-methylhexyl stearate,
1,1-dimethylpropyl laurate, 1-capric acid
Methylpentyl, 2-methylhexyl palmitate, 2-methylhexyl stearate, 2-methylhexyl behenate, 3,7-dimethyloctyl laurate, 3,7-dimethyloctyl myristate, 3,7 palmitate
-Dimethyloctyl, 3,7-dimethyloctyl stearate, 3,7-dimethyloctyl behenate, stearyl oleate, behenyl oleate, stearyl linoleate, behenyl linoleate, 3,7-dimethyloctyl erucate, stearyl erucate Isostearyl erucate, cetyl isostearate, stearyl isostearate, 2-methylpentyl 12-hydroxystearate, 2-ethylhexyl 18-bromostearate, 2
-Isostearyl ketomyristate, 2-ethylhexyl 2-fluoromyristate, cetyl butyrate, stearyl butyrate, behenyl butyrate and the like.

Further, carboxylic acid ester compounds disclosed in Japanese Patent Publication No. 4-17154, for example, a carboxylic acid ester having a substituted aromatic ring in the molecule, a carboxylic acid having an unsubstituted aromatic ring in the molecule and a carboxylic acid having 10 or more carbon atoms. Esters of aliphatic alcohols, carboxylic acid esters containing a cyclohexyl group in the molecule, esters of fatty acids having 6 or more carbon atoms and unsubstituted aromatic alcohols or phenols, fatty acids having 8 or more carbon atoms and branched aliphatic alcohols or esters, dicarboxylic acids Esters of acids and aromatic or branched aliphatic alcohols, dibenzyl cinnamate, heptyl stearate, didecyl adipate, dilauryl adipate, dimyristyl adipate, dicetyl adipate, distearyl adipate, trilaurin, trimyristin, tristearin , Dimyristin, Stearic and the like.

A fatty acid ester compound obtained from an odd aliphatic monohydric alcohol having 9 or more carbon atoms and an aliphatic carboxylic acid having an even carbon number, n-pentyl alcohol or n-heptyl alcohol, and an even aliphatic compound having 10 to 16 carbon atoms. Fatty acid ester compounds having a total of 17 to 23 carbon atoms obtained from aliphatic carboxylic acids are also effective. Specifically, n-pentadecyl acetate, n-tridecyl butyrate, n-pentadecyl butyrate, n-undecyl caproate, n-tridecyl caproate, n-pentadecyl caproate, n-nonyl caprylate, n-undecyl caprylate, N-tridecyl caprylate, n-pentadecyl caprylate, n-caprate
Heptyl, n-nonyl caprate, n-undecyl caprate, n-tridecyl caprate, n-pentadecyl caprate, n-pentyl laurate, n-laurate
Heptyl, n-nonyl laurate, n-undecyl laurate, n-tridecyl laurate, n-pentadecyl laurate, n-pentyl myristate, n-heptyl myristate, n-nonyl myristate, n-undecyl myristate, N-tridecyl myristate, n-pentadecyl myristate, n-pentyl palmitate,
N-heptyl palmitate, n-nonyl palmitate,
N-undecyl palmitate, n-tridecyl palmitate, n-pentadecyl palmitate, n-stearate
-Nonyl, n-undecyl stearate, n-tridecyl stearate, n-pentadecyl stearate, n-nonyl eicosanoate, n-undersi eicosanoate, n-tridecyl eicosanoate, n-pentadecyl eicosanoate, n-nonyl behenate , N-undecyl behenate,
Examples include n-tridecyl behenate and n-pentadecyl behenate.

Examples of the alcohols include saturated aliphatic monohydric alcohols such as decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, heptadecyl alcohol, and octadecyl alcohol. , Eicosyl alcohol,
Docosyl alcohol and the like. Aliphatic unsaturated alcohols such as allyl alcohol and oleyl alcohol; Cycloaliphatic alcohols, for example, cyclopentanol, cyclohexanol, cyclooctanol, cyclododecanol,
4-tert-butylcyclohexanol and the like. Aromatic alcohols, for example, 4-methylbenzyl alcohol, benzhydrol and the like. Polyhydric alcohols, such as polyethylene glycol, can be exemplified.

Examples of the acid amides include the following compounds. Acetamide, propionamide, butyric amide, caproic amide, caprylic amide, capric amide, lauric amide, myristic amide,
Palmitic acid amide, stearic acid amide, behenic acid amide, oleic acid amide, erucic acid amide, benzamide, caproic anilide, caprylic anilide, capric anilide, lauric anilide, myristic anilide, palmitic anilide, stearic anilide,
Behenic acid anilide, oleic acid anilide, erucic acid anilide, caproic acid N-methylamide, caprylic acid N-
Methylamide, capric acid N-methylamide, lauric acid N-methylamide, myristic acid N-methylamide,
Palmitic acid N-methylamide, stearic acid N-methylamide, behenic acid N-methylamide, oleic acid N-
Methylamide, erucic acid N-methylamide, lauric acid N-ethylamide, myristic acid N-ethylamide, palmitic acid N-ethylamide, stearic acid N-ethylamide, oleic acid N-ethylamide, lauric acid N-
Butylamide, N-butylamide myristic acid, N-butylamide palmitic acid, N-butylamide stearate, N-butylamide oleate, N-octylamide laurate, N-octylamide myristic acid, N-octylamide palmitate, N-stearic acid -Octylamide, oleic acid N-octylamide, lauric acid N
-Dodecylamide, myristic acid N-dodecylamide,
Palmitic acid N-dodecylamide, stearic acid N-dodecylamide, oleic acid N-dodecylamide, dilauric acid amide, dimyristic acid amide, dipalmitic acid amide, distearic acid amide, dioleic acid amide,
Trilauric amide, Trimyristic amide, Tripalmitic amide, Tristearic acid amide, Trioleic amide, Succinamide, Adipamide,
Glutaramide, malonamide, azelaic amide, maleic amide, succinic N-methylamide, adipic N-methylamide, glutaric N-methylamide, malonic N-methylamide, azelaic N-methylamide, succinic N- Ethylamide, adipic acid N-
Ethylamide, glutaric acid N-ethylamide, malonic acid N-ethylamide, azelaic acid N-ethylamide, succinic acid N-butylamide, adipic acid N-butylamide, glutaric acid N-butylamide, malonic acid N-butylamide, adipic acid N-octylamide , Adipic acid N
-Dodecylamide and the like.

Examples of the waxes and medium molecular weight polymers include paraffin wax having a melting point of 50 to 120 ° C., microcrystalline wax, petrolactam, oxidized paraffin wax, and petrolactam oxide. Shellac, sugar cane wax, carnauba wax, candelilla wax,
Castor wax, hardened tallow oil, hardened fish oil, hardened rapeseed oil, montan wax, palm wax, chuhokuro, hazelou, wool fat, etc. Polyethylene wax, montanic acid wax, ethylene-vinyl acetate copolymer wax, ethylene acrylic copolymer wax, vinyl ether wax, etc.
Examples include palm oil, babassu oil, liquid paraffin, polybutene, polybutadiene, polystyrene oligomer, and the like.

The composition of the present invention comprises the above (a), (b),
The component (C) is an essential component, and the proportion of each component depends on the concentration, the color change temperature, the color change form, and the type of each component. (B) component 0.1 to 50, preferably 0.5 to 2
0, component (c) is in the range of 1 to 200, preferably 5 to 100 (all the above parts are parts by weight).

The color change characteristics of the reversible thermochromic composition comprising a mixture of the components (a), (b) and (c) will be described with reference to a graph showing a color density-temperature curve in FIG. In FIG. 1, the vertical axis represents color density, and the horizontal axis represents temperature. The change in the color density due to the temperature change proceeds along the arrow. Here, temperature T ₁ of the color start temperature of the reversible thermochromic composition, T ₂ is complete coloring temperature, T ₃ decolorization initiation temperature, T ₄ indicates a complete decoloring temperature. The hysteresis width ΔH is calculated from the following equation as the temperature difference between the path from the decolored state to the colored state and the path from the decolored state to the colored state. _{ΔH = (T 2 -T 1)} / 2 - (T 3 -T 4) / 2 Therefore, the composition for forming a colorless state by T ₁ following temperature than the temperature of T ₁ in the heating process, and color Beginning, T
Upon reaching the _second temperature becomes full colored state, the composition was heated to a temperature exceeding T ₂ are, T ₃ in the process of cooling
The beginning decolored to reach temperature, thinner color density when further cooled, completely decolorized when it reaches the temperature of T _4. Composition was cooled to below the temperature T ₄ is reversibly to reproduce the discolouration behavior.

Thus, the discoloration behavior of the reversible thermochromic composition of the present invention (illustrated in FIGS. 1 and 2) is different from that of the conventional heat-decolorable reversible thermochromic composition (FIG. 3). On the other hand, it shows the reverse discoloration behavior.

Although the reversible thermochromic composition of the present invention is effective when used as it is, it is preferable to use it in a microcapsule. It consists of acidic substances, basic substances,
Even if it comes in contact with chemically active substances such as peroxides or other solvent components, it does not lower its function, of course, it can maintain heat stability, and it is reversible under various use conditions. The thermochromic composition is kept at the same composition,
This is because the same operation and effect can be achieved. The microcapsule pigment containing the reversible thermochromic composition has a particle size of 0.1 to 100 μm, preferably 3 to 30 μm.
The range of m satisfies the practicality. The microencapsulation is carried out by a conventionally known interfacial polymerization method, in situ polymerization method, in-liquid curing coating method, phase separation method from aqueous solution, phase separation method from organic solvent, melting dispersion cooling method, air suspension. There are a coating method, a spray drying method, and the like, which are appropriately selected according to the application. Furthermore, on the surface of the microcapsule, a secondary resin film is further provided according to the purpose to impart durability,
The surface properties can be modified for practical use.

Each of the components (a), (b) and (c) may be a mixture of two or more compounds, and a light stabilizer may be added as long as the function is not hindered. Can be. Examples of the light stabilizer include an ultraviolet absorber, a visible light absorber, an infrared absorber, an antioxidant, a carotene, a dye, an amine, which prevent light deterioration caused by an excited state due to a photoreaction of the component (a). Compounds that suppress the oxidation reaction, such as singlet oxygen quenchers such as phenols, nickel complexes, and sulfides, superoxide anion quenchers such as complexes of oxide dismutase and cobalt, and nickel, and ozone quenchers. , 0.3 to 24% by weight,
Preferably, it is blended in the system at a ratio of 0.8 to 16% by weight. Among them, the ultraviolet absorber, an antioxidant and / or
Alternatively, a system using a singlet oxygen quencher is particularly effective for improving light resistance. Further, an anti-aging agent, an antistatic agent, a polarity-imparting agent, a thixotropic agent, an antifoaming agent and the like can be added as required to improve the function. Further, the above-described conventional reversible thermochromic composition may be blended in an appropriate ratio, or a general dye / pigment (non-thermochromic) may be blended.

The reversible thermochromic composition or the microcapsule pigment containing the same is dispersed in a medium containing a binder which is a film-forming material and applied as a reversible thermochromic material such as ink or paint. More known methods, for example, screen printing, offset printing, gravure printing, coater, printing means such as tampo printing, transfer, brush coating, spray coating, electrostatic coating, electrodeposition coating, flow coating, roller coating, dip coating, Paper, synthetic paper,
Cloth, flocking or brushed cloth, non-woven fabric, synthetic leather, leather,
A reversible thermochromic layer can be formed on a support such as plastic, glass, porcelain, wood, and stone, or can be dispersed in the support. Further, in the form of a microcapsule pigment, it can be applied as a material that is kneaded and integrated into a thermoplastic resin in a molten state.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (A) and (B) of the reversible thermochromic composition of the present invention (Examples 1 to 20) and the microcapsule pigments of the reversible thermochromic composition of the present invention (Examples 21 to 28) ,
The composition of the component (c) is shown in Tables 1 and 3, respectively. The reversible thermochromic composition of the present invention (Examples 1 to 20) and the microcapsule pigment of the reversible thermochromic composition of the present invention (Example 21)
To 28), a color development start temperature (T ₁ ), a complete color development temperature (T ₂ ), a decolorization start temperature (T ₃ ), a complete decoloration temperature (T
₄ ) and the hysteresis width (ΔH) are shown in Tables 2 and 4 respectively.
Shown in Graphs showing temperature-color density curves of Example 21 and Example 4 are shown in FIGS. 1 and 2, respectively. The present invention is not limited to the embodiments. The numbers in parentheses in the table indicate parts by weight, and the numbers indicating the following amounts are all parts by weight.

[Table 1]

[Table 2]

[Table 3]

[Table 4] Table 5 shows the melting point and cloud point of the alkoxyphenol compound represented by the general formula (1) used as the component (b) of the reversible thermochromic composition of the present invention.

[Table 5] Measurement Sample The discoloration characteristics of the reversible thermochromic compositions of Examples 1 to 20 were as follows. A methyl ethyl ketone solution having a concentration of 30% by weight of the total of the components (a), (b) and (c) was prepared, and a filter paper (Toyo) No. 2 filter paper (manufactured by Filter Paper Co., Ltd.) was impregnated, and the composition obtained by evaporating methyl ethyl ketone was heated to develop a color.
The sample left at room temperature was used as a measurement sample. Example 2
The color change characteristics of the microcapsule pigments of the reversible thermochromic compositions of Nos. 1 to 28 were determined by screen printing using a reversible thermochromic ink obtained by dispersing 40 parts of the microcapsule pigment in an ethylene-vinyl acetate emulsion. Was used as a measurement sample. Measurement method The above-mentioned measurement sample was measured using a colorimeter [TC-3600 type colorimeter,
(Manufactured by Tokyo Denshoku Co., Ltd.), heated and cooled at a temperature range of 60 ° C. at a rate of 10 ° C./min, and the lightness value indicated by the color difference meter at each temperature was plotted on a graph.

The method for preparing the microcapsule pigment of the reversible thermochromic composition of Example 21 and the change in color density of the printed matter printed with the microcapsule pigment due to the temperature change will be described below. [The microcapsule pigments of the reversible thermochromic compositions of Examples 22 to 28 were prepared in the same manner as in Example 21 except that the compositions of the components (a), (b), and (c) were changed as shown in Table 3. Prepared. Example 21 3- [2-ethoxy-4- (N-ethylanilino) phenyl] -3- (1-ethyl-2-methylindole-3
-Yl) -4-azaphthalide (1.0 part by weight), p-n-octyloxyphenol (10.0 parts by weight), and n-docosane (20.0 parts by weight) were heated and melted at 120 ° C to obtain an epoxy resin. A reversible thermochromic microcapsule pigment in the form of microcapsules encapsulated in an epoxy resin film by an interfacial polymerization reaction with a resin and an amine curing agent was obtained. Using a reversible thermochromic ink obtained by dispersing 40 parts by weight of the reversible thermochromic microcapsule pigment in an ethylene-vinyl acetate emulsion, printing was performed on high quality paper by screen printing. The printed matter has a color development start temperature T _14.
It shows a blue color at 1 ° C. and a full color development temperature T ₂ 55 ° C., and decolors at a decolorization start temperature T ₃ 36 ° C. and a complete decolorization temperature T ₄ 32 ° C. The hysteresis width ΔH is 14.0 ° C.

Application Example 1 43.0 parts by weight of a microcapsule pigment containing the reversible thermochromic composition prepared in Example 22, 2.0 parts by weight of a fluorescent pigment (pink), an ethylene-vinyl acetate copolymer resin emulsion 50.0 parts by weight, 3.0 parts by weight of an antifoaming agent, 1.0 part by weight of a thickener (sodium alginate), 3.0 parts by weight of a leveling agent, and 1.0 part by weight of a preservative uniformly in a vehicle. After mixing, a reversible thermochromic screen ink was obtained. A reversible thermochromic sheet is formed by printing using the screen ink on a support obtained by coating an adhesive on 80 μm thick white synthetic paper and laminating a 1 mm-thick polyethylene foam to form a reversible thermochromic sheet. Obtained. The reversible thermochromic sheet exhibits a purple color when heated to 25 ° C. or higher, and a pink color when the temperature is lower than 17 ° C.

Application Example 2 44.0 parts by weight of the microcapsule pigment containing the reversible thermochromic composition prepared in Example 24 was uniformly dispersed in 56.0 parts by weight of an aqueous vehicle containing a shear thinning agent. By mixing, an ink for a reversible thermochromic aqueous ballpoint pen was prepared. When writing was performed on report paper using a ballpoint pen filled with the ballpoint pen ink, black handwriting with a good writing start was obtained. In addition, as a result of testing the thermal discoloration of the handwriting, it becomes black when heated above 20 ° C, and becomes colorless when heated below 8 ° C.

Application Example 3 43.3 parts by weight of a microcapsule pigment containing the reversible thermochromic composition prepared in Example 21, 56.4 parts by weight of a hard type liquid epoxy resin, 0.3 parts by weight of an antifoaming agent Was uniformly dispersed and kneaded, and 35.0 parts by weight of a room temperature-curable aliphatic polyamine was added to the reversible thermochromic epoxy ink obtained, followed by stirring and mixing to obtain a reversible thermochromic epoxy ink. The epoxy ink was subjected to curved screen printing on the surface of a ceramic cup using a stainless steel 100 mesh screen plate, and cured by heating at 70 ° C. for 60 minutes to form a reversible thermochromic layer. The thermochromic layer exhibits a blue color when heated to 41 ° C. or higher, and becomes colorless at a temperature lower than 32 ° C.

Application Example 4 15.0 parts by weight of a microcapsule pigment containing the reversible thermochromic composition prepared in Example 22, 1.0 part by weight of a fluorescent pigment (pink), 40% acrylic resin / xylene solution 40 A reversible thermochromic spray paint was obtained by stirring and mixing in a vehicle comprising 0.0 parts by weight, 20.0 parts by weight of xylene, 20.0 parts by weight of methyl isobutyl ketone, and 6.0 parts by weight of a polyisocyanate-based curing agent. The reversible thermochromic spray paint was applied to the entire body of a car-shaped miniature car by spray coating and dried to obtain a reversible thermochromic miniature car. The thermochromic layer turns purple when heated to 25 ° C. or higher, and turns pink when the temperature is lower than 17 ° C.

Application Example 5 30.0 parts by weight of the microcapsule pigment containing the reversible thermochromic composition prepared in Example 23 was mixed with 45.0 parts by weight of an acrylate resin emulsion and 1.0 part by weight of an antifoaming agent. The dispersion was uniformly dispersed in a vehicle consisting of 22.5 parts by weight of dilution water and filtered through a 180-mesh stainless steel screen to obtain a reversible thermochromic aqueous spray paint.
Next, the water-based spray paint was applied to a white lace fabric, and then dried to form a reversible thermochromic layer, thereby obtaining a reversible thermochromic fabric. The cloth was sewn to produce a reversible thermochromic doll dress. It should be noted that the doll dress becomes orange when heated to 21 ° C. or higher, and becomes colorless below 10 ° C.

APPLICATION EXAMPLE 6 50 parts by weight of the microcapsule pigment containing the reversible thermochromic composition prepared in Example 25 was added to 1000.0 parts by weight of a 12-nylon resin (melting point: 178 ° C.), UV absorber 1
0.0 part by weight, uniformly dispersed with a Hensyl mixer, and then molded using an extruder to obtain a reversible thermochromic 1
A 2-nylon resin pellet was obtained. Melt spinning was performed with the molding resin composition to obtain a reversible thermochromic filament.
Hair was implanted on the head of the doll using the filament.
The reversible thermochromic filament exhibits a pink color when heated to 21 ° C. or higher, and becomes colorless at a temperature lower than 9 ° C.

[0034]

The reversible thermochromic composition of the present invention exhibits a color-developed state by heating from a decolored state and exhibits a reversible color-change behavior of returning to a decolored state by cooling from the color-developed state. Heat discoloration type heat discoloration material that discolors in the living temperature range of the above shows reverse discoloration behavior, applied to various fields such as temperature indicating material, temperature detection material, forgery prevention, training element, toy, decoration, etc. Satisfies practicality as a new thermochromic material.
Particularly in the toy field, the reversible discoloration effect of color development / decoloration can be exhibited by thermal means in the living temperature range such as hot water, cold water, body temperature, etc. Can be satisfied, and can contribute to enhancing the marketability. Furthermore, the change can be diversified by using in combination with a conventional heat-decolorable thermochromic composition.

[Brief description of the drawings]

FIG. 1 shows the temperature of one embodiment of the reversible thermochromic composition of the present invention.
4 is a graph showing a color density curve.

FIG. 2 is a graph showing a temperature-color density curve of another example of the reversible thermochromic composition of the present invention.

FIG. 3 is a schematic diagram of a temperature-color density curve of a conventional heat-decolorable reversible thermochromic composition.

[Explanation of symbols]

T ₁ coloring initiation temperature T ₂ complete coloring temperature T ₃ decoloring starting temperature T ₄ complete decoloring temperature

Claims (5)

[Claims] (1) an electron-donating color-forming organic compound,
(B) at least one kind of electron-accepting compound selected from the alkoxyphenol compounds represented by the following general formula (1): (c) a reaction medium for reversibly generating the electron transfer reaction according to the above (a) and (b) A reversible thermochromic composition having a reversible color-changing function of exhibiting a color-developed state by heating from a decolored state and exhibiting a decolored state by cooling from the color-developed state, comprising a compound as an essential component. Embedded image (R represents an alkyl group.) 2. The reversible thermochromic composition according to claim 1, wherein the alkyl group of the alkoxyphenol compound represented by the general formula (1) is a linear alkyl group having 3 to 18 carbon atoms. 3. The reversible heat according to claim 1, wherein the component (c) is a compound selected from chain hydrocarbons, alicyclic hydrocarbons, aromatic hydrocarbons, and halogenated hydrocarbons. Discolorable composition. 4. The method according to claim 1, which is encapsulated in a microcapsule.
4. The reversible thermochromic composition according to any one of claims 1 to 3. 5. The reversible thermochromic composition according to claim 1, wherein the heating temperature is not higher than 90 ° C.