JP2000072972A - Reversible thermochromic molding resin composition and molded product using same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide reversible thermochromic molding resin compositions such as resin pellets capable of presenting a colored state from a non-colored state by heating, and molded products obtained by molding said compositions. SOLUTION: Reversible thermochromic molding resin compositions comprise (A) an electron-donating color-developing organic compound, (B) at least one electron-accepting compound selected from an alkoxyphenol compound represented by the formula (wherein R is alkyl), (C) a micro-capsulated pigment containing a reversible thermochromic composition composed of a compound of a reaction medium which reversibly causes the electron donating and accepting reactions by said components (A) and (B), and a molding resin. Molded products use these compositions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a reversible thermochromic molding resin composition and a molded article using the same. More specifically, a reversible color change function that exhibits a colored state by heating from the decolored state and exhibits a decolored state by lowering the temperature from the colored state, or a temperature rise caused by heating from the decolored state as a trigger, The resin composition for reversible thermochromic molding having a reversible color-changing function of starting color development in the subsequent temperature-reducing process, developing a color-developed state with the maximum color-developing density, and returning to the decolored state, and a molded article using the same About.

[0002]

2. Description of the Related Art Heretofore, (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound (c) the (a)
A reversible thermochromic composition comprising a compound which is a reaction medium for reversibly causing the electron transfer reaction according to (b) and a molding resin composition comprising a molding resin are disclosed (JP-A-49-99141). JP-A-50-107040, JP-A-60-173028, JP-A-3-2
No. 90467). The above-mentioned conventional molding resin composition starts decoloring in the process of raising the temperature from the color-developed state, exhibits a completely decolored state at a specific temperature or higher, starts color development in the subsequent temperature-lowering process, and returns to the color-developed state. Mainly those having a function of exhibiting reversible thermochromicity (see FIG. 3) are formed into various shapes and applied to the field of temperature indicator and toys. Also, some proposals of a heating and coloring type have been disclosed regarding a reversible thermosensitive recording material in the field of thermosensitive recording materials (Japanese Patent Laid-Open No. 5-1).
24360, JP-A-6-210954),
Since these reversible thermosensitive recording materials are configured so that the thermal head of the thermal printing device is maintained at a temperature exceeding one hundred and several tens of degrees, and a color developing state can be developed by applying the same,
In the temperature range of living environment, effective discoloration behavior cannot be exhibited, and its applicability to various uses is restricted.

[0003]

The present inventors have further studied the resin composition for reversible thermochromic molding, and found that (a) an electron-donating color-forming organic compound and (b) an electron-accepting compound. (C) a reversible thermochromic microcapsule pigment enclosing a reversible thermochromic composition comprising a compound as a reaction medium for reversibly causing the electron transfer reaction according to (a) and (b) above, and a molding resin By applying a specific alkoxyphenol compound to the component (b) in the reversible thermochromic molding resin composition consisting of: Shows the discoloration behavior of returning to the decolored state by the temperature drop, and the color change behavior of returning to the decolored state after developing the color development state with the maximum color density in the temperature drop process after heating, triggered by the temperature rise by heating Show Form resin composition can be obtained,
The present invention has been completed by finding that molded articles of various shapes molded with the molding resin composition can impart a new discoloring effect not only to temperature indicating materials but also toy fields, decoration fields, design fields, and the like.

[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 microcapsule pigment enclosing a reversible thermochromic composition comprising a compound that is a reaction medium for reversibly causing an electron transfer reaction by the above, and a reversible thermochromic molding resin composition containing a molding resin.

Embedded image (R represents an alkyl group.) Further, the molding resin is a thermoplastic resin, a molded article molded from the reversible thermochromic molding resin composition, and a filament or filament. It must be in the form of a film.

The above-mentioned (a) electron-donating color-forming organic compounds include diphenylmethanephthalides known in the art,
Phenyl indolyl phthalides, indolyl phthalides, diphenylmethane azaphthalides, phenyl indolyl azaphthalides, fluorans, styrinoquinolines, diaza rhodamine lactones, pyridines, quinazolines, bisquinazolines, etc. These compounds are exemplified below. 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-methylindol-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-Np-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. 2,6-diphenyl-4- (4'-dimethylaminophenyl) -pyridine 2,6-diethoxy-4- (4'-diethylphenyl)
-Pyridine 2- (2'-octoxyphenyl) -4- (4'-dimethylaminophenyl) -6-phenyl-pyridine 4- (4-methoxyphenyl) -2,6-bis (-dimethylaminophenyl)- Pyridine 2,4,6-tris (4-dimethylaminophenyl)-
Pyridine 2- (4'-dimethylaminophenyl) -4- (4 ''
-Nitrophenyloxy) -quinazoline 2- (4'-diethylaminophenyl) -4-phenyl-quinazoline 4,4 '-(ethylenedioxy) -bis [2- (4-diethylaminophenyl) quinazoline] And a diazarhodamine lactone-based compound that is effective for expressing the pink color of the above.

According to the present invention, in a composition comprising (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a specific alkoxyphenol as the component (b), By dispersing a microcapsule pigment containing a reversible thermochromic composition composed of a compound in a molding resin, generally in a living environment temperature range, in a heating process from a decolored state, a colored state is exhibited, and the colored state is obtained. , A reversible thermochromic molding resin composition exhibiting a decolored state in the process of cooling from the resin 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 preferably has 3 to 18 carbon atoms.
This is because a system having an alkyl group having less than 3 or more than 18 carbon atoms does not satisfy practicality because of low color density. Further, the alkyl group may be either a straight-chain or a side-chain alkyl group, but in consideration of more practical performance such as discoloration characteristics and coloring density, a straight-chain alkyl group is suitable, and preferably has 8 carbon atoms. To 12 straight-chain alkyl groups, more preferably a straight-chain alkyl group having 6 to 12 carbon atoms.

The following are examples of alkoxyphenol compounds. p-n-propyloxyphenol, p-n-butyloxyphenol, p-n-pentyloxyphenol, p-n-hexyloxyphenol, p-n-heptyloxyphenol, p-n-octyloxyphenol, p- n-nonyloxyphenol, pn-decyloxyphenol, pn-undecyloxyphenol, pn-dodecyloxyphenol, pn-
Tridecyloxyphenol, pn-tetradecyloxyphenol, pn-pentyldecyloxyphenol, pn-hexyldecyloxyphenol, p-
n-heptyldecyloxyphenol, pn-octyldecyloxyphenol, p-isopropyloxyphenol, p-1-methylpropyloxyphenol,
p-3-methylbutyloxyphenol, p-2-methylpentyloxyphenol, p-1-ethylpentyloxyphenol, p-1-ethylhexyloxyphenol, p-3,5,5-trimethylhexyloxyphenol, p- 3,7-dimethyloctyloxyphenol, p-1-ethylpropyloxyphenol, p-
Examples thereof include 2-methylhexyloxyphenol, p-1-methylheptyloxyphenol, and p-1-methyloctyloxyphenol.

The composition of 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), 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. Said (a),
(B) Reversibly causing the electron transfer reaction in (b) in a specific temperature range. (C) Compounds effective as a reaction medium 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.

Examples of the halogenated hydrocarbon 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 functions effectively when used in a reversible thermochromic composition having a reversible color-changing function, which is small and exhibits a color-developed state by heating from a decolored state and exhibits a decolored state by cooling from the color-developed state.

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.

Examples of the ethers include aliphatic ethers having 10 or more carbon atoms, 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.

Examples of 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. Arylalkyl ketones such as benzophenone, benzylphenyl 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. Monoesters having an aliphatic and alicyclic or aromatic ring and monohydric alcohols having an aliphatic and alicyclic or aromatic ring are useful. 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, cyclohexylmethyl 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.

Esters of saturated fatty acids and branched aliphatic alcohols, unsaturated fatty acids or branched or substituted saturated fatty acids and esters of aliphatic alcohols 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.

As the acid amides, the following compounds can be exemplified. 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.

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 reversible thermochromic composition comprises (a)
The components (b) and (c) are essential components, and the ratio of each component is
Although it depends on the density, discoloration temperature, discoloration form and the type of each component, generally, the component ratio at which desired characteristics can be obtained is as follows: component (a), component (b) component 0.1 to 50; Preferably 0.5 to 20, (c) component 1 to 200, preferably 5 to
100, more preferably in the range of 20 to 50 (all the above parts are parts by weight). In addition, each of the above (a),
The components (b) and (c) may each be a mixture of two or more compounds.

The reversible thermochromic composition used in the present invention uses an alkoxyphenol compound represented by the general formula (1) as the component (b). At this time, there is a characteristic in which the discoloration behavior upon heating is influenced by the magnitude of the desensitization of the component (c). The color change state is exhibited by heating from the decolored state, and the color change state is exhibited by the temperature decrease from the color developed state. Color change function or reversible color change that triggers the temperature rise due to heating from the decolored state, starts color development in the cooling process after heating, develops the color development state with the maximum color density, and then returns to the decolored state Indicates one of the functions.

More specifically, a system having a reversible color change function, in which a colored state is exhibited by heating and a decolorized state is exhibited by lowering the temperature from the colored state, is that the alkoxyphenol compound (b) has a relatively high melting point. It has a low melting point, a small difference between the cloud point and the cloud point, and has good crystallinity. Therefore, during the heating process from the decolored state, the alkoxyphenol compound becomes a molten state or a dissolved state, and exchanges electrons with the component (a). It is presumed that the reaction causes a color-developed state, and in the process of cooling from the color-developed state, the alkoxyphenol compound crystallizes and separates from the component (a) to form a decolored state. The discoloration temperature of the reversible thermochromic composition is set by selecting an alkoxyphenol compound having a cloud point as the component (b). Door can be. It is also possible to adjust the discoloration temperature by lowering the melting point by using two or more alkoxyphenol compounds in combination. Therefore, there is a discoloration temperature range in a temperature range lower than the conventional reversible thermosensitive recording material, that is, a living environment temperature range of 90 ° C. or less,
The color change due to heat such as hot water, cold water, body temperature, etc. is possible, and it is easy to adjust the color development temperature and color erasure temperature. It is also possible to obtain a hysteresis characteristic in which the path from the decolored state to the colored state greatly differs from the path from the decolored state to the colored state. The color change characteristics of the reversible thermochromic composition obtained by homogeneously mixing (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 indicates the color development start temperature of the reversible thermochromic composition, T ₂ indicates the complete color development temperature, T ₃ indicates the decolorization start temperature, and T ₄ indicates the complete decolorization 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 shows a discoloration behavior opposite to that of the conventional reversible thermochromic composition (FIG. 3).

A reversible color change function in which the temperature rise by heating from the decolored state is used as a trigger to start color development in the course of temperature decrease after heating, develop a color development state of maximum color density, and then return to the decolored state. In the system having (b), the high crystallinity of the (b) component is related to the behavior due to the melting of the (c) component, which affects the electron transfer reaction between the (b) and (b) components, and It is presumed to exhibit discoloration behavior. To illustrate this point,
(A), (B), (C) in the compatibilizer of the component, (C)
By heating above the melting point of the component, the component becomes a solution state,
Since the (b) alkoxyphenol compound in the crystallized state is redissolved and the (a) component exists in an independent state,
It shows a decolored state, and in the process of cooling down from this state,
The component (c) gradually starts to coagulate, and the component (a) and the component (b) are ionized and combined to form a colored state. When the temperature is further lowered, crystallization of the component (b) starts, and the components (a) and (b)
It is presumed that the binding of the components was broken and the color began to be erased, and finally a colorless colorless state was exhibited. (A), (b),
(C) The color change characteristics of the reversible thermochromic composition in which the components are homogeneously mixed will be described with reference to a graph showing a color density-temperature curve in FIG. In FIG. 2, 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, the temperature T ₅ represents the complete melting temperature of the reversible thermochromic compositions, T ₁ denotes a coloring initiation temperature, T ₂ represents the complete coloring temperature, T ₄ indicates a complete decoloring temperature. Thus, compositions heated to temperatures above T _5, the color density begins to color to reach temperatures T ₁ during the process of cooling darker, becomes completely colored state at a temperature T _2, exhibits a maximum color density, further When the temperature drops, the color density decreases, and the temperature T ₄
When it reaches, it completely discolors. Composition was cooled to below the temperature T _4, by heating to a temperature exceeding T ₅ again reversibly to reproduce the discolouration behavior.

The reversible thermochromic composition is used by being encapsulated in microcapsules. Even if it comes into contact with a chemically active substance such as an acidic substance, a basic substance, or a peroxide or other solvent components, it does not lower its function, and of course, can maintain heat stability. This is because the reversible thermochromic compositions can be maintained under the same composition under various conditions of use and can exhibit the same effects.
The microcapsule pigment containing the reversible thermochromic composition has a particle diameter of 0.1 to 100 μm, preferably 3 to 30 μm.
The range of μm 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.

In the present invention, the microcapsule pigment is used by being dispersed in a molding resin. Examples of the molding resin include linear low-density polyethylene, low-density polyethylene, medium-high-density polyethylene, ultra-high-density polyethylene, chlorinated polyethylene, polypropylene, chlorinated polypropylene, polyisobutylene, polybutadiene, polymethylpentene, polystyrene, and polyethylene terephthalate. , Polybutylene terephthalate, polyvinyl acetate, vinyl chloride resin, chlorinated polyvinyl chloride, polyvinylidene chloride, acrylate resin, methacrylate ester resin, polyamide, copolymerized polyamide, polyamide imide, polyacetal, polyvinyl formal, polyvinyl butyral, Polyarylate, polyetherimide, polyetheretherketone, polycarbonate, polyphenylether, polyphenylenesulfide, polysa Hong, fluorine resin, an ionomer resin, an ethylene - propylene copolymer resins, ethylene - vinyl acetate copolymer resin, ethylene - vinyl alcohol copolymer resin,
Ethylene-acrylate copolymer resin, ethylene-
Methacrylic acid ester copolymer resin, ethylene-vinyl chloride copolymer resin, vinyl chloride-propylene copolymer resin, vinyl chloride-vinylidene chloride copolymer resin, styrene-butadiene copolymer resin, acrylonitrile-vinylidene chloride copolymer resin, acrylonitrile-styrene Copolymer resin,
Acrylonitrile-ethylene-styrene copolymer resin, acrylonitrile-butadiene-styrene copolymer resin, acrylonitrile-chlorinated polyethylene-styrene copolymer resin, acrylonitrile-acrylate-styrene copolymer resin, ethylene-vinyl acetate resin-vinyl chloride graft copolymer Polymerized resin, methyl methacrylate-butadiene-styrene copolymer resin, styrene-based thermoplastic elastomer, olefin-based plastic elastomer, urethane-based plastic elastomer, polyester-based plastic elastomer,
1,2-polybutadiene plastic elastomer, vinyl chloride plastic elastomer, petroleum hydrocarbon resin, cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, nitrocellulose, low molecular weight polyethylene, low molecular weight polypropylene,
Thermoplastic resins such as polybutene, coumarone-indene copolymer, and phenoxy plastic; Epoxy resin, xylene resin, toluene resin, guanamine resin, epoxy acrylate, phenol resin, unsaturated polyester resin,
Thermosetting resins such as furan resin, polyimide, poly (p-hydroxybenzoic acid), polyurethane, urea resin, melamine resin, and silicone resin are exemplified.

Furthermore, a layer containing a light stabilizer and / or a light-shielding pigment is laminated on the molded body to improve light resistance, or a top coat layer is provided to improve durability. You can also. Examples of the light shielding pigment include pigments such as metallic luster pigment, transparent titanium dioxide, transparent iron oxide, transparent cesium oxide, and transparent zinc oxide.

The fields to which the molded article is applied include clothing, toys, artificial flowers, stationery, daily necessities, kitchen utensils, makeup tools, sports equipment, indoor decorations, and the like.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION The resin composition for reversible thermochromic molding of the present invention is usually processed into the form of pellets, and films, sheets, plates, bars, rods, pipes, filaments and other various shapes are formed by various molding machines. Used for molding of shaped objects.
When a thermoplastic resin is used as the molding resin, the film can be formed by calendar roll processing or inflation processing. Further, a plate-like body, a rod-like body, a pipe, a filament and the like can be formed by an extruder. In addition, molded articles of various forms can be formed by injection molding, for example, toy shaped objects such as riding toys, dolls, living related goods, sports equipment, various indoor equipment items, and the like. It is also possible to form a part of the shaped object. Filament obtained by melt spinning etc.
It can be used not only for fabrics and knits, but also for flocking. In a system to which a thermosetting resin is applied, various moldings can be formed by filling a mold having a predetermined shape and size. The molded article shows the same reversible thermochromic property as the molding resin composition of the present invention.

[0030]

Examples The components (a), (b) and (c) of the reversible thermochromic composition (applied to Examples 1 to 9) used in the present invention and the proportions of the respective components are shown in the following table. The numbers in parentheses in the table indicate parts by weight, and the numbers indicating the following blending amounts are all parts by weight.

[0031]

[Table 1]

The methods for preparing the reversible thermochromic compositions of Examples 2 to 9 and the microcapsule pigments containing the same are the same as those described in Example 1.

Example 1 Preparation of a reversible thermochromic composition and a reversible thermochromic microcapsule pigment containing the above composition 3-[(2-ethoxy-4-N-ethylanilino) phenyl] -3- (1- Ethyl-2-methylindole-3
-Yl) -4-azaphthalide 1.5 parts by weight, pn-octyloxyphenol 5.0 parts by weight, pn-heptyloxyphenol 5.0 parts by weight, n-eicosane 3
0.0 parts by weight, 2- (3-t-butyl-5-methyl-2)
-Hydroxyphenyl) -5-chlorobenzotriazole was heated and dissolved at 120 ° C. at a temperature of 120 ° C. to obtain a reversible thermochromic composition, which was obtained as a homogeneous solution. (Epoxy resin) After mixing into a mixed solution of 10 parts by weight, this was mixed with a 10% gelatin solution 10
The mixture is dropped into 0 parts by weight, and stirred so as to be fine droplets. A solution prepared by dissolving 5.0 parts by weight of a curing agent Epicure U (available from Yuka Shell Epoxy Co., Ltd., an amine adduct of an epoxy resin) in 45.0 parts by weight of water was added to the stirring solution. The solution was gradually dropped, and stirring was continued for about 5 hours while maintaining the liquid temperature at 80 ° C. to obtain a microcapsule stock solution. The stock solution was centrifuged to obtain a reversible thermochromic microcapsule pigment. The reversible thermochromic microcapsule pigment is colorless at room temperature as shown in FIG. 1, but begins to develop color from around 28 ° C. when heating is started (T ₁ ) and changes to a colored state at 40 ° C. (T ₂₎ Next, when the cooling is started, the color-developing state is maintained up to 24 ° C. (T ₃ ), and the color is gradually erased by further cooling and completely discolored at 16 ° C. (T ₄ ). .

Preparation of Resin Composition for Reversible Thermochromic Molding 40.0 parts by weight of a microcapsule pigment containing the thermochromic composition 1 and 3.0 parts by weight of a fluorescent pink pigment, a low density polyethylene resin (melt flow rate) 1.3) 100
After mixing 0.0 parts by weight, 10.0 parts by weight of an ultraviolet absorber and 0.5 parts by weight of a metal soap lubricant and uniformly dispersing them with a tumbler mixer, the mixture is molded by using an extruder, and then reversibly thermochromic polyethylene. A resin pellet was obtained.

Using the reversible thermochromic molding resin composition, a goldfish-shaped reversible thermochromic blow molded article was obtained by blow molding using a goldfish mold. The blow molded article is pink in a room temperature environment as shown in FIG. 1, but exhibits a purple color when placed in warm water at 40 ° C., and is taken out of the warm water and immersed in water at 16 ° C. to recover the original pink color. It becomes a color state. This change could be made repeatedly by changing the temperature.

Example 2 Preparation of Resin Composition for Reversible Thermochromic Molding 30.0 parts by weight of microcapsule pigment containing reversible thermochromic composition 2, 5.0 parts by weight of fluorescent yellow pigment, ethylene-vinyl acetate Polymerized resin (melt flow rate: 1.
4) 1000.0 parts by weight, 10.0 parts by weight of an ultraviolet absorber, and 0.5 parts by weight of a metal soap lubricant are mixed and uniformly dispersed by a tumbler mixer, and then molded using an extruder, and then subjected to reversible thermal discoloration. An ethylene-vinyl acetate copolymer resin pellet was obtained.

A reversible thermochromic hollow molded article in the form of a doll was obtained using the reversible thermochromic molding resin composition. As shown in FIG. 2, when the molded body is immersed in warm water at 40 ° C. and taken out once, it is yellow in that state, but when the molded body is allowed to cool, a blue-green color gradually starts to develop from 36 ° C. (T
₁ ), showing a complete color density at 27 ° C. (T ₂ ), gradually cooling blue-green when gradually cooled, and completely returning to yellow at 20 ° C. (T ₄ ). This change could be made repeatedly by changing the temperature.

Example 3 Preparation of Resin Composition for Reversible Thermochromic Molding 40.0 parts by weight of microcapsule pigment containing reversible thermochromic composition 3, 3.0 parts by weight of fluorescent pink pigment, 1000.0 parts of polypropylene resin 10 parts by weight, ultraviolet absorber
After mixing 0 parts by weight and 0.5 parts by weight of a metal soap-based lubricant and uniformly dispersing them with a Hensyl mixer, using an extruder,
A reversible thermochromic polypropylene resin pellet was obtained.

The reversible thermochromic molding resin composition was melt-spun to obtain a reversible thermochromic filament as a molded product. Hair was implanted on the head and tail of a horse-shaped toy using the filament. When the filament is immersed in warm water at 40 ° C. and taken out once, as shown in FIG. 2, it exhibits a blue state in that state, but gradually cools from 33 ° C. to purple (T). ₁ ), 20 ℃
, A complete color density (T ₂ ), and when left to cool, the purple color gradually diminishes and returns to the original pink color at 14 ° C. (T ₄ ). This change can be made repeatedly by changing the temperature.

Example 4 Preparation of Resin Composition for Reversible Thermochromic Molding 50.0 parts by weight of microcapsule pigment containing reversible thermochromic composition 4, 0.1 part by weight of yellow processed pigment, 0.1 part of green processed pigment. 01 parts by weight, 0.04 parts by weight of red processed pigment, 1
2100 parts by weight of nylon resin (melting point: 178 ° C.)
After mixing 10.0 parts by weight of the ultraviolet absorber and uniformly dispersing it with a Hensyl mixer, a reversible thermochromic 12 nylon resin pellet was obtained using an extruder.

The reversible thermochromic molding resin composition was melt-spun to obtain a reversible thermochromic filament as a molded product. The filament obtained by planting hair on the head of the doll using the filament has a blond color under a room temperature environment as shown in FIG. 1, but develops an orange color when immersed in warm water at 45 ° C. 25 out
It becomes blonde when immersed in water at ℃. This change could be made repeatedly by changing the temperature.

Example 5 Preparation of resin composition for reversible thermochromic molding 30.0 parts by weight of microcapsule pigment containing reversible thermochromic composition 5, styrene-butadiene copolymer resin (melt flow rate 7.3) 1000.0 parts by weight, 10.0 parts by weight of an ultraviolet absorber, and 0.5 parts by weight of a metal soap lubricant were mixed, uniformly dispersed by a tumbler mixer, and then subjected to reversible thermochromic styrene-butadiene using an extruder. A copolymer resin pellet was obtained.

Using the above-mentioned resin composition for reversible thermochromic molding, a dolphin-shaped reversible thermochromic molded article was obtained by injection molding using a dolphin mold. As shown in FIG. 1, the molded body is colorless in a room temperature environment, but turns blue when placed in hot water at 45 ° C. Take out of warm water 2
When immersed again in water at 5 ° C., it becomes a colorless state. This change could be made repeatedly by changing the temperature.

Example 6 Preparation of resin composition for reversible thermochromic molding 30.0 parts by weight of microcapsule pigment containing reversible thermochromic composition 6, 1000.0 polyester elastomer resin (melt flow rate 20.0) Parts by weight, 10.0 parts by weight of an ultraviolet absorber, and 0.5 parts by weight of a metallic soap-based lubricant were mixed and uniformly dispersed by a tumbler mixer, and then a reversible thermochromic polyester elastomer resin pellet was obtained by using an extruder. Was.

A hot curler type reversible thermochromic molded article was obtained by injection molding using a hot curler type mold using the reversible thermochromic molding resin composition. The molded body is colorless under a room temperature environment as shown in FIG.
It becomes pink at 55 ° C. or higher, and becomes colorless again at 30 ° C. when left in a room temperature environment. This change could be made repeatedly by changing the temperature.

Example 7 Preparation of Resin Composition for Reversible Thermochromic Molding 30.0 parts by weight of microcapsule pigment containing reversible thermochromic composition 7, ethylene-ethyl acrylate copolymer resin (melt flow rate 5.0) ) 1000.0 parts by weight, 10.0 parts by weight of ultraviolet absorbent, metal soap lubricant
After 5 parts by weight were mixed and uniformly dispersed with a tumbler mixer, a reversible thermochromic ethylene-ethyl acrylate copolymer resin pellet was obtained using an extruder.

The resin composition for reversible thermochromic molding was subjected to inflation molding to obtain a reversible thermochromic ethylene-ethyl acrylate copolymer resin film sheet. The film sheet is in a colorless and translucent state under a room temperature environment as shown in FIG. 2, but after warming the film sheet by body temperature or breath, it is gradually cooled to blue from 30 ° C. when left to cool for a while. (T ₁ ), shows the maximum color density at 25 ° C. (T ₂ ), and when cooled further, it returns to the original colorless and translucent state at 20 ° C. (T ₄ ). This change could be made repeatedly by changing the temperature.

Example 8 Preparation of Resin Composition for Reversible Thermochromic Molding 20.0 parts by weight of microcapsule pigment containing reversible thermochromic composition 8, 2.0 parts by weight of fluorescent pink pigment, addition reaction type silicone rubber 1000.0 parts by weight were mixed and uniformly dispersed to obtain a reversible thermochromic curable silicone composition.

After adding 10.0 parts by weight of a curing agent to the resin composition for reversible thermochromic molding, dispersing and mixing, a depth of 5 m was obtained.
m, and the mixture was cured at 150 ° C. for 30 minutes and left at room temperature for 1 day to obtain a star-shaped reversible thermochromic silicone molded body. The molded body has a pink color at room temperature as shown in FIG. 1, but becomes purple when immersed in warm water of 45 ° C., and becomes original pink when taken out of warm water and immersed in 25 ° C. water. Color. This change could be made repeatedly by changing the temperature.

[0050]

The reversible thermochromic molding resin composition of the present invention exhibits a color-developed state when heated from a decolored state, and exhibits a reversible color-change behavior in which the resin composition returns to the decolored state when the temperature is lowered from the color-developed state. In the system, it shows the reverse discoloration behavior of the conventional heat discoloration type thermochromic material that discolors in the general-purpose living temperature range, and it can be applied to various fields as a new thermochromic material
Satisfies practicality. Also, the molded article to which the reversible thermochromic molding resin composition is applied has similar discoloration characteristics, and has a variety of properties, such as temperature indicating materials, temperature detecting materials, forgery prevention, training elements, toys, and decorative articles. Applies to the field. In addition, a system that exhibits a unique reversible thermochromic behavior, in which the temperature rise due to heating from the decolored state is used as a trigger to start color development in the course of temperature decrease after heating, exhibit a color development state of the maximum color density, and return to the decolored state Provides a color change characteristic not seen in the conventional thermochromic composition, is applied to various fields similar to the above, and satisfies the specificity. In particular, when applied to the toy field, the reversible color-decoloring effect of color development / decoloration can be easily achieved by means of living temperature such as hot water, cold water, body temperature, or a slightly higher temperature than the living temperature range. Because it can appear, it can satisfy the unexpectedness and the taste of change, and can contribute to enhancing the marketability.

[Brief description of the drawings]

FIG. 1 is a graph showing a temperature-color density curve of a reversible thermochromic composition exhibiting a colored state by heating from a decolored state of the present invention.

FIG. 2 is a graph showing a temperature-color density curve of a reversible thermochromic composition having a color-changing function of starting color development in a temperature-falling process after heating, triggered by heating from a decolored state according to the present invention. It is.

FIG. 3 is a graph showing 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 T ₅ complete melting temperature

Continuation of the front page F term (reference) 4F071 AA02 AA03 AE09 AE21 AH03 AH19 BB04 BB05 BB06 BB09 BC01 4J002 AA011 AE032 AE052 AF012 BB031 BB061 BB071 BB121 BC051 CF101 CF171 CL031 EA0028 EB018 EB0 EA028 EA0 EA028 EA0 EA028 EP017 EP018 EU027 EU047 EU057 EU137 EV048 FD097 FD202 FD206 FD208 GK01 4L033 AB01 AC15 BA00 BA99 CA00 CA10

Claims (4)

[Claims] (1) an electron-donating color-forming organic compound,
(B) at least one electron-accepting compound selected from the alkoxyphenol compounds represented by the following general formula (1): (c) a reaction medium that reversibly causes the electron transfer reaction according to (a) or (b) above. A reversible thermochromic resin composition comprising a microcapsule pigment containing a reversible thermochromic composition comprising a compound and a molding resin. Embedded image (R represents an alkyl group.) 2. The reversible thermochromic molding resin composition according to claim 1, wherein the molding resin is a thermoplastic resin. 3. A molded article molded from the reversible thermochromic molding resin composition according to claim 1. 4. The molded article according to claim 3, wherein said molded article is a filament or a film.