WO2022065230A1

WO2022065230A1 - Reversible thermochromic composition and reversible thermochromic microcapsule pigment encapsulating same

Info

Publication number: WO2022065230A1
Application number: PCT/JP2021/034303
Authority: WO
Inventors: 勝幸藤田; 寛梅本
Original assignee: パイロットインキ株式会社; 株式会社パイロットコーポレーション
Priority date: 2020-09-28
Filing date: 2021-09-17
Publication date: 2022-03-31
Also published as: JPWO2022065230A1; TW202231791A

Abstract

[Problem] To provide: a reversible thermochromic composition that has excellent contrast between a colored state and a colorless state and also has excellent lightfastness when in the colored state; and a reversible thermochromic microcapsule pigment that encapsulates the reversible thermochromic composition. [Solution] A reversible thermochromic composition that includes (a) an organic electron-donating coloring compound, (b) a combination of compounds that have a specific structure and serve as electron-accepting compounds, and (c) a reaction medium that reversibly causes an electron transfer reaction to occur between component (a) and component (b) in a specific temperature range; and a reversible thermochromic microcapsule pigment that encapsulates the reversible thermochromic composition.

Description

Reversible thermochromic composition and reversible thermochromic microcapsule pigments containing it

The present invention relates to a reversible thermochromic composition and a reversible thermochromic microcapsule pigment containing the same. More specifically, a reversible thermochromic composition that is decolorized in a temperature range above the high temperature side discoloration point and develops a color in a temperature range below the low temperature side discoloration point, and a reversible thermochromic micro that contains the composition. Regarding capsule pigments.

Conventionally, an essential component is a reaction medium that reversibly causes an electron transfer reaction between an electron-donating color-developing organic compound, an electron-accepting compound, and an electron-donating color-developing organic compound and an electron-accepting compound in a specific temperature range. Disclosed is a reversible thermochromic composition that changes color from a color-developing state to a decoloring state. For example, Patent Document 1 discloses the above-mentioned reversible thermochromic composition, and in particular, discloses that a developer, which is an electron-accepting compound, has a specific structure alone or in combination of two or more. There is.

The reversible thermochromic composition is required to have a high density in a color-developed state, a low density in a decolorized state, and excellent contrast. Further, it is required to have excellent light resistance at the time of color development, that is, even if it is exposed to light in the color development state, the decrease in color development density is suppressed with the passage of time.

Japanese Unexamined Patent Publication No. 2010-126549

The present invention has been made based on the above-mentioned background techniques, and is a reversible thermochromic composition having a high density in a color-developed state, a low density in a decolorized state, and excellent light resistance, and a reversible thermochromic composition thereof. It is an object of the present invention to provide a reversible thermochromic microcapsule pigment comprising the above.

The reversible thermochromic composition according to the present invention is
(A) Electron-donating color-developing organic compounds and
(B) A combination of a compound selected from the group consisting of a compound represented by the formula (I) as an electron-accepting compound and a compound represented by the formulas (IIa) to (IIc).
(C) Includes a reaction medium that reversibly causes an electron transfer reaction by the component (a) and the component (b) in a specific temperature range.

(During the ceremony,
R ¹¹ is a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aryl substituted alkyl having 7 to 11 carbon atoms. A group (where the methylene (-CH _2- ) group in the alkyl group may be replaced by an oxy (-O-) group).
R ¹² and R ¹³ each have a linear or branched alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, and an alkenyl group having 6 to 10 carbon atoms, which may be independently substituted with a fluorine atom. It is an aryl group, an aryl substituted alkyl group having 7 to 11 carbon atoms, or a halogen atom.
n11, n12 and n13 are 0 to 2 independently of each other)

(During the ceremony,
R ^a1 and R ^a2 are each independently a linear or branched alkyl group having 1 to 17 carbon atoms which may be substituted with a hydrogen atom or a fluorine atom (here, methylene (-in the above-mentioned alkyl group) in the alkyl group. The CH _2- ) group may be replaced by an oxy (-O-) group or a carbonyl (-CO-) group).
R ^a3 and R ^a4 are linear or branched alkyl groups having 1 to 4 carbon atoms, alkenyl groups having 2 to 4 carbon atoms, or halogen atoms, which may be independently substituted with fluorine atoms or hydroxy groups, respectively. And
na3 and na4 are 0 to 2 independently of each other)

(During the ceremony,
R ^b1 and R ^b2 are independently linear or branched with a hydroxy group, a linear or branched alkoxy group having 1 to 9 carbon atoms, and 1 to 10 carbon atoms which may be substituted with a fluorine atom. It is an alkyl group, an alkoxy group having 2 to 10 carbon atoms, or a halogen atom.
nb1 is 0 to 3,
nb2 is 0 to 2)

(During the ceremony,
R ^c1 is a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms.
L is a single bond, a linear or branched alkylene group having 1 to 3 carbon atoms, an aryl substituted alkylene group having 7 to 9 carbon atoms, or an arylene group having 6 to 10 carbon atoms.
R ^c2 , R ^c3 and R ^c4 are independent, linear or branched alkyl groups having 1 to 4 carbon atoms which may be substituted with fluorine atoms, cyclic alkyl groups having 3 to 7 carbon atoms, and carbons. A linear or branched alkoxy group having a number of 1 to 3, an alkenyl group having 2 to 4 carbon atoms, or a halogen atom.
nc2, nc3 and nc4 are 0 to 3 independently of each other)

The reversible thermochromic microcapsule pigment according to the present invention comprises the above-mentioned reversible thermochromic composition.
The reversible thermochromic liquid composition according to the present invention comprises the above-mentioned reversible thermochromic microcapsule pigment and a vehicle.
The solid cursive or solid cosmetic according to the present invention comprises the above-mentioned reversible thermochromic microcapsule pigment and an excipient.
The reversible thermochromic molding resin composition according to the present invention comprises the above-mentioned reversible thermochromic microcapsule pigment and a molding resin.
The reversible thermochromic laminate according to the present invention comprises a support and a reversible thermochromic layer containing the above-mentioned reversible thermochromic microcapsule pigment.
The writing tool according to the present invention contains a writing tool ink containing a reversible thermochromic microcapsule pigment and a vehicle.

INDUSTRIAL APPLICABILITY The present invention is a reversible thermochromic composition having a high density in a color-developed state, a low density in a decolorized state, excellent contrast between a color-developed state and a decolorized state, and further excellent light resistance in the color-developed state, and a reversible thermochromic composition thereof. It is possible to provide a reversible thermochromic microcapsule pigment containing the above.

It is a graph explaining the hysteresis characteristic in the color density-temperature curve of the heat decolorizing type reversible thermochromic composition. It is a graph explaining the hysteresis characteristic in the color density-temperature curve of the heat decolorization type reversible thermochromic composition having color memory. It is a graph explaining the hysteresis characteristic in the color density | temperature curve of the heat color development type reversible thermochromic composition.

The reversible thermochromic composition of the present invention includes (a) an electron-donating color-developing organic compound, (b) an electron-accepting compound, and (c) the occurrence of a color reaction of the components (a) and (b). Examples thereof include a heat-decoloring type (decoloring by heating and developing color by cooling) reversible thermochromic composition containing at least three essential components of a reaction medium that determines a temperature.
The above-mentioned reversible thermochromic composition is described in Japanese Patent Publication No. 51-44706, Japanese Patent Publication No. 51-44707, Japanese Patent Publication No. 1-229398, etc., with a predetermined temperature (discoloration point) as a boundary. It discolors before and after that, and exhibits a decolorized state in the temperature range above the high temperature side discoloration point and a color development state in the temperature range below the low temperature side discoloration point. The other state is maintained for as long as the heat or cold required for the state to develop is applied, but returns to the state exhibited at room temperature when the heat or cold is no longer applied, the hysteresis width (ΔH). ) Is relatively small (ΔH = 1 to 7 ° C.), and a heat-decoloring type (decolorizes by heating and develops color by cooling) reversible thermochromic composition can be used (see FIG. 1).

Further, the hysteresis width described in JP-A No. 4-17154, JP-A-7-179777, JP-A-7-33997, JP-A-8-39936, JP-A-2005-1369, etc. The shape of the curve, which shows a large characteristic (ΔH = 8 to 70 ° C.) and plots the change in color density due to temperature change, is higher than the discoloration temperature range, contrary to the case where the temperature is raised from the lower temperature side than the discoloration temperature range. The color changes by following a path that is significantly different from the case of descending from the side, and the color development state in the temperature range of the complete color development temperature t ₁ or less, or the decolorization state in the high temperature range of the complete decolorization temperature t ₄ or more, Heat decolorization type with color memory in a specific temperature range [temperature range between color development start temperature t ₂ and decolorization start temperature t ₃ (substantial two-phase holding temperature range)] (decolorization by heating and color development by cooling) It is also possible to use a reversible thermochromic composition (see FIG. 2).

The components (a), (b), and (c) will be specifically described below.

The component (a), that is, the electron-donating color-developing organic compound is a component that determines a color and is a compound that donates electrons to the component (b), which is a color developer, to develop a color.

Examples of the electron-donating color-developing organic compound include a phthalide compound, a fluorine compound, a stirinoquinoline compound, a diazarodamine lactone compound, a pyridine compound, a quinazoline compound, and a bisquinazoline compound.

Examples of the phthalide compound include diphenylmethanephthalide compound, phenylindrill phthalide compound, indrill phthalide compound, diphenylmethane azaphthalide compound, phenyl indolyl azaphthalide compound, and derivatives thereof. Of these, phenylindrill azaphthalide compounds and derivatives thereof are preferable.
In addition, examples of the fluorin compound include an aminofluorane compound, an alkoxyfluorane compound, and a derivative thereof.

The compounds that can be used for the component (a) are illustrated below.
3,3-Bis (4-dimethylaminophenyl) -6-dimethylaminophthalide,
3- (4-Diethylaminophenyl) -3- (1-ethyl-2-methylindole-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-diethylaminophenyl) -3- (1-ethyl-2-methylindole-3-yl) -4-azaphthalide,
3- (2-n-Hexyloxy-4-diethylaminophenyl) -3- (1-ethyl-2-methylindole-3-yl) -4-azaphthalide,
3- [2-ethoxy-4- (N-ethylanilino) phenyl] -3- (1-ethyl-2-methylindole-3-yl) -4-azaphthalide,
3- (2-Acetamide-4-diethylaminophenyl) -3- (1-propyl-2-methylindole-3-yl) -4-azaphthalide,
3,6-bis (diphenylamino) fluorane,
3,6-Bis (N-Phenyl-N-p-Trillamino) Fluoran,
3,6-dimethoxyfluorane,
3,6-di-n-butoxyfluolane,
2-Methyl-6- (N-ethyl-N-p-trillamino) fluorane,
3-Chloro-6-cyclohexylaminofluorane,
2-Methyl-6-cyclohexylaminofluorane,
2-Chloroamino-6-di-n-butylaminofluorane,
2- (2-Chloroanilino) -6-di-n-butylaminofluorane,
2- (3-Trifluoromethylanilino) -6-diethylaminofluorane,
2- (3-Trifluoromethylanilino) -6-di-n-pentylaminofluorane,
2-Dibenzylamino-6-diethylaminofluorane,
2-N-Methylanilino-6- (N-ethyl-Np-trillamino) fluorane,
1,3-dimethyl-6-diethylaminofluorane,
2-Chloro-3-methyl-6-diethylaminofluorane,
2-anilino-3-methyl-6-diethylaminofluorane,
2-anilino-3-methoxy-6-diethylaminofluorane,
2-anilino-3-methyl-6-di-n-butylaminofluorane,
2-anilino-3-methoxy-6-di-n-butylaminofluorane,
2-Xylidino-3-methyl-6-diethylaminofluorane,
2-Anilino-3-methyl-6- (N-ethyl-N-p-tolylamino) fluorane,
6-diethylamino-1,2-benzofluorane,
6- (N-ethyl-N-isobutylamino) -1,2-benzofluorine,
6- (N-Ethyl-N-Isopentylamino) -1,2-benzofluorine,
2- (3-Methoxy-4-dodecoxystylyl) quinoline,
2-diethylamino-8-diethylamino-4-methylspiro [5H- [1] benzopyrano [2,3-d] pyrimidine-5,1'(3'H) -isobenzofuran] -3'-on,
2-Di-n-butylamino-8-di-n-butylamino-4-methylspiro [5H- [1] benzopyrano [2,3-d] pyrimidine-5,1'(3'H) -isobenzofuran] -3'-On,
2-Di-n-butylamino-8-diethylamino-4-methylspiro [5H- [1] benzopyrano [2,3-d] pyrimidine-5,1'(3'H) -isobenzofuran] -3'-on ,
2-Di-n-butylamino-8- (N-ethyl-N-isoamylamino) -4-methylspiro [5H- [1] benzopyrano [2,3-d] pyrimidine-5,1'(3'H) -Isobenzofuran] -3'-on,
2-Di-n-butylamino-8-di-n-pentylamino-4-methylspiro [5H- [1] benzopyrano [2,3-d] pyrimidine-5,1'(3'H) -isobenzofuran] -3'-On,
4,5,6,7-Tetrachloro-3- (4-dimethylamino-2-methoxyphenyl) -3- (1-n-butyl-2-methyl-1H-indole-3-yl) -1 (3H) ) -Isobenzofuranone,
4,5,6,7-Tetrachloro-3- (4-diethylamino-2-ethoxyphenyl) -3- (1-ethyl-2-methyl-1H-indole-3-yl) -1 (3H) -iso Benzofuranone,
4,5,6,7-Tetrachloro-3- (4-diethylamino-2-ethoxyphenyl) -3- (1-n-pentyl-2-methyl-1H-indole-3-yl) -1 (3H) -Isobenzofuranone,
4,5,6,7-Tetrachloro-3- (4-diethylamino-2-methylphenyl) -3- (1-ethyl-2-methyl-1H-indole-3-yl) -1 (3H) -iso Benzofuranone,
3', 6'-bis [phenyl (2-methylphenyl) amino] spiro [isobenzofuran-1 (3H), 9'-[9H] xanthene] -3-one,
3', 6'-bis [phenyl (3-methylphenyl) amino] spiro [isobenzofuran-1 (3H), 9'-[9H] xanthene] -3-one,
3', 6'-bis [phenyl (3-ethylphenyl) amino] spiro [isobenzofuran-1 (3H), 9'-[9H] xanthene] -3-one,
2,6-bis (2'-ethyloxyphenyl) -4- (4'-dimethylaminophenyl) pyridine,
2,6-bis (2', 4'-diethyloxyphenyl) -4- (4'-dimethylaminophenyl) pyridine,
2,6-bis (2,4-diethyloxyphenyl) -4- [4-bis (4-methyloxyphenyl) aminophenyl] pyridine,
2- (4'-Dimethylaminophenyl) -4-methoxyquinazoline,
4,4'-Ethylenedioxy-bis [2- (4-diethylaminophenyl) quinazoline]

As the fluorans, in addition to the compound having a substituent on the phenyl group forming the xanthene ring, the phenyl group having the substituent on the phenyl group forming the xanthene ring and the phenyl group forming the lactone ring also has a substituent (for example,). It may be a compound exhibiting a blue color or a black color having an alkyl group such as a methyl group and a halogen atom such as a chlorine atom).

The component (b), that is, the electron-accepting compound is a compound that receives electrons from the component (a) and functions as a color developer of the component (a).
The component (b) is a combination of a compound selected from the group consisting of the compound represented by the formula (I) and the compounds represented by the formulas (IIa) to (IIc).

The compound represented by the formula (I) is as follows.

During the ceremony
R ¹¹ is a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aryl substituted alkyl having 7 to 11 carbon atoms. A group (where the methylene (-CH _2- ) group in the alkyl group may be replaced by an oxy (-O-) group) and
Preferably, it is a hydrogen atom, a linear or branched alkyl group having 1 to 3 carbon atoms, or an aryl substituted alkyl group having 7 or 8 carbon atoms.
More preferably, it is an isopropyl group or a benzyl group.
More preferably, it is an isopropyl group.
In the present invention, the aryl group also includes an alkyl-substituted aryl group (for example, a tolyl group). The same applies to the subsequent aryl groups.
R ¹² and R ¹³ each have a linear or branched alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, and an alkenyl group having 6 to 10 carbon atoms, which may be independently substituted with a fluorine atom. It is an aryl group, an aryl substituted alkyl group having 7 to 11 carbon atoms, or a halogen atom.
Preferably, a linear or branched alkyl group having 1 to 4 carbon atoms (more preferably a methyl group), an alkenyl group having 2 to 4 carbon atoms (more preferably a 2-propenyl group), and an aryl having 7 or 8 carbon atoms. It is a substituted alkyl group (more preferably a methylbenzyl group, a benzyl group, or a phenethyl group), or a halogen atom (more preferably a chlorine atom or a bromine atom).
n11, n12 and n13 are independently 0 to 2, n11 is preferably 1 and n12 and n13 are preferably 0 or 1, respectively. In a more preferred form, the hydroxy group is present at the 4-position (para-position) of at least one of the benzene rings.

Specific examples of (I) include the following.
Bis (4-hydroxyphenyl) sulfone,
4-Benzyloxy-4'-hydroxydiphenyl sulfone,
4- (4-Methylbenzyloxy) -4'-hydroxydiphenylsulfone,
4- (4-n-propylbenzyloxy) -4'-hydroxydiphenylsulfone,
4- (4-Isopropylbenzyloxy) -4'-hydroxydiphenylsulfone,
2,4'-Dihydroxydiphenyl sulfone,
4-Hydroxydiphenyl sulfone,
4-Methyl-4'-hydroxydiphenyl sulfone,
4-n-propyl-4'-hydroxydiphenyl sulfone,
4-Isopropyl-4'-hydroxydiphenyl sulfone,
4-Methoxy-4'-hydroxydiphenyl sulfone,
4-n-propoxy-4'-hydroxydiphenyl sulfone,
4-Isopropoxy-4'-hydroxydiphenyl sulfone,
4- (2-propenyloxy) -4'-hydroxydiphenyl sulfone,
4- (β-Phenoxyethoxy) -4'-hydroxydiphenyl sulfone,
Bis [4-hydroxy-3- (2-propenyl) phenyl] sulfone,
Bis (3,5-dibromo-4-hydroxyphenyl) sulfone,
Bis (4-hydroxy-3-n-propylphenyl) sulfone,
Bis (4-hydroxy-3-methylphenyl) sulfone,
3', 4'-dihydroxy-4-methyldiphenyl sulfone,
3,4,4'-trihydroxydiphenyl sulfone,
Bis (3,4-dihydroxyphenyl) sulfone,
2,3,4-trihydroxydiphenylsulfone,
3-Benzyl-4-benzyloxy-4'-hydroxydiphenyl sulfone,
3-Phenethyl-4-phenethyloxy-4'-hydroxydiphenyl sulfone,
3-Methylbenzyl-4-methylbenzyloxy-4'-hydroxydiphenylsulfone,
4-Benzyloxy-3'-benzyl-4'-hydroxydiphenylsulfone,
4-Phenethyloxy-3'-Phenethyl-4'-Hydroxydiphenylsulfone,
4-Methylbenzyloxy-3'-methylbenzyl-4'-hydroxydiphenylsulfone

The compound represented by the formula (IIa) is as follows.

During the ceremony
R ^a1 and R ^a2 are each independently a linear or branched alkyl group having 1 to 17 carbon atoms which may be substituted with a hydrogen atom or a fluorine atom (here, methylene (-CH) in the alkyl group. _2- ) Group may be replaced by an oxy (-O-) group or a carbonyl (-CO-) group).
Preferably, it is a linear or branched alkyl group having 1 to 11 carbon atoms, which may be independently substituted with a hydrogen atom or a fluorine atom.
More preferably, at least one of R ^a1 and R ^a2 is a linear or branched alkyl group having 5 to 9 carbon atoms.
More preferably, one of ^Ra1 and ^Ra2 is a branched alkyl group having 5 to 9 carbon atoms and the other is a hydrogen or methyl group, respectively.
R ^a3 and R ^a4 are linear or branched alkyl groups having 1 to 4 carbon atoms, alkenyl groups having 2 to 4 carbon atoms, or halogen atoms, which may be independently substituted with fluorine atoms or hydroxy groups, respectively. It is preferably a linear or branched alkyl group (more preferably a methyl group) or a halogen atom (more preferably a fluorine atom) having 1 to 4 carbon atoms.
na3 and na4 are independently 0 to 2, preferably 0 or 1, respectively, and more preferably 0, respectively. In a more preferred form, each hydroxy group is present at the 4-position (para-position) of the benzene ring.

Specific examples of (IIa) include the following.
1,1-bis (4-hydroxyphenyl) n-hexane,
1,1-bis (4-hydroxyphenyl) n-octane,
1,1-bis (4-hydroxyphenyl) n-decane,
1,1-bis (4-hydroxyphenyl) -2-methylpropane,
1,1-bis (4-hydroxyphenyl) -2-ethylbutane,
1,1-bis (4-hydroxyphenyl) -2-ethylhexane,
2,2-Bis (4-hydroxyphenyl) propane,
2,2-bis (4-hydroxyphenyl) n-heptane,
2,2-Bis (4-hydroxyphenyl) n-dodecane,
2,2-Bis (4-hydroxyphenyl) -4-methylhexane,
2,2-Bis (4-hydroxyphenyl) hexafluoropropane,
2,2-Bis (4-hydroxy-3-methylphenyl) butane,
2,2-Bis (4-hydroxy-3-isopropylphenyl) propane,
2,2-Bis (3-fluoro-4-hydroxyphenyl) propane

The compound represented by the formula (IIb) is as follows.

During the ceremony
R ^b1 and R ^b2 are independently linear or branched with a hydroxy group, a linear or branched alkoxy group having 1 to 9 carbon atoms, and a linear or branched group having 1 to 10 carbon atoms which may be substituted with a fluorine atom. It is an alkyl group, an alkoxy group having 2 to 10 carbon atoms, or a halogen atom.
It is preferably a hydroxy group, a linear or branched alkyl group having 1 to 8 carbon atoms, and the like.
More preferably, it is a hydroxy group, or a linear or branched alkyl group having 3 to 6 carbon atoms.
More preferably, it is a hydroxy group, an isobutyl group, a sec-butyl group, or a tert-butyl group.
nb1 is 0 to 3, preferably 1. nb2 is 0 to 2, preferably 1. In a more preferred form, the hydroxy group is present at the 2-position (ortho-position) and 4-position (para-position) of one of the benzene rings.

Specific examples of (IIb) include the following.
2,4-Dihydroxybenzophenone,
4,4'-Dihydroxybenzophenone,
2,4-Dihydroxy-4'-n-propylbenzophenone,
2,4-Dihydroxy-4'-n-butylbenzophenone,
2,4-Dihydroxy-4'-isobutylbenzophenone,
2,4-Dihydroxy-4'-sec-butylbenzophenone,
2,4-Dihydroxy-4'-tert-butylbenzophenone,
2,4-Dihydroxy-4'-n-hexylbenzophenone,
2,4-Dihydroxy-2', 4'-dimethylbenzophenone,
2,4-Dihydroxy-2', 4', 6'-trimethylbenzophenone,
2,4-Dihydroxy-2'-methoxybenzophenone,
2,4-Dihydroxy-4'-ethoxybenzophenone,
2,4-Dihydroxy-2', 4'-dimethoxybenzophenone,
2,4-Dihydroxy-3', 4'-diethoxybenzophenone

The compound represented by the formula (IIc) is as follows.

During the ceremony
R ^c1 is a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms, preferably a hydrogen atom or a methyl group.
L is a single bond, a linear or branched alkylene group having 1 to 3 carbon atoms, an aryl substituted alkylene group having 7 to 9 carbon atoms, or an arylene group having 6 to 10 carbon atoms.
It is preferably a single bond, an ethylene group, or a group represented by the formula (i).
More preferably, it is a single bond or a group represented by the formula (i).

(In the group represented by the formula (i), the benzene ring is bonded to the carbon atom specified in the formula (IIc)).
R ^c2 , R ^c3 and R ^c4 are each independently a linear or branched alkyl group having 1 to 4 carbon atoms which may be substituted with a fluorine atom, a cyclic alkyl group having 3 to 7 carbon atoms, and carbon. A linear or branched alkoxy group having a number of 1 to 3, an alkenyl group having 2 to 4 carbon atoms, or a halogen atom, preferably a linear or branched alkyl group having 1 to 4 carbon atoms (more preferably a methyl group). ), A linear or branched alkoxy group (more preferably a methoxy group or an ethoxy group), a cyclohexyl group, or a halogen atom (more preferably a fluorine atom) having 1 to 3 carbon atoms.
nc2, nc3 and nc4 are independently 0 to 3, preferably 0 or 1, respectively, and more preferably 0, respectively. In a more preferred form, the hydroxy group is present at the 4-position (para-position) of each benzene ring.

Specific examples of (IIc) include the following.
4,4', 4 "-Methyllysine Trisphenol,
4,4'-[(4-Hydroxyphenyl) methylene] bis (2-methylphenol),
4,4'-[(4-Hydroxyphenyl) methylene] bis (2-cyclohexyl-5-methylphenol),
4,4', 4 "-Etlysine Trisphenol,
4,4', 4 "-ethylidinetris (2-methylphenol),
4,4'-[1- {4- [1- (4-Hydroxyphenyl) -1-methylethyl] phenyl} etylidene] bisphenol,
4,4'-[1- {4- [1- (4-Hydroxy-3-methylphenyl) -1-methylethyl] phenyl} etylidene] bis (2-methylphenol),
4,4'-[(3-ethoxy-4-hydroxyphenyl) methylene] bisphenol,
4,4'-[3- (5-cyclohexyl-4-hydroxy-2-methylphenyl) -3-phenyl) propylidene] bis (2-cyclohexyl-5-methylphenol),
4,4'-[(4-Hydroxyphenyl) methylene] bis (2-isopropylphenol),
4,4'-[1- {4- [1- (3-Fluoro-4-hydroxyphenyl) -1-methylethyl] phenyl} etylidene] bisphenol,
4,4'-[3- (2,5-dimethyl-4-hydroxyphenyl) butylene] bis (2,5-dimethylphenol),
1,1,3-Tris (4-hydroxyphenyl) propane,
1,2,2-Tris (4-hydroxyphenyl) propane,
1,3,3-Tris (4-hydroxyphenyl) butane,
1,4,4-Tris (4-hydroxyphenyl) pentane,
2,2-Bis (3-methyl-4-hydroxyphenyl) -1- (4-hydroxyphenyl) propane,
1- (3-Methyl-4-hydroxyphenyl) -2,2-bis (4-hydroxyphenyl) propane,
1- (3-Methyl-4-hydroxyphenyl) -3,3-bis (4-hydroxyphenyl) butane,
3,3-Bis (3-methyl-4-hydroxyphenyl) -1- (4-hydroxyphenyl) butane,
1,1,3-Tris (3-methyl-4-hydroxyphenyl) propane,
1,3,3-Tris (3-methyl-4-hydroxyphenyl) butane,
4,4'-[4- (4-Hydroxyphenyl) -sec-butylidene] bis (2-methylphenol)

By combining the compound represented by the formula (I) and the compound selected from the group consisting of the compounds represented by the formulas (IIa) to (IIc) as the component (b), the characteristics of each compound can be utilized. It is possible to provide a reversible thermochromic composition having excellent light resistance in a color-developed state. Specifically, it is possible to suppress a decrease in density even after being exposed to light for a certain period of time in a colored state.

Among the compounds represented by the formula (I), n11 is preferably 1, n12 and n13 are 0 or 1, respectively, and n12 and n12 are preferable because the light resistance of the reversible thermochromic composition can be easily improved. When n13 is 0, R ¹¹ is a linear or branched alkyl group having 1 to 3 carbon atoms, or an aryl substituted alkyl group having 7 or 8 carbon atoms, and the hydroxy group is at the 4-position of the benzene ring ( It is a compound existing in the para position), and when n12 and ⁿ¹³ are ¹ respectively, R11 is a hydrogen atom, and ^R12 and R13 are alkenyl groups having 2 to 4 carbon atoms, and hydroxy. It is a compound in which each group is present at the 4-position (para-position) of the benzene ring. More preferably, ⁿ¹¹ is 1, n12 and n13 are 0, respectively, R11 is a linear or branched alkyl group having 1 to 3 carbon atoms, and the hydroxy group is the 4-position (para-position) of the benzene ring. ) Is a compound present in. More preferably, it is a compound in which ⁿ¹¹ is 1, n12 and n13 are 0, respectively, R11 is an isopropyl group, and a hydroxy group is present at the 4-position (para-position) of the benzene ring.

Further, by combining the compound represented by the formula (I) and the compound selected from the group consisting of the compounds represented by the formulas (IIa) to (IIc) as the component (b), the light resistance in the color-developed state is excellent. At the same time, it is also possible to provide a reversible thermochromic composition having excellent color development density. The

Among the compounds represented by the formulas (IIa) to (IIc), the compound represented by the formula (IIa) or (IIb) is preferable because it is easy to obtain a reversible thermochromic composition having better light resistance. Further, the compound represented by the formula (IIa) is more preferable from the viewpoint that the difference between the color development density and the decolorization density is large, that is, the contrast between the color development state and the decolorization state is excellent. That is, as the component (b), a combination of the compound represented by the formula (I) and the compound represented by the formula (IIa) is preferable from the viewpoint of light resistance and the contrast between the color-developed state and the decolorized state.
Since the decoloring concentration of the reversible thermochromic composition can be lowered as compared with the case where the compound represented by the formula (I) is used alone as the component (b), the compound represented by the formula (I) can be lowered. As a compound represented by the formula (IIa) to be combined with, at least one of Ra1 and Ra2 is a linear or branched alkyl group having 3 to 9 carbon atoms, and ^na3 and ^na4 are 0, respectively. It is a compound in which a hydroxy group is present at the 4-position (para-position) of the benzene ring. More preferably, independently, one of Ra1 and Ra2 is a branched alkyl group having 5 to 9 carbon atoms, the other is a hydrogen atom or a methyl group, and ^na3 and ^na4 are 0, respectively. , A compound in which a hydroxy group is present at the 4-position (para-position) of the benzene ring, respectively.
That is, as the compound represented by the formula (I), ⁿ¹¹ is 1, n12 and n13 are 0, respectively, R11 is an isopropyl group, and a hydroxy group is present at the 4-position (para position) of the benzene ring. One of ^Ra1 and ^Ra2 is a linear or branched alkyl group having 5 to 9 carbon atoms, and the other is a hydrogen atom or a methyl group. The combination with the compound in which n3 and n4 are 0 respectively and the hydroxy group is present at the 4-position (para-position) of the benzene ring is most preferably used.

In a preferred embodiment of the present invention, the component (b) is a combination consisting only of the compound represented by the formula (I) and the compound represented by the formula (IIa). In this case, the mass ratio of the compound represented by the formula (I) to the compound represented by the formula (IIa) is preferably in the range of 1: 0.5 to 1: 5, more preferably 1: 1 to 1: 3. Is.
When the mass ratio of the compound represented by the formula (I) and the compound represented by the formula (IIa) is within the above range, the difference between the color development density and the decolorization density is large, that is, the color development state and the decolorization state. It becomes easy to obtain a reversible thermochromic composition having excellent contrast.

In a more preferred embodiment of the present invention, the component (b) is a combination consisting only of the compound represented by the formula (I), the compound represented by the formula (IIa), and the compound represented by the formula (IIb). As a result, a higher effect can be exhibited in the light resistance and the contrast between the color-developed state and the decolorized state.
In this case, the content of the compound represented by the formula (IIb) is preferably 5 to 25% by mass, more preferably 10 to 20% by mass, based on the total mass of the component (b).
The compound represented by the formula (IIb), which is combined with the compound represented by the formula (I) and the compound represented by the formula (IIa), is preferably nb1 is 1, nb2 is 1, and R ^b1 and R ^b2 . Is a compound that is independently a hydroxy group, an isobutyl group, a sec-butyl group, or a tert-butyl group. More preferably, nb1 is 1 and nb2 is 1, R ^b1 is an isobutyl group, sec-butyl group, or tert-butyl group, R ^b2 is a hydroxy group, and the hydroxy group is a benzene ring. It is a compound present at the 2-position (ortho-position) and the 4-position (para-position).

In any case, the content of the compound represented by the formula (IIa) is preferably 30 to 90% by mass, more preferably 40 to 80% by mass, and further preferably 40 to 80% by mass, based on the total mass of the component (b). It is preferably 45 to 75% by mass. Within the above range, it becomes easy to obtain a reversible thermochromic composition having excellent contrast between the color-developed state and the decolorized state.

The component (c) of the reaction medium that reversibly causes the electron transfer reaction by the component (a) and the component (b) in a specific temperature range will be described.
Examples of the component (c) include alcohols, esters, ketones, ethers and acid amides.
When the reversible thermochromic composition of the present invention is applied to microencapsulation and secondary processing, low molecular weight compounds evaporate outside the capsule when subjected to high heat treatment, so that they can be stably retained in the capsule. A compound having 10 or more carbon atoms is preferably used.

As alcohols, aliphatic monohydric saturated alcohol having 10 or more carbon atoms is effective.

As the esters, esters having 10 or more carbon atoms are effective, and any combination of a monovalent carboxylic acid having an aliphatic and an alicyclic or aromatic ring and a monovalent alcohol having an aliphatic and an alicyclic or an aromatic ring is effective. Esters, Aliphatic and Alicyclic Esters obtained from any combination of a polyvalent carboxylic acid having an aliphatic and alicyclic or aromatic ring and a monovalent alcohol having an aliphatic and an alicyclic or aromatic ring. Alternatively, esters obtained from any combination of a monovalent carboxylic acid having an aromatic ring and an aliphatic and a polyhydric alcohol having an alicyclic or aromatic ring can be mentioned.

Esters of saturated fatty acids and branched fatty alcohols, esters of unsaturated fatty acids or saturated fatty acids having branches or substituents with fatty alcohols that are branched or have 16 or more carbon atoms, cetyl butyrate, Ester compounds selected from stearyl butyrate and behenyl butyrate are also effective.

Further, in order to change the color by showing a large hysteresis characteristic with respect to the color density-temperature curve and to give color memory depending on the temperature change, the temperature is 5 ° C or higher and lower than 50 ° C described in Japanese Patent Publication No. 4-17154. A carboxylic acid ester compound showing a ΔT value (melting point-cloud point) can be exemplified.

Further, an odd aliphatic monohydric alcohol having 9 or more carbon atoms, a fatty acid ester compound obtained from an aliphatic carboxylic acid having an even number of carbon atoms, n-pentyl alcohol or n-heptyl alcohol, and an even number of 10 to 16 carbon atoms. A fatty acid ester compound having a total carbon number of 17 to 23 obtained from an aliphatic carboxylic acid is also effective.

As the ketones, aliphatic ketones having a total carbon number of 10 or more are effective, and arylalkyl ketones having a total carbon number of 12 to 24 can be mentioned.

As ethers, aliphatic ethers having a total carbon number of 10 or more are effective.

As the above-mentioned alcohols, esters, ketones, ethers, and acid amides, for example, the compounds described in JP-A-2020-700110 can be exemplified.

Further, the component (c) may be a compound represented by the following formula (1).

[In the formula, R ₁ represents a hydrogen atom or a methyl group, m represents an integer of 0 to 2, and either X ₁ or X ₂ is-(CH ₂ ) _n OCOR ₂ or (CH ₂ ) _n COOR. ₂ , the other indicates a hydrogen atom, n indicates an integer of 0 to 2, R ₂ indicates an alkyl group or an alkenyl group having 4 or more carbon atoms, and Y ₁ and Y ₂ independently indicate a hydrogen atom and carbon. Indicates any of an alkyl group, a methoxy group, or a halogen atom of the number 1 to 4, and r and p independently indicate an integer of 1 to 3].
Among the compounds represented by the formula (1), when R ₁ is a hydrogen atom, it is preferable because a reversible thermochromic composition having a wider hysteresis width can be obtained, and further, R ₁ is a hydrogen atom and m is The case of 0 is more preferable.
Of the compounds represented by the formula (1), the compound represented by the following formula (2) is more preferable.

(In the formula, R represents an alkyl group or an alkenyl group having 8 or more carbon atoms, preferably an alkyl group having 10 to 24 carbon atoms, and more preferably an alkyl group having 12 to 22 carbon atoms).

Further, the component (c) may be a compound represented by the following formula (3).

(In the formula, R represents an alkyl group or an alkoxy group having 8 or more carbon atoms, m and n each independently represent an integer of 1 to 3, and X and Y each independently represent a hydrogen atom and the number of carbon atoms. Indicates an alkyl group of 1 to 4, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom)

Further, the component (c) may be a compound represented by the following formula (4).

(In the formula, X indicates a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a methoxy group, or a halogen atom, m indicates an integer of 1 to 3, and n indicates an integer of 1 to 20).

Further, the component (c) may be a compound represented by the following formula (5).

(In the formula, R represents an alkyl group or an alkenyl group having 1 to 21 carbon atoms, and n represents an integer of 1 to 3).

Further, the component (c) may be a compound represented by the following formula (6).

(In the formula, X represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom, m represents an integer of 1 to 3, and n represents 1 to 20. Indicates an integer of)

Further, the component (c) may be a compound represented by the following formula (7).

(In the formula, R indicates any of an alkyl group having 4 to 22 carbon atoms, a cycloalkylalkyl group, a cycloalkyl group, and an alkoxy group having 4 to 22 carbon atoms, and X is a hydrogen atom and an alkyl having 1 to 4 carbon atoms. Indicates a group, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom, and n indicates 0 or 1).

Further, the component (c) may be a compound represented by the following formula (8).

(In the formula, R represents an alkyl group having 3 to 18 carbon atoms or an aliphatic acyl group having 3 to 18 carbon atoms, and X is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, and an alkoxy group having 1 or 2 carbon atoms. , Y indicates a hydrogen atom or a methyl group, Z indicates a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 or 2 carbon atoms, or a halogen atom).

Further, the component (c) may be a compound represented by the following formula (9).

(In the formula, R indicates any of an alkyl group having 4 to 22 carbon atoms, an alkenyl group having 4 to 22 carbon atoms, a cycloalkylalkyl group, and a cycloalkyl group, and X is a hydrogen atom, an alkyl group, an alkoxy group, and a halogen. Any of the atoms, Y indicates any of hydrogen atom, alkyl group, alkoxy group, halogen atom, n indicates 0 or 1)

Further, the component (c) may be a compound represented by the following formula (10).

(In the formula, R indicates any of an alkyl group having 3 to 18 carbon atoms, a cycloalkylalkyl group having 6 to 11 carbon atoms, a cycloalkyl group having 5 to 7 carbon atoms, and an alkoxy group having 3 to 18 carbon atoms. X indicates any of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, and a halogen atom, and Y indicates a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a methoxy group, and an ethoxy group. , Indicates one of the halogen atoms)

Further, the component (c) may be a compound represented by the following formula (11).

(In the formula, R represents a cycloalkyl group having 3 to 8 carbon atoms or a cycloalkylalkyl group having 4 to 9 carbon atoms, and n represents an integer of 1 to 3).

Further, the component (c) may be a compound represented by the following formula (12).

(In the formula, R represents any of an alkyl group having 3 to 17 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, and a cycloalkylalkyl group having 5 to 8 carbon atoms, and X is a hydrogen atom and 1 to 1 carbon atoms. Indicates any of 5 alkyl group, methoxy group, ethoxy group, and halogen atom, and n indicates an integer of 1 to 3).

As the compounds represented by the formulas (2) to (12), for example, the compounds described in JP-A-2020-700110 can be exemplified.

In addition, a heat-coloring type (coloring by heating and decoloring by cooling) using a gallic acid ester (Japanese Patent Laid-Open No. 51-44706, JP-A-2003-253149) as an electron-accepting compound is used for reversible thermal discoloration. It is also possible to apply a sex composition and a reversible thermochromic microcapsule pigment comprising the same (see FIG. 3).

The reversible thermochromic composition according to the present invention is a companion containing the above components (a), (b), and (c) as essential components, and the ratio of each component is the concentration, discoloration temperature, and discoloration. Although it depends on the form and the type of each component, the component ratio at which the desired characteristics are generally obtained is (a) component 1, (b) component 0.1 to 100, preferably 0.1 to 1. It is in the range of 50, more preferably 0.5 to 20, (c) component 5 to 200, preferably 5 to 100, and more preferably 10 to 100 (all of the above ratios are parts by mass).

Further, various light stabilizers may be added to the reversible thermochromic composition, if necessary.
The light stabilizer is contained in order to prevent photodegradation of the reversible thermochromic composition composed of the component (a), the component (b), and the component (c), and is 0 with respect to 1 part by mass of the component (a). .3 to 24 parts by mass, preferably 0.3 to 16 parts by mass. Further, among the light stabilizers, the ultraviolet absorber effectively blocks the ultraviolet rays contained in sunlight and the like, and prevents photodegradation caused by the excited state due to the optical reaction of the component (a). Further, antioxidants, singlet oxygen quenchers, superoxide anion quenchers, ozone quenchers and the like suppress the oxidation reaction by light.
As the light stabilizer, one kind or a mixture of two or more kinds can be used as appropriate.

The reversible thermosetting composition of the present invention is effective even when applied as it is, but may be encapsulated in microcapsules and referred to as a reversible thermosetting microcapsule pigment (hereinafter, referred to as "microcapsule pigment" or "pigment"). ), Or dispersed in a thermoplastic resin or a thermosetting resin to form reversible thermochromic resin particles (hereinafter, may be referred to as “resin particles”).
The reversible thermochromic composition is preferably encapsulated in microcapsules to form a reversible thermochromic microcapsule pigment. By encapsulating it in microcapsules, it is possible to form chemically and physically stable pigments, and further, the reversible thermodynamic composition is kept in the same composition under various usage conditions and is the same. This is because it can exert an action effect.
The microencapsulation is a conventionally known isocyanate-based interfacial polymerization method, melamine-formalin-based in-Situ polymerization method, in-liquid curing coating method, phase separation method from aqueous solution, phase separation method from organic solvent, and melting. There are a dispersion cooling method, an aerial suspension coating method, a spray drying method, and the like, which are appropriately selected according to the intended use. Further, a secondary resin film may be further provided on the surface of the microcapsules depending on the purpose to impart durability, or the surface characteristics may be modified for practical use.
The reversible thermochromic microcapsule pigment preferably has a mass ratio of inclusions: wall film of 7: 1 to 1: 1, and the mass ratio of inclusions and wall film is within the above range to develop color. The decrease in color density and sharpness of time is prevented. More preferably, the mass ratio of inclusions: wall membrane is 6: 1 to 1: 1.

The average particle size of the reversible thermochromic microcapsule pigment or resin particles is preferably in the range of 0.01 to 50 μm, more preferably 0.1 to 30 μm, and even more preferably 0.5 to 20 μm. If the average particle size of the microcapsule pigment or the resin particles exceeds 50 μm, the dispersion stability and processing suitability are lacking when blending into an ink, a paint, or a resin. On the other hand, if the average particle size is less than 0.01 μm, it becomes difficult to exhibit high-concentration color development.
When the microcapsule pigment or resin particles are used for writing ink, the average particle size is preferably 0.01 to 5 μm, more preferably 0.05 to 4 μm, still more preferably 0.1 to 3 μm, and particularly preferably 0.1 to 3 μm. Is in the range of 0.5 to 3 μm. If the average particle size of the pigment or resin particles exceeds 5 μm, it becomes difficult to obtain good ink ejection properties when used in a writing instrument. On the other hand, if the average particle size is less than 0.01 μm, it becomes difficult to exhibit high-concentration color development.
For the measurement of the average particle size, the particle area is determined by the image analysis type particle size distribution measurement software [Manufactured by Mountech Co., Ltd., product name: MacView], and the projected area circle equivalent diameter is determined from the area of the particle area. It is a value measured as the average particle diameter of particles corresponding to equal volume spheres by calculating (Heywood diameter).
If the particle size of all or most of the particles exceeds 0.2 μm, a particle size distribution measuring device [manufactured by Beckman Coulter Co., Ltd., product name: Multisizer 4e] is used by the Coulter method. It is also possible to measure as the average particle size of a considerable number of particles.
Furthermore, a laser diffraction / scattering type particle size distribution measuring device calibrated based on the numerical values measured using the above software or a measuring device by the Coulter method [manufactured by HORIBA, Ltd., product name: LA- 300], the particle size based on the volume and the average particle size may be measured.

Reversible thermochromic colorants such as reversible thermochromic compositions, reversible thermochromic microcapsule pigments or resin particles are dispersed in a vehicle containing water and / or an organic solvent and optionally various additives to form an ink composition. (Hereinafter, it may be referred to as "ink").
Used for printing ink / brush coating, spray coating, electrostatic coating, electrodeposition coating, sink coating, roller coating, dip coating, etc. used for screen printing, offset printing, process printing, gravure printing, coater, tampo printing, etc. Paints / Ink for inkjet / UV curable ink / For marking pens, for ball pens, for perpetual brushes, for brush pens, etc. It can be used as a reversible thermochromic liquid composition.

Various additives can be added to the reversible thermochromic liquid composition.
Additives include resins, cross-linking agents, curing agents, desiccants, plasticizers, viscosity regulators, dispersants, UV absorbers, antioxidants, light stabilizers, antisettling agents, smoothing agents, gelling agents, erasing agents. Examples thereof include foaming agents, matting agents, penetrants, pH regulators, foaming agents, coupling agents, moisturizing agents, antifungal agents, preservatives, rust preventives and the like.

Examples of the stationery vehicle used for the stationery ink include an oil-based vehicle containing an organic solvent, or a water-based vehicle containing water and, if necessary, an organic solvent.
When the vehicle is a water-based vehicle, the ink for writing tools may contain a water-soluble organic solvent compatible with water. The water-soluble organic solvent suppresses the evaporation of water from the ink, prevents fluctuations in the specific gravity of the vehicle, maintains good dispersion stability of the reversible thermochromic microcapsule pigment, and is a polymer flocculant or polymer described later. The structure of the loose aggregate formed by the flocculant and the dispersant can be stabilized.
Examples of the organic solvent include ethanol, propanol, butanol, glycerin, sorbitol, triethanolamine, diethanolamine, monoethanolamine, ethylene glycol, diethylene glycol, thiodiethylene glycol, polyethylene glycol, propylene glycol, butylene glycol, ethylene glycol monomethyl ether, and ethylene. Examples thereof include glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, sulfolane, 2-pyrrolidone, N-methyl-2-pyrrolidone and the like. can.

When the ink for writing tools contains a water-soluble organic solvent, the water-soluble organic solvent is preferably 1 to 40% by mass, more preferably 5 to 30% by mass, still more preferably 10 to 25% by mass, based on the total amount of the ink. It is blended in a range. When the blending ratio of the water-soluble organic solvent exceeds 40% by mass, the ink viscosity tends to increase. On the other hand, if the blending ratio is less than 1% by mass, the effect of suppressing water evaporation becomes poor.

When the writing instrument ink contains a water-soluble organic solvent and the hysteresis width (ΔH) of the reversible thermochromic microcapsule pigment to be blended in the writing instrument ink is large, the specific gravity of the microcapsule pigment is larger than 1, and the specific gravity of the vehicle is adjusted. When a water-soluble organic solvent having a specific gravity higher than that of water is used, it is easy to adjust the specific gravity. Therefore, it is preferable to use glycerin or the like having a specific gravity of more than 1.1 as the water-soluble organic solvent.

An ink for writing tools can be blended with a shear thinning agent, and an ink containing a shear thinning agent (shear thinning ink) can suppress aggregation and sedimentation of microcapsule pigments and cause bleeding of brush marks. Since it can be suppressed, a good brush stroke can be formed.
Furthermore, when the shear-reducing viscosity ink is stored in a writing instrument in the form of a ballpoint pen, ink leakage from the gap between the ball and the tip is prevented when the writing instrument is not used, or the writing tip is left facing upward (upright). It is possible to prevent the backflow of the ink in the case.

Examples of the shear reducing viscosity imparting agent include xanthan gum, welan gum, succinoglycan (average molecular weight of about 1 to 8 million) in which the constituent monosaccharides are organic acid-modified heteropolysaccharides of glucose and galactose, alkagum, guar gum, and locust bean. Gum and its derivatives, hydroxyethyl cellulose, alginic acid alkyl esters, polymers with a molecular weight of 100,000 to 150,000 containing alkyl esters of methacrylic acid as the main components, gelling ability extracted from seaweeds such as glucomannan, agar and caragenin. Has thickening polysaccharides, benzylidene sorbitol and benziliden xylitol or derivatives thereof, crosslinkable acrylic acid polymers, inorganic fine particles, polyglycerin fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyethylene glycol fatty acid ester, polyoxyethylene castor oil, poly Nonionic surfactants with HLB values of 8 to 12, such as oxyethylene lanolin, lanonine alcohol, beeswax derivatives, polyoxyethylene alkyl ethers, polyoxypropylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, fatty acid amides, dialkyls or dialkyls. Examples thereof include salts of alkenylsulfosuccinic acid, a mixture of N-alkyl-2-pyrrolidone and an anionic surfactant, a mixture of polyvinyl alcohol and an acrylic resin, and the like.

In addition, a polymer flocculant can be added to the ink for writing tools, and in the ink containing the polymer flocculant (aggregating ink), the microcapsule pigment forms a loose aggregate via the polymer flocculant. However, since the microcapsule pigments are prevented from coming into contact with each other and agglomerating, the dispersibility of the microcapsule pigment can be improved.

Examples of the polymer flocculant include polyvinylpyrrolidone, polyethylene oxide, and water-soluble polysaccharides.
Examples of the water-soluble polysaccharide include tragant gum, guar gum, pullulan, cyclodextrin, and a water-soluble cellulose derivative.
Further, examples of the water-soluble cellulose derivative include methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose and the like.
Among the above-mentioned polymer flocculants, hydroxyethyl cellulose is preferable because it has excellent dispersibility.

The polymer flocculant is preferably blended in the range of 0.1 to 1% by mass, more preferably 0.3 to 0.5% by mass, based on the total amount of the ink. Within the above range, the microcapsule pigment forms loose aggregates, and the effect of improving the dispersibility of the pigment can be sufficiently exhibited.

Further, the dispersity of the microcapsule pigment can be enhanced by adding a dispersant to the ink for writing tools.
Further, a polymer flocculant and a dispersant can be used in combination, and when both are used in combination, the dispersibility of the microcapsule pigment can be improved and the microcapsule pigment formed via the polymer flocculant can be used. The dispersibility of loose aggregates can be further improved.

Examples of the dispersant include polyvinylpyrrolidone, polyvinylbutyral, polyvinyl ether, styrene-maleic acid copolymer, ketone resin, hydroxyethylcellulose and its derivatives, synthetic resins such as styrene-acrylic acid copolymer, and acrylic polymers. Examples thereof include PO / EO adducts and amine-based oligomers of polyester.
Among the above dispersants, an acrylic polymer dispersant is preferable, an acrylic polymer dispersant having a carboxy group is more preferable, and a comb-shaped structure having a carboxy group in the side chain is preferable because the microcapsule pigment is excellent in dispersibility. The acrylic polymer dispersant of the above is more preferable.
A particularly preferable dispersant is an acrylic polymer dispersant having a comb-shaped structure having a plurality of carboxy groups in the side chain, and specific examples thereof include Japan Lubrizol K.K., product name: Solsparse 43000.
The dispersant is preferably blended in the range of 0.01 to 2% by mass, more preferably 0.1 to 1.5% by mass, based on the total amount of the ink. When the compounding ratio of the dispersant exceeds 2% by mass, the microcapsule pigment tends to settle or float when vibration or the like is applied from the outside. On the other hand, if the blending ratio is less than 0.01% by mass, the effect of improving the dispersibility is difficult to be exhibited.

Further, by blending a water-soluble resin with the ink for writing tools, it is possible to impart the adhesiveness and viscosity of the handwriting to the paper surface.
Examples of the water-soluble resin include alkyd resin, acrylic resin, styrene-maleic acid copolymer, cellulose derivative, polyvinylpyrrolidone, polyvinyl alcohol, dextrin and the like.
Among the above water-soluble resins, polyvinyl alcohol is preferable because it is excellent in stability of the acrylic polymer dispersant, and further, since the ink is highly soluble even in an acidic region, it is partially saponified with a saponification degree of 70 to 89 mol%. Degree-type polyvinyl alcohol is more preferable.
The water-soluble resin is preferably blended in the range of 0.3 to 3.0% by mass, more preferably 0.5 to 1.5% by mass, based on the total amount of the ink.

Furthermore, when the viscosity of the vehicle used in the ink for writing tools is low, by adding a specific gravity adjusting agent, it is possible to prevent the microcapsule pigment from settling or floating and being localized in the ink. The dispersion stability of the capsule pigment can be improved.

The dispersion stability of the pigment is maximized when the difference in specific gravity between the vehicle and the pigment is extremely small, and the specific gravity adjusting agent brings the specific gravity of the vehicle closer to the specific gravity of the pigment. Since the specific gravity of the vehicle depends on the specific gravity of the water-soluble substance dissolved in the vehicle and the amount of the water-soluble substance added thereto, the specific gravity of the vehicle becomes higher when a larger amount of the specific gravity adjusting agent having a large specific gravity is added to the vehicle and dissolved. Can be made larger.

Examples of the specific gravity adjusting agent include oxygen acids of Group 6 elements contained in the atomic weight range of 90 to 185 and salts thereof.
Such a specific gravity adjusting agent can adjust the specific gravity of the vehicle so as to be close to the pigment having a large specific gravity, and even though the ink has a low viscosity, the pigment is generated by external stimuli such as vibration. It is possible to suppress subsidence or ascent and localization.

The oxygen acid and its salt are selected from the group consisting of the transition metal element oxygen acid and its salt, and the oxygen acid ion is a tetrahedron or eight in which oxygen atoms are usually coordinated to metal atoms or the like. It is said to form a facet.
The oxygen acid and its salt may be a polyacid or a polyate which is a salt thereof, and the polyacid may be an isopolyacid, a heteropolyacid or the like, and the polyate may be an isopolylate, a heteropolylate or the like. included.

Examples of the specific gravity adjusting agent include a single oxygen acid and a salt thereof, an isopolyacid and a salt thereof, a heteropolyacid and a salt thereof and the like.
Examples of the single oxygen acid include molybdenum acid and tungstate, and examples of the single oxygen acid salt include sodium molybdenate, potassium molybdenate, ammonium molybdenate, sodium tungstate, potassium tungstate, and tungsten. Examples thereof include ammonium acid, lithium tungstate, and magnesium tungstate.
Examples of the isopolyacid include metamolybdate, paramolybdate, metatungstate, paratungstate, and isotungstate, and examples of the isopolylate include sodium metamolybdate, potassium metamolybdate, and meta. Ammonium molybdate, sodium paramolybdate, potassium paramolybdate, ammonium paramolybdate, sodium metatungstate, potassium metatungstate, ammonium metatungstate, barium metatungstate, sodium paratungstate, sodium isotungstate, etc. It can be exemplified.
Examples of the heteropolyacid include molybdrine acid, molybdosilicic acid, tonguestophosphate, tonguestosilicic acid, and the like, and further, as the heteropolyacid, sodium molybdrine acid, sodium molybdosilicate, sodium tonguestrate, sodium tonguestosilicate, and the like can be used. It can be exemplified.
The above oxygen acid and its salt can be used alone or in admixture of two or more.

Among the above specific gravity adjusting agents, metatungstate, paratungstate, sodium metatungstate, potassium metatungstate, ammonium metatungstate, barium metatungstate, sodium paratungstate, sodium isotungstate, tangstric acid, Sodium tungstate, sodium tungstate, and sodium tungstate are preferred, and sodium isotungstate, sodium metatungstate, and sodium paratungstate are more preferred.
The above sodium isotungstate, sodium metatungstate, and sodium paratungstate are not only highly safe, but also have a high specific density by themselves, so it is easy to adjust the liquid with a high specific density according to the amount added. , Suitable for use.

The specific gravity adjusting agent is preferably blended in the range of 2 to 20% by mass, more preferably 5 to 15% by mass, based on the total amount of the ink. When the blending ratio of the specific gravity adjusting agent exceeds 20% by mass, the microcapsule pigment is likely to aggregate. On the other hand, if the blending ratio is less than 2% by mass, the effect of adjusting the specific gravity of the vehicle becomes poor.
The mass ratio of the microcapsule pigment: the specific gravity adjusting agent is preferably 1: 0.05 to 4.0, more preferably 1: 0.075 to 2.0, and further preferably 1: 0.1 to 1. It is 5.

Vehicles containing the above-mentioned specific gravity adjusting agent are particularly effective for microcapsule pigments having a large specific gravity, and even though the ink has a low viscosity, the pigment settles in the ink when an external stimulus such as vibration is applied. Can be suppressed and the dispersion stability of the microcapsule pigment can be improved.
The specific gravity of the microcapsule pigment depends on the particle size, the components contained in the microcapsules and their contents, the components and film thickness of the capsule wall film, the coloring state of the microcapsule pigment, and the temperature. When the microcapsule pigment is in a completely colored state and water is used as a reference at 20 ° C., it is preferably 1.05 to 1.20. Such a pigment exhibits a property of having a large hysteresis width (ΔH), and can be decolorized by heating to maintain a decolorized state in a specific temperature range, but a pigment having a large hysteresis width (ΔH). Since a compound having two or more aromatic rings in the molecule is often used as the component (c), the specific gravity tends to be large, and it tends to settle in the ink and be easily separated. When irritation is applied, the pigment tends to settle and easily separate. However, in the ink containing the above specific gravity adjusting agent, although the ink has a low viscosity, it is possible to suppress the precipitation and localization of the microcapsule pigment and improve the dispersion stability of the pigment. Therefore, it is preferably used.
Considering the dispersion stability of the pigment in the ink, the specific gravity of the microcapsule pigment is 1.10 to 1.20 when the microcapsule pigment is in a completely colored state and water is used as a reference at 20 ° C. It is preferably 1.12 to 1.15, and more preferably 1.12 to 1.15.
The specific gravity of the microcapsule pigment can be measured by the following method.

(Method for measuring the specific gravity of microcapsule pigments)
1. 1. 30 ml of an aqueous glycerin solution and 1 g of a microcapsule pigment in a completely colored state are put into a screw tube bottle and mixed to obtain a microcapsule pigment dispersion.
2. 2. The temperature of 30 ml of the microcapsule pigment dispersion is adjusted to 20 ° C., and the mixture is centrifuged at a rotation speed of 1000 rpm for 30 seconds. As the centrifuge, a cooling / desktop centrifuge [manufactured by Kokusan Co., Ltd., product name: H103N] can be used.
3. 3. Observe the microcapsule pigment dispersion.
When most of the microcapsule pigment is precipitated at the bottom of the beaker, the state of the dispersion liquid is observed by performing the operations 1 and 2 again using the aqueous solution having a glycerin concentration higher than that of the glycerin aqueous solution at this time.
When it is confirmed that most of the microcapsule pigments are suspended on the liquid surface, use an aqueous solution having a lower glycerin concentration than the glycerin aqueous solution at this time, and perform steps 1 and 2 again to observe the state of the dispersion. ..
In the above series of operations, most of the microcapsule pigments are not floating or precipitating on the liquid surface, but the liquid surface of the glycerin aqueous solution and the parts other than the vicinity of the bottom of the screw tube bottle are uniformly colored. Repeat until the condition is visually confirmed. The specific gravity of the glycerin aqueous solution when this state is observed is measured and used as the specific gravity of the microcapsule pigment. The specific gravity of the glycerin aqueous solution can be measured by the floating method described in JIS K0061 7.1 for the aqueous solution whose temperature is adjusted to 20 ° C.

Further, the vehicle containing the above specific gravity adjusting agent has a specific density in the range of 1.00 to 1.30 when water is used as a reference substance at 20 ° C., and further, the specific gravity is 1.05 to 1. It is preferably .20, more preferably 1.08 to 1.18.
Further, the specific gravity of the vehicle is preferably 0.90 to 1.20 times, more preferably 0.95 to 1.10 times, the specific gravity of the above pigment.
If the specific gravity of the vehicle is within the above range and the specific gravity of the vehicle with respect to the specific gravity of the pigment is within the above range, the ink has a low viscosity when an external stimulus such as vibration is applied to the ink. It is possible to further suppress the precipitation and localization of the pigment in the ink, and further improve the dispersion stability of the pigment.

When the vehicle for writing tools is an aqueous vehicle, the vehicle contains at least water, but the water is preferably blended in the range of 30 to 80% by mass, more preferably 40 to 70% by mass, based on the total amount of ink. Will be done.

When writing ink is used for ball pens, higher fatty acids such as oleic acid, nonionic surfactants having long-chain alkyl groups, polyether-modified silicone oils, and thio-phosphoric acid tri (alkoxycarbonylmethyl ester) are used in the inks. And thio-phosphoric acid triesters such as thio-phosphoric acid tri (alkoxycarbonylethyl ester), phosphoric acid monoesters of polyoxyethylene alkyl ethers or polyoxyethylene alkylaryl ethers, polyoxyethylene alkyl ethers or polyoxyethylene alkylaryl ethers. It is preferable to add a phosphoric acid diester or a lubricant such as a metal salt, an ammonium salt, an amine salt or an alkanol amine salt thereof to prevent wear of the ball receiving seat.

In addition, if necessary, additives such as wetting agents, resins, resin particles, pH regulators, rust preventives, surfactants, wetting agents, defoaming agents, viscosity regulators, preservatives, and fungicides are added. You can also do it.

The reversible thermochromic microcapsule pigment is blended in the above-mentioned ink for writing tools in the range of preferably 5 to 40% by mass, more preferably 10 to 40% by mass, and further preferably 10 to 30% by mass with respect to the total amount of the ink. Will be done. When the blending ratio of the microcapsule pigment is within the above range, a desired color development density can be obtained and deterioration of ink outflow can be prevented.

The ink composition according to the present invention can be produced by any conventionally known method. Specifically, each of the above-mentioned components can be blended in a required amount and mixed with various stirrers such as propeller stirring, homodisper, or homomixer, and various dispersers such as bead mills to produce the product.

When the ink for writing tools according to the present invention is used for a ballpoint pen, its viscosity is settled or aggregated in a microcapsule pigment when measured under the condition of a rotation speed of 1 rpm (shear rate 3.84 sec ^-1 ) in an environment of 20 ° C. It is preferably 1 to 2000 mPa · s, more preferably 3 to 1500 mPa · s, and even more preferably 500 to 1000 mPa · s, because it can suppress the above. Further, when measured under the condition of a rotation speed of 100 rpm (shear rate 384 sec ^-1 ) in an environment of 20 ° C., the ink ejection property from the pen tip of the ballpoint pen can be improved, so that the viscosity is 1 to 200 mPa. -S is preferable, 10 to 100 mPa · s is more preferable, and 20 to 50 mPa · s is even more preferable. When the viscosity is within the above range, the dispersion stability of the microcapsule pigment and the easy flowability of the ink in the mechanism of the ballpoint pen can be maintained at a high level.
For the viscosity, use a shear meter [manufactured by TA Instruments, product name: Discovery HR-2, cone plate (diameter 40 mm, angle 1 °)], place the ink in an environment of 20 ° C, and rotate at a rotation speed of 1 rpm. It is a value measured under the condition of (shear rate 3.84 sec ^-1 ) or rotation speed 100 rpm (shear rate 384 sec ^-1 ).

When the ink for writing tools according to the present invention is used for a ballpoint pen, its surface tension is preferably 20 to 50 mN / m, more preferably 25 to 45 mN / m in an environment of 20 ° C. When the surface tension is within the above range, it is easy to suppress bleeding of the writing line and strike-through to the paper surface, and it is possible to improve the wettability of the ink on the paper surface.
For surface tension, use a surface tension measuring instrument [Kyowa Interface Science Co., Ltd., product name: DY-300], place the ink in an environment of 20 ° C, and use a vertical flat plate method using a platinum plate. It is a measured value.

When the ink for writing tools according to the present invention is used for a ballpoint pen, its pH is preferably 3 to 10, and more preferably 4 to 9. When the pH is within the above range, aggregation or precipitation of the microcapsule pigment contained in the ink in a low temperature range can be suppressed.
The pH is a value measured by placing the ink in an environment of 20 ° C. using a pH meter [manufactured by DKK-TOA CORPORATION, product name: IM-40S].

When the ink for writing tools according to the present invention is used for a marking pen, its viscosity is preferably 1 to 20 mPa · s when measured under the condition of a rotation speed of 30 rpm in an environment of 20 ° C., preferably 1 to 10 mPa · s. It is more preferably s, and even more preferably 1 to 5 mPa · s. When the viscosity is within the above range, the fluidity of the ink and the dispersion stability of the microcapsule pigment can be improved.
The viscosity is a value measured by placing the ink in an environment of 20 ° C. using a BL type rotary viscometer [manufactured by Toki Sangyo Co., Ltd., product name: TVB-M type viscometer, L type rotor]. Is.

When the ink for writing tools according to the present invention is used for a marking pen, its surface tension is preferably 25 to 50 mN / m, more preferably 25 to 45 mN / m in an environment of 20 ° C.35. It is more preferably ~ 45 mN / m. When the surface tension is within the above range, it is easy to suppress bleeding of the writing line and strike-through to the paper surface, and it is possible to improve the wettability of the ink on the paper surface.
The surface tension is determined by using a surface tension measuring instrument [Kyowa Interface Science Co., Ltd., product name: DY-300], placing the ink in an environment of 20 ° C, and using a vertical flat plate method using a glass plate. It is a measured value.

When the ink for writing tools according to the present invention is used for a marking pen, its pH is preferably 3 to 8, more preferably 4 to 7, and even more preferably 5 to 6. When the pH is within the above range, aggregation or precipitation of the microcapsule pigment contained in the ink in a low temperature range can be suppressed.
The pH is a value measured by placing the ink in an environment of 20 ° C. using a pH meter [manufactured by DKK-TOA CORPORATION, product name: IM-40S].

The above-mentioned ink for writing tools is housed in a writing tool provided with a pen tip and an ink filling mechanism.
Examples of the writing tool include various writing tools such as a ballpoint pen, a marking pen, a fountain pen, a brush pen, and a calligraphy pen.

The pen tip of the writing instrument is not particularly limited, and a pen tip equipped with various chips is used.
Among various chips, the ball pen tip includes, for example, a tip formed by holding a ball in a ball holding portion obtained by pressing and deforming the vicinity of the tip of a metal pipe inward from the outer surface, and cutting a metal material with a drill or the like. A chip formed by holding a ball in a ball holding portion formed by processing, a chip provided with a resin ball receiving seat inside a metal or plastic chip, or a ball held in the above chip is forward by a spring body. It is possible to exemplify what was urged to.
The material of the ballpoint pen tip and the ball is not particularly limited, and examples thereof include cemented carbide (cemented carbide), stainless steel, ruby, ceramic, resin, and rubber.
The diameter of the ball is preferably 0.1 to 3.0 mm, more preferably 0.2 to 2.0 mm, and even more preferably 0.3 to 1.0 mm. Further, the ball may be subjected to surface treatment such as DLC coating.

As the marking pen tip, for example, a resin processed body of a fiber, a fused processed body of a heat-meltable fiber, a felt body, etc. An example is a member or an extruded synthetic resin body having a plurality of axially extending ink outlet holes, and one end is processed into a shape suitable for the purpose such as a bullet shape, a rectangular shape, a chisel shape, etc. for practical use. Will be done.

The fountain pen-shaped tip (pen body) includes, for example, a metal plate such as a stainless steel plate or a gold alloy plate cut into a tapered shape and bent or curved, or a pen tip shape resin-molded. It can be exemplified. The pen body may be provided with a slit at the center or a ball portion at the tip thereof.

As the ink filling mechanism, for example, an ink container or an ink occlusion body capable of directly filling ink for writing tools can be exemplified.
As the ink container, for example, a molded body made of a thermoplastic resin such as polyethylene, polypropylene, polyethylene terephthalate, or nylon, or a metal tubular body is used, and the above chips are directly connected or the ink container is connected via a connecting member. And the chip may be connected.
The ink occlusion body is a fiber focusing body in which crimped fibers are focused in the longitudinal direction, and is embedded in a covering body such as a plastic cylinder or a film to adjust the porosity to approximately 40 to 90%. It is composed.

When filling ink for writing tools into a ballpoint pen, the structure and shape of the ballpoint pen itself are not particularly limited. For example, an ink container filled with shear-reducing viscosity ink is provided in a barrel, and the ink container is An example is a ballpoint pen in which a ball is communicated with a ballpoint pen tip attached to a tip portion, and a liquid stopper for preventing backflow is in close contact with the end face of the ink.

The rear end of the ink filled in the ink container is filled with the ink backflow prevention body composition.
The ink backflow inhibitor composition comprises a non-volatile liquid and / or a refractory liquid, eg, vaseline, spindle oil, castor oil, olive oil, refined mineral oil, liquid paraffin, polybutene, α-olefin, α-olefin oligomer or Examples thereof include co-oligomers, dimethyl silicone oils, methylphenyl silicone oils, amino-modified silicone oils, polyether-modified silicone oils, fatty acid-modified silicone oils, and the like.
The ink backflow prevention body composition may be used alone or in admixture of two or more.

It is preferable to add a thickener to the ink backflow prevention body composition to increase the viscosity to a suitable viscosity.
Examples of the thickener include silica having a hydrophobic treatment on the surface, fine particle silica having a methylated surface, aluminum silicate, swelling mica, a clay-based thickener such as bentonite and montmorillonite having a hydrophobic treatment, and magnesium stearate. , Fatty acid metal soaps such as calcium stearate, aluminum stearate, and zinc stearate, trivendilidene sorbitol, fatty acid amide, amide-modified polyethylene wax, hydrogenated castor oil, dextrine-based compounds such as fatty acid dextrin, and cellulose-based compounds can be exemplified. ..
Further, the liquid ink backflow prevention body composition described above and the solid ink backflow prevention body composition can also be used in combination.

Further, the shaft cylinder itself can be used as an ink filling mechanism, and a ballpoint pen in which ink is directly filled in the shaft cylinder and a ballpoint pen tip is attached to the front end of the shaft cylinder can be exemplified.

A ballpoint pen provided with a ballpoint pen tip and an ink filling mechanism may further include an ink supply mechanism for supplying the ink to be filled in the ink filling mechanism to the pen tip.

The ink supply mechanism is not particularly limited, but for example, (1) a mechanism in which an ink guide core made of a fiber bundle or the like is provided as an ink flow rate adjusting body and ink is supplied to the pen tip, (2) a comb groove shape. Ink flow control body is provided, and a mechanism that supplies ink to the pen tip by interposing it. Ink is dispensed through a pen core provided with a shaped ink guide groove and a ventilation groove wider than the groove, and an ink guide core for guiding ink from the ink filling mechanism to the pen tip is arranged at the axis. A mechanism for supplying to the pen tip can be mentioned.

The material of the pen core is not particularly limited as long as it is a synthetic resin that can be injection-molded into a structure in which a large number of disks are formed into a comb groove shape. Examples of the synthetic resin include general-purpose polycarbonate, polypropylene, polyethylene, acrylonitrile-butadiene-styrene copolymer (ABS resin) and the like. In particular, an acrylonitrile-butadiene-styrene copolymer (ABS resin) is preferably used because it has high moldability and easy to obtain pen core performance.

When the ballpoint pen is provided with the above-mentioned ink supply mechanism, the above-mentioned ink storage body can be used as the ink filling mechanism in addition to the above-mentioned ink container and shaft tube.

Specifically, the structure of the ballpoint pen that houses the ink for writing tools is as follows: (1) The ballpoint pen tip is directly connected to the ink container or via a connecting member, and the ink for writing tools is filled, and the end face of the ink is filled with ink. A ballpoint pen in which a ballpoint pen refill formed by filling a backflow prevention body is housed in a shaft cylinder, (2) a writing instrument ink is directly filled in the shaft cylinder, and a comb groove-shaped ink flow control body, a fiber bundle, etc. A ballpoint pen equipped with a mechanism to supply ink to the pen tip by interposing an ink guide core made of A ballpoint pen equipped with a mechanism to supply the pen tip, (4) an ink storage body made of a fiber bundle impregnated with ink for writing tools is housed in a shaft cylinder, and an ink guide core made of a fiber bundle or the like is sent to the ink flow rate. An example is a ballpoint pen provided with a mechanism for supplying ink to the pen tip by interposing it as an adjusting body.

When the marking pen is filled with ink for writing tools, the structure and shape of the marking pen itself are not particularly limited. A marking pen that communicates with a marking pen tip can be exemplified.
In addition to directly connecting the above-mentioned chip to the ink storage body, the ink storage body and the chip may be connected via a connecting member.

The marking pen provided with the marking tip and the ink filling mechanism may further include an ink supply mechanism for supplying the ink filled in the ink filling mechanism to the pen tip.

The ink supply mechanism is not particularly limited, but for example, in addition to the ink supply mechanism provided in the ballpoint pen described above, (4) an ink flow rate adjusting body by a valve mechanism is provided, and ink is sent to the pen tip by opening the valve. A mechanism for supplying can be mentioned.
As the valve mechanism, a conventional general-purpose pumping type that opens by pressing the tip can be used, and a valve mechanism set to a spring pressure that can be pressed and released by writing pressure is preferable.

When the marking pen is equipped with an ink supply mechanism, as the ink filling mechanism, in addition to the above ink occlusion body, an ink container capable of directly filling ink for writing tools can also be used. Further, the ink for writing tools may be directly filled by using the shaft cylinder itself as an ink filling mechanism.

Specifically, as the configuration of the marking pen for accommodating the writing instrument ink, (1) an ink storage body made of a fiber bundle impregnated with the writing instrument ink was accommodated in the shaft cylinder, and a capillary gap was formed. A marking pen tip made of a fiber-processed body or a resin molded body is directly connected to the shaft cylinder so that the ink storage body and the chip are connected, or is connected to the shaft cylinder via a connecting member. (2) Writing tool directly in the shaft cylinder. A marking pen, (3) shaft, which is filled with ink and is provided with a mechanism for supplying ink to the pen tip by interposing an ink guide core composed of a comb groove-shaped ink flow rate adjusting body or a fiber bundle as an ink flow rate adjusting body. A marking pen provided with a mechanism in which writing ink is directly filled in the cylinder and the ink is supplied to the pen tip via the pen core described above. (4) The tip and ink via a valve mechanism that opens by pressing the tip. A marking pen provided with an accommodating body and directly filling the ink accommodating body with ink for writing tools, and (5) an ink storage body composed of a fiber bundle impregnated with ink for writing tools, in an ink container containing a capillary gap. A marking pen tip made of a fiber-processed body or a resin molded body formed of a pen accommodates a marking pen refill directly connected to the ink storage body so that the tip is connected, or via a connecting member. A marking pen or the like can be exemplified.

Further, the above-mentioned ballpoint pen or marking pen may be in the form of an ink cartridge as a detachable structure. In this case, after the ink contained in the ink cartridge of the writing instrument is used up, it can be used by replacing it with a new ink cartridge.
As the ink cartridge, one that also serves as a shaft cylinder that constitutes a writing tool by being connected to the writing tool main body, or one that covers and protects the shaft cylinder (rear shaft) after being connected to the writing tool main body is used. In the latter case, in addition to using the ink cartridge alone, the writing instrument before use may be used by connecting the writing instrument body and the ink cartridge, or by connecting the ink cartridge in the barrel when the user of the writing instrument uses it. It may be any of those housed in the barrel in a disconnected state so as to start.

When the ballpoint pen or marking pen is directly filled with ink for writing tools, the ink is agitated in the ink container or shaft cylinder filled with the ink in order to facilitate the redispersion of the microcapsule pigment. It is preferable to incorporate a stirring body such as a stirring ball. Examples of the shape of the agitating body include a spherical body and a rod-shaped body. The material of the agitator is not particularly limited, and examples thereof include metal, ceramic, resin, and glass.

Furthermore, writing instruments such as ballpoint pens and marking pens are provided with a cap that is attached so as to cover the writing tip (tip tip), and a haunting mechanism that allows the writing tip to appear and disappear from the writing instrument body (shaft cylinder). It is preferable to provide it, and it is possible to prevent the writing tip from becoming dry and unable to write, and to prevent the writing tip from being contaminated or damaged.
A writing instrument provided with a haunting mechanism is housed in a barrel with the tip of the writing exposed to the outside air, and any writing instrument having a structure in which the tip of the writing protrudes from the opening of the barrel due to the operation of the hoisting mechanism is used. For example, the above-mentioned ballpoint pen refill or marking pen refill can be produced, and the refill is housed in the barrel so that the writing tip protrudes from the opening of the barrel by the operation of the haunting mechanism. It is possible to manufacture a writing instrument (a haunting type writing instrument) provided with a mechanism.
In addition, when the writing tool is provided with a haunting mechanism, a plurality of ballpoint pen refills or marking pen refills are accommodated in the barrel, and the writing tip of any of the refills is haunted from the barrel opening by the operation of the hoisting mechanism. It can also be a type of haunting writing tool (a haunting ballpoint pen or a haunting marking pen).

As the haunting mechanism, for example, (1) an operating portion (clip) that can move in the front-rear direction from the rear side wall of the axle cylinder is projected outward in the radial direction, and the operating portion is slid forward to operate the front end of the axle cylinder. Side-slide type infestation mechanism that allows the writing tip to appear and disappear from the opening, (2) Rear end knock that allows the writing tip to appear and disappear from the front end opening of the barrel by pressing the operation unit provided at the rear end of the barrel forward. Type infestation mechanism, (3) Side knock type infestation mechanism in which the writing tip is infested from the front end opening of the shaft cylinder by pressing the operation part protruding from the outer surface of the side wall of the shaft cylinder inward in the radial direction, (4) shaft. An example is a rotary infestation mechanism in which the writing tip is infested from the opening at the front end of the shaft by rotating the operation portion at the rear of the cylinder.

Furthermore, the form of the ballpoint pen or marking pen is not limited to the above configuration, and a tip with a different form can be attached, a pen tip for drawing out ink with a different color tone can be attached, and a tip with a different form can be attached. In addition, it may be a compound writing tool (double-headed type, pen tip feeding type, etc.) in which the color tone of the ink derived from each chip is different.

The handwriting obtained by writing on the writing surface using the writing instrument containing the above-mentioned writing instrument ink can be rubbed with a finger or discolored by a heating tool or a cooling tool.
Examples of the heating tool include an energizing heating discoloring tool equipped with a resistance heating element such as a PTC element, a heating discoloring tool filled with a medium such as hot water, a heating discoloring tool using steam or laser light, and application of a hair dryer. However, since the color can be changed by a simple method, a friction member and a friction body are preferable.
Examples of the cooling tool include a current-carrying cold-heat discoloring tool using a Pertier element, a cold-heat discoloring tool filled with a refrigerant such as cold water or ice pieces, a heat-retaining agent, and application of a refrigerator or a freezer.

As the friction member and the friction body, elastic bodies such as elastomers and plastic foams, which are rich in elasticity and can generate appropriate friction at the time of rubbing to generate frictional heat, are preferable, but plastic molded bodies, stone materials, wood, etc. Metal, cloth and the like can also be used.
The handwriting may be scratched by using a general eraser used for erasing the handwriting with a pencil, but since the eraser is generated at the time of rubbing, the above-mentioned friction member and the above-mentioned friction member in which almost no eraser is generated are generated. A friction body is preferably used.
Examples of the material of the friction member and the friction body include silicone resin and SEBS resin (styrene-ethylene-butadiene-styrene block copolymer). The SEBS resin is more preferably used because the silicone resin tends to adhere to the portion erased by rubbing and the handwriting tends to be repelled when writing repeatedly.

The above-mentioned friction member or friction body may be a member having an arbitrary shape separate from the writing tool, but by providing it in the writing tool, it can be made excellent in portability. Further, a writing tool set can also be obtained by combining a writing tool and a friction member or a friction body having an arbitrary shape separate from the writing tool.

In the case of a writing tool provided with a cap, the place where the friction member or the friction body is provided is not particularly limited, and for example, the cap itself is formed of the friction member, the barrel itself is formed of the friction member, or a clip is provided. In some cases, the clip itself may be formed of a friction member, or a friction member or a friction body may be provided at the tip end portion (top) of the cap, the rear end portion of the barrel (the portion where the writing tip portion is not provided), or the like.
When the writing tool is a haunting type writing tool, the place where the friction member or the friction body is provided is not particularly limited. For example, when the barrel itself is formed of the friction member or when a clip is provided, the clip itself is rubbed. It may be formed of a member, or a friction member or a friction body may be provided near the opening of the cylinder, the rear end of the cylinder (the part where the writing tip is not provided), or the knock portion.

Further, the above ink can also be used as a stamping ink.
Water is used as the medium for the stamp ink, but a water-soluble organic solvent can also be used if necessary.
When a microcapsule pigment is used as the stamp ink, glycerin or propylene glycol is preferable among the water-soluble organic solvents.

The water-soluble organic solvent is preferably blended in the range of 30 to 60% by mass, more preferably 30 to 55% by mass, and further preferably 40 to 50% by mass with respect to the total amount of the ink. When the blending ratio of the water-soluble organic solvent is within the above range, the ink does not dry or absorb moisture, and a clear image can be easily obtained.
If the blending ratio of the water-soluble organic solvent exceeds 60% by mass, the hygroscopicity tends to be high, and the image is blurred or mottled, so that it is difficult to obtain a clear image. On the other hand, if the blending ratio is less than 30% by mass, the stamp surface becomes dry and the stamp image is blurred, making it difficult to obtain a clear stamp image.

Further, an organic solvent can also be used as the above-mentioned medium.
Examples of the organic solvent include castor oil fatty acid alkyl esters, cellosolve-based solvents, alkylene glycol-based solvents, ester-based solvents, hydrocarbon-based solvents, halogenated hydrocarbon-based solvents, alcohol-based solvents, ether-based solvents, and ketone-based solvents. , A propionic acid solvent, a highly polar solvent, a mixed solvent thereof and the like can be exemplified.

Further, a thickener may be added to the stamp ink.
Among the thickeners, an alkali-soluble acrylic emulsion is preferable.
When an alkali-soluble acrylic emulsion is used as the thickener, the pH of the ink is preferably 6 to 11, more preferably 7 to 11, and even more preferably 7 to 10.

Further, by adding a binder resin to the stamp ink, the stickiness of the stamp image can be improved and the viscosity of the ink can be adjusted.
Examples of the binder resin include resin emulsions, alkali-soluble resins, and water-soluble resins.

The reversible thermochromic microcapsule pigment is blended in the stamp ink in a range of preferably 10 to 40% by mass, more preferably 10 to 35% by mass, and further preferably 10 to 30% by mass with respect to the total amount of the ink. Ru. When the blending ratio of the microcapsule pigment exceeds 40% by mass, the dispersion stability of the microcapsule pigment in the ink tends to decrease. On the other hand, when the blending ratio is less than 10% by mass, the color development density tends to decrease.

The above-mentioned stamp ink can be used as a stamp pad ink and a stamp ink provided with a stamp material having continuous pores.
For example, it is possible to obtain a stamp pad in which the stamp pad is impregnated with ink to supply the ink to the stamp surface of the stamp to be contacted. Further, a stamp can be obtained by impregnating a stamp material having a stamp material having continuous pores with ink.

The above stamp can form an image on various imprinted surfaces. Further, the stamp image formed by the stamp ink can be discolored by rubbing with a finger or applying the above-mentioned heating tool or cooling tool. As the heating tool, the above-mentioned friction member and friction body are preferable because the color can be changed by a simple method.

The above-mentioned friction member or friction body may be a member having an arbitrary shape separate from the stamp, but by providing the stamp, it can be made excellent in portability. Further, the stamp set can be obtained by combining the stamp and a friction member or a friction body having an arbitrary shape separate from the stamp.

When applying or printing a reversible thermochromic liquid composition, the material of the support is not particularly limited and is all effective, for example, paper, synthetic paper, fiber, cloth, synthetic leather, leather, plastic, glass. , Ceramic material, metal, wood, stone material, etc. can be exemplified.
The shape of the support is not limited to a planar shape, but may be an uneven shape.
By providing a reversible heat-changing layer containing a reversible heat-changing colorant on the support, a reversible heat-changing laminate (reversible heat-changing printed matter) can be obtained.
In the case where a non-thermally discoloring colored layer (non-thermally discoloring image) is previously formed on the support, the colored layer or the image can be concealed by the reversible thermal discoloration layer by a temperature change, and the change can be achieved. The aspect of can be further diversified.

Further, a reversible thermochromic colorant is melt-blended with an excipient and molded to obtain a solid molded product for reversible thermochromic coating, which can be used as a solid cursive or a solid cosmetic.
Examples of the solid cursive include a crayon, a pencil lead, a mechanical pencil lead, a solid gel marker, and the like.
Examples of the solid cosmetics include foundations, eyeliners, eyebrows, eyeshadows, lipsticks and the like.

Excipients used for solid cursive include waxes, gelling agents, clay minerals and the like.
Among the excipients, it is preferable to contain at least one of a polyolefin wax, a sucrose fatty acid ester, or a dextrin fatty acid ester because it is easy to improve the handwriting concentration.

Since the solid cursive has excellent mechanical strength and thermal discoloration characteristics and is easy to handle at the time of manufacture, the excipient preferably has a mass average molecular weight (Mw) of 2,000 to 50,000. More preferably, it is between 000 and 30,000. Further, those having a number average molecular weight (Mn) of 1,000 to 10,000 are preferable.
The mass average molecular weight and the number average molecular weight are values measured by gel permeation chromatography (GPC) based on polystyrene.

The excipient is preferably blended in the range of 0.2 to 70% by mass, more preferably 0.5 to 40% by mass, based on the total amount of the solid cursive. When the blending ratio of the excipient is within the above range, the shape as a solid cursive is easily obtained, and the handwriting concentration of the solid cursive is likely to be high.
If the blending ratio of the excipient exceeds 70% by mass, it becomes difficult to obtain a sufficient writing concentration. On the other hand, if the blending ratio is less than 0.2% by mass, it becomes difficult to obtain a shape as a writable core material.

Further, by blending a filler in the solid cursive, the strength of the solid cursive can be improved and the writing taste can be adjusted.
Among the fillers, talc or calcium carbonate is preferable because it has excellent moldability and does not easily impair the thermal discoloration characteristics when a microcapsule pigment is used.

The filler is preferably blended in the range of 10 to 65% by mass with respect to the total amount of solid cursive. If the blending ratio of the filler exceeds 65% by mass, the color development property and the writing quality tend to deteriorate. On the other hand, if the blending ratio is less than 10% by mass, the strength of the solid cursive tends to decrease.

Further, the strength of the solid cursive can be improved by blending a binder resin in the solid cursive.
Among the binder resins, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, and polyvinyl alcohol are preferable, and the molding stability can be improved by using these resins in combination with the polyester polyol.
The binder resin is preferably blended in the range of 0.5 to 5% by mass with respect to the total amount of the solid cursive.

Further, by blending a hindered amine compound in the solid cursive, it is possible to make it difficult to visually recognize the afterimage of the part where the handwriting on the writing surface is erased. Therefore, the appearance of the written surface is not spoiled, the rewriting property can be satisfied, and the commercial value can be enhanced.

In addition, if necessary, additives such as viscosity modifiers, fungicides, preservatives, antibacterial agents, UV inhibitors, antioxidants, lubricants, and fragrances can be added.

The solid cursive may be used alone as a cursive, or may be used as an inner core and may have a core-sheath structure (double core) provided with an outer shell covering the outer peripheral surface thereof.

If necessary, additives such as non-heat-discoloring colorants, fungicides, preservatives, antibacterial agents, ultraviolet absorbers, antioxidants, lubricants, and fragrances can be added to the outer shell.

The above solid cursive can be written on various writing surfaces, and since a reversible thermochromic colorant is used, the handwriting obtained by writing on the writing surface is a finger. The color can be discolored by rubbing with the above-mentioned heating tool or the application of the above-mentioned heating tool or cooling tool. As the heating tool, the above-mentioned friction member and friction body are preferable because the color can be changed by a simple method.

The above-mentioned friction member or friction body may be a solid cursive or a member having an arbitrary shape different from the exterior of the solid writing instrument in which the solid cursive is housed in the exterior container, but is a solid cursive or a solid cursive. By providing the solid cursive on the exterior of the solid writing instrument housed in the exterior container, the portability can be improved. Specific examples thereof include a pencil whose exterior is made of wood or paper, a crayon or the like, and a friction member provided. Further, a solid cursive set can also be obtained by combining a solid cursive with a friction member or a friction body having an arbitrary shape different from the solid cursive.

Further, the reversible thermosetting colorant can be melt-blended into a thermoplastic resin, a thermosetting resin, waxes, etc. to form pellets, powders, or pastes, and can be used as a resin composition for reversible thermosetting molding.
By means of general-purpose injection molding, extrusion molding, blow molding, casting molding, etc., the above-mentioned resin composition for reversible thermochromic molding can be used as a three-dimensional molded product, film, sheet, plate, filament, rod-shaped product, etc. A molded body in the form of a pipe or the like can be obtained.
In addition, toner and powder paint can also be obtained by melt-blending with a thermoplastic resin.

In addition, by blending a non-thermochromic colorant such as a general dye and a pigment into the above-mentioned reversible thermochromic liquid composition, solid molded article for coating, and resin composition for molding, the color is changed from (1). It exhibits a discoloration behavior to colored (2).

A layer containing a light stabilizer and / or a transparent metallic luster pigment is laminated on the above-mentioned molded body or laminated body to improve light resistance, or a top coat layer is provided to improve durability. You can also let them do it.
Examples of the light stabilizer include an ultraviolet absorber, an antioxidant, a singlet oxygen quenching agent, a superoxide anion quenching agent, an ozone quenching agent and the like.
Examples of the transparent metallic luster pigment include natural mica, synthetic mica, glass pieces, alumina, and pigments in which the surface of a transparent film piece is coated with a metal oxide such as titanium oxide as a core material.

Specific examples of the product using the reversible thermochromic composition and the microcapsule pigment or resin particles containing the composition include the following.
(1) Toys Dolls and animal figurines Toys, hair for dolls and animal figurines, doll houses and furniture, clothing, hats, bags, shoes and other doll accessories, accessory toys, stuffed animals, drawing toys, picture books for toys , Jigsaw puzzles and other puzzle toys, stacking toys, block toys, clay toys, fluid toys, frames, kites, musical instrument toys, cooking toys, gun toys, capture toys, background toys, vehicles, animals, plants, buildings, food, etc. Imitation toys, etc.
(2) Clothing T-shirts, sweatshirts, blouses, dresses, swimwear, raincoats, skiwear and other clothing, shoes and shoe strings and other footwear, handkerchiefs, towels, bathrobes and other cloth personal belongings, gloves, ties, hats, scarves. , Muffler, etc.
(3) Interior decorations Curtains, curtain strings, table hangings, rugs, cushions, carpets, rugs, chair upholstery, sheets, mats, picture frames, artificial flowers, photo stands, etc.
(4) Furniture Bedding such as futons, pillows, mattresses, lighting equipment, air conditioning equipment, etc.
(5) Ornaments Rings, bangles, tiaras, earrings, hair clips, artificial nails, ribbons, scarves, watches, eyeglasses, etc.
(6) Stationery Writing tools, stamping tools, erasers, underlays, rulers, notebooks, adhesive tapes, etc.
(7) Daily necessities Lipstick, eye shadow, foundation, eyeliner, eyebrow, nail polish, hair dye, artificial nails, cosmetics such as artificial nail paints, toothbrushes, etc.
(8) Kitchen utensils Cups, plates, chopsticks, spoons, forks, pots, frying pans, etc.
(9) Others Calendars, labels, cards, recording materials, various printed materials to prevent counterfeiting, books such as picture books, bags, packaging containers, embroidery threads, exercise equipment, fishing gear, coasters, musical instruments, cairo, ice packs, wallets Bags, umbrellas, vehicles, buildings, temperature detection indicators, training tools, etc.

An example is shown below. Unless otherwise specified, "parts" and "%" in the examples indicate "parts by mass" and "% by mass", respectively.

<Example 101>
Preparation of reversible thermochromic composition (a) As a component, 2,6-bis (2', 4'-diethyloxyphenyl) -4- (4'-dimethylaminophenyl) pyridine (A-1) 2 parts , (B) 3 parts of 4-isopropoxy-4'-hydroxydiphenyl sulfone (I-1), 7 parts of 1,1-bis (4-hydroxyphenyl) -2-ethylhexane (IIa-1) , (C) A reversible thermochromic composition in which 25 parts of behenyl alcohol (C-1) and 25 parts of stearyl stearate (C-2) are mixed and dissolved by heating to reversibly change color. Got This reversible thermochromic composition is added to a mixed solution consisting of 35 parts of an aromatic isocyanate prepolymer and 40 parts of an auxiliary solvent as a wall film material, and then emulsified and dispersed in an 8% polyvinyl alcohol aqueous solution. After continuing stirring while warming, 2.5 parts of water-soluble aliphatic modified amine was added, and further stirring was continued to prepare a microcapsule dispersion. A microcapsule pigment having an average particle size of 2.0 μm was obtained from the above microcapsule dispersion by centrifugation.

<Examples 102 to 107 and Comparative Examples 101 to 107>
Microcapsule pigments were obtained in the same manner as in Example 101, except that the types and amounts of the components (a), (b) and (c) were changed to those shown in Table 1.
The color tone of the obtained microcapsule pigment in the color-developed state is as shown in Table 1, and the color tone changed from the color-developed state to the decolorized state.
The numerical values of the component (a), the component (b), and the component (c) in the table indicate "parts by mass", and the numerical value of the concentration retention rate indicates "%".

The component (a), the component (b), and the component (c) in the table are the compounds shown below.
A-1 2,6-bis (2', 4'-diethyloxyphenyl) -4- (4'-dimethylaminophenyl) pyridine A-2- (3-trifluoromethylanilino) -6-di- n-Pentylaminofluorane I-1 4-isopropoxy-4'-hydroxydiphenyl sulfone I-2 bis [4-hydroxy-3- (2-propenyl) phenyl] sulfone I-3 4-benzyloxy-4'- Hydroxydiphenyl sulfone I-4 4-n-propoxy-4'-hydroxydiphenyl sulfone IIa-1 1,1-bis (4-hydroxyphenyl) -2-ethylhexane IIc-1 4,4'-[1- {4 -[1- (4-Hydroxyphenyl) -1-methylethyl] phenyl} etylden] bisphenol C-1 behenyl alcohol C-2 stearyl stearate C-3 4-benzyloxyphenylethyl capricate C-4 4-biphenylacetic acid cyclohexyl Methyl

[Discoloration temperature measurement]
40 parts of each microcapsule pigment obtained in Examples 101 to 107 and Comparative Examples 101 to 107, 52 parts of an ethylene-vinyl acetate copolymer resin emulsion, 5 parts of a thickener, and 3 parts of a leveling agent were mixed. A reversible thermochromic ink was prepared. A solid pattern was screen-printed on high-quality paper using the above ink to obtain a sample for measuring the discoloration temperature. Each of the above samples for measuring the discoloration temperature is set in the measurement part of a color difference meter [manufactured by Tokyo Denshi Co., Ltd., product name: TC-3600], and the sample part is heated and lowered at a rate of 2 ° C./min. , The brightness value was measured as the color density at each temperature, and the color density-temperature curve was created. Color density-From the temperature curve, complete color development temperature t ₁ , color development start temperature t ₂ , decolorization start temperature t ₃ , complete decolorization temperature t ₄ , ΔH [hysteresis width: (temperature between t ₃ and t ₄ )-( The temperature between t ₁ and t ₂ )] was determined. The results obtained are shown in Table 2 below.
The numerical values in the table indicate "℃".

[Light resistance evaluation]
40 parts of each microcapsule pigment of Examples 101 to 107 and Comparative Examples 101 to 107, 52 parts of an ethylene-vinyl acetate copolymer resin emulsion, 5 parts of a thickener, and 3 parts of a leveling agent are mixed and reversible. A thermochromic ink was prepared. A solid pattern was screen-printed on high-quality paper using ink to obtain a sample for measurement.
After cooling each of the above measurement samples to t1 or _less to achieve complete color development, set them in the measurement part of a fluorescence spectrodensitometer [manufactured by Konica Minolta Co., Ltd., product name: FD-7 type] to achieve complete color development. The absolute concentration of the state (hereinafter referred to as "initial concentration") was measured.
Next, each measured sample whose concentration was measured was subjected to a irradiance of 170 w / ^{m 2} _with a xenon light resistance tester [manufactured by Suga Test Instruments Co., Ltd., product name: Table Sun XT75] in a temperature environment not exceeding t3. The light was continuously irradiated for 10 hours.
After taking out each measurement sample after light irradiation and cooling it to t1 or _less to make it a complete color development state, each measurement sample is set in the measurement part of the above fluorescence spectrophotometer, and the complete color development state after light irradiation. Absolute concentration (hereinafter referred to as "concentration after light irradiation") was measured.
From the initial concentration value and the concentration value after light irradiation, the concentration retention rate [(concentration value after light irradiation) / (initial concentration value) × 100] was obtained. As for the concentration retention rate, the larger the value, the better the light resistance. The results obtained are as shown in Table 1.

<Examples 201 to 205, 301, 302 and Comparative Example 201>
Microcapsule pigments were obtained in the same manner as in Example 101, except that the types and amounts of the components (a), (b) and (c) were changed to those shown in Table 3.
The color tone of the obtained composition or the microcapsule pigment in the color-developed state is as shown in Table 3, and the color tone changed from the color-developed state to the decolorized state.
The numerical values of the component (a), the component (b), and the component (c) in the table indicate "parts by mass", and the numerical value of the concentration retention rate indicates "%".

The component (a), the component (b), and the component (c) in the table are the compounds shown below.
A-1 2,6-bis (2', 4'-diethyloxyphenyl) -4- (4'-dimethylaminophenyl) pyridine A-2- (3-trifluoromethylanilino) -6-di- n-Pentylaminofluorane A-3 2-anilino-3-methyl-6- (N-ethyl-N-p-tolylamino) fluorine I-1 4-isopropoxy-4'-hydroxydiphenyl sulfone IIa-1 1, 1-Bis (4-hydroxyphenyl) -2-ethylhexane IIa-2 2,2-bis (4-hydroxyphenyl) propane IIa-3 1,1-bis (4-hydroxyphenyl) -2-methylpropane IIa- 4 2,2-bis (4-hydroxyphenyl) hexafluoropropane IIb-1 2,4-dihydroxy-4'-tert-butylbenzophenone IIc-1 4,4'-[1- {4- [1- (4) -Hydroxyphenyl) -1-methylethyl] phenyl} etylden] bisphenol C-1 behenyl alcohol C-2 stearyl stearate C-3 4-benzyloxyphenylethyl capricate C-4 4-biphenylachexylmethylmethyl

[Discoloration temperature measurement]
40 parts of each microcapsule pigment obtained in Examples 201 to 205, 301, 302 and Comparative Example 201, 52 parts of an ethylene-vinyl acetate copolymer resin emulsion, 5 parts of a thickener, and 3 parts of a leveling agent were added. The inks were mixed to prepare a reversible thermochromic ink. A solid pattern was screen-printed on high-quality paper using the above ink to obtain a sample for measuring the discoloration temperature.
For each color change temperature measurement sample, t ₁ , t ₂ , t ₃ , and t ₄ were measured by the same measurement method as described above, and ΔH was determined. The results obtained are shown in Table 4 below.
The numerical values in the table indicate "℃".

[Concentration measurement]
40 parts of each microcapsule pigment obtained in Examples 101, 102, 106, 201 to 205, 301, 302 and Comparative Examples 101, 102, 106, 201, and 52 parts of an ethylene-vinyl acetate copolymer resin emulsion. Five parts of the thickener and three parts of the leveling agent were mixed to prepare a reversible thermochromic ink. A solid pattern was screen-printed on high-quality paper using ink to obtain a sample for density measurement.
The samples for measuring the densities of Examples 101, 102, 106, 201 to 205, 301, 302 and Comparative Examples 101, 102, 106, 201, which were cooled to t1 or _less and brought into a completely colored state, were subjected to a fluorescence spectrophotometer [ It was set in the measurement part of Konica Minolta Co., Ltd., product name: FD-7 type], and the absolute density of the color-developed state (hereinafter referred to as "color-developing density") was measured.
Further, the concentration measurement samples of Examples 101, 102, 106, 201 to 205, 301, 302 and Comparative Examples 101, 102, 106, 201, which _were heated to t4 or higher to be completely decolorized, were used as described above. The absolute concentration in the decolorized state (hereinafter referred to as "decoloring density") was measured by setting it in the measuring part of the fluorescence spectrophotometer. The results obtained are as shown in Table 3.

[Light resistance evaluation]
40 parts of each of the microcapsule pigments of Examples 201 to 205, 301, 302 and Comparative Example 201, 52 parts of an ethylene-vinyl acetate copolymer resin emulsion, 5 parts of a thickener, and 3 parts of a leveling agent are mixed. A reversible thermochromic ink was prepared. A solid pattern was screen-printed on high-quality paper using ink to obtain a sample for measurement.
For each of the above measurement samples, the concentration retention rate was determined by the same measurement method as above. The results obtained are as shown in Table 3.

Application example 1
Preparation of Reversible Thermal Discoloration Writing Tool (Reversible Thermal Discoloration Marking Pen) 23 parts of the microcapsule pigment (previously cooled to -20 ° C or lower to develop a yellow color) of Example 102 was subjected to a polymer flocculant (hydroxyethyl cellulose). ) [Dow Chemical Japan Co., Ltd., product name: CELLOSIZE WP-09] 0.4 parts and acrylic polymer dispersant [Japan Lubrizol Co., Ltd., product name: Solsparse 43000] 0.4 parts , Preservative (2-pyridinethiol 1-sodium oxide) [manufactured by Ronza Japan Co., Ltd., product name: sodium omadin] 0.2 parts and preservative (3-iodo-2-propynyl N-butylcarbamate) [Ronza Made by Japan Co., Ltd., Product name: Glycacil 2000] 0.2 parts, 30 parts of glycerin, 0.01 part of antifoaming agent, 0.03 part of pH adjuster (10% diluted phosphoric acid solution), and water. It was mixed in an aqueous vehicle consisting of 45.76 parts to prepare a reversible thermochromic liquid composition which is an ink for writing tools.
The above ink for writing tools is impregnated in the ink storage body coated with a polyester sliver with a synthetic resin film, and the pen body (chisel type) made of polyester fiber is placed at the tip of the shaft cylinder. , Assembled in a connected state via a resin holder, attached a cap, and made a marking pen. SEBS resin is attached to the rear end of the barrel as a friction member.
When yellow letters (handwriting) were formed by writing on the paper using the above marking pen, the handwriting was yellow at room temperature (25 ° C), and when the letters were rubbed with a friction member, the letters became It was decolorized and became colorless, and this state could be maintained unless it was cooled to −20 ° C. or lower. When the paper surface was placed in a freezer and cooled to -20 ° C or lower, the characters turned yellow again, and this discoloration behavior could be reproduced repeatedly.

Application example 2
Preparation of Reversible Thermochromic Solid Writing Tool 40 parts of microcapsule pigment of Example 103, 35 parts of filler (talc), and excipient (side chain crystalline polyolefin) [manufactured by Toyokuni Oil Co., Ltd., product name: HS Crysta 4100] 10 parts, excipient (polyolefin wax) [manufactured by Sanyo Kasei Kogyo Co., Ltd., product name: Sunwax 131-P (softening point 110 ° C, needle insertion degree 3.5)] 10 parts, styrene- Two parts of the acrylic acid copolymer, two parts of polyvinyl alcohol, and one part of the hindered amine-based light stabilizer were kneaded with a kneader to prepare a kneaded product for an inner core. Next, 69 parts of the filler (talc), 10 parts of the sucrose fatty acid ester, 10 parts of the excipient (polyolefin wax), and 10 parts of the ethylene-vinyl acetate copolymer were kneaded with a kneader and used for the outer shell. A talc was prepared. The outer shell kneaded material is wound around the outer peripheral surface of the inner core kneaded material so as to be the inner core, and compression molding is performed by a press. The outer diameter is φ3 mm and the length is 60 mm (the inner core is φ2 mm. By molding the outer shell into a coating thickness of 0.5 mm), a solid cursive with a core-sheath structure was produced. The above dimensions are set values, and a solid cursive is manufactured by cooling to −20 ° C. after compression molding and returning to room temperature.
A pencil was obtained by storing and molding the above solid cursive in a round outer shaft (wooden shaft). Further, a columnar friction body made of SEBS resin was fixed to the rear end of the pencil via a metal connecting member to produce a solid writing tool with a friction body (pencil with a friction body). When yellow letters (handwriting) were formed by writing on paper using the above solid writing instrument, the handwriting was yellow at room temperature (25 ° C), and when the letters were rubbed with a rubbing member, the letters became It was decolorized and became colorless, and this state could be maintained unless it was cooled to −20 ° C. or lower. When the paper surface was placed in a freezer and cooled to -20 ° C or lower, the characters turned yellow again, and this discoloration behavior could be reproduced repeatedly.

Application example 3
Preparation of Reversible Thermal Discoloration Stamp 20 parts of the microcapsule pigment of Example 104 (previously cooled to -20 ° C or lower to develop a yellow color), 50 parts of glycerin, and an alkali-soluble acrylic emulsion [Rohm and Haas]. -Manufactured by Haas Japan Co., Ltd., product name: Primal DR73] 1.5 parts, triethanolamine 0.9 parts, polyvinylpyrrolidone 50% aqueous solution 10 parts, silicone-based defoaming agent 0.2 parts, 0.5 part of the permeation leveling agent, 0.2 part of the preservative, and 16.7 parts of water were mixed to prepare a reversible thermochromic liquid composition which is an ink for stamping.
The stamp ink described above was impregnated into a stamp material having continuous pores, fixed to the stamp base material so that the stamp surface of the stamp material was exposed, and a cap was fitted to prepare a stamp. SEBS resin is attached to the rear end of the stamp base material as a friction member.
When the stamp is repeatedly pressed against the stamped surface (paper surface) using the above stamp, the ink smoothly flows out from the stamped surface of the stamp material and moves to the stamped surface, and a clear stamp image is continuously formed without blurring the stamp image. We were able to. The image is yellow at room temperature (25 ° C), and when scraped with a friction member, the image fades and becomes colorless, and this state can be maintained unless cooled to -20 ° C or lower. rice field. When the paper surface was placed in a freezer and cooled to −20 ° C. or lower, the image turned yellow again, and this discoloration behavior could be reproduced repeatedly.

Application example 4
Preparation of Reversible Thermal Discoloration Printed Material (Reversible Thermal Discoloration T-shirt) 30 parts of the microcapsule pigment of Example 105 (previously cooled to -20 ° C or lower to develop a yellow color) is subjected to an acrylic emulsion (solid content 45). %) 60 parts, 0.2 parts of defoaming agent, 1 part of viscosity adjusting agent, and 8.8 parts of water are uniformly mixed in an aqueous vehicle to form a reversible thermochromic liquid composition which is a printing ink. The thing was prepared.
A large number of star patterns are printed on a white T-shirt (made of cotton) as a support using the above printing ink using a 100-mesh screen plate, dried and cured to provide a reversible thermal discoloration layer, and reversible. A thermochromic printed matter (reversible thermochromic T-shirt) was produced.
In T-shirts, many yellow star patterns are visible on the surface of the T-shirt at room temperature (25 ° C) and do not change depending on body temperature or environmental temperature, but when heated to 64 ° C or higher, the part where the star pattern is printed becomes colorless and yellow. The star pattern is no longer visible. Moreover, when cooled to -20 ° C or lower, a yellow star pattern was visually recognized again. This change could be repeated.
In addition, a part of the star pattern on the surface of the T-shirt was decolorized by heating with an iron or the like to form a pattern in which only an arbitrary star pattern was decolorized, and the pattern of the T-shirt could be changed arbitrarily. .. In addition, the discolored state can be maintained at room temperature (25 ° C), and the entire T-shirt is heated to 64 ° C or higher to completely decolorize the star pattern, and then cooled to -20 ° C or lower to cool the star pattern. Was able to develop color again.

Application example 5
Preparation of reversible thermochromic printed matter 30 parts of microcapsule pigment (previously cooled to -20 ° C or lower to develop black color), 5 parts of red dye, and 65 parts of flax oil-based offset ink vehicle. Was mixed to prepare a reversible thermochromic liquid composition which is an ink for offset printing.
Offset printing was performed on both the front and back surfaces of high-quality paper as a printing medium using the above offset printing ink, and the paper was dried and cured to form a date (thermal discoloration image). The thermal discoloration images on the front surface and the back surface are formed so as not to overlap each other. Next, offset printing was performed using a non-color-changing black offset printing ink, and the printed matter was dried and cured to form a border (non-color-changing image) to produce a reversible heat-color-changing printed matter.
The above-mentioned reversible thermochromic printed matter is a notebook-shaped printed matter in which a black date is initially formed, but due to frictional heat generated by rubbing a thermal discoloration image at an arbitrary part on the surface using a friction member. Since it can be discolored to red and the discolored state can be maintained at room temperature (25 ° C.), it was useful for managing the schedule of holidays. In addition, on the dates provided on the back surface of the discolored portion, heat is not transferred when the thermal discoloration image on the front surface is discolored, and the discoloration does not occur, so that accurate schedule management can be performed.

Application example 6
Preparation of Reversible Thermal Discoloration Recording Material (Card for Information Display) Leveling 40 parts of the microcapsule pigment of Example 107 (previously cooled to -20 ° C or lower to develop a black color) with 50 parts of a urethane resin emulsion. A reversible thermochromic liquid composition, which is a printing ink, was prepared by uniformly mixing in an aqueous vehicle consisting of 3 parts of an agent and 1 part of a thickener.
A transparent anchor coat layer made of a urethane resin and an isocyanate-based curing agent is provided on the surface of a transparent polyester film (thickness 25 μm) having an adhesive layer on the back surface as a support, and the above printing ink is applied to the upper layer of the screen. Solid printing was performed using a plate, dried and cured to provide a reversible thermal discoloration layer. Further, a transparent protective layer containing an epoxy acrylate oligomer, a polyester acrylate oligomer, and an acrylate monomer was provided on the upper layer, and the material was irradiated with ultraviolet rays and polymerized to prepare a reversible thermochromic recording material. Next, the above recording material was attached to a white polyester film (thickness 188 μm) as a base material, and used as an information display card for practical use.
The reversible thermal discoloration recording material was once cooled to −20 ° C. or lower to completely develop a black color in the reversible thermal discoloration layer, and then character information was printed by a thermal printer equipped with a thermal head.
In the above recording material, white character information (excluded characters) is clearly displayed on a black background, and white character information is visually recognized as long as it is maintained in a temperature range above -20 ° C and below 60 ° C. rice field. Further, when the above-mentioned recording material was cooled to −20 ° C. or lower to completely develop the color of the reversible thermal discoloration layer in black, the white characters were not visible. From this state, it was possible to form white blank characters on the reversible thermal discoloration layer again using a thermal printer, and the above recording material could be used over and over again.

Application example 7
Fabrication of a doll toy with hair using a reversible heat-discoloring composite fiber 5 parts of microcapsule pigment of Example 201, 1 part of dispersant, nylon 12 (94 parts) having a melting point of 180 ° C., and a general blue pigment. 0.1 part was melt-mixed with an extruder at 200 ° C. to prepare a resin composition for reversible thermochromic molding in pellet form for the core part.
The above pellets are supplied to the core forming extruder, and nylon 12 natural pellets are supplied to the sheath forming extrusion machine. Using a composite fiber spinning device, the core: sheath volume ratio is 6: 4. A reversible thermochromic composite fiber composed of 18 single yarns having an outer diameter of 90 μm was prepared by spinning at 200 ° C. from an 18-hole discharge hole.
Once the reversible thermochromic composite fiber is cooled to -20 ° C or lower to completely develop the color of the microcapsule pigment, the reversible thermochromic composite fiber is a mixture of yellow due to the microcapsule pigment and blue due to the general pigment. It showed a green color. The reversible thermochromic composite fiber was transplanted to the head of the doll by a conventional method, and a doll toy having hair using the reversible thermochromic composite fiber was produced.
The hair of the above-mentioned doll toy did not change depending on the body temperature or the environmental temperature, but changed from green to blue when heated to 62 ° C or higher. Moreover, when it was cooled to -20 ° C or lower, it turned green again. This change could be repeated.
In addition, a part of the hair was decolorized by heating with a dryer or the like to form a pattern in which only an arbitrary part was decolorized, and the color of the hair could be arbitrarily changed. In addition, the discolored state can be maintained at room temperature (25 ° C), and the entire hair can be heated to 62 ° C or higher to decolorize it, and then cooled to -20 ° C or lower to develop a green color again. rice field.

Application example 8
Preparation of Reversible Thermal Discoloration Writing Tool (Reversible Thermal Discoloration Ball Pen) 25 parts of the microcapsule pigment of Example 202 (previously cooled to -20 ° C or lower to develop a yellow color) and a shear defoaming agent (xanthan gum). 0.3 parts, 10 parts of urea, 10 parts of glycerin, 0.5 parts of nonionic permeability-imparting agent [manufactured by San Nopco Ltd., product name: Nopco SW-WET-366], and modified silicone-based defoaming agent. Agent [manufactured by San Nopco Ltd., product name: Nopco 8034] 0.1 part, phosphate ester-based surfactant [manufactured by Daiichi Kogyo Seiyaku Co., Ltd., product name: Plysurf AL] 0.5 parts, Mix 0.5 parts of a pH adjuster (triethanolamine), 0.2 parts of a fungicide [manufactured by Ronza Japan Co., Ltd., product name: Proxel XL-2], and 52.9 parts of water. A reversible thermochromic liquid composition, which is an ink for writing tools, was prepared.
After the above ink for writing tools was suction-filled in an ink storage tube made of a polypropylene pipe, a cemented carbide ball having a diameter of 0.5 mm was connected to a ballpoint pen tip held at the tip via a resin holder. Next, a ballpoint pen refill was prepared by filling the rear end of the ink storage tube with an ink backflow preventive body (liquid plug) having viscoelasticity containing polybutene as a main component. The above refill was incorporated into a barrel to obtain a ballpoint pen (a haunting type ballpoint pen).
The above ballpoint pen is housed in the barrel with the tip provided in the ballpoint pen refill exposed to the outside air, and is operated by a clip-shaped retracting mechanism (slide mechanism) provided on the rear side wall of the barrel. The structure is such that the tip protrudes from the opening at the front end of the barrel. SEBS resin is attached to the rear end of the barrel as a friction member.
When yellow characters (handwriting) were formed by writing on the paper using the above ballpoint pen, the handwriting was yellow at room temperature (25 ° C), and when the characters were rubbed with a friction member, the characters disappeared. It became colorless in color, and this state could be maintained unless it was cooled to −20 ° C. or lower. When the paper surface was placed in a freezer and cooled to -20 ° C or lower, the characters turned yellow again, and this discoloration behavior could be reproduced repeatedly.

Application example 9
Preparation of Reversible Thermal Discoloration Plug 2.5 parts of microcapsule pigment of Example 203 (previously cooled to -20 ° C or lower to develop yellow color) and 1.5 parts of blue general pigment are vinyl acetate. -A paint used for spray painting by stirring and mixing in an oil-based vehicle consisting of 12.5 parts of vinyl acetate copolymer resin, 38.3 parts of xylene, 45 parts of butyl acetate, and 0.2 parts of viscosity modifier. A reversible thermochromic liquid composition was prepared.
As a support, the plug portion (white) of a household electric cord was spray-painted with the above paint and dried to provide a reversible heat-discoloring layer, thereby producing a reversible heat-discoloring plug.
The reversible thermochromic plug is green at room temperature (25 ° C), and when it turns blue at a temperature of 59 ° C or higher, it can maintain the blue discoloration state unless it is cooled to -20 ° C or lower. It was possible to visually confirm the temperature history when the temperature reached a high temperature range of 61 ° C. or higher due to overheating.

Application example 10
Preparation of Reversible Thermal Discoloration Writing Tool (Reversible Thermal Discoloration Ball Pen) 25 parts of the microcapsule pigment (previously cooled to -20 ° C or lower to develop a yellow color) of Example 204, and a shear defoaming agent (xanthan gum). 0.3 parts, 10 parts of urea, 10 parts of glycerin, 0.5 parts of nonionic permeability-imparting agent [manufactured by San Nopco Ltd., product name: Nopco SW-WET-366], and modified silicone-based defoaming agent. Agent [manufactured by San Nopco Ltd., product name: Nopco 8034] 0.1 part, phosphate ester-based surfactant [manufactured by Daiichi Kogyo Seiyaku Co., Ltd., product name: Plysurf AL] 0.5 parts, Mix 0.5 parts of a pH adjuster (triethanolamine), 0.2 parts of a fungicide [manufactured by Ronza Japan Co., Ltd., product name: Proxel XL-2], and 52.9 parts of water. A reversible thermochromic liquid composition, which is an ink for writing tools, was prepared.
After the above ink for writing tools was suction-filled in an ink storage tube made of a polypropylene pipe, a stainless steel ball having a diameter of 0.5 mm was connected to a ballpoint pen tip held at the tip via a resin holder. Next, from the rear end of the ink storage tube, an ink backflow preventive body (liquid plug) having viscoelasticity containing polybutene as a main component is filled, and the tail plug is fitted to the rear part of the pipe to form a front shaft cylinder and a rear shaft. After assembling the cylinder and fitting the cap, deaeration treatment was performed by centrifugation to prepare a ballpoint pen. SEBS resin is attached to the rear end of the rear axle cylinder as a friction member.
When yellow characters (handwriting) were formed by writing on the paper using the above ballpoint pen, the handwriting was yellow at room temperature (25 ° C), and when the characters were rubbed with a friction member, the characters disappeared. It became colorless in color, and this state could be maintained unless it was cooled to −20 ° C. or lower. When the paper surface was placed in a freezer and cooled to -20 ° C or lower, the characters turned yellow again, and this discoloration behavior could be reproduced repeatedly.

Application example 11
Preparation of Reversible Thermal Discoloration Writing Tool (Reversible Thermal Discoloration Marking Pen) 20 parts of the microcapsule pigment (previously cooled to -20 ° C or lower to develop a black color) of Example 205 was added to a polymer flocculant (hydroxyethyl cellulose). ) [Dow Chemical Japan Co., Ltd., product name: CELLOSIZE EP-09] 0.4 parts and acrylic polymer dispersant [Japan Lubrizol Co., Ltd., product name: Solsparse 43000] 0.4 parts , Preservative (2-pyridinethiol 1-sodium oxide) [manufactured by Ronza Japan Co., Ltd., product name: sodium omadin] 0.2 parts and preservative (3-iodo-2-propynyl N-butylcarbamate) [Ronza Made by Japan Co., Ltd., Product name: Glycacil 2000] 0.2 parts, 18 parts of glycerin, 0.2 parts of antifoaming agent, 1 part of pH adjuster (10% diluted phosphoric acid solution), specific gravity adjuster (Sodium polytthanstate) (manufactured by SOMETU, product name: SPT) was mixed in an aqueous vehicle consisting of 8 parts and 46.6 parts of water to prepare a reversible thermochromic liquid composition which is an ink for writing tools. ..
A plurality of axially extending inks are impregnated into the ink storage body coated with a polyester sliver with a synthetic resin film, housed in a barrel made of polypropylene resin, and extending axially to the tip of the barrel via a holder. A resin-processed pen body (bullet type) made of an extruded polypropylene resin having an ink lead-out hole was assembled in a connected state, and a cap was attached to manufacture a marking pen. SEBS resin is attached to the top of the cap as a friction member.
When black characters (handwriting) were formed by writing on the paper using the above marking pen, the handwriting was black at room temperature (25 ° C), and when the characters were rubbed with a friction member, the characters became It was decolorized and became colorless, and this state could be maintained unless it was cooled to −20 ° C. or lower. When the paper surface was placed in a freezer and cooled to -20 ° C or lower, the characters turned black again, and this discoloration behavior could be reproduced repeatedly.

Application example 12
Preparation of Reversible Thermal Discoloration Writing Tool (Reversible Thermal Discoloration Marking Pen) Twenty-three parts of the microcapsule pigment (previously cooled to -20 ° C or lower to develop a yellow color) of Example 302 were subjected to a polymer flocculant (hydroxyethyl cellulose). ) [Dow Chemical Japan Co., Ltd., product name: CELLOSIZE WP-09] 0.4 parts and acrylic polymer dispersant [Japan Lubrizol Co., Ltd., product name: Solsparse 43000] 0.4 parts , Preservative (2-pyridinethiol 1-sodium oxide) [manufactured by Ronza Japan Co., Ltd., product name: sodium omadin] 0.2 parts and preservative (3-iodo-2-propynyl N-butylcarbamate) [Ronza Made by Japan Co., Ltd., Product name: Glycacil 2000] 0.2 parts, 30 parts of glycerin, 0.01 part of antifoaming agent, 0.03 part of pH adjuster (10% diluted phosphoric acid solution), and water. It was mixed in an aqueous vehicle consisting of 45.76 parts to prepare a reversible thermochromic liquid composition which is an ink for writing tools.
The above ink for writing tools is impregnated in the ink storage body coated with a polyester sliver with a synthetic resin film, and the pen is housed in a polypropylene resin barrel, and a polyester fiber resin-processed pen (bullet type) is attached to the tip of the barrel. , Assembled in a connected state via a resin holder, attached a cap, and made a marking pen. SEBS resin is attached to the top of the cap as a friction member.
When yellow letters (handwriting) were formed by writing on the paper using the above marking pen, the handwriting was yellow at room temperature (25 ° C), and when the letters were rubbed with a friction member, the letters became It was decolorized and became colorless, and this state could be maintained unless it was cooled to −20 ° C. or lower. When the paper surface was placed in a freezer and cooled to -20 ° C or lower, the characters turned yellow again, and this discoloration behavior could be reproduced repeatedly.

t ₁ complete color development temperature t ₂ color development start temperature t ₃ complete decolorization start temperature t ₄ complete decolorization temperature T ₁ complete decolorization temperature T ₂ decolorization start temperature T ₃ color development start temperature T ₄ complete color development temperature ΔH hysteresis width

Claims

(A) Electron-donating color-developing organic compounds and
(B) A combination of a compound selected from the group consisting of a compound represented by the formula (I) as an electron-accepting compound and a compound represented by the formulas (IIa) to (IIc).
(C) A reversible thermochromic composition comprising (c) a reaction medium that reversibly causes an electron transfer reaction by the component (a) and the component (b) in a specific temperature range.

(During the ceremony,
R 11 is a hydrogen atom, a linear or branched alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an aryl substituted alkyl having 7 to 11 carbon atoms. A group (where the methylene (-CH 2- ) group in the alkyl group may be replaced by an oxy (-O-) group).
R 12 and R 13 each have a linear or branched alkyl group having 1 to 4 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, and an alkenyl group having 6 to 10 carbon atoms, which may be independently substituted with a fluorine atom. It is an aryl group, an aryl substituted alkyl group having 7 to 11 carbon atoms, or a halogen atom.
n11, n12 and n13 are 0 to 2 independently of each other)

(During the ceremony,
R a1 and R a2 are each independently a linear or branched alkyl group having 1 to 17 carbon atoms which may be substituted with a hydrogen atom or a fluorine atom (here, methylene (-in the above-mentioned alkyl group) in the alkyl group. The CH 2- ) group may be replaced by an oxy (-O-) group or a carbonyl (-CO-) group).
R a3 and R a4 are linear or branched alkyl groups having 1 to 4 carbon atoms, alkenyl groups having 2 to 4 carbon atoms, or halogen atoms, which may be independently substituted with fluorine atoms or hydroxy groups, respectively. And
na3 and na4 are 0 to 2 independently of each other)

(During the ceremony,
R b1 and R b2 are independently linear or branched with a hydroxy group, a linear or branched alkoxy group having 1 to 9 carbon atoms, and 1 to 10 carbon atoms which may be substituted with a fluorine atom. It is an alkyl group, an alkoxy group having 2 to 10 carbon atoms, or a halogen atom.
nb1 is 0 to 3,
nb2 is 0 to 2)

(During the ceremony,
R c1 is a hydrogen atom or a linear or branched alkyl group having 1 to 6 carbon atoms.
L is a single bond, a linear or branched alkylene group having 1 to 3 carbon atoms, an aryl substituted alkylene group having 7 to 9 carbon atoms, or an arylene group having 6 to 10 carbon atoms.
R c2 , R c3 and R c4 are independent, linear or branched alkyl groups having 1 to 4 carbon atoms which may be substituted with fluorine atoms, cyclic alkyl groups having 3 to 7 carbon atoms, and carbon atoms. A linear or branched alkoxy group having a number of 1 to 3, an alkenyl group having 2 to 4 carbon atoms, or a halogen atom.
nc2, nc3 and nc4 are 0 to 3 independently of each other)
The composition according to claim 1, comprising a combination of the compound represented by the formula (I) and the compound represented by the formula (IIa) as the component (b).
In formula (I), n11 is 1, n12 and n13 are 0 or 1, respectively.
When n12 and n13 are 0, respectively, R11 is a linear or branched alkyl group having 1 to 3 carbon atoms, or an aryl substituted alkyl group having 7 or 8 carbon atoms, and the hydroxy group is 4 of the benzene ring. It exists in the rank (para rank) and
When n12 and n13 are 1 respectively, R11 is a hydrogen atom, R12 and R13 are alkenyl groups having 2 to 4 carbon atoms, and the hydroxy group is the 4-position (para-position) of the benzene ring, respectively. The composition according to claim 1 or 2, which is present in.
The composition according to any one of claims 1 to 3, wherein in the formula (IIa), at least one of Ra1 and Ra2 is a linear or branched alkyl group having 3 to 9 carbon atoms.
The composition according to claim 2, further comprising the compound represented by the formula (IIb) as the component (b).
In formula (IIb), nb1 is 1, nb2 is 1, R b1 is an isobutyl group, sec-butyl group, or tert-butyl group, R b2 is a hydroxy group, and the hydroxy group is benzene. The composition according to claim 5, which is present at the 2-position (ortho-position) and the 4-position (para-position) of the ring.
The composition according to any one of claims 1 to 6, wherein the content of the compound represented by the formula (IIa) is 30 to 90% by mass based on the total mass of the component (b).
The composition according to claim 5 or 6, wherein the content of the compound represented by the formula (IIb) is 5 to 25% by mass based on the total mass of the component (b).
A reversible thermochromic microcapsule pigment comprising the composition according to any one of claims 1 to 8.
A reversible thermochromic liquid composition comprising the reversible thermochromic microcapsule pigment according to claim 9 and a vehicle.
The tenth aspect of claim 10, which is selected from the group consisting of printing inks, writing tool inks, coating tool inks, stamp inks, inkjet inks, paints, ultraviolet curable inks, paints, cosmetics, and textile coloring liquids. Reversible thermochromic liquid composition.
A solid cursive or solid cosmetic comprising the reversible thermochromic microcapsule pigment according to claim 9 and an excipient.
A resin composition for reversible thermochromic molding, comprising the reversible thermochromic microcapsule pigment according to claim 9 and a molding resin.
A reversible thermochromic molded body obtained by molding the resin composition for reversible thermochromic molding according to claim 13.
A reversible thermochromic laminate comprising a support and a reversible thermochromic layer comprising the reversible thermochromic microcapsule pigment according to claim 9.
A writing instrument containing the reversible thermochromic liquid composition according to claim 10.
The writing tool according to claim 16, further comprising a friction member that discolors the handwriting of the writing tool by frictional heat.