Reversible thermochromic composition and reversible thermochromic microcapsule pigment encapsulating the same

Abstract

To provide a reversible thermochromic microcapsule pigment.SOLUTION: The reversible thermochromic composition comprises (A) an electron-donating color-developing organic compound, (B) a compound represented by formula (1) or (2) as an electron-accepting compound, and (C) a reaction medium which reversibly causes an electron transfer reaction between the components (A) and (B) in a specific temperature range.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a reversible thermochromic composition and a reversible thermochromic microcapsule pigment encapsulating the same. More specifically, the present invention relates to a reversible thermochromic composition that loses color upon temperature increase and develops color upon temperature decrease, and a reversible thermochromic microcapsule pigment encapsulating the same. [Background technology]

[0002] Several proposals have been disclosed in the past regarding reversible thermochromic compositions comprising an electron-donating color-forming organic compound, an electron-accepting compound, and a reaction medium that reversibly induces an electron donor-acceptor reaction in a specific temperature range, and reversible thermochromic microcapsule pigments encapsulating the same (see, for example, Patent Documents 1 to 5). Examples of the electron-accepting compound contained in the reversible thermochromic composition include compounds having an active proton, pseudo-acidic compounds (compounds that are not acids but act as acids in the composition to cause the electron-donating color-forming organic compound to develop color), and compounds having electron vacancies. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 7-11242 [Patent Document 2] Japanese Patent Application Laid-Open No. 2002-53853 [Patent Document 3] Japanese Patent Application Laid-Open No. 2010-106052 [Patent Document 4] Japanese Patent Application Laid-Open No. 2012-229294 [Patent Document 5] JP 2013-10810 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention has been achieved by examining the electron-accepting compound (b) that can be used in a reversible thermochromic composition comprising (a) an electron-donating organic color-forming compound, (b) an electron-accepting compound, and (c) a reaction medium that reversibly induces an electron donor-acceptor reaction between the components (a) and (b) in a specific temperature range. As a result, it has been found that the use of a specific compound can produce a reversible thermochromic function. [Means for solving the problem]

[0005] The present invention relates to a reversible thermochromic composition comprising (i) an electron-donating organic color-forming compound, (ii) a compound represented by formula (1) or (2) as an electron-accepting compound, and (iii) a reaction medium that reversibly induces an electron donating / accepting reaction between the components (i) and (ii) in a specific temperature range. [ka] [ka] (In formulas (1) and (2), R1 represents a halogen atom or a linear or branched alkoxy group having 1 to 8 carbon atoms. R2 represents a substituted or unsubstituted linear or branched alkyl group having 1 to 18 carbon atoms.) Furthermore, in formulas (1) and (2), R1 is a halogen atom and R2 is a substituted or unsubstituted linear or branched alkyl group having 4 to 8 carbon atoms; a reversible thermochromic microcapsule pigment encapsulating the reversible thermochromic composition; a reversible thermochromic liquid composition comprising the reversible thermochromic microcapsule pigment and a vehicle; the reversible thermochromic liquid composition being selected from the group consisting of printing ink, writing ink, applicator ink, stamp ink, inkjet ink, paint, ultraviolet-curable ink, paint, cosmetic, and fiber coloring liquid; The requirements include a reversible thermochromic solid molded article for application comprising a microcapsule pigment and an excipient; the reversible thermochromic solid molded article for application being a solid writing material or a solid cosmetic; a reversible thermochromic molding resin composition comprising the reversible thermochromic microcapsule pigment and a molding resin; a reversible thermochromic molded article obtained by molding the reversible thermochromic molding resin composition; a reversible thermochromic laminate comprising a support and a reversible thermochromic layer comprising the reversible thermochromic microcapsule pigment; a writing instrument containing the writing instrument ink; and a friction member that discolors writing made with the writing instrument due to frictional heat. [Effects of the Invention]

[0006] The present invention provides a reversible thermochromic composition and a reversible thermochromic microcapsule pigment encapsulating the same, which can fully exhibit reversible thermochromic function by using a specific compound as an electron-accepting compound to satisfy the electron-donating reaction with an electron-donating organic color-forming compound, and further by mixing (c) with a reaction medium that reversibly induces the electron-donating reaction between the components (a) and (b) in a specific temperature range. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a graph illustrating the hysteresis characteristics in the color density-temperature curve of a reversibly thermochromic composition that is heat-discolorable. [Figure 2] 1 is a graph illustrating the hysteresis characteristics in the color density-temperature curve of a heat-discolorable, reversible thermochromic composition having color memory properties. DETAILED DESCRIPTION OF THE INVENTION

[0008] The reversible thermochromic composition of the present invention includes a reversible thermochromic composition of the thermal decolorization type (decolorized by heating and colored by cooling) containing at least three essential components: (i) an electron-donating color-forming organic compound, (ii) an electron-accepting compound, and (iii) a reaction medium that determines the temperature at which the color reaction of components (i) and (ii) occurs. The reversible thermochromic composition may be a thermally decolorizable (decolorizes upon heating and develops color upon cooling) reversible thermochromic composition having a relatively small hysteresis width (ΔH) of 1 to 7°C, as described in Japanese Patent Publication Nos. 51-44706, 51-44707, and 1-29398, etc., which undergoes a color change around a predetermined temperature (color change point), exhibiting a decolorized state in a temperature range above the high-temperature color change point and a colored state in a temperature range below the low-temperature color change point, and only one of the two states exists in the room temperature range, and the other state is maintained while the heat or cold required to achieve that state is applied, but returns to the state exhibited in the room temperature range once the application of heat or cold is removed (see Figure 1).

[0009] In addition, the hysteresis width (ΔH) described in JP-B-4-17154, JP-A-7-179777, JP-A-7-33997, JP-A-8-39936, JP-A-2005-1369, JP-A-2008-280523, etc. exhibits a large characteristic of 8°C to 80°C, that is, the shape of the curve plotting the change in color density due to temperature change is such that the temperature increases from a lower side than the discoloration temperature range. The color changes along a path that is significantly different when the temperature is lowered from a temperature higher than the color-changing temperature range, and conversely, when the temperature is lowered from a temperature higher than the color-changing temperature range, and the color is developed in a low temperature range below the complete color-developing temperature (t1) or the color is lost in a high temperature range above the complete decolorization temperature (t4). Reversible thermochromic compositions of the heat-discoloring type (discolored by heating and colored by cooling) that have color memory in a specific temperature range [the temperature range between t2 and t3 (substantially two-phase retention temperature range)] can also be applied (see Figure 2). The hysteresis characteristics of the color density-temperature curve of the reversibly thermochromic composition will be described below. In Figure 2, the vertical axis represents color density and the horizontal axis represents temperature. Changes in color density due to temperature changes progress along the arrows. Here, A represents the density at temperature t4 (hereinafter referred to as the complete decolorization temperature) at which the color is completely removed, B represents the density at temperature t3 (hereinafter referred to as the decolorization onset temperature) at which decolorization begins, C represents the density at temperature t2 (hereinafter referred to as the color development onset temperature), and D represents the density at temperature t1 (hereinafter referred to as the complete color development temperature) at which the color is completely removed. The discoloration temperature range is the temperature range between t1 and t4, and can exhibit either a colored state or a decolored state. The temperature range between t2 and t3, which is the region with the largest difference in color density, is the actual discoloration temperature range. The length of the line segment EF is a measure of the contrast of the discoloration, and the length of the line segment HG passing through the midpoint of the line segment EF is the temperature range indicating the degree of hysteresis (hereinafter referred to as the hysteresis range ΔH). If this ΔH value is small, only one specific state can exist between the two states before and after the discoloration in the room temperature range. Furthermore, if the ΔH value is large, it is easier to maintain each state before and after the discoloration.

[0010] Components (a), (b) and (c) will be specifically explained below. Component (A), that is, the electron-donating organic color-forming compound, is the component that determines the color, and is a compound that donates electrons to component (B), which is the color developer, to develop color. Examples of the electron-donating color-forming organic compound include phthalide compounds, fluoran compounds, styrinoquinoline compounds, diazarhodamine lactone compounds, pyridine compounds, quinazoline compounds, and bisquinazoline compounds, and among these, phthalide compounds and fluoran compounds are preferred. Examples of the phthalide compound include diphenylmethane phthalide compounds, phenylindolyl phthalide compounds, indolyl phthalide compounds, diphenylmethane azaphthalide compounds, phenylindolyl azaphthalide compounds, and derivatives thereof. Among these, phenylindolyl azaphthalide compounds and derivatives thereof are preferred. Examples of fluoran compounds include aminofluoran compounds, alkoxyfluoran compounds, and derivatives thereof. Examples of these compounds are shown below. 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide, 3-(4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)phthalide, 3,3-bis(1-n-butyl-2-methylindol-3-yl)phthalide, 3,3-bis(2-ethoxy-4-diethylaminophenyl)-4-azaphthalide, 3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide, 3-(2-hexyloxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide, 3-[2-ethoxy-4-(N-ethylanilino)phenyl]-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide, 3-(2-acetamido-4-diethylaminophenyl)-3-(1-propylindol-3-yl)-4-azaphthalide, 3,6-bis(diphenylamino)fluoran, 3,6-dimethoxyfluoran, 3,6-di-n-butoxyfluorane, 2-methyl-6-(N-ethyl-Np-tolylamino)fluoran, 3-chloro-6-cyclohexylaminofluoran, 2-methyl-6-cyclohexylaminofluoran, 2-(2-chloroamino)-6-dibutylaminofluoran, 2-(2-chloroanilino)-6-di-n-butylaminofluoran, 2-(3-trifluoromethylanilino)-6-diethylaminofluoran, 2-(3-trifluoromethylanilino)-6-dipentylaminofluoran, 2-(dibenzylamino)-6-diethylaminofluoran, 2-(N-methylanilino)-6-(N-ethyl-Np-tolylamino)fluoran, 1,3-dimethyl-6-diethylaminofluoran, 2-chloro-3-methyl-6-diethylaminofluoran, 2-anilino-3-methyl-6-diethylaminofluoran, 2-anilino-3-methoxy-6-diethylaminofluoran, 2-anilino-3-methyl-6-di-n-butylaminofluoran, 2-anilino-3-methoxy-6-di-n-butylaminofluoran, 2-xylidino-3-methyl-6-diethylaminofluoran, 2-anilino-3-methyl-6-(N-ethyl-Np-tolylamino)fluoran, 1,2-benz-6-diethylaminofluoran, 1,2-Benz-6-(N-ethyl-N-isobutylamino)fluoran, 1,2-benz-6-(N-ethyl-N-isoamylamino)fluoran, 2-(3-methoxy-4-dodecoxystyryl)quinoline, spiro[5H-(1)benzopyrano(2,3-d)pyrimidin-5,1'(3'H)isobenzofuran]-3'-one, 2-(diethylamino)-8-(diethylamino)-4-methyl, spiro[5H-(1)benzopyrano(2,3-d)pyrimidin-5,1'(3'H)isobenzofuran]-3'-one, 2-(di-n-butylamino)-8-(di-n-butylamino)-4-methyl, spiro[5H-(1)benzopyrano(2,3-d)pyrimidin-5,1'(3'H)isobenzofuran]-3'-one, 2-(di-n-butylamino)-8-(diethylamino)-4-methyl, Spiro[5H-(1)benzopyrano(2,3-d)pyrimidin-5,1'(3'H)isobenzofuran]-3'-one, 2-(di-n-butylamino)-8-(N-ethyl-Ni-amylamino)-4-methyl, spiro[5H-(1)benzopyrano(2,3-d)pyrimidin-5,1'(3'H)isobenzofuran]-3'-one, 2-(dibutylamino)-8-(dipentylamino)-4-methyl, 4,5,6,7-tetrachloro-3-[4-(dimethylamino)-2-methoxyphenyl]-3-(1-butyl-2-methyl-1H-indol-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-tetrachloro-3-[4-(diethylamino)-2-ethoxyphenyl]-3-(1-ethyl-2-methyl-1H-indol-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-tetrachloro-3-[4-(diethylamino)-2-ethoxyphenyl]-3-(1-pentyl-2-methyl-1H-indol-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-tetrachloro-3-[4-(diethylamino)-2-methylphenyl]-3-(1-ethyl-2-methyl-1H-indol-3-yl)-1(3H)-isobenzofuranone, 3',6'-bis[phenyl(2-methylphenyl)amino]-spiro[isobenzofuran-1(3H),9'-[9H]xanthen]-3-one, 3',6'-bis[phenyl(3-methylphenyl)amino]-spiro[isobenzofuran-1(3H),9'-[9H]xanthen]-3-one, 3',6'-bis[phenyl(3-ethylphenyl)amino]-spiro[isobenzofuran-1(3H),9'-[9H]xanthen]-3-one, 2,6-bis(2′-ethyloxyphenyl)-4-(4′-dimethylaminophenyl)pyridine, 2,6-bis(2′,4′-diethyloxyphenyl)-4-(4′-dimethylaminophenyl)pyridine, 2-(4′-dimethylaminophenyl)-4-methoxy-quinazoline, 4,4'-(Ethylenedioxy)-bis[2-(4-diethylaminophenyl)quinazoline] The following can be mentioned: In addition to the above-mentioned compounds having a substituent on the phenyl group forming the xanthene ring, fluorans may also be compounds that exhibit a blue or black color and have a substituent on the phenyl group forming the xanthene ring and also have a substituent on the phenyl group forming the lactone ring (for example, an alkyl group such as a methyl group, or a halogen atom such as a chloro group).

[0011] Component (b), ie, the electron accepting compound, is a compound that accepts electrons from component (a) and functions as a developer for component (a). The component (ii) is a 1,3-diphenylurea derivative of formula (1) or (2), which is a non-phenolic electron-accepting compound (developer). [ka] [ka] In formulas (1) and (2), R1 represents a halogen atom or a linear or branched alkoxy group having 1 to 8 carbon atoms. R2 represents a substituted or unsubstituted linear or branched alkyl group having 1 to 18 carbon atoms. In addition, in formula (1) or (2), it is preferable that R1 is a halogen atom or a linear or branched alkoxy group having 1 to 4 carbon atoms, and R2 is a substituted or unsubstituted linear or branched alkyl group having 3 to 12 carbon atoms, and it is more preferable that R1 is a halogen atom, and R2 is a substituted or unsubstituted linear or branched alkyl group having 4 to 8 carbon atoms.

[0012] Examples of the halogen atom in R1 of formula (1) or (2) include a fluorine atom, a chlorine atom, and a bromine atom, with a fluorine atom and a chlorine atom being preferred. Examples of the linear or branched alkoxy group having 1 to 8 carbon atoms in R1 include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an isopropoxy group, an isobutoxy group, a sec-butoxy group, and a t-butoxy group, and a linear or branched alkoxy group having 1 to 4 carbon atoms is preferred. Examples of the substituted or unsubstituted linear or branched alkyl group having 1 to 18 carbon atoms in R2 include a butyl group, an isobutyl group, a sec-butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group, and a butyl group, a pentyl group, and a hexyl group are preferred. When R2 is a linear or branched alkyl group having 4 to 8 carbon atoms and having a substituent, examples of the substituent include halogen, a hydroxy group, a carboxy group, a sulfo group, an alkylthio group, an alkylamino group, and an ester group, and a fluorine atom, a chlorine atom, and a hydroxy group are preferred. The number and positions of the substituents are not particularly limited.

[0013] Specific examples of the diphenylurea derivatives of the formula (1) or (2) include the following compounds. [ka]

[0014] In addition to the component (b), the composition may further contain a known electron-accepting compound. Examples of the electron-accepting compound include compounds selected from a group of compounds having an active proton, a group of pseudo-acidic compounds (a group of compounds that are not acids but act as an acid in the reversible thermochromic composition to cause component (A) to develop color), and a group of compounds having an electron vacancy. Examples of compounds having an active proton include compounds having a phenolic hydroxyl group and derivatives thereof, carboxylic acids and derivatives thereof, acidic phosphate esters and derivatives thereof, azole compounds and derivatives thereof, 1,2,3-triazole and derivatives thereof, cyclic carbosulfimides, halohydrins having 2 to 5 carbon atoms, sulfonic acids and derivatives thereof, inorganic acids, etc. As the carboxylic acids and derivatives thereof, aromatic carboxylic acids and derivatives thereof, or aliphatic carboxylic acids having 2 to 5 carbon atoms and derivatives thereof are preferred. Examples of the pseudo-acidic compounds include metal salts of compounds having a phenolic hydroxyl group, metal salts of carboxylic acids, metal salts of acidic phosphate esters, metal salts of sulfonic acids, aromatic carboxylic acid anhydrides, aliphatic carboxylic acid anhydrides, mixed anhydrides of aromatic carboxylic acids and sulfonic acids, cycloolefin dicarboxylic acid anhydrides, urea and its derivatives, thiourea and its derivatives, guanidine and its derivatives, and halogenated alcohols. Examples of compounds having electron vacancies include borates, borate esters, inorganic salts, and the like. Compounds having a phenolic hydroxyl group include a wide range of compounds, from monophenol compounds to polyphenol compounds, and further include bisphenol compounds, trisphenol compounds, phenol-aldehyde condensation resins, etc. The compound having a phenolic hydroxyl group preferably has at least two benzene rings. In addition, the compound having a phenolic hydroxyl group may have a substituent such as an alkyl group, an aryl group, an acyl group, an alkoxycarbonyl group, a carboxyl group and its ester or amide group, or a halogen atom. Examples of metals contained in metal salts of compounds having a phenolic hydroxyl group include sodium, potassium, calcium, zinc, zirconium, aluminum, magnesium, nickel, cobalt, tin, copper, iron, vanadium, titanium, lead, and molybdenum.

[0015] Examples of known electron-accepting compounds are shown below. Examples of compounds having one phenolic hydroxyl group include: phenol, o-cresol, m-cresol, p-cresol, 4-ethylphenol, 4-n-propylphenol, 4-n-butylphenol, 2-tert-butylphenol, 3-tert-butylphenol, 4-tert-butylphenol, 4-n-pentylphenol, 4-tert-pentylphenol, 4-n-octylphenol, 4-tert-octylphenol, 4-n-nonylphenol, 4-n-dodecylphenol, 3-n-pentadecylphenol, 4-n-stearylphenol, 1-(4-hydroxyphenyl)decan-1-one, 4-chlorophenol, 4-bromophenol, 4-trifluoromethylphenol, 4-methylthiophenol, 4-nitrophenol, 2-phenylphenol, 4-phenylphenol, 2-benzylphenol, 2-benzyl-4-chlorophenol, 4-cumylphenol, 4-hydroxybenzophenone, 4-chloro-4′-hydroxybenzophenone, 4-fluoro-4′-hydroxybenzophenone, 4-cyclohexylphenol, 2-hydroxybenzyl alcohol, 3-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol, 4-(2-hydroxyethyl)phenol, 3-methoxyphenol, 4-ethoxyphenol, 4-n-propoxyphenol, 4-n-butoxyphenol, 4-n-heptyloxyphenol, 4-(2-methoxyethyl)phenol, α-naphthol, β-naphthol, 2,3-dimethylphenol, 2,4-dimethylphenol, 2,6-dimethylphenol, 2,6-di-tert-butylphenol, 2,4-dichlorophenol, 2,4-difluorophenol, thymol, 3-methyl-4-methylthiophenol, 2-tert-butyl-5-methylphenol, 2,6-bis(hydroxymethyl)-4-methylphenol, 2,3,5-trimethylphenol, 2,6-bis(hydroxymethyl)-4-tert-octylphenol, 6-hydroxy-1,3-benzoxathiol-2-one, 2,4-bis(phenylsulfonyl)phenol, 2,4-bis(phenylsulfonyl)-5-methylphenol, 2,4-bis(4-methylphenylsulfonyl)phenol, 2-phenylphenol, 4-phenylphenol, 2,6-diphenylphenol, 3-benzylbiphenyl-2-ol, 3,5-dibenzylbiphenyl-4-ol, 4-cyano-4′-hydroxybiphenyl, 1-hydroxybenzotriazole, 1-hydroxy-5-methylbenzotriazole, 1-hydroxy-5-chlorobenzotriazole, 1-hydroxy-5-methoxybenzotriazole, 1-hydroxy-4-benzoylaminobenzotriazole, 1-hydroxy-4,5,6,7-tetrachlorobenzotriazole, 1,4-hydroxybenzotriazole, 1-hydroxy-5-nitrobenzotriazole, 1-hydroxy-5-phenylbenzotriazole, 1-hydroxy-5-benzylbenzotriazole, 1-hydroxy-5-ethylbenzotriazole, 1-hydroxy-5-n-octylbenzotriazole, 1-hydroxy-5-n-butylbenzotriazole, n-Butyl 4-hydroxybenzoate, n-Octyl 4-hydroxybenzoate, 4-Hydroxybenzoic acid 2-heptadecafluorooctylethane, benzyl 4-hydroxybenzoate, 4-hydroxybenzoic acid benzyl ester, o-methylbenzyl 4-hydroxybenzoate, m-methylbenzyl 4-hydroxybenzoate, p-methylbenzyl 4-hydroxybenzoate, p-ethylbenzyl 4-hydroxybenzoate, p-propylbenzyl 4-hydroxybenzoate, p-tert-butylbenzyl 4-hydroxybenzoate, phenylethyl 4-hydroxybenzoate, 4-hydroxybenzoic acid-o-methylphenylethyl ester, m-Methylphenylethyl 4-hydroxybenzoate, p-methylphenylethyl 4-hydroxybenzoate, p-Ethylphenylethyl 4-hydroxybenzoate, p-propylphenylethyl 4-hydroxybenzoate, p-tert-butylphenylethyl 4-hydroxybenzoate Examples include:

[0016] Examples of compounds having two phenolic hydroxyl groups include: Resorcinol, 2-methylresorcinol, 4-n-hexylresorcinol, 4-n-octylresorcinol, 4-tert-octylresorcinol, 4-benzoylresorcinol, 4-nitroresorcinol, β-methyl resorcylate, β-benzyl resorcylate, 2-chloro-4-pentanoylresorcinol, 6-chloro-4-pentanoylresorcinol, 2-chloro-4-hexanoylresorcinol, 6-chloro-4-hexanoylresorcinol, 2-chloro-4-propanoylresorcinol, 6-chloro-4-propanoylresorcinol, 2,6-dichloro-4-propanoylresorcinol, 6-fluoro-4-propanoylresorcinol, 2-chloro-4-phenylacetylresorcinol, 6-chloro-4-phenylacetylresorcinol, 2-chloro-4-β-phenylpropanoylresorcinol, 6-chloro-4-β-phenylpropanoylresorcinol, 2-chloro-4-phenoxyacetylresorcinol, 6-chloro-4-phenoxyacetylresorcinol, 4-benzoyl-2-chlororesorcinol, 6-chloro-4-m-methylbenzoylresorcinol, 4-[1',3',4',9'a-tetrahydro-6'-hydroxyspiro(cyclohexane-1,9'-[9H]-xanthene)-4'a-[2H]-yl]-1,3-benzenediol, hydroquinone, methylhydroquinone, trimethylhydroquinone, Catechol, 4-tert-butylcatechol, 1,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,4-dihydroxybenzophenone, 4,4′-dihydroxybenzophenone, 2,4-dihydroxy-2′-methylbenzophenone, 2,4-dihydroxy-3′-methylbenzophenone, 2,4-dihydroxy-4′-methylbenzophenone, 2,4-dihydroxy-4′-ethylbenzophenone, 2,4-dihydroxy-4′-n-propylbenzophenone, 2,4-dihydroxy-4′-isopropylbenzophenone, 2,4-dihydroxy-4′-n-butylbenzophenone, 2,4-dihydroxy-4′-isobutylbenzophenone, 2,4-dihydroxy-4′-tert-butylbenzophenone, 2,4-dihydroxy-4′-n-pentylbenzophenone, 2,4-dihydroxy-4′-n-hexylbenzophenone, 2,4-dihydroxy-4′-n-heptylbenzophenone, 2,4-dihydroxy-4′-n-octylbenzophenone, 2,4-dihydroxy-4′-n-decylbenzophenone, 2,4-dihydroxy-2′,3′-dimethylbenzophenone, 2,4-dihydroxy-2′,4′-dimethylbenzophenone, 2,4-dihydroxy-2′,5′-dimethylbenzophenone, 2,4-dihydroxy-2′,6′-dimethylbenzophenone, 2,4-dihydroxy-3′,4′-dimethylbenzophenone, 2,4-dihydroxy-3′,5′-dimethylbenzophenone, 2,4-dihydroxy-2′,4′,6′-trimethylbenzophenone, 2,4-dihydroxy-2′-methoxybenzophenone, 2,4-dihydroxy-3′-methoxybenzophenone, 2,4-dihydroxy-4′-methoxybenzophenone, 2,4-dihydroxy-2′-ethoxybenzophenone, 2,4-dihydroxy-4′-ethoxybenzophenone, 2,4-dihydroxy-4′-n-propoxybenzophenone, 2,4-dihydroxy-4′-isopropoxybenzophenone, 2,4-dihydroxy-4′-n-butoxybenzophenone, 2,4-dihydroxy-4′-isobutoxybenzophenone, 2,4-dihydroxy-4′-n-pentyloxybenzophenone, 2,4-dihydroxy-4′-n-hexyloxybenzophenone, 2,4-dihydroxy-4′-n-heptyloxybenzophenone, 2,4-dihydroxy-4′-n-octyloxybenzophenone, 2,4-dihydroxy-4′-n-nonyloxybenzophenone, 2,4-dihydroxy-2′,3′-dimethoxybenzophenone, 2,4-dihydroxy-2′,4′-dimethoxybenzophenone, 2,4-dihydroxy-2′,5′-dimethoxybenzophenone, 2,4-dihydroxy-2′,6′-dimethoxybenzophenone, 2,4-dihydroxy-3′,4′-dimethoxybenzophenone, 2,4-dihydroxy-3′,5′-dimethoxybenzophenone, 2,4-dihydroxy-3′,4′-diethoxybenzophenone, 2,4-dihydroxy-2′,3′,4′-trimethoxybenzophenone, 2,4-dihydroxy-2′,3′,6′-trimethoxybenzophenone, 2,4-dihydroxy-3′,4′,5′-trimethoxybenzophenone, 2,4-Dihydroxy-3',4',5'-triethoxybenzophenone Examples include:

[0017] Further, examples of bisphenol compounds include: 1,1-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl) n-butane, 1,1-bis(4-hydroxyphenyl) n-pentane, 1,1-bis(4-hydroxyphenyl) n-hexane, 1,1-bis(4-hydroxyphenyl) n-heptane, 1,1-bis(4-hydroxyphenyl) n-octane, 1,1-bis(4-hydroxyphenyl)n-nonane, 1,1-bis(4-hydroxyphenyl) n-decane, 1,1-bis(4-hydroxy-3-methylphenyl)decane, 1,1-bis(4-hydroxyphenyl) n-dodecane, 1,1-bis(4-hydroxyphenyl)-2-methylpropane, 1,1-bis(4-hydroxyphenyl)-3-methylbutane, 1,1-bis(4-hydroxyphenyl)-3-methylpentane, 1,1-bis(4-hydroxyphenyl)-2,3-dimethylpentane, 1,1-bis(4-hydroxyphenyl)-2-ethylbutane, 1,1-bis(4-hydroxyphenyl)-2-ethylhexane, 1,1-bis(4-hydroxyphenyl)-3,7-dimethyloctane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 1,1-bis(4-hydroxy-3-methyl)cyclohexane, diphenolic acid, 1-phenyl-1,1-bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl) n-butane, 2,2-bis(4-hydroxyphenyl) n-pentane, 2,2-bis(4-hydroxyphenyl)n-hexane, 2,2-bis(4-hydroxyphenyl) n-heptane, 2,2-bis(4-hydroxyphenyl) n-octane, 2,2-bis(4-hydroxyphenyl)n-nonane, 2,2-bis(4-hydroxyphenyl) n-decane, 2,2-bis(4-hydroxyphenyl) n-dodecane, 2,2-bis(4-hydroxyphenyl)-6,10,14-trimethylpentadecane, 1-phenyl-1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)methylpropionate, 2,2-bis(4-hydroxyphenyl)butylpropionate, 2,2-bis(4-hydroxy-3-methylphenyl)methylpropionate, 2,2-bis(4-hydroxyphenyl)ethyl propionate, 2,2-bis(4-hydroxyphenyl)-4-methylpentane, 2,2-bis(4-hydroxyphenyl)-4-methylhexane, 2,2-bis(4-hydroxyphenyl)hexafluoropropane, 2,2-bis(3,5-dihydroxymethyl-4-hydroxyphenyl)hexafluoropropane, 2,2-bis(4-hydroxy-3-methylphenyl)propane, 2,2-bis(4-hydroxy-3-methylphenyl)butane, 2,2-bis(4-hydroxy-3-isopropylphenyl)propane, 2,2-bis(3-sec-butylphenyl-4-hydroxy)propane, 2,2-bis(4-hydroxy-3-phenylphenyl)propane, 2,2-bis(3-tert-butyl-4-hydroxyphenyl)propane, 2,2-bis(3-fluoro-4-hydroxyphenyl)propane, 2,2-bis(3,5-dihydroxymethyl-4-hydroxyphenyl)propane, 9,9-bis(4-hydroxy-3-methylphenyl)fluorene, 1,3-bis[2-(4-hydroxyphenyl)-2-propyl]benzene, 1,4-bis[2-(4-hydroxyphenyl)-2-propyl]benzene, 3,3-bis(4-hydroxyphenyl)oxindole, 3,3-bis(4-hydroxy-3-methylphenyl)oxindole, bis(2-hydroxyphenyl)methane, bis(2-hydroxy-5-methylphenyl)methane, bis(2-hydroxy-3-hydroxymethyl-5-methyl)methane, 4,4'-[1,4-phenylenebis(1-methylethylidene)]bis(2-methylphenol), 1,1-bis(4-hydroxy-3-phenylphenyl)cyclohexane, 3,3-ethyleneoxydiphenol, 1,4-bis(4-hydroxybenzoate)-3-methylbenzene, 4,4"-dihydroxy-3"-methyl-p-terphenyl, 4,4″-dihydroxy-3″-isopropyl-p-terphenyl, 2,2-dimethyl-1,3-bis(4-hydroxybenzoyloxy)propane, 2,2′-biphenol, 4,4′″-dihydroxy-p-quaterphenyl, 4,4-dihydroxydiphenyl ether, Bis(4-hydroxyphenylthioethyl) ether bis(4-hydroxyphenyl) sulfone, 4-benzyloxy-4′-hydroxydiphenyl sulfone, 4-(4-methylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(4-ethylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(4-n-propylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(4-isopropylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(4-n-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(4-isobutylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(4-sec-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(4-tert-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(3-methylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(3-ethylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(3-n-propylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(3-isopropylbenzyloxy)-4′-dihydroxyphenyl sulfone, 4-(3-n-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(3-isobutylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(3-sec-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(3-tert-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-methylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-ethylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-n-propylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-isopropylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-n-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-isobutylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-sec-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-tert-butylbenzyloxy)-4′-hydroxydiphenyl sulfone, 2,4′-dihydroxydiphenyl sulfone, 3,4′-dihydroxydiphenyl sulfone, 4-hydroxydiphenyl sulfone, 4-methyl-4'-hydroxyphenyl sulfone, 4-ethyl-4′-hydroxydiphenyl sulfone, 4-n-propyl-4′-hydroxydiphenyl sulfone, 4-isopropyl-4′-hydroxydiphenyl sulfone, 4-chloro-4′-hydroxydiphenyl sulfone, 4-fluoro-4′-hydroxydiphenyl sulfone, 4-chloro-2-methyl-4′-hydroxydiphenyl sulfone, 4-methoxy-4′-hydroxydiphenyl sulfone, 4-ethoxy-4′-hydroxydiphenyl sulfone, 4-n-propoxy-4′-hydroxydiphenyl sulfone, 4-isopropoxy-4′-hydroxydiphenyl sulfone, 4-n-butoxy-4′-hydroxydiphenyl sulfone, 4-isobutoxy-4′-hydroxydiphenyl sulfone, 4-sec-butoxy-4′-hydroxydiphenyl sulfone, 4-tert-butoxy-4′-hydroxydiphenyl sulfone, 4-n-pentyloxy-4′-hydroxydiphenyl sulfone, 4-isopentyloxy-4′-hydroxydiphenyl sulfone, 4-(1-propenyloxy)-4′-hydroxydiphenyl sulfone, 4-(2-propenyloxy)-4′-hydroxydiphenyl sulfone, 4-benzyloxy-4′-hydroxydiphenyl sulfone, 4-(β-phenoxyethoxy)-4′-hydroxydiphenyl sulfone, 4-(β-phenoxypropoxyl)-4′-hydroxydiphenyl sulfone, bis(2-allyl-4-hydroxydiphenyl) sulfone, bis[4-hydroxy-3-(2-propenyl)phenyl]sulfone, bis(3,5-dibromo-4-hydroxyphenyl) sulfone, bis(3,5-dichloro-4-hydroxyphenyl) sulfone, bis(3-phenyl-4-hydroxyphenyl) sulfone, bis(4-hydroxy-3-n-propylphenyl) sulfone, bis(4-hydroxy-3-methylphenyl) sulfone, 3,4-dihydroxydiphenyl sulfone, 3',4'-dihydroxy-4-methyldiphenyl sulfone, 3,4,4′-trihydroxydiphenyl sulfone, bis(3,4-dihydroxyphenyl) sulfone, 2,3,4-trihydroxydiphenyl sulfone, 4-isopropoxy-4′-hydroxydiphenyl sulfone, 4-n-propoxy-4′-hydroxydiphenyl sulfone, 4-allyloxy-4′-hydroxydiphenyl sulfone, 4-benzyloxy-4′-hydroxydiphenyl sulfone, 4-(2-propenyloxy)-4′-hydroxydiphenyl sulfone, 3-benzyl-4-benzyloxy-4′-hydroxydiphenyl sulfone, 3-phenethyl-4-phenethyloxy-4′-hydroxydiphenyl sulfone, 3-methylbenzyl-4-methylbenzyloxy-4′-hydroxydiphenyl sulfone, 4-benzyloxy-3′-benzyl-4′-hydroxydiphenyl sulfone, 4-phenethyloxy-3′-phenethyl-4′-hydroxydiphenyl sulfone, 4-methylbenzyloxy-3′-methylbenzyl-4′-hydroxydiphenyl sulfone, α,α′-bis{4-(p-hydroxyphenylsulfone)phenoxy}-p-xylene, 4,4′-{oxybis(ethylene oxide-p-phenylene sulfonyl)}diphenol, Bis(4-hydroxyphenyl) sulfide, bis(4-hydroxy-3-methylphenyl) sulfide, bis(3,5-dimethyl-4-hydroxyphenyl) sulfide, bis(3-ethyl-4-hydroxyphenyl) sulfide, bis(3,5-diethyl-4-hydroxyphenyl) sulfide, bis(4-hydroxy-3-n-propylphenyl) sulfide, bis(3,5-di-n-propyl-4-hydroxyphenyl) sulfide, bis(3-tert-butyl-4-hydroxyphenyl) sulfide, bis(3,5-di-tert-butyl-4-hydroxyphenyl) sulfide, bis(4-hydroxy-3-n-pentylphenyl) sulfide, bis(3-n-hexyl-4-hydroxyphenyl) sulfide, bis(3-n-heptyl-4-hydroxyphenyl) sulfide, bis(5-tert-octyl-2-hydroxyphenyl) sulfide, bis(2-hydroxy-3-tert-octylphenyl) sulfide, bis(2-hydroxy-5-n-octyl-phenyl) sulfide, bis(5-chloro-2-hydroxyphenyl) sulfide, bis(3-cyclohexyl-4-hydroxyphenyl) sulfide, bis(4-hydroxyphenylthioethoxy)methane, 1,5-(4-hydroxyphenylthio)-3-oxypentane, 1,8-bis(4-hydroxyphenylthio)-3,6-dioxaoctane Examples include:

[0018] Examples of compounds having three phenolic hydroxyl groups include pyrogallol, phloroglucinol, phloroglucinolcarboxylic acid, gallic acid, octyl gallate, and dodecyl gallate.

[0019] Further examples of trisphenol compounds include: 4,4′,4″-methylidynetrisphenol, 4,4′,4″-methylidynetris(2-methylphenol), 4,4'-[(2-hydroxyphenyl)methylene]bis(2,3,5-trimethylphenol), 4,4'-[(4-hydroxyphenyl)methylene]bis(2-methylphenol), 4,4'-[(4-hydroxyphenyl)methylene]bis(2,6-dimethylphenol), 4,4'-[(4-hydroxy-3-methoxyphenyl)methylene]bisphenol, 4,4'-[(4-hydroxyphenyl)methylene]bis(2-cyclohexyl-5-methylphenol), 4,4′,4″-ethylidynetrisphenol, 4,4′,4″-ethylidinetris(2-methylphenol), 4,4'-[(2-hydroxyphenyl)methylene]bis(2-cyclohexyl-5-methylphenol), 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenol, 2,4-bis[(2-hydroxy-5-methylphenyl)methyl]-6-cyclohexylphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}methylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}propylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}butylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}pentylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}hexylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}heptylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}isobutylidene]bisphenol, 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}neopentylidene]bisphenol, 2,2'-[1-{4-[1-(2-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bisphenol, 3,3′-[1-{4-[1-(3-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bisphenol, 4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-fluorophenol), 4,4'-[1-{4-[1-(3-chloro-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-chlorophenol), 4,4'-[1-{4-[1-(3-bromo-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-bromophenol), 4,4'-[1-{4-[1-(4-hydroxy-3-methylphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-methylphenol), 4,4'-[1-{4-[1-(3-ethyl-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-ethylphenol), 4,4'-[1-{4-[1-(3-tert-butyl-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-tert-butylphenol), 4,4'-[1-{4-[1-(4-hydroxy-3-trifluoromethylphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-trifluoromethylphenol), 1,1-bis(4-hydroxyphenyl)-4-(4-hydroxy-α-ethyl)benzylcyclohexane, 4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bisphenol, 4,4'-[(3-hydroxyphenyl)methylene]bis(2,6-dimethylphenol), 2,2'-[(4-hydroxyphenyl)methylene]bis(3,5-dimethylphenol), 4,4'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(2,6-dimethylphenol), 2,2'-[(2-hydroxyphenyl)methylene]bis(3,5,6-trimethylphenol), 4,4'-[(3-hydroxyphenyl)methylene]bis(2,3,6-trimethylphenol), 4,4'-[(4-hydroxyphenyl)methylene]bis(2,3,6-trimethylphenol), 4,4'-[(3-hydroxyphenyl)methylene]bis(2-cyclohexyl-5-methylphenol), 4,4'-[(4-hydroxyphenyl-3-methoxy)methylene]bis(2-cyclohexyl-5-methylphenol), 1,1-bis(4-hydroxyphenyl)-4-hydroxyphenylcyclohexane, 4,4'-[3-(5-cyclohexyl-4-hydroxy-2-methylphenyl)-3-phenyl)propylidene]bis(2-cyclohexyl-5-methylphenol), 4,4'-[(2-hydroxyphenyl)methylene]bis(2-methylphenol), 2,4′,4″-methylidynetrisphenol, 4,4'-[(2-hydroxyphenyl)methylene]bis(3-methylphenol), 4,4'-[4-(4-hydroxyphenyl)-sec-butylidene]bis(4-hydroxyphenol), 2,2'-[(3-hydroxyphenyl)methylene]bis(3,5-dimethylphenol), 4,4'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(2,5-dimethylphenol), 4,4'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(2,6-dimethylphenol), 2,2'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(3,5-dimethylphenol), 2,2'-[(3-hydroxy-4-methoxyphenyl)methylene]bis(3,5-dimethylphenol), 2,2'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(3,5-dimethylphenol), 4,4'-[(2-hydroxyphenyl)methylene]bis(2-isopropylphenol), 4,4'-[(3-hydroxyphenyl)methylene]bis(2-isopropylphenol), 4,4'-[(4-hydroxyphenyl)methylene]bis(2-isopropylphenol), 2,2'-[(3-hydroxyphenyl)methylene]bis(3,5,6-trimethylphenol), 2,2'-[(4-hydroxyphenyl)methylene]bis(3,5,6-trimethylphenol), 2,2'-[(4-3-ethoxy-4-hydroxyphenyl)methylene]bis(3,5-dimethylphenol), 1,1-bis(4-hydroxy-3-methylphenyl)-4-(4-hydroxyphenyl)cyclohexane, 4,4'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(2-isopropylphenol), 4,4'-[(3-hydroxy-4-methoxyphenyl)methylene]bis(2-isopropylphenol), 4,4'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(2-isopropylphenol), 2,2'-[(2-hydroxy-3-methoxyphenyl)methylene]bis(3,5,6-trimethylphenol), 2,2'-[(3-hydroxy-4-methoxyphenyl)methylene]bis(3,5,6-trimethylphenol), 2,2'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(3,5,6-trimethylphenol), 4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(2-isopropylphenol), 2,2'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(3,5,6-trimethylphenol), 4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(2,3,6-trimethylphenol), 1,1-bis(3,5-dimethyl-4-hydroxyphenyl)-4-(4-hydroxyphenyl)cyclohexane, 4,4'-[(4-hydroxy-3-methoxyphenyl)methylene]bis(2-tert-butyl-5-methylphenol), 4,4'-[(2-hydroxyphenyl)methylene]bis(2-cyclohexylphenol), 4,4'-[(3-hydroxyphenyl)methylene]bis(2-cyclohexylphenol), 4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(2-tert-butyl-6-methylphenol), 4,4'-[(3-methoxy-2-hydroxyphenyl)methylene]bis(2-cyclohexylphenol), 4,4'-[(3-hydroxy-4-methoxyphenyl)methylene]bis(2-cyclohexylphenol), 4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-tert-butylphenol), 4,4'-[1-{4-[1-(3,5-dimethyl-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2,6-dimethylphenol), 4,4'-[(3-ethoxy-4-hydroxyphenyl)methylene]bis(2-cyclohexyl-5-methylphenol), 4,4'-[(3-cyclohexyl-4-hydroxyphenyl)ethylidene]bis(2-cyclohexylphenol), 4,4'-[(5-cyclohexyl-4-hydroxy-2-methoxyphenyl)ethylidene]bis(2-cyclohexyl-5-methylphenol), 4,4'-[1-{4-[1-(3-cyclohexyl-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-cyclohexylphenol), 4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bisphenol, 4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2-methylphenol), 4,4'-[1-{4-[1-(3-fluoro-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis(2,6-dimethylphenol), 2,6-bis[(5-fluoro-2-hydroxyphenyl)methyl]-4-methylphenol, 2,6-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl]-4-methylphenol, 2,6-bis[(4-hydroxyphenyl)methyl]-4-methylphenol, 2,6-bis[(4-hydroxyphenyl)methyl]-4-ethylphenol, 2,4-bis[(4-hydroxy-3-methylphenyl)methyl]-6-methylphenol, 2,6-bis[(4-hydroxy-3-methylphenyl)methyl]-4-methylphenol, 2,6-bis[(4-hydroxy-3-methylphenyl)methyl]-4-ethylphenol, 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-ethylphenol, 2,6-bis[(3,5-dimethyl-2-hydroxyphenyl)methyl]-4-methylphenol, 2,6-bis[(2,4-dimethyl-6-hydroxyphenyl)methyl]-4-methylphenol, 2,4-bis[(4-hydroxyphenyl)methyl]-6-cyclohexylphenol, 2,6-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-3,4-dimethylphenol, 2,6-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-4-ethylphenol, 2,6-bis[(4-hydroxy-2,3,6-trimethylphenyl)methyl]-4-methylphenol, 2,4-bis[(4-hydroxy-3-methylphenyl)methyl]-6-cyclohexylphenol, 2,6-bis[(4-hydroxy-3-methylphenyl)methyl]-4-cyclohexylphenol, 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-cyclohexylphenol, 2,6-bis[(4-hydroxy-2,3,5-trimethylphenyl)methyl]-4-ethylphenol, 2,4-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-6-cyclohexylphenol, 4,4′,4″-methylidynetris(2,6-dimethylphenol), α-(4-hydroxy-3-methylphenyl)-α,α′-bis(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene, α′-(4-hydroxy-3-methylphenyl)-α,α-bis(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene, α,α-bis(4-hydroxy-3-methylphenyl)-α′-(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene, α,α′-bis(4-hydroxy-3-methylphenyl)-α-(4-hydroxyphenyl)-1-ethyl-4-isopropylbenzene, 1,1-bis(4-hydroxyphenyl)-4-[1-(4-hydroxyphenyl)-1-methylpropyl]cyclohexane, 2,6-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl]-4-ethylphenol, 1,1′-bis(4-hydroxyphenyl)-4-[1-(4-hydroxyphenyl)propyl]cyclohexane, 1,1′-bis(4-hydroxy-3-methylphenyl)-4-[1-(4-hydroxyphenyl)propyl]cyclohexane, 1,1′-bis(3,5-dimethyl-4-hydroxyphenyl)-4-[1-(4-hydroxyphenyl)propyl]cyclohexane, 1-(4-hydroxyphenyl)-1-[4,4-bis(4-hydroxyphenyl)cyclohexyl]-4-isopropylcyclohexane, 4,4'-[3-(2,5-dimethyl-4-hydroxyphenyl)butylene]bis(2,5-dimethylphenol), 1,3,5-tri(4-hydroxy-3-phenylphenyl)adamantane, 1,3,5-tri(3-cyclohexyl-4-hydroxyphenyl)adamantane, 2,4-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl]-6-cyclohexylphenol, 2,6-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-4-cyclohexylphenol, 2,4-bis[(3-cyclohexyl-4-hydroxyphenyl)methyl]-6-methylphenol, 2,4-bis[(4-hydroxy-2,3,5-trimethylphenyl)methyl]-6-cyclohexylphenol, 2,6-bis[(5-fluoro-2-hydroxyphenyl)methyl]-4-fluorophenol, 2,6-bis[(3-fluoro-4-hydroxyphenyl)methyl]-4-fluorophenol, 2,4-bis[(3-fluoro-4-hydroxyphenyl)methyl]-6-methylphenol, 4,4'-[3-(5-cyclohexyl-4-hydroxy-2-methylphenyl)-3-biphenylpropylidene]bis(5-cyclohexyl-2-methylphenol), 4,4'-[3-(2,5-dimethyl-4-hydroxyphenyl)-3-phenylpropylidene]bis(2,5-dimethylphenol), 2,4-bis[(2,5-dimethyl-4-hydroxyphenyl)methyl]-6-methylphenol, 1,1,2-tris(4-hydroxyphenyl)ethane, 1,1,3-tris(4-hydroxyphenyl)propane, 1,1,4-tris(4-hydroxyphenyl)butane, 1,2,2-tris(4-hydroxyphenyl)propane, 1,2,2-tris(4-hydroxyphenyl)butane, 1,2,2-tris(4-hydroxyphenyl)pentane, 1,2,2-tris(4-hydroxyphenyl)hexane, 1,2,2-tris(4-hydroxyphenyl)heptane, 1,2,2-tris(4-hydroxyphenyl)octane, 1,2,2-tris(4-hydroxyphenyl)-3-methylbutane 1,2,2-tris(4-hydroxyphenyl)-3,3-dimethylbutane, 1,2,2-tris(4-hydroxyphenyl)-4,4-dimethylpentane, 1,3,3-tris(4-hydroxyphenyl)butane, 1,3,3-tris(4-hydroxyphenyl)pentane, 1,3,3-tris(4-hydroxyphenyl)hexane, 1,3,3-tris(4-hydroxyphenyl)heptane, 1,3,3-tris(4-hydroxyphenyl)octane, 1,3,3-tris(4-hydroxyphenyl)nonane, 1,4,4-tris(4-hydroxyphenyl)pentane, 1,4,4-tris(4-hydroxyphenyl)hexane, 1,4,4-tris(4-hydroxyphenyl)heptane, 1,4,4-tris(4-hydroxyphenyl)octane, 1,4,4-tris(4-hydroxyphenyl)nonane, 1,4,4-tris(4-hydroxyphenyl)decane, 1,2,2-tris(2-hydroxyphenyl)propane, 1,1,2-tris(3-hydroxyphenyl)propane, 1-(4-hydroxyphenyl)-2,2-bis(2-hydroxyphenyl)propane, 1,2,2-tris(3-fluoro-4-hydroxyphenyl)propane, 1,2,2-tris(3-chloro-4-hydroxyphenyl)propane, 1,2,2-tris(3-bromo-4-hydroxyphenyl)propane, 2,2-bis(3-ethyl-4-hydroxyphenyl)-1-(4-hydroxyphenyl)propane, 2,2-bis(3-tert-butyl-4-hydroxyphenyl)-1-(4-hydroxyphenyl)propane, 2,2-bis(2-hydroxy-3-biphenylyl)-1-(4-hydroxyphenyl)propane, 2,2-bis(3-trifluoromethyl-4-hydroxyphenyl)-1-(4-hydroxyphenyl)propane, 2-(3-methyl-4-hydroxyphenyl)-1,2-bis(4-hydroxyphenyl)propane, 1-(3-methyl-4-hydroxyphenyl)-2,2-bis(4-hydroxyphenyl)propane, 3-(3-methyl-4-hydroxyphenyl)-1,3-bis(4-hydroxyphenyl)butane, 1-(3-methyl-4-hydroxyphenyl)-3,3-bis(4-hydroxyphenyl)butane, 4-(3-methyl-4-hydroxyphenyl)-1,4-bis(4-hydroxyphenyl)pentane, 1-(3-methyl-4-hydroxyphenyl)-4,4-bis(4-hydroxyphenyl)pentane, 1,2-bis(3-methyl-4-hydroxyphenyl)-2-(4-hydroxyphenyl)propane, 3,3-bis(3-methyl-4-hydroxyphenyl)-1-(4-hydroxyphenyl)butane, 1,3-bis(3-methyl-4-hydroxyphenyl)-3-(4-hydroxyphenyl)butane, 4,4-bis(3-methyl-4-hydroxyphenyl)-1-(4-hydroxyphenyl)pentane, 1,4-bis(3-methyl-4-hydroxyphenyl)-4-(4-hydroxyphenyl)pentane, 1,1,2-tris(3-methyl-4-hydroxyphenyl)ethane, 1,2,2-tris(3-methyl-4-hydroxyphenyl)propane, 1,1,3-tris(3-methyl-4-hydroxyphenyl)propane, 1,3,3-tris(3-methyl-4-hydroxyphenyl)butane, 1,1,4-tris(3-methyl-4-hydroxyphenyl)butane, 1,4,4-tris(3-methyl-4-hydroxyphenyl)pentane, 4,4'-[4-(4-hydroxyphenyl)-sec-butylidene]bis(2-methylphenol) Examples include:

[0020] Examples of compounds having four or more phenolic hydroxyl groups include: Bis[2-hydroxy-3-(2-hydroxy-5-methylbenzyl)-5-methylphenyl]methane, 4,6-bis[(4-hydroxyphenyl)methyl]-1,3-benzenediol, 4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2,6-dimethylphenol), 4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2-cyclohexyl-5-methylphenol), 4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2-methylphenol), 4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2,3,6-trimethylphenol), 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane, 1,1,2,2-tetrakis(4-hydroxy-3-methylphenyl)ethane, 1,1,2,2-tetrakis(3,5-dimethyl-4-hydroxyphenyl)ethane, α,α′,4α″,α′″-tetrakis(3,5-dimethyl-4-hydroxyphenyl)-1,4-dimethylbenzene, 2,2'-bis[4,4-bis(4-hydroxy-3-methylphenyl)cyclohexyl]propane, 2,2'-[(3,4-dihydroxyphenyl)methylene]bis(3,5-dimethylphenol), 3,6-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl]catechol, 4,6-bis[(3,5-dimethyl-4-hydroxyphenyl)methyl]-1,3-benzenediol, 2,2'-[(3,4-dihydroxyphenyl)methylene]bis(3,5,6-trimethylphenol), 4,4'-[(3,4-dihydroxyphenyl)methylene]bis(2-cyclohexylphenol), Bis[3-(2-hydroxybenzyl)-4-hydroxy-5-methylphenyl]methane, Bis[3-(3-hydroxybenzyl)-4-hydroxy-5-methylphenyl]methane, Bis[3-(4-hydroxybenzyl)-4-hydroxy-5-methylphenyl]methane, Bis[3-(2-hydroxybenzyl)-2-hydroxy-5-methylphenyl]methane, Bis[3-(2-hydroxybenzyl)-3-hydroxy-5-methylphenyl]methane, Bis[3-(2-hydroxybenzyl)-4-hydroxy-5-methylphenyl]methane, Bis[3-(3-hydroxy-2-methylbenzyl)-2-hydroxy-5-methylphenyl]methane, Bis[3-(4-hydroxy-3-methylbenzyl)-2-hydroxy-5-methylphenyl]methane, Bis[3-(3-hydroxy-4-methylbenzyl)-2-hydroxy-5-methylphenyl]methane, Bis[3-(2-hydroxy-3-methylbenzyl)-2-hydroxy-5-methylphenyl]methane, α,α′,α″,α′″-tetrakis(4-hydroxyphenyl)-1,4-dimethylbenzene, Bis[3-(3,6-dimethyl-2-hydroxybenzyl)-2-hydroxy-5-methylphenyl]methane, [3-(3,6-dimethyl-2-hydroxybenzyl)-2-hydroxy-5-methylphenyl], [3-(2,5-dimethyl-4-hydroxybenzyl)-2-hydroxy-5-methylphenyl]methane, Bis[3-(2,5-dimethyl-4-hydroxybenzyl)-2-hydroxy-5-methylphenyl]methane, Bis[3-(3,5-dimethyl-4-hydroxybenzyl)-2-hydroxy-5-methylphenyl]methane, Bis[3-(2-hydroxy-3,4,6-trimethylbenzyl)-2-hydroxy-5-methylphenyl]methane, Bis[2-hydroxy-3-(4-hydroxy-2,3,5-trimethylbenzyl)-5-methylphenyl]methane, 4,4′,4″,4′″-tetrakis(4-hydroxyphenyl)-1,1′-bicyclohexyl, 2,2'-bis[4,4-bis(4-hydroxyphenyl)cyclohexyl]propane, 4,4′,4″,4′″-tetrakis(4-hydroxy-3-methylphenyl)-1,1′-bicyclohexyl, Bis[3-(5-cyclohexyl-4-hydroxy-2-methylbenzyl)-4-hydroxy-5-methylphenyl]methane, 4,4′,4″,4′″-tetrakis(3,5-dimethyl-4-hydroxyphenyl)-1,1′-bicyclohexyl, 1,1-bis[3-(2-hydroxy-5-methylbenzyl)-5-cyclohexyl-4-hydroxyphenyl]cyclohexane, 1,1-bis[3-(3,5-dimethyl-4-hydroxybenzyl)-5-cyclohexyl-4-hydroxyphenyl]cyclohexane, 1,1-bis[3-(5-cyclohexyl-4-hydroxy-2-methylbenzyl)-5-cyclohexyl-4-hydroxyphenyl]cyclohexane, 4,6-bis[α-methyl-(4-hydroxyphenyl)benzyl-1,3-benzenediol, 2,2-bis[3-(4-hydroxy-3-methylbenzyl)-4-hydroxy-5-methylphenyl]propane, 2,6-bis[(3,5-dimethyl-4-hydroxyphenyl)benzyl]-4-[α-methyl-(3,5-dimethyl-4-hydroxyphenyl)benzyl]phenol, 4,4′,4″,4′″-tetrakis(4-hydroxy-3-isopropylphenyl)-1,1′-bicyclohexyl, 4,4'-bis[(3,4-dihydroxyphenyl)methylene]bis(2-isopropylphenol), 2,4,6-tris(4-hydroxybenzyl)-1,3-benzenediol, 4,6-bis(3,5-dimethyl-4-hydroxybenzyl)pyrogallol, 3,3'-[(2-hydroxyphenyl)methylene]bis(5-methylcatechol), 2,6-bis(2,4-dihydroxybenzyl)-4-ethylphenol, 2,4-bis(2,4-dihydroxybenzyl)-6-cyclohexylphenol, 2,6-bis(5-tert-butyl-2,3-dihydroxybenzyl)-4-methylphenol, 2,4,6-tris(3,5-dimethyl-4-hydroxybenzyl)resorcinol, 2,4,6-tris(3,5-dimethyl-2-hydroxybenzyl)resorcinol, 2,6-bis(2,4-dihydroxybenzyl)-3,4-dimethylphenol, 2,6-bis[3-(2-hydroxy-5-methylbenzyl)-2,5-dimethyl-4-hydroxybenzyl]-3,4-dimethylphenol, 4,6-bis(α-methyl-4-hydroxybenzyl)pyrogallol, 4,4'-[1-{4-[1-(3,5-bis(4-hydroxybenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxybenzyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-3-methylbenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-3-methylbenzyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(3,5-dimethyl-4-hydroxybenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(3,5-dimethyl-4-hydroxybenzyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-2,3,6-trimethylbenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-2,3,6-trimethylbenzyl)phenol], Bis[5-(2,4-dihydroxybenzyl)-4-hydroxy-3-methylphenyl]methane, bis[3-(2,4-dihydroxybenzyl)-2,5-dimethyl-4-hydroxyphenyl]methane, Bis[3-(2,4-dihydroxy-3-methylbenzyl)-2,5-dimethyl-4-hydroxyphenyl]methane, Bis[5-(4-hydroxybenzyl)-2,3,4-trihydroxyphenyl]methane, 1,1-bis[5-(4-hydroxybenzoyl)-2,3,4-trihydroxyphenyl]ethane, 3,3′,5,5′-tetrakis(4-hydroxybenzyl)-4,4′-dihydroxybiphenyl, 3,3′,5,5′-tetrakis(4-hydroxy-3-methylbenzyl)-4,4′-dihydroxybiphenyl, 3,3′,5,5′-tetrakis(2-hydroxy-5-methylbenzyl)-4,4′-dihydroxybiphenyl, 3,3′,5,5′-tetrakis(3,5-dimethyl-4-hydroxybenzyl)-4,4′-dihydroxybiphenyl, Bis[3-(α,α-bis(4-hydroxy-3-methylphenyl)methyl-4-hydroxyphenyl]methane, Bis[3,5-bis(2-hydroxy-5-methylbenzyl)-4-hydroxyphenyl]methane, 4,4',4"-ethylidinetris{[2-(2-hydroxy-5-methyl)benzyl]-6-methylphenol}, 2,2-bis[3,5-bis(2-hydroxy-5-methylphenylmethyl)phenyl]propane, Bis[3-(α,α-bis(2,5-dimethyl-4-hydroxyphenyl)methyl-4-hydroxyphenyl]methane, Bis[5-(3,5-dimethyl-4-hydroxybenzyl)-2,3,4-trihydroxyphenyl]methane, Bis[3-(2,3,4-trihydroxybenzyl)-2,5-dimethyl-4-hydroxyphenyl]methane, 1,1-bis[3-(2,3,4-trihydroxybenzyl)-5-cyclohexyl-4-hydroxyphenyl]cyclohexane, 1,8,15,22-tetranonyl-3,5,10,12,17,19,24,26-octahydroxy[1,1,1,1]-metacyclophane, 4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-2-methylbenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-2-methylbenzyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(2-hydroxy-5-methylbenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(2-hydroxy-5-methylbenzyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(3-ethyl-4-hydroxybenzyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(3-ethyl-4-hydroxybenzyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(3,5-dimethyl-2-hydroxyphenyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(3,5-dimethyl-2-hydroxyphenyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-3-isopropylphenyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-3-isopropylphenyl)phenol], Bis[3-(α,α-bis(3,5-dimethyl-4-hydroxyphenyl)methyl-4-hydroxyphenyl]methane, Bis[3-(α,α-bis(5-cyclohexyl-4-hydroxy-2-methylphenyl)methyl-4-hydroxyphenyl]methane, 4,4'-[4-hydroxy-3,5-bis(2-hydroxybenzyl)methylene]bis[2,6-bis(2-hydroxybenzyl)]phenol, 4,4'-[4-hydroxy-3,5-bis(4-hydroxybenzyl)methylene]bis[2,6-bis(4-hydroxybenzyl)]phenol, 4,4',4"-Ethylidinetris[2,6-bis(2-hydroxybenzyl)phenol], 4,4',4"-Ethylidinetris[2,6-bis(4-hydroxybenzyl)phenol], 2,2-bis[3,5-bis(4-hydroxy-3-methylbenzyl)-4-hydroxyphenyl]propane, 1,8,15,22-tetraethyl-3,5,10,12,17,19,24,26-octahydroxy[1,1,1,1]-metacyclophane, α,α′,α″,α′″-tetrakis(3,5-dimethyl-4-hydroxyphenyl)-1,4-dimethylbenzene, 4,4'-[1-{4-[1-(3,5-bis(2-hydroxy-5-isopropylphenyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(2-hydroxy-5-isopropylphenyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(4-hydroxy-2,3,5-trimethylphenyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(4-hydroxy-2,3,5-trimethylphenyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(3-sec-butyl-4-hydroxyphenyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(3-sec-butyl-4-hydroxyphenyl)phenol], 4,4'-[1-{4-[1-(3,5-bis(3-tert-butyl-4-hydroxyphenyl)-4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bis[2,6-bis(3-tert-butyl-4-hydroxyphenyl)phenol], 2,6-bis{[3-(2,4-dihydroxybenzyl)-2,5-dimethyl-4-hydroxy]benzyl}-4-methylphenol, 1,1-bis[5-(2,4-dihydroxybenzyl)-3-cyclohexyl-4-hydroxyphenyl]cyclohexane, 1,1-bis[5-(2,3,4-trihydroxybenzyl)-3-cyclohexyl-4-hydroxyphenyl]cyclohexane, 2,2-bis[4,4',4'',4'''-tetrakis(3,5-dihydroxymethyl-4-hydroxyphenyl)cyclohexyl]propane Examples include:

[0021] Examples of carboxylic acids and derivatives thereof include: 3,5-di(α-methylbenzyl)salicylic acid, 4-(2-p-methoxyphenyloxyethoxy)salicylic acid, 4-hydroxyphenylbenzoic acid, 4-chlorobenzoic acid, 4-[2-(p-methoxyphenoxy)ethyloxy]salicylic acid, 4-[3-(p-tolylsulfonyl)propyloxy]salicylic acid, 5-[p-(2-p-methoxyphenoxyethoxy)cumyl]salicylic acid, 4-octyloxycarbonylaminosalicylic acid, 3,5-distyrenated salicylic acid, N-(p-toluenesulfonyl)-glycine, N-(p-toluenesulfonyl)-alanine, N-(p-toluenesulfonyl)-β-alanine, N-phenylaminocarbonyl-glycine, N-phenylaminocarbonyl-valine, N-(m-tolylaminocarbonyl)-phenylalanine, N-(m-tolylaminocarbonyl)-cysteine-S-benzyl, N-(m-tolylaminocarbonyl)-methionine, N-(m-tolylaminocarbonyl)-tyrosine, N-(p-tolylaminocarbonyl)-phenylalanine, N-(p-tolylaminocarbonyl)-cysteine-S-benzyl, N-(p-tolylaminocarbonyl)-methionine, N-(p-tolylaminocarbonyl)-methionine, N-(phenylaminocarbonyl)-methionine, N-(p-tolylaminocarbonyl)-tyrosine, 2-O-(phenylaminocarbonyl)-mandelic acid, 2-O-(p-tolylaminocarbonyl)-mandelic acid, 2-O-(m-tolylaminocarbonyl)-mandelic acid, 2-O-(o-tolylaminocarbonyl)-mandelic acid, 2-O-(1-naphthylaminocarbonyl)-mandelic acid, 2-O-(3-isopropenyl-α,α-dimethylbenzylaminocarbonyl)-mandelic acid, 2-O-(benzylaminocarbonyl)-mandelic acid, 2-O-(phenethylaminocarbonyl)-mandelic acid, 2-O-(phenylaminocarbonyl)-lactic acid, 2-O-(p-tolylaminocarbonyl)-lactic acid, 2-O-(m-tolylaminocarbonyl)-lactic acid, 2-O-(o-tolylaminocarbonyl)-lactic acid, 2-O-(1-naphthylaminocarbonyl)-lactic acid, 2-O-(3-isopropenyl-α,α-dimethylbenzylaminocarbonyl)-lactic acid, 2-O-(benzylaminocarbonyl)-lactic acid, 2-O-(phenethylaminocarbonyl)-lactic acid Examples include:

[0022] Examples of acidic phosphate ester compounds include methyl acid phosphate, ethyl acid phosphate, butyl acid phosphate, butoxyethyl acid phosphate, 2-ethylhexyl acid phosphate, isodecyl acid phosphate, isotridecyl acid phosphate, oleyl acid phosphate, tetracosyl acid phosphate, monobutyl phosphate, dibutyl phosphate, monoisodecyl phosphate, and bis(2-ethylhexyl) phosphate.

[0023] The component (c) of the reaction medium that reversibly induces an electron transfer reaction between the components (a) and (b) in a specific temperature range will now 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 encapsulated in microcapsules and used for secondary processing, compounds with a carbon number of 10 or more are preferably used to stably retain the composition in the capsules, since low molecular weight compounds will evaporate out of the capsules when subjected to high heat treatment.

[0024] As the alcohols, aliphatic monohydric saturated alcohols having 10 or more carbon atoms are effective, and examples thereof include decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, tetradecyl alcohol, pentadecyl alcohol, hexadecyl alcohol, heptadecyl alcohol, octadecyl alcohol, eicosyl alcohol, and docosyl alcohol.

[0025] As the esters, esters having 10 or more carbon atoms are effective, and examples thereof include esters obtained from any combination of a monocarboxylic acid having an aliphatic and alicyclic or aromatic ring and a monohydric alcohol having an aliphatic and alicyclic or aromatic ring, esters obtained from any combination of a polycarboxylic acid having an aliphatic and alicyclic or aromatic ring and a monohydric alcohol having an aliphatic and alicyclic or aromatic ring, and esters obtained from any combination of a monocarboxylic acid having an aliphatic and alicyclic or aromatic ring and a polyhydric alcohol having an aliphatic and alicyclic or aromatic ring. Examples of esters include esters obtained by combining ethyl caprylate, octyl caprylate, stearyl caprylate, myristyl caprate, docosyl caprate, 2-ethylhexyl laurate, n-decyl laurate, 3-methylbutyl myristate, cetyl myristate, isopropyl palmitate, neopentyl palmitate, nonyl palmitate, cyclohexyl palmitate, n-butyl stearate, 2-methylbutyl stearate, 3,5,5-trimethylhexyl stearate, stearyl stea ... n-Undecyl Phosphate, Pentadecyl Stearate, Stearyl Stearate, Cyclohexylmethyl Stearate, Isopropyl Behenate, Hexyl Behenate, Lauryl Behenate, Behenyl Behenate, Cetyl Benzoate, Stearyl 4-tert-Butylbenzoate, Dimyristyl Phthalate, Distearyl Phthalate, Dimyristyl Oxalate, Dicetyl Oxalate, Dicetyl Malonate, Dilauryl Succinate, Dilauryl Glutarate, Diundecyl Adipate, Dilauryl Azelaate, Di-(n-Nonyl) Sebacate, Examples include dineopentyl 1,18-octadecylmethylenedicarboxylate, ethylene glycol dimyristate, propylene glycol dilaurate, propylene glycol distearate, hexylene glycol dipalmitate, 1,5-pentanediol distearate, 1,2,6-hexanetriol trimyristate, 1,4-cyclohexanediol didecyl, 1,4-cyclohexanedimethanol dimyristate, xylene glycol dicaprinate, and xylene glycol distearate.

[0026] Also effective are esters of saturated fatty acids and branched fatty alcohols, and ester compounds of unsaturated fatty acids or branched or substituted saturated fatty acids and branched or aliphatic alcohols having 16 or more carbon atoms. Examples of the ester compounds include 2-ethylhexyl butyrate, 2-ethylhexyl behenate, 2-ethylhexyl myristate, 2-ethylhexyl caprate, 3,5,5-trimethylhexyl laurate, 3,5,5-trimethylhexyl palmitate, 3,5,5-trimethylhexyl stearate, 2-methylbutyl caproate, 2-methylbutyl caprylate, 2-methylbutyl caprate, 1-ethylpropyl palmitate, 1-ethylpropyl stearate, 1-ethylpropyl behenate, laurate, 3,5,5-trimethylhexyl laurate, 3,5,5-trimethylhexyl palmitate, 3,5,5-trimethylhexyl stearate, 3,5,5-trimethylhexyl laurate, 3,5,5-trimethylhexyl stearate, 2-methylbutyl caproate, 2-methylbutyl caprylate, 2-methylbutyl caprate, 1-ethylpropyl palmitate, 1-ethylpropyl stearate, 1-ethylpropyl behenate, laurate, 3,5,5-trimethylhexyl laurate, 3,5,5-trimethylhexyl laurate, 3,5,5-trimethylhexyl stea ...stearate, 3,5,5-trimethylhexyl stearate, 3,5,5-trimethylhexyl stearate, 3,5,5-trimethylhexyl stearate, 3,5,5-trimethylhexyl stearate, 3,5,5- 1-Ethylhexyl phosphate, 1-ethylhexyl myristate, 1-ethylhexyl palmitate, 2-methylpentyl caproate, 2-methylpentyl caprylate, 2-methylpentyl caprate, 2-methylpentyl laurate, 2-methylbutyl stearate, 2-methylbutyl stearate, 3-methylbutyl stearate, 1-methylheptyl stearate, 2-methylbutyl behenate, 3-methylbutyl behenate, 1-methylheptyl stearate, 1-methylheptyl behenate, 1-ethyl caproate pentyl palmitate, 1-ethylpentyl palmitate, 1-methylpropyl stearate, 1-methyloctyl stearate, 1-methylhexyl stearate, 1,1-dimethylpropyl laurate, 1-methylpentyl caprate, 2-methylhexyl palmitate, 2-methylhexyl stearate, 2-methylhexyl behenate, 3,7-dimethyloctyl laurate, 3,7-dimethyloctyl myristate, 3,7-dimethyloctyl palmitate, 3,7-dimethyloctyl stearate, 3,7 behenate Examples include 3,7-dimethyloctyl erucate, stearyl oleate, behenyl oleate, stearyl linoleate, behenyl linoleate, 3,7-dimethyloctyl erucate, stearyl erucate, isostearyl erucate, cetyl isostearate, stearyl isostearate, 2-methylpentyl 12-hydroxystearate, 2-ethylhexyl 18-bromostearate, isostearyl 2-ketomyristate, 2-ethylhexyl 2-fluoromyristate, cetyl butyrate, stearyl butyrate, and behenyl butyrate.

[0027] Furthermore, in order to cause a color change that exhibits large hysteresis characteristics in the color density-temperature curve and to impart color memory properties that depend on temperature changes, exemplified are carboxylic acid ester compounds that exhibit a ΔT value (melting point-cloud point) of 5°C or more and less than 50°C, as described in Japanese Patent Publication No. 4-17154, such as carboxylic acid esters containing a substituted aromatic ring in the molecule, esters of carboxylic acids containing an unsubstituted aromatic ring and aliphatic alcohols having 10 or more carbon atoms, carboxylic acid esters containing a cyclohexyl group in the molecule, esters of fatty acids having 6 or more carbon atoms and unsubstituted aromatic alcohols or phenols, esters of fatty acids having 8 or more carbon atoms and branched aliphatic alcohols, esters of dicarboxylic acids and aromatic alcohols or branched aliphatic alcohols, dibenzyl cinnamate, heptyl stearate, didecyl adipate, dilauryl adipate, dimyristyl adipate, dicetyl adipate, distearyl adipate, trilaurin, trimyristin, tristearin, dimyristin, distearin, and the like.

[0028] Also effective are fatty acid ester compounds obtained from an odd-numbered aliphatic monohydric alcohol having 9 or more carbon atoms and an even-numbered aliphatic carboxylic acid, and fatty acid ester compounds having a total of 17 to 23 carbon atoms obtained from n-pentyl alcohol or n-heptyl alcohol and an even-numbered aliphatic carboxylic acid having 10 to 16 carbon atoms. Examples of the fatty acid ester compound include n-pentadecyl acetate, n-tridecyl butyrate, n-pentadecyl butyrate, n-undecyl caproate, n-tridecyl caproate, n-pentadecyl caproate, n-nonyl caprylate, n-undecyl caprylate, n-tridecyl caprylate, n-pentadecyl caprylate, n-heptyl caprate, n-nonyl caprate, n-undecyl caprate, n-tridecyl caprate, n-pentadecyl caprate, n-pentyl laurate, n-heptyl laurate, n-nonyl laurate, n-undecyl laurate, n-tridecyl laurate, n-pentadecyl laurate, n-pentyl myristate, and n-heptyl myristate. Examples include n-pentyl palmitate, n-heptyl palmitate, n-nonyl palmitate, n-undecyl palmitate, n-tridecyl myristate, n-pentadecyl myristate, n-pentyl palmitate, n-heptyl palmitate, n-nonyl palmitate, n-undecyl palmitate, n-tridecyl palmitate, n-pentadecyl palmitate, n-nonyl stearate, n-undecyl stearate, n-tridecyl stearate, n-pentadecyl stearate, n-nonyl eicosanoate, n-undelcyl eicosanoate, n-tridecyl eicosanoate, n-pentadecyl eicosanoate, n-nonyl behenate, n-undecyl behenate, n-tridecyl behenate, and n-pentadecyl behenate.

[0029] As the ketones, aliphatic ketones having a total carbon number of 10 or more are effective, and examples thereof include 2-decanone, 3-decanone, 4-decanone, 2-undecanone, 3-undecanone, 4-undecanone, 5-undecanone, 2-dodecanone, 3-dodecanone, 4-dodecanone, 5-dodecanone, 2-tridecanone, 3-tridecanone, 2-tetradecanone, 2-pentadecanone, 8-pentadecanone, 2-hexadecanone, 3-hexadecanone, 9-heptadecanone, 2-pentadecanone, 2-octadecanone, 2-nonadecanone, 10-nonadecanone, 2-eicosanone, 11-eicosanone, 2-heneicosanone, 2-docosanone, laurone, stearone, and the like. Further, aryl alkyl ketones having a total carbon number of 12 to 24, for example, n-octadecanophenone, n-heptadecanophenone, n-hexadecanophenone, n-pentadecanophenone, n-tetradecanophenone, 4-n-dodecaacetophenone, n-tridecanophenone, 4-n-undecanoacetophenone, n-laurophenone, 4-n-decanoacetophenone, n-undecanophenone, 4-n-nonylacetophenone, n-decanophenone, 4-n-octylacetophenone, n ... Examples of acetophenone include 4-n-heptylacetophenone, n-octanophenone, 4-n-hexylacetophenone, 4-n-cyclohexylacetophenone, 4-tert-butylpropiophenone, n-heptaphenone, 4-n-pentylacetophenone, cyclohexyl phenyl ketone, benzyl-n-butyl ketone, 4-n-butylacetophenone, n-hexanophenone, 4-isobutylacetophenone, 1-acetonaphthone, 2-acetonaphthone, and cyclopentyl phenyl ketone.

[0030] As the ethers, aliphatic ethers having a total of 10 or more carbon atoms are effective, and examples thereof include dipentyl ether, dihexyl ether, diheptyl ether, dioctyl ether, dinonyl ether, didecyl ether, diundecyl ether, didodecyl ether, ditridecyl ether, ditetradecyl ether, dipentadecyl ether, dihexadecyl ether, dioctadecyl ether, decanediol dimethyl ether, undecanediol dimethyl ether, dodecanediol dimethyl ether, tridecanediol dimethyl ether, decanediol diethyl ether, and undecanediol diethyl ether.

[0031] Examples of acid amides include acetamide, propionic acid amide, butyric acid amide, caproic acid amide, caprylic acid amide, capric acid amide, lauric acid amide, myristic acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, oleic acid amide, erucic acid amide, benzamide, caproic acid anilide, caprylic acid anilide, capric acid anilide, lauric acid anilide, myristic acid anilide, palmitic acid anilide, stearic acid anilide, behenic acid anilide, oleic acid anilide, erucic acid anilide, and N-methyl caproate. amide, caprylic acid N-methylamide, capric acid N-methylamide, lauric acid N-methylamide, myristic acid N-methylamide, palmitic acid N-methylamide, stearic acid N-methylamide, behenic acid N-methylamide, oleic acid N-methylamide, erucic acid N-methylamide, lauric acid N-ethylamide, myristic acid N-ethylamide, palmitic acid N-ethylamide, stearic acid N-ethylamide, oleic acid N-ethylamide, lauric acid N-butylamide, myristic acid N-butylamide, palmitic acid N-butylamide, stearate Stearic acid N-butylamide, oleic acid N-butylamide, lauric acid N-octylamide, myristic acid N-octylamide, palmitic acid N-octylamide, stearic acid N-octylamide, oleic acid N-octylamide, lauric acid N-dodecylamide, myristic acid N-dodecylamide, palmitic acid N-dodecylamide, stearic acid N-dodecylamide, oleic acid N-dodecylamide, dilauric acid amide, dimyristic acid amide, dipalmitic acid amide, distearic acid amide, dioleic acid amide, trilauric acid amide, trilauric acid amide Rimyristic acid amide, tripalmitic acid amide, tristearic acid amide, trioleic acid amide, succinic acid amide, adipic acid amide, glutaric acid amide, malonic acid amide, azelaic acid amide, maleic acid amide, succinic acid N-methylamide, adipic acid N-methylamide, glutaric acid N-methylamide, malonic acid N-methylamide, azelaic acid N-methylamide, succinic acid N-ethylamide, adipic acid N-ethylamide, glutaric acid N-ethylamide, malonic acid N-ethylamide, azelaic acid N-ethylamide, succinic acid N-butylamide,Examples include adipic acid N-butylamide, glutaric acid N-butylamide, malonic acid N-butylamide, adipic acid N-octylamide, and adipic acid N-dodecylamide.

[0032] Furthermore, the component (iii) may be a compound represented by the following formula (3). [ka] [wherein R1 represents a hydrogen atom or a methyl group, m represents an integer of 0 to 2, and either X1 or X2 represents -(CH2) n OCOR2 or -(CH2) n COOR2, and the other represents a hydrogen atom; n represents an integer of 0 to 2; R2 represents an alkyl or alkenyl group having 4 or more carbon atoms; Y1 and Y2 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a methoxy group, or a halogen atom; and r and p each independently represent an integer of 1 to 3. Of the compounds represented by formula (3), it is preferable that R1 is a hydrogen atom, since this results in a reversible thermochromic composition with a wider hysteresis width, and it is even more preferable that R1 is a hydrogen atom and m is 0. Among the compounds represented by formula (3), the compound represented by the following formula (4) is more preferred. [ka] (In the formula, R represents an alkyl group or 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.) Examples of the compound represented by formula (4) include 4-benzyloxyphenylethyl octanoate, 4-benzyloxyphenylethyl nonanoate, 4-benzyloxyphenylethyl decanoate, 4-benzyloxyphenylethyl undecanoate, 4-benzyloxyphenylethyl dodecanoate, 4-benzyloxyphenylethyl tridecanoate, 4-benzyloxyphenylethyl tetradecanoate, 4-benzyloxyphenylethyl pentadecanoate, 4-benzyloxyphenylethyl hexadecanoate, 4-benzyloxyphenylethyl heptadecanoate, and 4-benzyloxyphenylethyl octadecanoate.

[0033] Furthermore, the component (iii) may be a compound represented by the following formula (5). [ka] (In the formula, R represents an alkyl or alkenyl 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, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom.) Examples of the compound represented by formula (5) include 1,1-diphenylmethyl octanoate, 1,1-diphenylmethyl nonanoate, 1,1-diphenylmethyl decanoate, 1,1-diphenylmethyl undecanoate, 1,1-diphenylmethyl dodecanoate, 1,1-diphenylmethyl tridecanoate, 1,1-diphenylmethyl tetradecanoate, 1,1-diphenylmethyl pentadecanoate, 1,1-diphenylmethyl hexadecanoate, 1,1-diphenylmethyl heptadecanoate, and 1,1-diphenylmethyl octadecanoate.

[0034] Furthermore, the component (iii) may be a compound represented by the following formula (6). [ka] (In the formula, X represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a methoxy group, or a halogen atom; m represents an integer of 1 to 3; and n represents an integer of 1 to 20.) Examples of the compound represented by formula (6) include a diester of malonic acid and 2-[4-(4-chlorobenzyloxy)phenyl]ethanol, a diester of succinic acid and 2-(4-benzyloxyphenyl)ethanol, a diester of succinic acid and 2-[4-(3-methylbenzyloxy)phenyl]ethanol, a diester of glutaric acid and 2-(4-benzyloxyphenyl)ethanol, a diester of glutaric acid and 2-[4-(4-chlorobenzyloxy)phenyl]ethanol, a diester of adipic acid and 2-(4-benzyloxyphenyl)ethanol, a diester of pimelic acid and 2-(4-benzyloxyphenyl)ethanol, a diester of suberic acid and 2-(4-benzyloxyphenyl)ethanol, a diester of suberic acid and 2-[4-(3-methylbenzyloxy)phenyl]ethanol, a diester of glutaric acid and 2-(4-benzyloxyphenyl)ethanol, a diester of adipic acid and 2-(4-benzyloxyphenyl)ethanol, a diester of pimelic acid and 2-(4-benzyloxyphenyl)ethanol, a diester of suberic acid and 2-[4-(3-methylbenzyloxy)phenyl]ethanol, a diester of adipic acid and 2-(4-benzyloxyphenyl) ... Examples include the diester of suberic acid and 2-[4-(4-chlorobenzyloxy)phenyl]ethanol, the diester of suberic acid and 2-[4-(2,4-dichlorobenzyloxy)phenyl]ethanol, the diester of suberic acid and 2-[4-(2,4-dichlorobenzyloxy)phenyl]ethanol, the diester of azelaic acid and 2-(4-benzyloxyphenyl)ethanol, the diester of sebacic acid and 2-(4-benzyloxyphenyl)ethanol, the diester of 1,10-decanedicarboxylic acid and 2-(4-benzyloxyphenyl)ethanol, the diester of 1,18-octadecanedicarboxylic acid and 2-(4-benzyloxyphenyl)ethanol, and the diester of 1,18-octadecanedicarboxylic acid and 2-[4-(2-methylbenzyloxy)phenyl]ethanol.

[0035] Furthermore, the component (iii) may be a compound represented by the following formula (7). [ka] (In the formula, R represents an alkyl group or alkenyl group having 1 to 21 carbon atoms, and n represents an integer of 1 to 3.) Examples of the compound represented by formula (7) include a diester of 1,3-bis(2-hydroxyethoxy)benzene and capric acid, a diester of 1,3-bis(2-hydroxyethoxy)benzene and undecanoic acid, a diester of 1,3-bis(2-hydroxyethoxy)benzene and lauric acid, a diester of 1,3-bis(2-hydroxyethoxy)benzene and myristic acid, a diester of 1,4-bis(hydroxymethoxy)benzene and butyric acid, a diester of 1,4-bis(hydroxymethoxy)benzene and isovaleric acid, and a diester of 1,4-bis(2-hydroxyethoxy)benzene and acetic acid. Examples of such esters include esters of 1,4-bis(2-hydroxyethoxy)benzene and propionic acid, diesters of 1,4-bis(2-hydroxyethoxy)benzene and valeric acid, diesters of 1,4-bis(2-hydroxyethoxy)benzene and caproic acid, diesters of 1,4-bis(2-hydroxyethoxy)benzene and caprylic acid, diesters of 1,4-bis(2-hydroxyethoxy)benzene and capric acid, diesters of 1,4-bis(2-hydroxyethoxy)benzene and lauric acid, and diesters of 1,4-bis(2-hydroxyethoxy)benzene and myristic acid.

[0036] Furthermore, the component (iii) may be a compound represented by the following formula (8). [ka] (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 an integer of 1 to 20.) Examples of the compound represented by formula (8) include a diester of succinic acid and 2-phenoxyethanol, a diester of suberic acid and 2-phenoxyethanol, a diester of sebacic acid and 2-phenoxyethanol, a diester of 1,10-decanedicarboxylic acid and 2-phenoxyethanol, and a diester of 1,18-octadecanedicarboxylic acid and 2-phenoxyethanol.

[0037] Furthermore, the component (iii) may be a compound represented by the following formula (9). [ka] (In the formula, R represents an alkyl group having 4 to 22 carbon atoms, a cycloalkylalkyl group, a cycloalkyl group, or an alkenyl group having 4 to 22 carbon atoms; 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; and n represents 0 or 1.) Examples of the compound represented by formula (9) include decyl 4-phenylbenzoate, lauryl 4-phenylbenzoate, myristyl 4-phenylbenzoate, cyclohexylethyl 4-phenylbenzoate, octyl 4-biphenylacetate, nonyl 4-biphenylacetate, decyl 4-biphenylacetate, lauryl 4-biphenylacetate, myristyl 4-biphenylacetate, tridecyl 4-biphenylacetate, pentadecyl 4-biphenylacetate, cetyl 4-biphenylacetate, cyclopentyl 4-biphenylacetate, cyclohexylmethyl 4-biphenylacetate, hexyl 4-biphenylacetate, and cyclohexylmethyl 4-biphenylacetate.

[0038] Furthermore, the component (iii) may be a compound represented by the following formula (10). [ka] (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; X represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 or 2 carbon atoms, or a halogen atom; Y represents a hydrogen atom or a methyl group; and Z represents 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.) Examples of the compound represented by formula (10) include phenoxyethyl 4-butoxybenzoate, phenoxyethyl 4-pentyloxybenzoate, phenoxyethyl 4-tetradecyloxybenzoate, esters of phenoxyethyl 4-hydroxybenzoate and dodecanoic acid, and dodecyl ether of phenoxyethyl vanillate.

[0039] Furthermore, the component (iii) may be a compound represented by the following formula (11). [ka] (In the formula, R represents any one 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; X represents any one of a hydrogen atom, an alkyl group, an alkoxy group, and a halogen atom; Y represents any one of a hydrogen atom, an alkyl group, an alkoxy group, and a halogen atom; and n represents 0 or 1.) Examples of the compound represented by formula (11) include the benzoate ester of octyl 4-hydroxybenzoate, the benzoate ester of decyl 4-hydroxybenzoate, the 4-methoxybenzoate ester of heptyl 4-hydroxybenzoate, the 2-methoxybenzoate ester of dodecyl 4-hydroxybenzoate, and the benzoate ester of cyclohexylmethyl 4-hydroxybenzoate.

[0040] Furthermore, the component (iii) may be a compound represented by the following formula (12). [ka] (In the formula, R represents any one 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 alkenyl group having 3 to 18 carbon atoms; X represents any one 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 represents any one of a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, a methoxy group, an ethoxy group, and a halogen atom.) Examples of the compound represented by formula (12) include phenoxyethyl ether of nonyl 4-hydroxybenzoate, phenoxyethyl ether of decyl 4-hydroxybenzoate, phenoxyethyl ether of undecyl 4-hydroxybenzoate, and phenoxyethyl ether of dodecyl vanillate.

[0041] Furthermore, the component (iii) may be a compound represented by the following formula (13). [ka] (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.) Examples of the compound represented by formula (13) include a diester of 1,3-bis(2-hydroxyethoxy)benzene and cyclohexanecarboxylic acid, a diester of 1,4-bis(2-hydroxyethoxy)benzene and cyclohexanepropionic acid, and a diester of 1,3-bis(2-hydroxyethoxy)benzene and cyclohexanepropionic acid.

[0042] Furthermore, the component (iii) may be a compound represented by the following formula (14). [ka] (In the formula, R represents any one 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; X represents any one of a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a methoxy group, an ethoxy group, and a halogen atom; and n represents an integer of 1 to 3.) Examples of the compound represented by formula (14) include a diester of 4-phenylphenol ethylene glycol ether and cyclohexanecarboxylic acid, a diester of 4-phenylphenol diethylene glycol ether and lauric acid, a diester of 4-phenylphenol triethylene glycol ether and cyclohexanecarboxylic acid, a diester of 4-phenylphenol ethylene glycol ether and octanoic acid, a diester of 4-phenylphenol ethylene glycol ether and nonanoic acid, a diester of 4-phenylphenol ethylene glycol ether and decanoic acid, and a diester of 4-phenylphenol ethylene glycol ether and myristic acid.

[0043] The reversible thermochromic composition of the present invention essentially comprises the components (A), (B), and (C), and the proportions of each component depend on the concentration, discoloration temperature, discoloration form, and type of each component. Generally, the component ratios that provide the desired properties are 1 part of component (A) to 0.1 to 100, preferably 0.1 to 50, and more preferably 0.5 to 20, of component (B), and 5 to 200, preferably 5 to 100, and more preferably 10 to 100, of component (C) (all of the above proportions are in parts by mass).

[0044] Furthermore, the reversible thermochromic composition may contain various light stabilizers as required. The light stabilizer is contained to prevent photodegradation of the reversible thermochromic composition consisting of components (A), (B), and (C), and is blended in a proportion of 0.3 to 24 mass%, preferably 0.3 to 16 mass%, per 1 mass% of component (A). Among the light stabilizers, ultraviolet absorbers effectively block ultraviolet rays contained in sunlight and the like, preventing photodegradation caused by the excited state due to the photoreaction of component (A). Furthermore, antioxidants, singlet oxygen quenchers, superoxide anion quenchers, ozone quenchers, etc. suppress photooxidation reactions. The light stabilizers may be used alone or in combination of two or more.

[0045] Among light stabilizers, examples of ultraviolet absorbers include: 2,4-hydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2′,4,4′-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonic acid, 2-hydroxy-4-octyloxybenzophenone, bis-(5-benzoyl-4-hydroxy-2-methoxyphenyl)-methane, 2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzophenone, 4-dodecyloxy-2-hydroxybenzophenone, 2-hydroxy-4-octadecyloxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, 4-benzyloxy-2-hydroxybenzophenone, 2-(3',5'-di-tert-amyl-2'-hydroxyphenyl)benzophenone Benzophenone-based ultraviolet absorbers such as Phenyl salicylate, 4-tert-butylphenyl salicylate, 4-octylphenyl salicylate, 2,4-di-tert-butylphenyl-4-hydroxybenzoate, 1-hydroxybenzoate, 3-tert-butyl-1-hydroxybenzoate, 1-hydroxy-3-tert-octyl benzoate, Resorcinol Monobenzoate salicylic acid-based ultraviolet absorbers such as 2-ethyl-2-cyano-3,3′-diphenylacrylate, 2-ethylhexyl-2-cyano-3,3′-diphenylacrylate, 2-Ethylhexyl-2-cyano-3-phenylcinnate Cyanoacrylate ultraviolet absorbers such as 2-(5-tert-butyl-2-hydroxyphenyl)benzotriazole, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-[3,5-bis(a,a-dimethylbenzyl)-2-hydroxyphenyl]-2H-benzotriazole, 2-(3,5-di-tert-butyl-2-hydroxyphenyl)benzotriazole, 2-(3-tert-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzotriazole, 2-(3,5-di-tert-butyl-2-hydroxyphenyl)-5-chlorobenzotriazole, 2-(3,5-di-tert-amyl-2-hydroxyphenyl)benzotriazole, β-[3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propionic acid-polyethylene glycol 300 ester, 2-(3-dodecyl-2-hydroxy-5-methylphenyl)benzotriazole, Bis{β-[3-(2H-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]}propionic acid-polyethylene glycol 300 ester, 2-(3-tert-butyl-2-hydroxyphenyl-5-propyloctylate)-5-chlorobenzotriazole, 2-[2-hydroxyphenyl-3,5-di-(1,1′-dimethylbenzyl)phenyl]-2H-benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)-2H-benzotriazole, 2-(3-tert-butyl-5-octyloxycarbonylethyl-2-hydroxyphenyl)benzotriazole, 2-(2-hydroxy-5-tetraoctylphenyl)benzotriazole, 2-(2-hydroxy-4-octoxyphenyl)benzotriazole, 2-[2'-hydroxy-3'-(3",4",5",6"-tetrahydrophthalimidomethyl)-5'-methylphenyl]benzotriazole, 2-(5-tert-butyl-2-hydroxyphenyl)benzotriazole Benzotriazole-based ultraviolet absorbers such as Ethanediamide-N-(2-ethoxyphenyl)-N′-(4-isododecylphenyl), 2,2,4,4-tetramethyl-20-(β-lauryloxycarbonyl)-ethyl-7-oxa-3,20-diazodispiro(5,1,11,2)heneicoic acid-21-one oxalic acid anilide-based ultraviolet absorbers such as 2,4-diphenyl-6-(2-hydroxy-4-methoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-ethoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-propoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-butoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-hexyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-pentoxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-dodecyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-(2-hydroxy-4-benzyloxyphenyl)-1,3,5-triazine, 2,4-diphenyl-6-[2-hydroxy-4-(2-butoxyethoxy)phenyl]-1,3,5-triazine, 2,4-di-p-trail-6-(2-hydroxy-4-methoxyphenyl)-1,3,5-triazine, 2,4-di-p-trail-6-(2-hydroxy-4-propoxyphenyl)-1,3,5-triazine, 2,4-di-p-trail-6-(2-hydroxy-4-butoxyphenyl)-1,3,5-triazine, 2,4-di-p-trail-6-(2-hydroxy-4-hexyloxyphenyl)-1,3,5-triazine, 2,4-di-p-trail-6-(2-hydroxy-4-pentoxyphenyl)-1,3,5-triazine, 2,4-di-p-trail-6-(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine, 2,4-di-p-trail-6-(2-hydroxy-4-benzyloxyphenyl)-1,3,5-triazine, 2,4-di-p-trail-6-[2-hydroxy-4-(2-hexyloxyethoxy)phenyl]-1,3,5-triazine, 2-{4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl}-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-{4-[(2-hydroxy-3-tridecyloxypropyl)oxy]-2-hydroxyphenyl}-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-[4-{[2-hydroxy-3-(2'-ethyl)hexyl]oxy}-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-[2,4-bis(butyloxyphenyl)]-1,3,5-triazine, 2-{2-hydroxy-4-[(1-octyloxycarbonylethoxy)phenyl]}-4,6-bis(4-phenylphenyl)-1,3,5-triazine Examples of such triazine-based ultraviolet absorbers include:

[0046] Examples of antioxidants (anti-aging agents) include: Dimethyl succinate-1-(2-hydroxyethyl)-4-hydroxy-2,2,6,6-tetramethylpiperidine polycondensate, poly{[6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine-2-4-diyl][(2,2,6,6-tetramethyl-4-piperidyl)imino]hexamethylene[(2,2,6,6-tetramethyl-4-piperidyl)imino]}hexamethylene, 2-(3,5-di-tert-butyl-4-hydroxybenzyl)-2-n-butylmalonate bis(1,2,2,6,6-pentapetyl-4-piperidyl), N,N'-bis(3-aminopropyl)ethylenediamine-2,4-bis[N-butyl-N-(1,2,2,6,6-pentapetyl-4-piperidyl)amino]-6-chloro-1,3,5-triazine condensate, Bis(1,2,2,6,6-pentamethyl-4-piperidylsebacic acid), 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, 8-Acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4,5]decane-2,4-dione hindered amine antioxidants such as 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl-4-methoxyphenol, 2,6-di-tert-butyl-4-ethylphenol, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,2-methylenebis(4-methyl-6-tert-butylphenol), 4,4-thiobis(2-methyl-6-tert-butylphenol), 2,2-thiobis(4-methyl-6-tert-butylphenol), 4,4-butylidenebis(3-methyl-6-tert-butylphenol), 3,9-bis{1,1-dimethyl-2-[β-(3-tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]ethyl}, 2,4,8,10-tetraoxaspiro[5,5]undecane, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane, 2,2-ethylenebis(4,6-di-tert-butylphenol), Bis[3,3-bis-(4'-hydroxy-3'-tert-butylphenyl)butyric acid]glycol ester, 1,3,5-tris(3′,5′-di-tert-butyl-4′-hydroxybenzyl)-S-triazine-2,4,6-[1H,3H,5H]-trione, Tocopherol, 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, Pentaerythritol tetrakis(3-laurylthiopropionate), triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexadiol-bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2,2-thioethylenebis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexamethylenebis(3,5-tert-butyl-4-hydroxy-hydrocinnamamide), tris-(3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 2,2,4-trimethyl-1,2-hydroquinone, Styryl phenol, 2,5-di-tert-butylhydroquinone, Bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate phenolic antioxidants such as Dilauryl-3,3′-thiodipropionate, Dimyristyl-3,3′-thiodipropionate, Distearyl-3,3′-thiodipropionate, Stearylthiopropylamide sulfur-based antioxidants such as tris(2,4-di-tert-butylphenyl)phosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, 3,5-di-tert-butyl-4-hydroxy-benzylphosphanate-diethyl ester, triphenyl phosphite, diphenyl isodecyl phosphite, phenyl isodecyl phosphite, 4,4′-butylidene-bis(3-methyl-6-tert-butylphenylditridecyl)phosphite, octadecyl phosphite, Tris(nonylphenyl)phosphite, Diisodecyl pentaerythritol diphosphite, 9,10-dihydroxy-9-oxa-10-phosphaphenanthrene, 10-(3,5-di-tert-butyl-4-hydroxybenzyl)-9,10-dihydroxy-9-oxa-10-phosphaphenanthrene-10-oxide, 10-decyloxy-9,10-dihydroxy-9-oxa-10-phosphaphenanthrene, cyclic neopentanetetraylbis(2,4-di-tert-butylphenyl)phosphite, cyclic neopentanetetraylbis(2,6-di-tert-butyl-4-methylphenyl)phosphite, 2,2-methylenebis(4,6-di-tert-butylphenyl)octyl phosphite, 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-tert-butylanilino)-1,3,5-triazine, Octylated Diphenylamine Phosphate-based antioxidants such as Examples include:

[0047] Examples of singlet oxygen quenchers include carotenes, dyes, amines, phenols, nickel complexes, and sulfides, such as 1,4-diazabicyclo[2,2,2]octane (DABCO), β-carotene, 1,3-cyclohexadiene, 2-diethylaminomethylfuran, 2-phenylaminomethylfuran, 9-diethylaminomethylanthracene, 5-diethylaminomethyl-6-phenyl-3,4-dihydroxypyran, nickel dimethyldithiocarbamate, nickel 3,5-di-tert-butyl-4-hydroxybenzyl-O-ethylphosphonate, and nickel 3,5-di-tert-butyl-4-hydroxybenzyl-O-ethylphosphonate. Examples include t-butyl-4-hydroxybenzyl-O-butylphosphonate, nickel[2,2'-thiobis(4-tert-octylphenolate)]n-butylamine, nickel[2,2'-thiobis(4-tert-octylphenolate)]2-ethylhexylamine, nickel bis[2,2'-thiobis(4-tert-octylphenolate)], nickel bis[2,2'-sulfonebis(4-octylphenolate)], nickel bis(2-hydroxy-5-methoxyphenyl-Nn-butylaldimine), nickel bis(dithiobenzyl), nickel bis(dithiobiacetyl), and the like.

[0048] Examples of superoxide anion quenchers include complexes of superoxide dismutase with cobalt and nickel.

[0049] Examples of ozone quenchers include 4,4'-thiobis(6-tert-butyl-m-cresol), 2,4,6-tri-tert-butylphenol, 1,4-diazabicyclo[2,2,2]octane, N-phenyl-β-naphthylamine, α-tocopherol, 4,4'-methylene-bis(2,6-di-tert-butylphenol), P,P'-diaminodiphenylmethane, 2,2'-methylene-bis(6-tert-butyl-p-cresol), N,N'-diphenyl-p-phenylenediamine, N,N'-diphenylethylenediamine, and N-isopropyl-N'-phenyl-p-phenylenediamine.

[0050] The reversible thermochromic composition of the present invention is effective when used as is, but it can also be encapsulated in microcapsules to form a reversible thermochromic microcapsule pigment (hereinafter sometimes referred to as a "microcapsule pigment" or "pigment"), or dispersed in a thermoplastic resin or a thermosetting resin to form reversible thermochromic resin particles (hereinafter sometimes referred to as "resin particles"). The reversible thermochromic composition is preferably encapsulated in microcapsules to form a reversible thermochromic microcapsule pigment, because encapsulation in microcapsules makes it possible to form a chemically and physically stable pigment, and furthermore, the reversible thermochromic composition can maintain the same composition under various conditions of use, thereby achieving the same effects. Microencapsulation can be performed by any of the conventionally known methods, such as isocyanate-based interfacial polymerization, melamine-formalin-based or other in situ polymerization, liquid curing coating, phase separation from an aqueous solution, phase separation from an organic solvent, melt-dispersion cooling, air suspension coating, and spray drying, and is selected appropriately depending on the application. Furthermore, a secondary resin film can be provided on the surface of the microcapsules depending on the purpose to impart durability or modify the surface properties for practical use. The reversible thermochromic microcapsule pigment preferably has a mass ratio of inclusions to wall film of 7:1 to 1:1, and by having the mass ratio of inclusions to wall film within this range, a decrease in color density and vividness during color development is prevented.The mass ratio of inclusions to wall film is more preferably 6:1 to 1:1.

[0051] The average particle size of the reversible thermochromic microencapsulated pigment or resin particles is preferably 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 microencapsulated pigment or resin particles exceeds 50 μm, the dispersion stability and processability will be poor when blended into ink, paint, or resin. On the other hand, if the average particle size of the microencapsulated pigment or resin particles is less than 0.01 μm, it will be difficult to achieve high-concentration color development. The average particle size was measured by determining the particle area using image analysis particle size distribution measurement software (manufactured by Mountec Co., Ltd., product name: MacView), calculating the diameter equivalent to a circle with a projected area (Heywood diameter) from the area of ​​the particle area, and measuring the average particle size of particles equivalent to a sphere with the same volume using this value. Furthermore, if the particle size of all or the majority of particles exceeds 0.2 μm, it is also possible to measure the average particle size of particles equivalent to an equal volume sphere using the Coulter method using a particle size distribution analyzer (product name: Multisizer 4e, manufactured by Beckman Coulter, Inc.). Furthermore, the volumetric particle size and average particle size may be measured using a calibrated laser diffraction / scattering particle size distribution analyzer (manufactured by HORIBA, Ltd., product name: LA-960V2) based on values ​​measured using the software or a measuring device using the Coulter method.

[0052] A reversible thermochromic colorant such as a reversible thermochromic composition, a reversible thermochromic microcapsule pigment, or a resin particle is dispersed in a vehicle containing water and / or an organic solvent and, if necessary, various additives to form an ink composition (hereinafter, sometimes referred to as "ink"), which can be used as a reversible thermochromic liquid composition such as printing ink used in screen printing, offset printing, process printing, gravure printing, coater printing, pad printing, etc.; paint used in brush coating, spray coating, electrostatic coating, electrodeposition coating, flow coating, roller coating, dip coating, etc.; inkjet ink; ultraviolet-curable ink; ink for writing instruments such as marking pens, ballpoint pens, fountain pens, and brush pens; ink for applicators; ink for stamps; paints; cosmetics; and coloring liquids for textiles.

[0053] The reversible thermochromic liquid composition may contain various additives. Examples of additives include resins, crosslinking agents, curing agents, drying agents, plasticizers, viscosity modifiers, dispersants, ultraviolet absorbers, antioxidants, light stabilizers, anti-settling agents, smoothing agents, gelling agents, antifoaming agents, matting agents, penetrating agents, pH adjusters, foaming agents, coupling agents, moisturizing agents, antifungal agents, preservatives, and rust inhibitors.

[0054] Examples of the vehicle for a writing instrument used in the ink for a writing instrument include an oil-based vehicle containing an organic solvent, and an aqueous vehicle containing water and, if necessary, an organic solvent. Examples of organic solvents 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, ethylene 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, and N-methyl-2-pyrrolidone.

[0055] Examples of inks for writing instruments include shear thinning inks containing a shear thinning agent in the vehicle, and flocculating inks containing a polymer flocculant in the vehicle and suspending microcapsule pigments in a loosely flocculated state.

[0056] Inks containing a shear thinning agent in the vehicle (shear thinning inks) can suppress aggregation and sedimentation of microcapsule pigments and can also suppress bleeding of handwriting, allowing for the formation of good handwriting. Furthermore, when shear-thinning ink is stored in a ballpoint pen-shaped writing instrument, it can prevent ink leakage from the gap between the ball and the tip when the writing instrument is not in use, and it can prevent ink from flowing back when the writing tip is left facing upward (upright).

[0057] Examples of shear thinning agents include xanthan gum, welan gum, succinoglycan (average molecular weight: about 1,000,000 to 8,000,000), which is an organic acid-modified heteropolysaccharide whose constituent monosaccharides are glucose and galactose, alka gum, guar gum, locust bean gum and derivatives thereof, hydroxyethyl cellulose, alginic acid alkyl esters, polymers having a molecular weight of 100,000 to 150,000 and containing alkyl esters of methacrylic acid as the main component, glucomannan, thickening polysaccharides having gelling ability extracted from seaweed such as agar and carrageenan, benzylidene sorbitol and benzylidene xylitol or derivatives thereof, cross-linked acrylic acid polymers, inorganic substances, and the like. Examples of surfactants include nonionic surfactants with an HLB value of 8 to 12, such as fine particles, polyglycerin fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyethylene glycol fatty acid esters, polyoxyethylene castor oil, polyoxyethylene lanolin / lanonin alcohol / beeswax derivatives, polyoxyethylene alkyl ethers / polyoxypropylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, and fatty acid amides, salts of dialkyl or dialkenyl sulfosuccinic acid, mixtures of N-alkyl-2-pyrrolidone and anionic surfactants, and mixtures of polyvinyl alcohol and acrylic resins.

[0058] Ink containing a polymer flocculant in the vehicle (flocculant ink) can improve the dispersibility of the pigment because the microcapsule pigment forms loose aggregates via the polymer flocculant, preventing the microcapsule pigments from coming into contact with each other and agglomerating.

[0059] Examples of polymer flocculants include polyvinylpyrrolidone, polyethylene oxide, and water-soluble polysaccharides. Examples of water-soluble polysaccharides include tragacanth gum, guar gum, pullulan, cyclodextrin, and water-soluble cellulose derivatives. Furthermore, examples of water-soluble cellulose derivatives include methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethyl methyl cellulose, and hydroxypropyl methyl cellulose. Among the polymer flocculants, hydroxyethyl cellulose is preferred because of its excellent dispersibility.

[0060] Specific examples of polymer flocculants include those manufactured by Sumitomo Seika Chemicals Co., Ltd. under the product names HEC A grade, S grade, and CF grade; those manufactured by Daicel Phi-Chem Co., Ltd. under the product names HEC Daicel SP type, SE type, and EE type; those manufactured by Dow Chemical Japan under the product names CELLOSIZE WP type, QP type, and EP type; and those manufactured by Sansho Co., Ltd. under the product name SANHEC. The polymer flocculant is preferably blended in an amount of 0.1 to 1 mass %, more preferably 0.3 to 0.5 mass %, based on the total amount of ink. By blending within this range, the microencapsulated pigment forms loose aggregates, and the effect of improving the dispersibility of the pigment can be fully exerted.

[0061] Furthermore, the dispersibility of the microcapsule pigment can be improved by blending a dispersant into the ink. In addition, a polymer flocculant and a dispersant can be used in combination. When both are used in combination, the dispersibility of the microencapsulated pigment can be improved, and the dispersibility of the loose aggregates of the microencapsulated pigment formed via the polymer flocculant can be further improved.

[0062] Examples of dispersants include synthetic resins such as polyvinylpyrrolidone, polyvinyl butyral, polyvinyl ether, styrene-maleic acid copolymer, ketone resin, hydroxyethyl cellulose and its derivatives, and styrene-acrylic acid copolymer, acrylic polymers, PO·EO adducts, and polyester amine oligomers. Among the above dispersants, acrylic polymer dispersants are preferred because they have excellent dispersibility for microencapsulated pigments, acrylic polymer dispersants having carboxyl groups are more preferred, and acrylic polymer dispersants having a comb structure and having carboxyl groups on the side chains are even more preferred. A particularly preferred dispersant is an acrylic polymer dispersant with a comb structure having multiple carboxyl groups in the side chains, and a specific example is Solsperse 43000, a product manufactured by Lubrizol Japan Co., Ltd. The dispersant is preferably blended in an amount of 0.01 to 2% by mass, more preferably 0.1 to 1.5% by mass, based on the total amount of ink. If the blending ratio of dispersant exceeds 2% by mass, the microencapsulated pigment is likely to settle or float when subjected to external vibrations, etc. On the other hand, if the blending ratio of dispersant is less than 0.01% by mass, the effect of improving dispersibility is less likely to be achieved.

[0063] Furthermore, by incorporating a specific gravity adjuster into the ink, when the viscosity of the vehicle is low, it is possible to prevent the microcapsule pigment from settling or floating up in the ink and becoming localized when the ink is subjected to external stimuli such as vibration.

[0064] The specific gravity of a microencapsulated pigment depends on the particle size of the microencapsulated pigment, the components and their contents encapsulated in the microcapsules, the components and film thickness of the capsule wall membrane, the coloration state of the microencapsulated pigment, and the temperature, but the specific gravity is preferably in the range of 1.05 to 1.20, more preferably 1.10 to 1.20, and even more preferably 1.12 to 1.15, when the microencapsulated pigment is in a fully colored state and water is used as the reference substance in an environment of 20°C. Furthermore, microencapsulated pigments with a large hysteresis width (ΔH) often use a component (c) having two or more aromatic rings in the molecule, and have the above-mentioned high specific gravity. However, in inks containing a specific gravity adjuster, even if the vehicle viscosity is low, the microencapsulated pigment is prevented from settling or floating in the ink when subjected to external influences such as vibration during transportation. The specific gravity of the microcapsule pigment can be measured by the following method. Method for measuring the specific gravity of microcapsule pigments 1. 30 ml of glycerin aqueous solution and 1 g of fully colored microcapsule pigment are placed in a screw cap bottle and mixed to obtain a microcapsule pigment dispersion. 2. 30 ml of the microcapsule pigment dispersion is adjusted to 20°C and centrifuged at 1000 rpm for 30 seconds. A refrigerated tabletop centrifuge (manufactured by Kokusan Co., Ltd., product name: H103N) can be used as the centrifuge. 3. Observe the microcapsule pigment dispersion. If most of the microcapsule pigment has settled to the bottom of the beaker, repeat steps 1 and 2 using an aqueous solution with a higher glycerin concentration than the glycerin aqueous solution used at this time, and observe the state of the dispersion. If it is confirmed that most of the microcapsule pigment is floating on the liquid surface, repeat steps 1 and 2 using an aqueous solution with a lower glycerin concentration than the glycerin aqueous solution used this time, and observe the state of the dispersion. The above series of operations is repeated until it is visually confirmed that the majority of the microencapsulated pigment does not float to the surface or settle, but that the glycerin aqueous solution is uniformly colored except for the surface and the area near the bottom of the screw cap bottle. When this state is observed, the specific gravity of the glycerin aqueous solution is measured and used as the specific gravity of the microencapsulated pigment. The specific gravity of the glycerin aqueous solution can be measured by the hydrometer method described in JIS K0061, Section 7.1, using an aqueous solution adjusted to 20°C.

[0065] The settling and floating stability of the pigment is maximized when the difference in specific gravity between the vehicle and the pigment is minimal, and the specific gravity adjuster brings the specific gravity of the vehicle closer to that of the microencapsulated pigment. The specific gravity of the vehicle depends on the specific gravity of the water-soluble substance dissolved in the vehicle and the amount added. Therefore, adding and dissolving a larger amount of a specific gravity adjuster with a larger specific gravity in the vehicle makes it possible to increase the specific gravity of the vehicle.

[0066] Examples of specific gravity adjusters include those that dissolve in the vehicle and adjust the specific gravity of the vehicle to approach the specific gravity of the microcapsule pigment, such as oxyacids of Group 6 elements with atomic weights in the range of 90 to 185 and their salts. The oxygen acid and its salt are selected from the group consisting of oxygen acids of transition metal elements and their salts, and the oxygen acid ions are said to form tetrahedrons or octahedrons in which oxygen atoms are usually 4- or 6-coordinated to metal atoms, etc. The tetrahedral or octahedral units may be single units, or may be polyacids having a structure in which they are bonded via edges or vertices, and their salts, called polyacid salts. Polyacids are polyacids formed by the condensation of oxyacids of metal elements, but polyacids composed of only one type of metal and in which all the condensed anions are of the same type are called isopolyacids, and polyacids in which two or more types of anions are condensed are called heteropolyacids. The respective salts are called isopolyacid salts and heteropolyacid salts. The above polyacids include isopolyacids, heteropolyacids, etc., and the above polyacid salts include isopolyacids, heteropolyacids, etc.

[0067] Examples of the specific gravity adjuster include a single oxygen acid and its salt, an isopoly acid and its salt, and a heteropoly acid and its salt. Examples of the single oxygen acid include molybdic acid and tungstic acid, and examples of the salt of the single oxygen acid include sodium molybdate, potassium molybdate, ammonium molybdate, sodium tungstate, potassium tungstate, ammonium tungstate, lithium tungstate, and magnesium tungstate. Examples of isopolyacids include metamolybdic acid, paramolybdic acid, metatungstic acid, paratungstic acid, and isotungstic acid. Furthermore, examples of isopolyacid salts include sodium metamolybdate, potassium metamolybdate, ammonium metamolybdate, sodium paramolybdate, potassium paramolybdate, ammonium paramolybdate, sodium metatungstate, potassium metatungstate, ammonium metatungstate, barium metatungstate, sodium paratungstate, and sodium isotungstate. Examples of heteropolyacids include molybdophosphoric acid, molybdosilicic acid, tungstophosphoric acid, and tungstosilicic acid, and examples of heteropolyacid salts include sodium molybdophosphate, sodium molybdosilicate, sodium tungstophosphate, and sodium tungstosilicate. The oxygen acids and salts thereof may be used alone or in combination of two or more.

[0068] Among the specific gravity adjusters, metatungstic acid, paratungstic acid, sodium metatungstate, potassium metatungstate, ammonium metatungstate, barium metatungstate, sodium paratungstate, sodium isotungstate, tungstophosphoric acid, tungstosilicic acid, sodium tungstophosphate, and sodium tungstosilicate are preferred, and sodium isotungstate, sodium metatungstate, and sodium paratungstate are more preferred. The sodium isotungstate, sodium metatungstate, and sodium paratungstate are not only highly safe but also have a high specific gravity themselves, and therefore, it is easy to adjust the liquid to have a high specific gravity depending on the amount added, and are therefore preferable.

[0069] The gravity adjuster is preferably blended in an amount of 2 to 20% by mass, more preferably 5 to 15% by mass, based on the total amount of ink. If the blending ratio of the gravity adjuster exceeds 20% by mass, the microcapsule pigment tends to aggregate. On the other hand, if the blending ratio of the gravity adjuster is less than 2% by mass, the effect of adjusting the vehicle's specific gravity is reduced. The mass ratio of the microcapsule pigment to the specific gravity adjuster is preferably 1:0.05 to 4.0, more preferably 1:0.075 to 2.0, and even more preferably 1:0.1 to 1.5.

[0070] When the vehicle for the writing instrument is an aqueous vehicle, the vehicle contains at least water, and the amount of water is preferably 30 to 80% by mass, more preferably 40 to 70% by mass, based on the total amount of the ink. Furthermore, by blending a water-soluble organic solvent into the ink, evaporation of water from the ink is suppressed, fluctuations in the specific gravity of the vehicle are prevented, and good dispersion stability of the microencapsulated pigment is maintained, while the structure of the polymer flocculant or the loose aggregates formed by the polymer flocculant and the dispersant can be stabilized. Examples of water-soluble organic solvents include ethanol, propanol, butanol, glycerin, sorbitol, triethanolamine, diethanolamine, monoethanolamine, ethylene glycol, diethylene glycol, thioethylene glycol, polyethylene glycol, propylene glycol, butylene glycol, ethylene glycol monomethyl ether, ethylene 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, and N-methyl-2-pyrrolidone. When the hysteresis width (ΔH) of the microencapsulated pigment to be incorporated into the ink is large, the specific gravity of the microencapsulated pigment is greater than 1. Therefore, when adjusting the specific gravity of the vehicle, using a water-soluble organic solvent with a specific gravity greater than that of water makes it easier to adjust the specific gravity. Therefore, a water-soluble organic solvent such as glycerin with a specific gravity greater than 1.1 is preferred.

[0071] The water-soluble organic solvent is preferably blended in an amount of 1 to 40% by mass, more preferably 5 to 30% by mass, and even more preferably 10 to 25% by mass, based on the total amount of ink. If the blending ratio of the water-soluble organic solvent exceeds 40% by mass, the dissolution stability of the specific gravity adjuster is likely to decrease. On the other hand, if the blending ratio of the water-soluble organic solvent is less than 1% by mass, the effect of suppressing water evaporation is poor.

[0072] Furthermore, when the writing instrument ink is used in a ballpoint pen, it is preferable to add to the ink a lubricant such as a higher fatty acid such as oleic acid, a nonionic surfactant having a long-chain alkyl group, a polyether-modified silicone oil, a thiophosphite triester such as thiophosphite tri(alkoxycarbonylmethyl ester) or thiophosphite tri(alkoxycarbonylethyl ester), a polyoxyethylene alkyl ether or polyoxyethylene alkylaryl ether phosphate monoester, a polyoxyethylene alkyl ether or polyoxyethylene alkylaryl ether phosphate diester, or a metal salt, ammonium salt, amine salt, or alkanolamine salt thereof to prevent wear of the ball seat.

[0073] In addition, various additives such as a pH adjuster, a rust inhibitor, an antiseptic, or an antifungal agent may be added as needed. Examples of pH adjusters include inorganic salts such as sodium carbonate, sodium phosphate, and sodium acetate, and organic basic compounds such as water-soluble amine compounds. Examples of the rust inhibitor include benzotriazole, tolyltriazole, dicyclohexylammonium nitrite, diisopropylammonium nitrite, and saponin. Examples of antiseptics or antifungal agents include carbolic acid, sodium salt of 1,2-benzthiazolin-3-one, sodium benzoate, sodium dehydroacetate, potassium sorbate, propyl parahydroxybenzoate, and 2,3,5,6-tetrachloro-4-(methylsulfonyl)pyridine. Other additives include urea, nonionic surfactants, reduced or non-reduced starch hydrolysates, oligosaccharides such as trehalose, wetting agents such as sucrose, cyclodextrin, glucose, dextrin, sorbitol, mannitol, and sodium pyrophosphate, antifoaming agents, dispersants, fluorine-based surfactants that improve the penetration of ink, and nonionic surfactants.

[0074] The ink contains a reversible thermochromic microencapsulated pigment in an amount of preferably 5 to 40% by mass, more preferably 10 to 40% by mass, and even more preferably 10 to 30% by mass, based on the total mass of the ink. By containing the microencapsulated pigment in this range, the desired color density can be obtained and a decrease in ink outflow properties can be prevented.

[0075] The ink composition according to the present invention can be produced by any conventional method, specifically by blending the required amounts of the above-described components and mixing them with various stirrers such as a propeller stirrer, a homodisper, or a homomixer, or various dispersers such as a bead mill.

[0076] When the ink for a writing instrument according to the present invention is used in a ballpoint pen, its viscosity is 3.84 s under an environment of 20°C. -1 When measured under these conditions, the viscosity is preferably in the range of 1 to 2000 mPa·s, more preferably 3 to 1500 mPa·s, and even more preferably 500 to 1000 mPa·s, because this can prevent the microencapsulated pigment from settling or flocculating. -1 When measured under the above conditions, the viscosity is preferably in the range of 1 to 200 mPa·s, more preferably 10 to 100 mPa·s, and even more preferably 20 to 50 mPa·s, because this allows for good ink discharge from the pen tip of a ballpoint pen. By having the viscosity within the above range, it is possible to maintain high levels of dispersion stability of the microencapsulated pigment and free flow of the ink within the mechanism of the ballpoint pen. The viscosity was measured using a digital viscometer (Brookfield, product name: DV-II, cone rotor (CPE-42)) at a shear rate of 3.84 sec. at 20°C. -1 (1 rpm), or shear rate 384 sec -1 Measurement can be performed under the condition of (100 rpm).

[0077] When the writing instrument ink according to the present invention is used in a marking pen, its viscosity, when measured at a rotation speed of 6 rpm in an environment of 20°C, is preferably in the range of 3 to 25 mPa·s, more preferably 4 to 20 mPa·s, and even more preferably 5 to 15 mPa·s. When measured at a rotation speed of 12 rpm, it is preferably in the range of 2 to 20 mPa·s, more preferably 3 to 15 mPa·s, and even more preferably 4 to 15 mPa·s. When measured at a rotation speed of 30 rpm, it is preferably in the range of 1 to 20 mPa·s, more preferably 2 to 15 mPa·s, and even more preferably 3 to 10 mPa·s. Having a viscosity within the above ranges can improve the fluidity of the ink and the dispersion stability of the microencapsulated pigment. The viscosity can be measured by placing the ink in an environment of 20°C using a BL type rotational viscometer (manufactured by Toki Sangyo Co., Ltd., product name: TVB-M type viscometer, B type rotor).

[0078] The writing implements, such as ballpoint pens and marking pens, that contain the ink for the writing implement will now be described. When filling a ballpoint pen, the structure and shape of the ballpoint pen itself are not particularly limited, and an example is a ballpoint pen that has an ink reservoir tube filled with shear-thinning ink inside the barrel, the ink reservoir tube communicating with a ballpoint pen tip having a ball attached to the tip, and further has a liquid plug tightly attached to the end face of the ink to prevent backflow. Examples of ballpoint pen tips include tips in which the ball is held in a ball-holding portion formed by deforming the area near the tip of a metal pipe by pressing it inward from the outer surface; tips in which the ball is held in a ball-holding portion formed by cutting a metal material with a drill or the like; tips in which a resin ball receiving seat is provided inside a metal or plastic tip; and tips in which the ball held in the tip is urged forward by a spring. The material of the ballpoint pen tip and ball is not particularly limited, and examples thereof include cemented carbide (super hard), stainless steel, ruby, ceramic, resin, rubber, and the like. The diameter of the ball is preferably about 0.3 to 2.0 mm, more preferably about 0.3 to 1.5 mm, and even more preferably about 0.3 to 1.0 mm.

[0079] The ink reservoir tube may be a molded body made of a thermoplastic resin such as polyethylene, polypropylene, polyethylene terephthalate, or nylon, or a tubular body made of metal. The ink reservoir may be directly connected to the tip, or the ink reservoir and the tip may be connected via a connecting member. In addition, the ink reservoir tube may be in the form of a refill, with the refill contained in a barrel made of resin, metal, etc., or the barrel itself with a tip attached to the tip may serve as the ink reservoir, with ink being filled directly into the barrel.

[0080] Furthermore, when storing ink in a retractable ballpoint pen, the structure and shape of the retractable ballpoint pen are not particularly limited, and any structure can be used as long as the writing tip provided on the ballpoint pen refill is stored within the barrel while exposed to the outside air, and the writing tip protrudes from the barrel opening when the retractable mechanism is activated. Examples of retraction mechanisms include: (1) a side-slide retraction mechanism in which an operating part (clip) that can move back and forth in the radial direction protrudes radially outward from the rear side wall of the barrel, and the writing tip is retracted from the front end opening of the barrel by sliding the operating part forward; (2) a rear-end knock retraction mechanism in which the operating part at the rear end of the barrel is pressed forward to cause the writing tip to retract from the front end opening of the barrel; (3) a side-knock retraction mechanism in which the operating part that protrudes from the outer surface of the barrel side wall is pressed radially inward to cause the writing tip to retract from the front end opening of the barrel; and (4) a rotary retraction mechanism in which the operating part at the rear of the barrel is rotated to cause the writing tip to retract from the front end opening of the barrel. The retractable ballpoint pen may be a composite type retractable ballpoint pen that contains a plurality of ballpoint pen refills in the barrel and that causes the writing tip of one of the ballpoint pen refills to protrude and retract from the front end opening of the barrel by operating the retractable mechanism.

[0081] An ink backflow preventer is placed at the rear end of the ink filled in the ink reservoir tube. The ink backflow preventive composition comprises a non-volatile liquid or a hardly-volatile liquid, examples of which include petrolatum, spindle oil, castor oil, olive oil, refined mineral oil, liquid paraffin, polybutene, α-olefin, α-olefin oligomer or co-oligomer, dimethyl silicone oil, methylphenyl silicone oil, amino-modified silicone oil, polyether-modified silicone oil, fatty acid-modified silicone oil, etc. The ink backflow preventive composition may be used alone or in combination of two or more kinds.

[0082] It is preferable to thicken the non-volatile liquid and / or the hardly-volatile liquid to a suitable viscosity by adding a thickener. Examples of thickeners include clay-based thickeners such as silica whose surface has been hydrophobically treated, fine particle silica whose surface has been methylated, aluminum silicate, swellable mica, and hydrophobically treated bentonite and montmorillonite; fatty acid metal soaps such as magnesium stearate, calcium stearate, aluminum stearate, and zinc stearate; tribenzylidene sorbitol, fatty acid amides, amide-modified polyethylene wax, hydrogenated castor oil, dextrin-based compounds such as fatty acid dextrins; and cellulose-based compounds. Furthermore, the liquid ink backflow preventive composition and the solid ink backflow preventive composition may be used in combination.

[0083] When filling a marking pen, the structure and shape of the marking pen itself are not particularly limited, and examples include a marking pen in which an ink absorbing body made of a fiber bundle is built into the barrel, and a marking pen tip made of a fiber processed body with capillary gaps formed therein is attached to the barrel directly or via an intermediate member, and the ink absorbing body and the tip are connected, and the ink absorbing body of the marking pen is impregnated with cohesive ink, and a marking pen in which the tip and an ink reservoir tube are arranged via a valve body that opens when the tip is pressed, and the ink is directly stored in the ink reservoir tube.

[0084] Examples of marking pen tips include conventional porous members with interconnected pores, such as resin-processed fibers, fused heat-melting fibers, and felt, which have a porosity selected from a range of approximately 30 to 70%, and one end of which can be processed into a shape suitable for the purpose, such as a bullet shape, a rectangle, or a chisel shape, for practical use.

[0085] The ink occlusion body is made by bundling crimped fibers in the longitudinal direction, and is contained within a covering body such as a plastic cylinder or film, with the porosity adjusted to a range of approximately 40 to 90%.

[0086] The valve element may be of a conventional, general-purpose pumping type, but it is preferable to use one with a spring pressure that can be pressed and released by the pressure of the writing pen.

[0087] Furthermore, the shape of the ballpoint pen or marking pen is not limited to those described above, but may be a composite writing instrument (double-headed, tip-dispensing, etc.) equipped with tips of different shapes or with pen tips that dispense inks of different colors.

[0088] The handwriting obtained by writing on a surface to be written on using a writing instrument containing the ink for a writing instrument can be discolored by rubbing with a finger or by using a heating or cooling tool. Examples of the heating tool include an electrically heated color-changing tool equipped with a resistance heating element such as a PTC element, a heat-changing tool filled with a medium such as hot water, a heat-changing tool using steam or laser light, and the application of a hair dryer. A friction member is preferably used because it can change color in a simple manner. Examples of cooling devices include electrically operated thermochromic devices using a Peltier element, thermochromic devices filled with a refrigerant such as cold water or ice chips, refrigerants, refrigerators, freezers, and the like.

[0089] The friction member is preferably an elastic material such as an elastomer or plastic foam, which has a high elasticity and can generate frictional heat by generating appropriate friction when rubbed. Although a general eraser for erasing pencil marks may be used to rub the marks, the rub generates eraser dust, and therefore the friction member described above, which generates almost no eraser dust, is preferably used. Examples of the material for the friction member include silicone resin, SEBS resin (styrene-ethylene-butadiene-styrene block copolymer), and polyester resin.

[0090] Furthermore, a writing instrument set can be obtained by combining a writing instrument with a friction member (friction body) of any shape that is separate from the writing instrument, but by providing the friction member on the writing instrument, the writing instrument can be made more portable. In the case of a writing instrument with a cap, the location where the friction member is provided is not particularly limited; for example, the cap itself may be formed from a friction member, the barrel itself may be formed from a friction member, or if a clip is provided, the clip itself may be formed from a friction member, or the friction member may be provided at the tip (top) of the cap or the rear end of the barrel (the part where the writing tip is not provided). In the case of a retractable writing instrument, the location where the friction member is provided is not particularly limited; for example, the barrel itself may be formed from a friction member, or if a clip is provided, the clip itself may be formed from a friction member, or the friction member may be provided near the opening of the barrel, at the rear end of the barrel (the part where the writing tip is not provided), or at the knock portion.

[0091] The ink can also be used as a stamp ink. Water is used as the medium for the ink for stamping, but a water-soluble organic solvent can also be used if necessary. Examples of water-soluble organic solvents include glycols such as glycerin, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 1,3-butylene glycol, and ethylene glycol monomethyl ether, as well as lower alkyl ethers thereof, 2-pyrrolidone, N-vinylpyrrolidone, and urea. When a reversible thermochromic microcapsule pigment is used in a stamp ink, glycerin and propylene glycol are preferred among the above-mentioned water-soluble organic solvents.

[0092] The water-soluble organic solvent is preferably blended in an amount of 30 to 60% by mass, more preferably 30 to 55% by mass, and even more preferably 40 to 50% by mass, based on the total amount of the ink. By having the blending ratio of the water-soluble organic solvent within this range, the ink will not dry out or absorb moisture, making it easier to obtain a clear printed image. If the blending ratio of the water-soluble organic solvent exceeds 60% by mass, the moisture absorption tends to increase, and the printed image tends to bleed or become mottled, making it difficult to obtain a clear printed image. On the other hand, if the blending ratio of the water-soluble organic solvent is less than 30% by mass, the printed surface tends to dry out, and the printed image tends to fade, making it difficult to obtain a clear printed image.

[0093] In addition to the water-soluble organic solvent, an organic solvent can also be used as the medium. Examples of organic solvents include cellosolve-based solvents such as castor oil fatty acid alkyl esters, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, and ethyl cellosolve acetate; ethylene glycol acetate, ethylene glycol diethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether, dipropylene glycol monomethyl ether acetate, and tripropylene glycol monomethyl ether; Alkyl glycol solvents, ethyl formate, amyl formate, ethyl acetate, ethyl acetoacetate, propyl acetate, butyl acetate, 3-methyl-3-methoxybutyl acetate, amyl acetate, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, propyl-3-methoxypropionate, butyl-3-methoxypropionate, methyl lactate, ethyl lactate, ethyl-2-hydroxybutyrate, butyl butyrate, butyl stearate, ethyl caprylamide Ester solvents such as plate, diethyl oxalate, ethyl pyruvate, ethyl benzoate, etc.; hydrocarbon solvents such as n-pentane, n-hexane, n-octane, n-dodecane, diisobutylene, dipentene, hexene, methylcyclohexene, bicyclohexyl, mineral spirits, etc.; halogenated hydrocarbon solvents such as amyl chloride and butyl chloride, alcohol solvents such as 3-methoxy-3-methylbutanol and 3-methoxy-3-methylpentanol, diethyl ether, dipropyl ether, ethyl isobutyl ether, dibutyl ether,Examples of such solvents include ether solvents such as diisopropyl ether, diamyl ether, and dihexyl ether; ketone solvents such as acetone, methyl ethyl ketone, methyl isopropyl ketone, methyl butyl ketone, methyl isobutyl ketone, methyl isoamyl ketone, ethyl amyl ketone, methyl hexyl ketone, methyl nonyl ketone, diisopropyl ketone, diisobutyl ketone, methoxymethyl pentanone, and cyclohexanone; propionic acid solvents such as 3-methoxypropionic acid and 3-ethoxypropionic acid; highly polar solvents such as dimethylformamide, dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, and benzonitrile; and mixed solvents thereof.

[0094] Furthermore, a thickener may be added to the ink. Examples of thickeners include xanthan gum, welan gum, succinoglycan (average molecular weight: about 1,000,000 to 8,000,000), which is an organic acid-modified heteropolysaccharide whose constituent monosaccharides are glucose and galactose, guar gum, locust bean gum and derivatives thereof, hydroxyethyl cellulose, alginic acid alkyl esters, polymers having a molecular weight of 100,000 to 150,000 and containing an alkyl ester of methacrylic acid as the main component, glycomannan, thickening polysaccharides having gelling ability extracted from seaweed such as agar and carrageenin, benzylidene sorbitol and benzylidene xylitol, or mixtures thereof. Examples of surfactants include derivatives thereof, crosslinkable acrylic acid polymers, inorganic fine particles, polyglycerin fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyethylene glycol fatty acid esters, polyoxyethylene castor oil, polyoxyethylene lanolin / lanolin alcohol / beeswax derivatives, polyoxyethylene alkyl ethers / polyoxypropylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, nonionic surfactants having an HLB value of 8 to 12 such as fatty acid amides, and salts of dialkyl or dialkenyl sulfosuccinic acid. Among the above thickeners, alkali-soluble acrylic emulsions are preferred. When an alkali-soluble acrylic emulsion is used as a thickener, the pH of the ink is adjusted to preferably 6-11, more preferably 7-11, and even more preferably 7-10.

[0095] Furthermore, by adding a binder resin to the ink, it is possible to improve the adhesion of the printed image and adjust the viscosity of the ink. Examples of the binder resin include a resin emulsion, an alkali-soluble resin, and a water-soluble resin. Examples of resin emulsions include aqueous dispersions of polyacrylic acid esters, styrene-acrylic acid copolymers, polyvinyl acetate, ethylene-vinyl acetate copolymers, ethylene-vinyl chloride copolymers, methacrylic acid-maleic acid copolymers, ethylene-methacrylic acid copolymers, α-olefin-maleic acid copolymers, polyesters, polyurethanes, and the like. Examples of alkali-soluble resins include styrene-maleic acid copolymers, ethylene-maleic acid copolymers, and styrene-acrylic acid copolymers. Examples of the water-soluble resin include polyvinyl alcohol and polyvinyl butyral. The resin emulsions may be used alone or in combination of two or more.

[0096] In addition, various additives such as a pH adjuster, a preservative, or an antifungal agent may be added as needed. Examples of pH adjusters include inorganic salts such as ammonia, sodium carbonate, sodium phosphate, sodium hydroxide, and sodium acetate, and organic basic compounds such as water-soluble amine compounds such as triethanolamine and diethanolamine. Examples of antiseptics or antifungal agents include carbolic acid, sodium salt of 1,2-benzisothiazolin-3-one, sodium benzoate, sodium dehydroacetate, potassium sorbate, propyl parahydroxybenzoate, and 2,3,5,6-tetrachloro-4-(methylsulfonyl)pyridine. Other additives include fluorine-based surfactants, nonionic surfactants, anionic surfactants, cationic surfactants, dimethylpolysiloxane, and the like, which improve the permeability of the solvent.

[0097] If necessary, resins such as acrylic resins, styrene-maleic acid copolymers, cellulose derivatives, polyvinylpyrrolidone, polyvinyl alcohol, and dextrin can be added to impart adhesiveness and viscosity to the paper surface.

[0098] Additionally, rust inhibitors such as benzotriazole, tolyltriazole, dicyclohexylammonium nitrite, diisopropylammonium nitrite, and saponin, urea, nonionic surfactants, reduced or non-reduced starch hydrolysates and oligosaccharides such as trehalose, wetting agents such as sucrose, cyclodextrin, glucose, dextrin, sorbitol, mannitol, and sodium pyrophosphate, antifoaming agents, dispersants, fluorine-based surfactants that improve the penetration of ink, and nonionic surfactants may also be blended.

[0099] The ink contains a reversible thermochromic microencapsulated pigment in an amount of preferably 10 to 40% by mass, more preferably 10 to 35% by mass, and even more preferably 10 to 30% by mass, based on the total mass of the ink. If the amount of the microencapsulated pigment exceeds 40% by mass, the dispersion stability of the microencapsulated pigment in the ink tends to decrease. On the other hand, if the amount of the microencapsulated pigment is less than 10% by mass, the color density tends to decrease.

[0100] The ink for stamps can be used as ink for stamp pads and ink for stamps provided with a stamp material having continuous pores. For example, a stamp pad can be impregnated with ink to obtain a stamp pad that supplies ink to the printing surface of a stamp that comes into contact with it.Also, a stamp can be obtained by impregnating ink into a stamp material having continuous pores.

[0101] A stamp equipped with a printing material with interconnected pores is made by impregnating ink into a rubber-like elastic material with interconnected pores, and when it is pressed against a surface to be stamped, the ink transfers to the surface through the openings of the interconnected pores, transferring the surface shape of the stamp. Areas where transfer is not desired are recessed, or the openings are blocked to prevent ink from adhering to the surface to be stamped. The surface shape of the stamp may include a date, a symbol, or text such as "Confidential," "Completed," or "Received."

[0102] The stamp material having interconnected pores is housed in a stamp base material so that the stamp surface is exposed, and the exposed surface is preferably provided with a cap to prevent the ink from drying out when not in use or to prevent contamination due to accidental contact. In addition, an ink reservoir for supplying ink to the printing material may be provided at the rear of the printing material having continuous pores, thereby increasing the number of times the printing can be performed.

[0103] In addition, the printing material may be impregnated with ink beforehand and attached to the stamp, or the printing material of the stamp to which the printing material is attached may be impregnated with ink. When the ink is impregnated into the stamp material to which the stamp material is attached, the ink may be impregnated from the front surface of the stamp material or from the rear surface of the stamp material. Similarly, in the case of a stamp having an ink reservoir, the ink reservoir may be filled with ink beforehand and attached to the stamp, or the ink reservoir of a stamp provided with a printing material and an ink reservoir may be filled with ink.

[0104] The stamp can form an image on various surfaces. Furthermore, the image formed by the stamp ink can be discolored by rubbing it with a finger or by applying the heating or cooling tool described above. The friction member described above is preferred as the heating tool, as it can be discolored in a simple manner.

[0105] A stamp set can also be obtained by combining a stamp with a friction member (friction body) of any shape that is separate from the stamp, but by providing the above-mentioned friction member on the stamp, it can be made more portable.

[0106] When applying or printing the reversible thermochromic liquid composition, the material of the support is not particularly limited and all materials are effective, such as paper, synthetic paper, fiber, fabric, synthetic leather, leather, plastic, glass, ceramic material, metal, wood, stone, etc. The shape of the support is not limited to a flat surface, but may be uneven. A reversible thermochromic laminate (reversible thermochromic printed matter) can be obtained by providing a reversible thermochromic layer containing a reversible thermochromic colorant such as a reversible thermochromic composition, a reversible thermochromic microcapsule pigment, or resin particles on a support. In the case where a non-thermochromic colored layer (non-thermochromic image) is pre-formed on the support, the colored layer or image can be made to appear or disappear by the reversible thermochromic layer due to a change in temperature, further diversifying the manner of change.

[0107] Furthermore, a reversible thermochromic colorant such as a reversible thermochromic composition, a reversible thermochromic microcapsule pigment, or a resin particle can be melt-blended with an excipient and molded to form a reversible thermochromic solid molded article for application, which can be used as a solid writing material or a solid cosmetic. Examples of solid writing materials include crayons, pencil leads, mechanical pencil leads, solid gel markers, and the like. Examples of solid cosmetics include foundation, eyeliner, eyebrow pencil, eyeshadow, lipstick, etc.

[0108] Examples of excipients used in solid writing materials include waxes, gelling agents, clays, and the like. The wax is not particularly limited as long as it is a conventionally known wax, and examples thereof include carnauba wax, Japan wax, beeswax, microcrystalline wax, montan wax, candelilla wax, sucrose fatty acid ester, dextrin fatty acid ester, polyolefin wax, styrene-modified polyolefin wax, and paraffin wax. The gelling agent is not particularly limited as long as it is a conventionally known agent, and examples thereof include 12-hydroxystearic acid, dibenzylidene sorbitols, tribenzylidene sorbitols, amino acid oils, and alkali metal salts of higher fatty acids. Examples of clay minerals include kaolin, bentonite, and montmorillonite.

[0109] Among the above-mentioned excipients, it is preferable to contain at least one of polyolefin wax, sucrose fatty acid ester, and dextrin fatty acid ester, as these excipients are likely to improve the density of handwriting. Examples of polyolefin waxes include waxes such as polyethylene, polypropylene, polybutylene, α-olefin polymers, ethylene-propylene copolymers, and ethylene-butene copolymers. As the sucrose fatty acid ester, an ester having a fatty acid having 12 to 22 carbon atoms as a constituent fatty acid is preferred, and palmitic acid and stearic acid are more preferred. Specific examples of sucrose fatty acid esters include those manufactured by Mitsubishi Chemical Foods Corporation under the product name Ryoto Sugar Ester Series, and those manufactured by Daiichi Kogyo Seiyaku Co., Ltd. under the product name Sugar Wax Series.

[0110] The filler 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 writing material. When the blending ratio of the filler is within the above range, the shape of the solid writing material can be easily obtained, and the writing density of the solid writing material can easily be increased. If the blending ratio of the excipient exceeds 70% by mass, it becomes difficult to obtain sufficient writing density, whereas if the blending ratio of the excipient is less than 0.2% by mass, it becomes difficult to obtain a shape suitable for a writable core material.

[0111] Furthermore, by blending a filler into the solid writing material, it is possible to improve the strength of the solid writing material and adjust the writing feel. Examples of the filler include talc, clay, silica, calcium carbonate, barium sulfate, alumina, mica, boron nitride, potassium titanate, and glass flakes. Among the above fillers, talc or calcium carbonate is preferred because it has excellent moldability and is less likely to impair thermochromic properties when a microcapsule pigment is used. The filler is preferably blended in the range of 10 to 65% by mass based on the total amount of the solid writing material. If the blending ratio of the filler exceeds 65% by mass, the color development and writing feel tend to deteriorate. On the other hand, if the blending ratio of the filler is less than 10% by mass, the strength of the solid writing material tends to deteriorate.

[0112] Furthermore, by blending a binder resin into the solid writing material, the strength of the solid writing material can be improved. Examples of binder resins include natural resins and synthetic resins, such as olefin resins, cellulose resins, vinyl alcohol resins, pyrrolidone resins, acrylic resins, styrene resins, amide resins, and basic group-containing resins. Among the binder resins, ethylene-vinyl acetate copolymer resin, ethylene-vinyl alcohol copolymer resin, and polyvinyl alcohol resin are preferred, and molding stability can be improved by using these resins in combination with polyester polyol resin. The binder resin is preferably blended in the range of 0.5 to 5% by mass based on the total amount of the solid writing material.

[0113] Furthermore, by incorporating a hindered amine compound into the solid writing material, it is possible to make afterimages of erased writing on the writing surface less visible, thereby ensuring rewritability without impairing the appearance of the writing surface and improving marketability. The hindered amine compound preferably has a molecular weight of 1000 or less, since it is highly compatible with other components, does not easily bleed out, and can form clear handwriting even after the passage of time. The melting point is preferably 120° C. or lower. A low melting point allows the solid writing material to be produced without applying excessive heat during production, and prevents deterioration of the reversible thermochromic colorant contained in the solid writing material, such as a reversible thermochromic composition, a reversible thermochromic microcapsule pigment, or resin particles.

[0114] In addition, various additives may be added as needed. Examples of the additives include viscosity adjusters, antifungal agents or preservatives, antibacterial agents, ultraviolet inhibitors, antioxidants, lubricants, and fragrances.

[0115] The solid writing material can be used to write on various writing surfaces, and furthermore, since it uses a reversible thermochromic colorant such as a reversible thermochromic composition, a reversible thermochromic microcapsule pigment, or resin particles, the handwriting obtained by writing on the writing surface can be discolored by rubbing with a finger or by applying the above-mentioned heating or cooling tool. As the heating tool can be discolored by a simple method, the above-mentioned friction member is preferred.

[0116] Although a solid writing body set can be obtained by combining a solid writing body with a friction member (friction body) of any shape that is separate from the solid writing body, a solid writing body set with excellent portability can be obtained by providing a friction member on the solid writing body or on the exterior of a solid writing implement in which the solid writing body is housed in an exterior container. Specifically, examples include a form in which a friction member is provided on an exterior shaped like a pencil or crayon, made of wood or paper, etc.

[0117] Furthermore, reversible thermochromic colorants such as reversible thermochromic compositions, reversible thermochromic microcapsule pigments or resin particles can be melt-blended with thermoplastic resins, thermosetting resins, waxes, etc. to form pellets, powders, or pastes, and used as reversible thermochromic molding resin compositions. The reversible thermochromic molding resin composition can be subjected to general-purpose injection molding, extrusion molding, blow molding, cast molding, or other methods to obtain molded articles in the form of three-dimensional objects of any shape, films, sheets, plates, filaments, rods, pipes, and the like. Furthermore, by melt-blending it with a thermoplastic resin, toner and powder coatings can be obtained.

[0118] In addition, by blending a non-thermochromic colorant such as a general dye or pigment into the reversibly thermochromic liquid composition, solid molding for coating, or molding resin composition, the reversibly thermochromic liquid composition exhibits a color change behavior from color (1) to color (2).

[0119] A layer containing a light stabilizer and / or a transparent metallic luster pigment can be laminated on the molded body or laminate to improve light resistance, or a top coat layer can be provided to improve durability. Examples of light stabilizers include ultraviolet absorbers, antioxidants, singlet oxygen quenchers, superoxide anion quenchers, and ozone quenchers. Examples of transparent metallic luster pigments include pigments having a core material such as natural mica, synthetic mica, glass flakes, alumina, or transparent film flakes whose surface is coated with a metal oxide such as titanium oxide.

[0120] Specific examples of products using the reversible thermochromic composition and the microcapsule pigment or resin particles containing the same include the following. (1)Toys Dolls and animal-shaped toys, hair for dolls and animal-shaped toys, doll houses and furniture, clothes, doll accessories such as hats, bags, shoes, accessory toys, stuffed toys, drawing toys, toy picture books, puzzle toys such as jigsaw puzzles, building block toys, block toys, clay toys, fluid toys, tops, kites, musical instrument toys, cooking toys, gun toys, catching toys, background toys, toys imitating vehicles, animals, plants, buildings, food, etc. (2) Clothing Clothing such as T-shirts, sweatshirts, blouses, dresses, swimwear, raincoats, skiwear, footwear such as shoes and shoelaces, cloth accessories such as handkerchiefs, towels, wrapping cloths, gloves, ties, hats, scarves, mufflers, etc. (3) Indoor decorations Carpets, curtains, curtain strings, tablecloths, rugs, cushions, carpets, rugs, chair upholstery, seats, mats, picture frames, artificial flowers, photo frames, etc. (4) Furniture Bedding such as futons, pillows, mattresses, lighting equipment, heating and cooling equipment, etc. (5) Ornaments Rings, bracelets, tiaras, earrings, hair clips, false nails, ribbons, scarves, watches, glasses, etc. (6) Stationery Writing implements, stamps, erasers, writing pads, rulers, notebooks, adhesive tape, etc. (7)Daily necessities Lipstick, eye shadow, foundation, eyeliner, eyebrow pencil, nail polish, hair dye, false nails, false nail paint, and other cosmetics, toothbrushes, etc. (8) Kitchen utensils Cups, plates, chopsticks, spoons, forks, pots, frying pans, etc. (9) Other Calendars, labels, cards, recording materials, various types of printed materials for preventing counterfeiting, picture books and other books, bags, packaging containers, embroidery thread, sports equipment, fishing tackle, coasters, musical instruments, hand warmers, ice packs, wallets and other bags, umbrellas, vehicles, buildings, temperature detection indicators, training tools, etc. [Example]

[0121] Examples are shown below, in which "parts" refers to parts by mass. Example 1 Preparation of reversible thermochromic composition A reversible thermochromic composition was obtained by mixing 4 parts of 2-(3-trifluoromethylanilino)-6-(dipentylaminofluoran as component (A), 5 parts of a 1,3-diphenylurea derivative (compound 1-1) as component (B), 25 parts of myristyl alcohol and 25 parts of butyl stearate as component (C), and dissolving the mixture by heating. The composition changed color from black to colorless.

[0122] Example 2 Preparation of reversible thermochromic microencapsulated pigments A reversible thermochromic composition was prepared by mixing 4 parts of 2-(3-trifluoromethylanilino)-6-(dipentylaminofluoran as component (A), 5 parts of a 1,3-diphenylurea derivative (compound 1-2) as component (B), and 50 parts of neopentyl stearate as component (C), and a microcapsule pigment suspension was obtained by interfacial polymerization. The pigment was isolated from the microcapsule pigment suspension by centrifugation to obtain a reversible thermochromic microcapsule pigment having an average particle size of 2 μm, which changes color from black to colorless.

[0123] Example 3 Preparation of reversible thermochromic microencapsulated pigments A reversible thermochromic composition was prepared by mixing 4 parts of 2-(3-trifluoromethylanilino)-6-(dipentylaminofluoran as component (A), 5 parts of a 1,3-diphenylurea derivative (compound 1-4) as component (B), and 50 parts of 4-benzyloxyphenylethyl caprate as component (C), and a microcapsule pigment suspension was obtained by interfacial polymerization. The pigment was isolated from the microcapsule pigment suspension by centrifugation to obtain a reversible thermochromic microcapsule pigment having an average particle size of 2 μm, which changes color from black to colorless.

[0124] Example 4 Preparation of reversible thermochromic microencapsulated pigments A reversible thermochromic composition was prepared by mixing 2 parts of 3',6'-bis[phenyl(3-methylphenyl)amino]-spiro[isobenzofuran-1(3H),9'-[9H]xanthene]-3-one as component (a), 5 parts of 1,3-diphenylurea derivative (compound 2-2) as component (b), and 50 parts of 4-benzyloxyphenylethyl caprate as component (c), and a microcapsule pigment suspension was obtained by interfacial polymerization. The pigment was isolated from the microcapsule pigment suspension by centrifugation to obtain a reversible thermochromic microcapsule pigment having an average particle size of 2 μm, which changes color from blue to colorless.

[0125] Example 5 Preparation of reversible thermochromic microencapsulated pigments A reversible thermochromic composition was prepared by mixing 3 parts of 9-ethyl(3-methylbutyl)amino-spiro[12H-benzo(a)xanthene-12,1'(3'H)isobenzofuran]-3'-one as component (a), 5 parts of 1,3-diphenylurea derivative (compound 2-4) as component (b), and 50 parts of 4-benzyloxyphenylethyl caprate as component (c), and a microcapsule pigment suspension was obtained by interfacial polymerization. The pigment was isolated from the microcapsule pigment suspension by centrifugation to obtain a reversible thermochromic microcapsule pigment having an average particle size of 2 μm and changing color from pink to colorless.

[0126] Preparation of measurement samples The reversible thermochromic composition of Example 1 was filled into a transparent glass capillary tube having an inner diameter of 1 mm and a length of 78 mm to a height of about 10 mm from the bottom of the capillary tube to obtain a measurement sample. The entire portion of the measurement sample containing the reversible thermochromic composition was immersed in a transparent heat medium, and the discoloration state of the reversible thermochromic composition was visually observed while changing the temperature of the transparent heat medium, and t1 (complete color development temperature), t2 (color development initiation temperature), t3 (discoloration initiation temperature), t4 (complete discoloration temperature), and ΔH (hysteresis width: midpoint temperature between t3 and t4 - midpoint temperature between t1 and t2) were determined. Reversible thermochromic inks were prepared by uniformly dispersing 40 parts of the reversible thermochromic microcapsule pigments of Examples 2 to 5 in an aqueous ink vehicle consisting of 50 parts of ethylene-vinyl acetate resin emulsion, 1 part of leveling agent, 1 part of defoaming agent, 0.5 parts of viscosity modifier, and 7.5 parts of water. A solid pattern was screen printed on fine paper using the ink to obtain a measurement sample. The sample was placed in the measuring section of a colorimeter (TC-3600 colorimeter, manufactured by Tokyo Denshoku Co., Ltd.), and the sample was heated and cooled at a rate of 2°C / min. The brightness value was measured as the color density at each temperature, and a color density-temperature curve was created. From the color density-temperature curve, t1 (complete color development temperature), t2 (color development onset temperature), t3 (discoloration onset temperature), t4 (complete discoloration temperature), and ΔH (hysteresis width) were calculated. The test results are shown in Table 1 below.

[0127] [Table 1]

[0128] Application example 1 Making a ballpoint pen A reversible thermochromic ink composition was prepared, consisting of 20 parts of the reversible thermochromic microcapsule pigment prepared in Example 3 (previously cooled to -18°C or below to develop a black color), 0.3 parts of xanthan gum, 10 parts of urea, 10 parts of glycerin, 0.5 parts of a nonionic penetrant, 0.1 parts of a modified silicone antifoaming agent, 0.2 parts of a preservative, and 58.9 parts of water. The reversible thermochromic ink composition was filled into a polypropylene pipe by suction, and the pipe was connected to a ballpoint pen tip having a 0.5 mm stainless steel ball at the tip via a resin holder. Next, a viscoelastic ink backflow prevention material (liquid plug) mainly composed of polybutene was filled into the rear end of the polypropylene pipe, and then a tail plug was fitted to the rear of the pipe.The front and rear barrels were then assembled, and the cap was then fitted.Then, the pen was degassed by centrifugation to obtain a ballpoint pen. In addition, SEBS resin is attached to the rear portion of the rear barrel as a friction body. The ballpoint pen was used to write on the paper to form black letters (handwriting). The handwriting was black at room temperature (25°C), and when the letters were rubbed with a friction material, the letters disappeared and became colorless, and this state could be maintained unless the letters were cooled to -18°C or below. When the paper surface was placed in a freezer and cooled to -18°C or below, the letters again turned black, and this discoloration behavior could be reproduced repeatedly.

[0129] Application example 2 Making a marking pen A reversible thermochromic ink composition was obtained by mixing 25.0 parts of the reversible thermochromic microcapsule pigment prepared in Example 4 (previously cooled to -17°C or below to develop a blue color), 0.5 parts of a comb-type polymer dispersant (manufactured by Lubrizol Japan Co., Ltd., trade name: Solsperse 43000), 1.0 part of an organic nitrogen-sulfur compound (manufactured by Hokko Chemical Industry Co., Ltd., trade name: Hokuside R-150, a mixture of 2-methyl-4-isothiazolin-3-one and 5-chloro-2-methyl-4-isothiazolin-3-one), 0.5 parts of polyvinyl alcohol, 35.0 parts of glycerin, 0.02 parts of an antifoaming agent, and 37.98 parts of water. The ink composition was impregnated into an ink occlusion body made of polyester sliver covered with a synthetic resin film, and the ink was housed in a barrel made of polypropylene resin. A resin-processed pen body (chisel type) made of polyester fiber was assembled to the tip of the barrel in a connected state via a holder, and a cap was attached to obtain a marking pen. The rear end of the barrel is fitted with SEBS resin as a friction member. The marking pen was used to write on the paper to form blue letters (handwriting). The handwriting was blue at room temperature (25°C), and when the letters were rubbed with a friction material, the letters disappeared and became colorless, and this state could be maintained unless the letters were cooled to -17°C or below. When the paper surface was placed in a freezer and cooled to -17°C or below, the letters again turned blue, and this discoloration behavior could be reproduced repeatedly.

[0130] Application example 3 Preparation of solid cursive writing A mixture for the inner core was prepared by kneading 40 parts of the reversible thermochromic microcapsule pigment prepared in Example 4 (previously cooled to -17°C or below to develop a blue color), 35 parts of talc (filler), 10 parts of a side-chain crystalline polyolefin (excipient) [manufactured by Toyokuni Oil Mills, product name: HS Crystal 4100], 10 parts of a polyolefin wax (excipient) [manufactured by Sanyo Chemical Industries, Ltd., product name: Sunwax 131-P (softening point 110°C, penetration 3.5)], 2 parts of a styrene-acrylic acid copolymer resin, 2 parts of a polyvinyl alcohol resin, and 1 part of a hindered amine light stabilizer in a kneader. Next, 69 parts of talc (filler), 10 parts of sucrose fatty acid ester, 10 parts of polyolefin wax (filler), and 10 parts of ethylene-vinyl acetate copolymer were kneaded in a kneader to prepare a kneaded material for the outer shell. The kneaded material for the outer shell was wrapped around the outer peripheral surface of the kneaded material for the inner core so that the kneaded material for the inner core would become the inner core, and compression molding was performed using a press to form a solid writing body with a core-sheath structure, with an outer diameter of φ3 mm and a length of 60 mm (the inner core was φ2 mm and the outer shell thickness was 0.5 mm). Note that the above dimensions are set values, and the solid writing body was manufactured by cooling to -17°C after compression molding and returning to room temperature. The solid writing body was molded into a round outer shaft (wooden shaft) to obtain a pencil. A cylindrical friction body made of SEBS resin was then fixed to the rear end of the pencil via a metal connecting member to produce a solid writing implement with a friction body (a pencil with a friction body). When the solid writing implement was used to write on paper to form blue letters (handwriting), the handwriting was blue at room temperature (25°C). When the letters were rubbed with a friction member, the letters disappeared and became colorless, and this state could be maintained unless the paper was cooled to -17°C or below. Furthermore, when the paper was placed in a freezer and cooled to below -17°C, the letters again turned blue, and this discoloration behavior could be reproduced repeatedly.

[0131] Application example 4 Stamp creation A reversible thermochromic stamp ink was prepared by mixing 20 parts of the reversible thermochromic microcapsule pigment prepared in Example 5 (previously cooled to -18°C or below to develop a pink color), 50 parts of glycerin, 1.5 parts of an alkali-soluble acrylic emulsion (manufactured by Rohm and Haas Japan Co., Ltd., product name: Primal DR73), 0.9 parts of triethanolamine, 10 parts of a 50% aqueous solution of polyvinylpyrrolidone, 0.2 parts of a silicone-based antifoaming agent, 0.5 parts of a penetrating leveling agent, 0.2 parts of a preservative, and 16.7 parts of water. The ink for stamping was impregnated into a stamp material having continuous pores, and the stamp material was fixed to a stamp base material so that the printing surface of the stamp material was exposed, and a cap was fitted to prepare a stamp. The rear end of the stamp base material is fitted with SEBS resin as a friction member. When the stamp was repeatedly pressed against the surface to be stamped (paper), the ink flowed smoothly from the surface of the stamping material and transferred to the surface to be stamped, allowing clear images to be continuously formed without bleeding. The printed image was pink at room temperature (25°C), and when rubbed with a friction member, the printed image disappeared and became colorless, and this state could be maintained unless cooled to -18°C or below. Furthermore, when the paper surface was placed in a freezer and cooled to below -18°C, the print again showed a discoloration behavior, turning pink, and this discoloration behavior could be reproduced repeatedly.

[0132] Application example 5 Preparation of reversible thermochromic printed matter A reversible thermochromic offset ink was prepared by mixing 30 parts of the reversible thermochromic microcapsule pigment prepared in Example 3 (previously cooled to -18°C or below to develop a black color), 5 parts of a red dye, and 65 parts of a linseed oil-based offset ink vehicle. The offset ink was used for offset printing on both the front and back sides of wood-free paper as a printing medium, and the ink was dried and hardened to form a date (thermochromic image). The thermochromic images on the front and back surfaces are formed so as not to overlap each other. Next, offset printing was carried out using a non-discoloring black offset ink, which was then dried and hardened to form a frame line (non-discoloring image), thereby producing a reversibly thermochromic printed matter. The reversible thermochromic printed matter is initially a notebook-style printed matter with black dates printed on it, but by rubbing the thermochromic image at any point on the surface with a friction member, the frictional heat generated can cause the color to change to red, and the discolored state can be maintained at room temperature (25°C), making it useful for managing holiday schedules. Furthermore, the date written on the back of the discolored area does not discolor due to heat being transferred when the thermochromic image on the front is discolored, allowing for accurate schedule management.

[0133] Application example 6 Preparation of reversible thermochromic indicator A reversible thermochromic layer was formed on the surface of a white polyester film (thickness 25 μm) used as a support by printing the reversible thermochromic microcapsule pigment prepared in Example 3 on the surface using an ink dispersed in a vehicle containing a binder resin, and then a transparent polyester film 16 μm thick was laminated on top of the layer to obtain a reversible thermochromic display. The display was once cooled to -18°C or below to allow the reversible thermochromic layer to completely develop a black color, and then printed with a thermal transfer printer to form white outline characters. The white outline characters are visible as long as the display body is maintained in a temperature range of -18°C to 64°C. Furthermore, when the display body was cooled again to below -18°C and the reversible thermochromic layer was completely colored black, the white cut-out letters became invisible, and by forming white cut-out letters using the thermal transfer printer, the display body could be used repeatedly.

[0134] Application example 7 Making dolls Five parts of the reversible thermochromic microcapsule pigment prepared in Example 2, one part of dispersant, 94 parts of nylon 12 with a melting point of 180°C, and 0.1 parts of a pink general pigment were melt-mixed in an extruder at 200°C to prepare reversible thermochromic pellets for the core. The reversibly thermochromic pellets were fed into an extruder for forming the core, and the nylon 12 natural pellets were fed into an extruder for forming the sheath. Using a composite fiber spinning device, the fibers were spun at 200°C through 18 nozzles so that the core:sheath volume ratio was 6:4, to prepare a reversibly thermochromic composite fiber consisting of 18 single fibers with an outer diameter of 90 μm. Furthermore, the reversible thermochromic composite fiber was implanted in the head of a doll in a conventional manner to produce a doll with hair made of the reversible thermochromic composite fiber. The doll's hair was cooled to below 12°C, allowing it to turn completely black. When it was then immersed in hot water at 40°C, it changed from black to pink. When it was removed from the hot water and immersed in cold water at 5°C, it turned black again. This change could be repeated.

[0135] Application example 8 Preparation of a reversible thermochromic miniature car A reversible thermochromic spray paint was obtained by stirring and mixing 15 parts of the reversible thermochromic microcapsule pigment prepared in Example 2 into a vehicle consisting of 40 parts of a 50% acrylic resin / xylene solution, 20 parts of xylene, 20 parts of methyl isobutyl ketone, and 5 parts of a polyisocyanate-based curing agent. The reversible thermochromic spray paint was sprayed onto the entire body of a white miniature car and dried to form a reversible thermochromic layer, thereby obtaining a reversible thermochromic miniature car (toy). The miniature car was once cooled to below 12°C, and the reversible thermochromic layer completely turned black. When the car was then immersed in warm water at 40°C, it turned white. When the car was removed from the warm water and immersed in cold water at 5°C, it turned black again, and this process could be repeated.

[0136] Application example 9 Fabrication of a mug with reversible thermochromic properties A reversible thermochromic epoxy ink was obtained by mixing 30 parts of the reversible thermochromic microcapsule pigment prepared in Example 2, 60 parts of a hard liquid epoxy resin, 2 parts of an ultraviolet absorber, 2 parts of a thixotropic agent, and 0.5 parts of an antifoaming agent, and then adding 40 parts of a room temperature curing aliphatic polyamine. Using the reversible thermochromic epoxy ink, a polka dot pattern was printed on the side of a ceramic mug using a curved printing machine with a stainless steel screen plate, and the ink was then heated and cured at 70°C for 1 hour to form a reversible thermochromic layer, thereby obtaining a reversible thermochromic mug. When cold water below 12°C is poured into the mug, the reversible thermochromic layer turns black and the polka dots become visible, but when the cold water is removed and hot water at 50°C is poured, the reversible thermochromic layer disappears and becomes colorless.When the hot water is removed and cold water at 5°C is poured, the reversible thermochromic layer turns color and the black polka dots become visible again. This change in appearance could be repeated by changing the temperature. [Explanation of symbols]

[0137] t1 Full color temperature t2 Color development start temperature t3 Discoloration start temperature t4 Complete color erasure temperature ΔH Hysteresis width

Claims

1. A reversible thermochromic composition comprising: (a) an electron-donating organic color-forming compound; (b) a compound represented by formula (1) or (2) as an electron-accepting compound; and (c) a reaction medium that reversibly induces an electron-donating / accepting reaction between the components (a) and (b) in a specific temperature range. 【Chemistry 1】 【Chemistry 2】 (In formulas (1) and (2), R １ represents a halogen atom or a linear or branched alkoxy group having 1 to 8 carbon atoms. ２ represents a substituted or unsubstituted linear or branched alkyl group having 1 to 18 carbon atoms.

2. In formulas (1) and (2), R １ is a halogen atom, and R ２ 2. The reversible thermochromic composition according to claim 1, wherein is a substituted or unsubstituted straight-chain or branched-chain alkyl group having 4 to 8 carbon atoms.

3. A reversible thermochromic microcapsule pigment encapsulating the reversible thermochromic composition according to claim 1 or 2.

4. A reversible thermochromic liquid composition comprising the reversible thermochromic microcapsule pigment according to claim 3 and a vehicle.

5. The reversible thermochromic liquid composition according to claim 4, which is selected from the group consisting of printing ink, writing ink, applicator ink, stamp ink, inkjet ink, paint, ultraviolet-curable ink, coloring material, cosmetics, and textile coloring liquid.

6. A reversible thermochromic solid molding for coating, comprising the reversible thermochromic microcapsule pigment according to claim 3 and an excipient.

7. 7. The reversibly thermochromic solid molding for application according to claim 6, which is a solid writing material or a solid cosmetic.

8. A reversible thermochromic molding resin composition comprising the reversible thermochromic microcapsule pigment according to claim 3 and a molding resin.

9. A reversibly thermochromic molded article obtained by molding the reversibly thermochromic molding resin composition according to claim 8.

10. A reversible thermochromic laminate comprising a support and a reversible thermochromic layer comprising the reversible thermochromic microencapsulated pigment according to claim 3.

11. A writing instrument containing the writing instrument ink according to claim 5.

12. 12. The writing implement according to claim 11, further comprising a friction member that discolors handwriting made with the writing implement by frictional heat.

Images