Water-changeable materials and water-changeable indicators, colorants

Abstract

This invention provides a water-color-changing material, a water-color-changing indicator, and a colorant that develop color upon contact with water, exhibiting a deep color when colored, showing good color development even with a small amount of water, and maintaining its color over time. [Solution] A water-color-changing material, a water-color-changing indicator, and a colorant comprising a porous material containing a water-color-changing composition comprising an electron-donating chromogenic organic compound, an electron-accepting compound, and an amide compound and / or an imidazolidinone compound. Furthermore, the amide compound may be an amide compound of a specific structure, and the imidazolidinone compound may be an imidazolidinone compound of a specific structure.

Description

Technical Field

[0001] The present disclosure relates to a water-discoloring material, a water-discoloring indicator, and a colorant.

Background Art

[0002] Conventionally, water-discoloring colorants that develop color upon wetting with water have been widely known. For example, Patent Document 1 discloses a colorant comprising a composition consisting of an electron-donating chromogenic organic compound, an electron-accepting compound, and polyethylene glycol or tripropylene glycol as a color tone adjuster, which is held or supported on a porous substance and develops color upon contact with water (see, for example, Patent Document 1).

[0003] However, the colorant described in Patent Document 1 has low solubility in polyethylene glycol and tripropylene glycol with respect to the electron-donating chromogenic organic compound and the electron-accepting compound, and furthermore, has low contactability with water. As a result, sufficient good color development may not be obtained upon contact with moisture, the color may fade over time, or it may not develop color with a small amount of moisture.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] [[ID=z38]] The present disclosure solves the conventional problems and provides a water-discoloring material that develops color upon contact with moisture, has a deep color during color development, exhibits good color development even with a small amount of moisture, and can maintain the color development even after a lapse of time.

Means for Solving the Problems

[0006] [1] A water-color-changing material comprising a water-color-changing composition containing an electron-donating color-changing organic compound, an electron-accepting compound, and an amide compound and / or an imidazolidinone compound, in a porous material.

[0007] [2] The water-color-changing material according to [1], wherein the amide compound is an amide compound represented by general formula (1). [ka] [In general formula (1), R1 and R2 are each independently organic groups having 1 to 30 carbon atoms, and R3 is one of an alkoxyalkyl group, an alkyl group, an alkenyl group, or a hydrogen atom.]

[0008] [3] The water-color-changing material according to [1] or [2], wherein the imidazolidinone compound is an imidazolidinone compound represented by general formula (2). [ka] [In general formula (2), R4 and R5 are each independently organic groups having 1 to 20 carbon atoms.]

[0009] [4] The water-color-changing material according to any one of [1] to [3], wherein the porous material is an inorganic porous material.

[0010] [5] The porous material is a porous material having silanol groups, as described in any of [1] to [4].

[0011] [6] A water-color-changing indicator comprising a water-color-changing material as described in any of [1] to [5].

[0012] [7] A coloring agent comprising a water-color-changing material as described in any of [1] to [5]. [Effects of the Invention]

[0013] According to the present disclosure, it is possible to provide a water-discoloring material that develops color upon contact with water, has a deep color when developing color, develops color well even with a small amount of moisture, and can maintain the color development over time.

Embodiments for Carrying Out the Invention

[0014] Specific embodiments of the present disclosure will be described in detail below. Note that it is not limited to the embodiments described below.

[0015] In this specification, "parts", "%", "ratio", etc. are based on mass unless otherwise specified.

[0016] In this specification, the state of "comprising a water-discoloring composition in a porous material" may be a state in which the water-discoloring composition is immobilized in the porous material by adsorption or adhesion, or a state in which the water-discoloring composition is contained without being immobilized in the porous material.

[0017] The water-discoloring material of the present disclosure is characterized by comprising a water-discoloring composition containing an electron-donating color-forming organic compound, an electron-accepting compound, and an amide compound and / or an imidazolidinone compound in a porous material.

[0018] <Water-discoloring composition> The water-discoloring composition of the present disclosure is characterized by comprising at least an electron-donating color-forming organic compound, an electron-accepting compound, and an amide compound and / or an imidazolidinone compound.

[0019] Generally, an electron-donating color-forming organic compound and an electron-accepting compound can undergo a color-forming reaction by donating and accepting electrons between them. However, when an amide compound or an imidazolidinone compound is present here, the donation and acceptance of electrons between the electron-donating color-forming organic compound and the electron-accepting compound are inhibited, and no color-forming reaction is shown. When moisture contacts the water-discoloring material, the amide compound or imidazolidinone compound in the water-discoloring material migrates to the moisture side and the water-discoloring material develops color. When a water-color-changing material is in a colored state, the water-color-changing material loses its color once the water evaporates or otherwise disappears from the material. This is because the amide compounds and imidazolidinone compounds then inhibit the transfer of electrons between the electron-donating organic compound and the electron-accepting compound.

[0020] The state of the water-color-changing composition is not particularly limited as long as it can be incorporated into a porous material, and it may be a liquid, a gas, or a solid at room temperature (25°C). If it is a gas, it is preferable to incorporate it into a porous material in a liquid state under low temperature conditions or by cooling. If the material is solid, it is preferable to incorporate it into a porous material in a liquid state by heating or under high-temperature conditions.

[0021] <Electron-donating color-forming organic compound> Electron-donating chromogenic organic compounds are compounds that determine color by donating electrons to electron-accepting compounds that function as color developers, thereby producing color.

[0022] Examples of electron-donating colorimetric organic compounds include phthalide compounds, fluorane compounds, styrinoquinoline compounds, diazalodamine lactone compounds, pyridine compounds, quinazoline compounds, and bisquinazoline compounds. Examples of phthalide compounds include diphenylmethane phthalide compounds, phenylindolyl phthalide compounds, indolyl phthalide compounds, diphenylmethane azaphthalide compounds, phenylindolyl azaphthalide compounds, and their derivatives. Examples of fluorane compounds include aminofluorane compounds, alkoxyfluorane compounds, and their derivatives.

[0023] The following are examples of compounds that can be used as electron-donating, chromogenic organic compounds. 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophthalide, 3-(4-diethylaminophenyl)-3-(1-ethyl-2-methylindole-3-yl)phthalide, 3,3-Bis(1-n-butyl-2-methylindole-3-yl)phthalide, 3,3-Bis(2-ethoxy-4-diethylaminophenyl)-4-azaphthalide, 3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindole-3-yl)-4-azaphthalide, 3-(2-n-hexyloxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindole-3-yl)-4-azaphthalide, 3-[2-ethoxy-4-(N-ethylanilino)phenyl]-3-(1-ethyl-2-methylindole-3-yl)-4-azaphthalide, 3-(2-acetamido-4-diethylaminophenyl)-3-(1-propyl-2-methylindole-3-yl)-4-azaphthalide, 3,6-Bis(diphenylamino)fluorane, 3,6-Bis(N-phenyl-Np-tolylamino)fluorane, 3,6-Dimethoxyfluorane, 3,6-di-n-butoxyfluorane, 2-methyl-6-(N-ethyl-Np-tolylamino)fluorane, 3-Chloro-6-cyclohexylaminofluorane, 2-methyl-6-cyclohexylaminofluorane, 2-chloroamino-6-di-n-butylaminofluorane, 2-(2-chloroanilino)-6-di-n-butylaminofluorane, 2-(3-trifluoromethylanilino)-6-diethylaminofluorane, 2-(3-trifluoromethylanilino)-6-di-n-pentylaminofluorane, 2-Dibenzylamino-6-diethylaminofluorane, 2-N-methylanilino-6-(N-ethyl-Np-tolylamino)fluorane, 1,3-dimethyl-6-diethylaminofluorane, 2-Chloro-3-methyl-6-diethylaminofluorane, 2-anilino-3-methyl-6-diethylaminofluorane, 2-anilino-3-methoxy-6-diethylaminofluorane, 2-anilino-3-methyl-6-di-n-butylaminofluorane, 2-anilino-3-methoxy-6-di-n-butylaminofluorane, 2-Xylidino-3-methyl-6-diethylaminofluorane, 2-anilino-3-methyl-6-(N-ethyl-Np-tolylamino)fluorane, 6-Diethylamino-1,2-benzofluorane, 6-(N-ethyl-N-isobutylamino)-1,2-benzofluorane, 6-(N-ethyl-N-isopentylamino)-1,2-benzofluorane, 2-(3-methoxy-4-dodecoxystyryl)quinoline, 2-Diethylamino-8-diethylamino-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidine-5,1′(3′H)-isobenzofuran]-3′-one, 2-di-n-butylamino-8-di-n-butylamino-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidine-5,1′(3′H)-isobenzofuran]-3′-one, 2-di-n-butylamino-8-diethylamino-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidine-5,1′(3′H)-isobenzofuran]-3′-one, 2-di-n-butylamino-8-(N-ethyl-N-isoamylamino)-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidine-5,1′(3′H)-isobenzofuran]-3′-one, 2-di-n-butylamino-8-di-n-pentylamino-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidine-5,1′(3′H)-isobenzofuran]-3′-one, 4,5,6,7-Tetrachloro-3-(4-dimethylamino-2-methoxyphenyl)-3-(1-n-butyl-2-methylindole-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-Tetrachloro-3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindole-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-Tetrachloro-3-(4-diethylamino-2-ethoxyphenyl)-3-(1-n-pentyl-2-methylindole-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-Tetrachloro-3-(4-diethylamino-2-methylphenyl)-3-(1-ethyl-2-methylindole-3-yl)-1(3H)-isobenzofuranone, 3′,6′-bis[phenyl(2-methylphenyl)amino]spiro[isobenzofuran-1(3H),9′-[9H]xanthene]-3-one, 3′,6′-bis[phenyl(3-methylphenyl)amino]spiro[isobenzofuran-1(3H),9′-[9H]xanthene]-3-one, 3′,6′-bis[phenyl(3-ethylphenyl)amino]spiro[isobenzofuran-1(3H),9′-[9H]xanthene]-3-one, 2,6-bis(2′-ethyloxyphenyl)-4-(4′-dimethylaminophenyl)pyridine, 2,6-Bis(2′,4′-diethyloxyphenyl)-4-(4′-dimethylaminophenyl)pyridine, 2,6-bis(2,4-diethyloxyphenyl)-4-[4-bis(4-methyloxyphenyl)aminophenyl]pyridine, 2-(4′-dimethylaminophenyl)-4-methoxyquinazoline, 4,4′-Ethylenedioxy-bis[2-(4-diethylaminophenyl)quinazoline]

[0024] Furthermore, fluoranes may include not only compounds having substituents on the phenyl group forming the xanthene ring, but also compounds that exhibit a blue or black color, having substituents on the phenyl group forming the xanthene ring and also on the phenyl group forming the lactone ring (for example, alkyl groups such as methyl groups, halogen atoms such as chlorine atoms).

[0025] The content of the electron-donating color-changing organic compound is preferably 0.1% by mass or more and 25% by mass or less, and more preferably 0.5% by mass or more and 15% by mass or less, based on the total amount of the water-color-changing composition.

[0026] <Electron-accepting compounds> Electron-accepting compounds are compounds that accept electrons from electron-donating chromogenic organic compounds and function as color developers for those compounds. As electron-accepting compounds, conventionally known compounds can be used, and examples include compounds selected from the group of compounds having active protons, the group of pseudoacidic compounds (compounds that are not acids but act as acids in water-color-changing compositions to cause electron-donating color-developing organic compounds to develop color), and the group of compounds having electron vacancies.

[0027] Examples of compounds having active protons include compounds having a phenolic hydroxyl group and their derivatives, carboxylic acids and their derivatives, acidic phosphate esters and their derivatives, azole compounds and their derivatives, 1,2,3-triazoles and their derivatives, cyclic carbosulfoimides, C2-C5 halohydrins, sulfonic acids and their derivatives, and inorganic acids. As for carboxylic acids and their derivatives, aromatic carboxylic acids and their derivatives, or C2-C5 aliphatic carboxylic acids and their derivatives are preferred. Examples of pseudoacidic 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 containing electron vacancies include borates, borate esters, and inorganic salts.

[0028] The following are examples of compounds that can be used as electron-accepting compounds. Phenol, o-cresol, 4-np-nonylphenol, 4-n-octylphenol, 4-n-dodecylphenol, 4-n-stearylphenol, 4-chlorophenol, 4-bromophenol, 2-phenylphenol, 4-hydroxybenzoate n-butyl, 4-hydroxybenzoate n-octyl, resorcinol, 4-tert-butylcatechol, 2,4-dihydroxy-4′-tert-butylbenzophenone, dodecyl gallate, 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-hydroxyphenyl)n-dodecane, 1,1-bis(4-hydroxyphenyl)-2-methylpropane, 1,1-bis(4-hydroxyphenyl) Phenyl)-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-phenyl-1,1-bis(4-hydroxyphenyl) 2,2-bis(4-hydroxyphenyl)ethane, 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)ethylpropionate, 2,2-Bis(4-hydroxyphenyl)-4-methylpentane, 2,2-Bis(4-hydroxyphenyl)-4-methylhexane, 2,2-Bis(4-hydroxyphenyl)hexafluoropropane, 2,2-Bis(4-hydroxy-3-methylphenyl)propane, 2,2-Bis(4-hydroxy-3-methylphenyl)butane, 9,9-Bis(4-hydroxy-3-methylphenyl)fluorene, 1,3-Bis[2-(4-hydroxyphenyl)-2-propyl]benzene, Bis(2-hydroxyphenyl)methane, 4,4′-Dihydroxydiphenylsulfone, 4-Isopropoxy-4′-Hydroxydiphenylsulfone, Bis(4-hydroxyphenyl)sulfide, 1,1,1-Tris(4-hydroxyphenyl)ethane, 4,4′-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl ]phenyl}ethylidene]bisphenol, 4,4′-[4-(4-hydroxyphenyl)-sec-butylidene]bis(2-methylphenol), N-(2-fluorophenyl)-N′-phenylurea, N-(2-chlorophenyl)-N′-phenylurea, N-(2-methoxyphenyl)-N′-phenylurea, N-[3-[[(4-tert-butylphenyl)sulfonyl]oxy]phenyl]-N′-phenylurea, N-[3-[[(4-methylphenyl)sulfonyl]oxy]phenyl]-N′-phenylurea, N-[3-[[(4-methyloxyphenyl)sulfonyl]oxy]phenyl]-N′-phenylurea, N-[3-[[(4-chlorophenyl)sulfonyl]oxy]phenyl]-N′-phenylurea, 4-methyl-N-[[[3-[[(4-methylphenyl)sulfonyl]oxy]phenyl]amino]carbonyl]benzenesulfonamide,

[0029] The content of the electron-accepting compound is preferably 0.01% by mass or more and 30% by mass or less, and more preferably 1% by mass or more and 25% by mass or less, based on the total amount of the water-color-changing composition.

[0030] <Amide compounds and imidazolidinone compounds> The water-color-changing composition disclosed herein contains an amide compound and / or an imidazolidinone compound, which allows the water-color-changing composition to penetrate more easily into the porous material, and furthermore, even when the amount of the water-color-changing composition in the porous material is small, a water-color-changing material that develops color upon contact with moisture can be obtained.

[0031] Among amide compounds and imidazolidinone compounds, it is preferable to include at least one of the amide compound represented by general formula (1) and the imidazolidinone compound represented by general formula (2) in order to obtain a highly hydrophilic, water-color-changing composition that develops a deep color immediately after contact with water.

[0032] [ka]

[0033] In general formula (1), R1 and R2 are each independently organic groups having 1 to 30 carbon atoms, and R3 is either an alkoxyalkyl group, an alkyl group, an alkenyl group, or a hydrogen atom.

[0034] [ka]

[0035] In general formula (2), R4 and R5 are each independently organic groups having 1 to 20 carbon atoms.

[0036] Due to their amide structure, amide compounds of general formula (1) and imidazolidinone compounds of general formula (2) exhibit high solubility in electron-donating chromogenic organic compounds and electron-accepting compounds with respect to amide compounds of general formula (1) and imidazolidinone compounds of general formula (2). Furthermore, amide compounds of general formula (1) and imidazolidinone compounds of general formula (2) further inhibit the transfer of electrons between electron-donating chromogenic organic compounds and electron-accepting compounds, resulting in the absence of a color reaction.

[0037] Furthermore, because the amide compounds of general formula (1) and the imidazolidinone compounds of general formula (2) have an amide structure, the amide compounds of general formula (1) and the imidazolidinone compounds of general formula (2) exhibit high solubility in water. Therefore, upon contact with moisture, the amide compound of general formula (1) and the imidazolidinone compound of general formula (2) migrate to the moisture, and electrons are transferred between the electron-donating chromogenic organic compound and the electron-accepting compound, resulting in a good color development effect through a color reaction. Furthermore, because the water-color-changing composition has low viscosity, it exhibits excellent water transfer properties for amide compounds of general formula (1) and imidazolidinone compounds of general formula (2), making it easy for them to develop color immediately upon contact with water.

[0038] Because both R1 and R2 in general formula (1) are organic groups, it is easy to produce a deep color upon contact with water in a water-color-changing composition without reducing the reactivity and interaction of the electron-donating color-developing organic compound and the electron-accepting compound.

[0039] Examples of these organic groups include hydrocarbon groups and their derivatives. Examples of hydrocarbon groups include aliphatic hydrocarbon groups, alicyclic hydrocarbon groups, and aromatic hydrocarbon groups. The hydrocarbon groups may be linear or branched, and may be saturated or unsaturated. Derivatives of hydrocarbon groups refer to groups that have at least one nitrogen atom, oxygen atom, sulfur atom, sulfonyl group, carbonyl group, etc., at the terminal or molecular level of the hydrocarbon group. Examples include dimethylaminopropyl group, hydroxyethyl group, and dimethyloxobutyl group. Furthermore, R1 and R2 may form a heterocycle with respect to each other, for example, the morpholine skeleton and its derivatives. Of these organic groups, aliphatic hydrocarbon groups are preferred, and alkyl groups are more preferred, considering the long-term stability and deep color development of the water-color-changing composition.

[0040] The alkyl groups R1 and R2 may be linear or branched. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, and butyl groups. From the viewpoint of amphiphilicity with water and electron-donating chromogenic organic compounds and electron-accepting compounds, the alkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, even more preferably methyl or ethyl, and particularly preferably methyl.

[0041] R3 in general formula (1) is selected from an alkoxyalkyl group, an alkyl group, an alkenyl group, or a hydrogen atom. The alkoxyalkyl group, alkyl group, and alkenyl group are not particularly limited in terms of the number of carbon atoms and may be linear or branched. Considering high solubility in water, the alkoxyalkyl group preferably has 2 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 2 to 5 carbon atoms. The alkyl group preferably has 1 to 8 carbon atoms, and more preferably 1 to 6 carbon atoms. The alkenyl group preferably has 2 to 8 carbon atoms, more preferably 2 to 4 carbon atoms, and even more preferably a vinyl group.

[0042] The amide compound of general formula (1) may be synthesized as appropriate, or a commercially available product may be used. Specifically, examples include alkoxyalkylamides, acrylamides, alkylamides, alkenylamides, and formamides. These amide compounds may be used individually or in combination of two or more.

[0043] Among the amide compounds of general formula (1), dimethylamide compounds in which both R1 and R2 are methyl groups are preferred because they develop color immediately upon contact with moisture, have a deep color, and exhibit excellent color development. Examples of dimethylamide compounds include 3-methoxy-N,N-dimethylpropionamide, 3-ethoxy-N,N-dimethylpropionamide, 3-n-butoxy-N,N-dimethylpropionamide, 3-n-propoxy-N,N-dimethylpropionamide, 3-iso-propoxy-N,N-dimethylpropionamide, 3-tert-butoxy-N,N-dimethylpropionamide, and N,N-dimethylacrylamide.

[0044] Since both R4 and R5 in general formula (2) are organic groups, it becomes easy to produce a deep color upon contact with water in a water-color-changing composition without reducing the reactivity and interaction of the electron-donating color-developing organic compound and the electron-accepting compound.

[0045] Examples of imidazolidinone compounds of general formula (2) include 1,3-dimethyl-2-imidazolidinone, 1,3-diethyl-2-imidazolidinone, 1,3-dipropyl-2-imidazolidinone, 1,3-diisopropyl-2-imidazolidinone, 1,3-dibutyl-2-imidazolidinone, and their derivatives. 1,3-dimethyl-2-imidazolidinone is preferred because it yields a deeper color.

[0046] <Other additives> The water-color-changing compositions disclosed herein may further contain various additives in addition to the components of electron-donating color-producing organic compounds, electron-accepting compounds, amide compounds, and imidazolidinone compounds. Specifically, these include UV absorbers, antioxidants, preservatives, and rust inhibitors.

[0047] <Porous material> By incorporating a water-color-changing composition into a porous material, the porous material can retain moisture even with a small amount of water, making it easier to develop color and achieve a deeper color than when the water-color-changing composition is applied directly to the substrate.

[0048] The porous material is not particularly limited as long as it is a porous material that can contain the water-color-changing composition disclosed herein, and may be in any shape such as block, sheet, plate, lump, granule, particle, powder, fine powder, or ultrafine powder, or it may be a porous material that is a combination of these shapes.

[0049] The porous material may be an inorganic porous material, an organic porous material, or a composite material thereof, but an inorganic porous material is preferred because it is poorly soluble in amide compounds and imidazolidinone compounds, and can be uniformly incorporated while maintaining the properties of the porous material.

[0050] Porous materials preferably have pores. The pores in the porous material may be ultra-micropores, super-micropores, micropores, mesopores, or macropores. These pores are preferably open because they can contain water-color-changing compositions and allow moisture to penetrate from the outside. However, the porous material may also have closed pores inside the open pores. Furthermore, while there are no particular limitations on the average pore diameter of the porous material, it is preferably between 1 nm and 10,000 nm. By having an average pore diameter within the above range, the water-color-changing composition is less likely to leak out of the porous material, while the permeability of moisture from the outside can be improved. The average pore diameter can be calculated from the results of pore diameter distribution measurements using the mercury intrusion method.

[0051] The specific surface area of ​​porous materials is not particularly limited, but 10 m² 2 / g or more 1000m 2 Preferably less than / g, 50m 2 / g or more 750m 2 It is preferable that the value be less than or equal to / g. Having a specific surface area within the above range makes it easier to retain moisture from the outside inside the porous material. The specific surface area can be measured by the nitrogen gas adsorption method.

[0052] The oil absorption capacity of the porous material is preferably 10 mL / 100g or more and 2000 mL / 100g or less, more preferably 50 mL / 100g or more and 1500 mL / 100g or less, and even more preferably 100 mL / 100g or more and 1000 mL / 100g or less. Because the oil absorption amount is within the above range, the water-discolorable composition is less likely to leak out of the porous material after a long period of time. The amount of oil absorbed can be measured in accordance with JIS-K5101.

[0053] Examples of porous materials include, specifically, inorganic porous materials such as silica, silica gel, silica alumina, zeolite, montmorillonite, kaolinite, diatomaceous earth, alumina, ceria, titania, zirconia, magnesia, activated carbon, carbon, ceramics, strontium titanate, tin oxide, zirconium dioxide, zinc dioxide, acid clay, activated clay, attapulgite, bentonite, aluminum silicate, magnesium silicate, zinc silicate, tin silicate, calcined kaolin, and talc; porous thermoplastic resin particles such as porous polystyrene particles, porous polyacrylic particles, porous polymethacrylic particles, porous polyester particles, porous amide particles, and porous olefin particles; and porous thermosetting resin particles such as porous polyurethane particles and porous silicone-based resin particles. Furthermore, the porous material may be white or colored.

[0054] Among porous materials, porous materials containing silanol groups may be used because they have high moisture adsorption properties and can easily maintain their colored state. The silanol groups may be isolated silanol groups, vicinal silanol groups, or geminal silanol groups. Porous materials containing silanol groups include silica, silica-alumina, and silica gel.

[0055] The content of the water-color-changing composition relative to the porous material is not particularly limited, but the ratio to the porous material is preferably 0.05 to 2.0, more preferably 0.1 to 1.8, and even more preferably 0.5 to 1.5. If the value is above the lower limit, good color development is easily achieved; if it is below the upper limit, the properties of the porous material are easily maintained; and if the porous material is in the form of particles, it is easily maintained as a powder.

[0056] The water-color-changing material disclosed herein may be configured such that the water-color-changing composition is contained within a porous material and covers all or part of the surface of the porous material.

[0057] <Water-change color indicator> The water-color-changing material disclosed herein can be used as an indicator. Water-color-changing materials may be used as indicators on their own, or they may be used as indicators in combination with materials or substances that do not impair water-color-changing properties.

[0058] Examples of how a water-color-changing material can be used as an indicator include a laminate in which the water-color-changing material is provided alone on a substrate such as a film or paper; an arrangement in which the water-color-changing material and a porous material that does not contain a water-color-changing composition are provided adjacent to each other on a substrate; an arrangement in which the water-color-changing material is embedded in the gaps of a substrate such as cloth or paper; and an arrangement in which a composition in which the water-color-changing material is dispersed in an organic solvent is coated onto a substrate. The base material may be colored with general dyes or pigments.

[0059] As for the organic solvent used to disperse the water-color-changing material, there are no particular restrictions as long as it does not develop color in the solvent; conventionally general-purpose organic solvents can be used. Examples include alcohol-based organic solvents, glycol-based organic solvents, glycol ether-based organic solvents, hydrocarbon-based organic solvents, ketone-based organic solvents, and ester-based organic solvents. Examples of alcohol-based organic solvents include ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, tert-amyl alcohol, and benzyl alcohol. Examples of glycol-based organic solvents include ethylene glycol, diethylene glycol, propylene glycol, and benzyl glycol. Examples of glycol ether-based organic solvents include ethylene glycol monomethyl ether, ethylene glycol diethyl ether, ethylene glycol monoisopropyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether. Examples of hydrocarbon-based organic solvents include n-heptane, n-octane, isooctane, methylcyclohexane, ethylcyclohexane, toluene, xylene, ethylbenzene, and naphthalene. Examples of ketone-based organic solvents include methyl isobutyl ketone, methyl n-propyl ketone, methyl n-butyl ketone, and di-n-propyl ketone. Examples of ester-based organic solvents include n-butyl formate, isobutyl formate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, ethyl propionate, n-butyl propionate, methyl butyrate, and ethyl butyrate. These organic solvents may be used individually or in combination of two or more.

[0060] Furthermore, depending on the type of substrate (e.g., water permeability, water absorption, etc.) and the amount of water in contact with the water-color-changing material, the water-color-changing material can be selected to exhibit reversible or irreversible color changes.

[0061] For example, when using a permeable substrate such as paper or cloth, when moisture comes into contact with the water-color-changing material, amide compounds and imidazolidinone compounds in the water-color-changing material migrate to the moisture, causing the water-color-changing material to develop color. When moisture containing amide compounds and imidazolidinone compounds penetrates the substrate, the amide compounds and imidazolidinone compounds that inhibit electron transfer between electron-donating organic compounds and electron-accepting compounds in the water-color-changing material leach out of the water-color-changing material, thus maintaining the colored state. In other words, it exhibits irreversible color development. On the other hand, if the substrate has low water absorption or if the amount of water in contact with the water-color-changing material is small, the water containing the amide compounds and imidazolidinone compounds will not penetrate the substrate, and the amide compounds and imidazolidinone compounds will remain in the water-color-changing material. When the water disappears from the water-color-changing material due to evaporation or other reasons, the amide compounds and imidazolidinone compounds will again inhibit the transfer of electrons between the electron-donating chromogenic organic compound and the electron-accepting compound, causing the water-color-changing material to lose its color. In other words, it exhibits a reversible change.

[0062] When using an impermeable substrate such as a film or metal, if moisture comes into contact with the water-color-changing material, the amide compounds and imidazolidinone compounds in the water-color-changing material migrate to the moisture, causing the water-color-changing material to change color. However, the moisture containing the amide compounds and imidazolidinone compounds does not penetrate the substrate and remains in the water-color-changing material. When the moisture evaporates or otherwise disappears from the water-color-changing material, the amide compounds and imidazolidinone compounds again inhibit the transfer of electrons between the electron-donating chromogenic organic compound and the electron-accepting compound, causing the water-color-changing material to lose its color. In other words, it exhibits a reversible change.

[0063] The indicators of this disclosure can be used to detect liquids, including water. Specific applications of the indicator include detecting water leaks in pipes, tanks, etc., detecting water damage to circuit boards and wiring in electronic equipment, detecting moisture in storage locations and during transportation of water-reactive substances, detecting moisture in household items such as furniture, detecting condensation history, detecting urine in disposable diapers, detecting moisture during the construction of infrastructure such as bridges and dams, checking the waterproofing of the interior of automobiles, detecting water damage history in cardboard boxes, and detecting water damage to the contents of packaging.

[0064] The indicator can be made to adhere easily to an object by providing an adhesive layer at the bottom, separate from the color-developing layer containing a water-color-changing composition. The adhesive layer is formed from adhesives mainly composed of general-purpose acrylic resins, urethane resins, styrene-butadiene copolymers, vinyl ether copolymers, natural rubber, etc. Furthermore, the adhesive layer may be provided with a release layer, such as release paper, to improve convenience during use.

[0065] The indicator can be cut to the desired size and shape and attached to an object, or it can be rolled onto a core made of paper or the like to form a tape for practical use. The tape form offers excellent portability, eliminates the need for a release layer, promotes resource conservation, and allows for cutting to the appropriate size according to the length of the object, thus satisfying applicability to various shapes and sizes of objects.

[0066] <Coloring agent> The water-color-changing materials disclosed herein are used as colorants, either alone or in combination with materials or substances that do not impair water-color-changing properties.

[0067] The colorants disclosed herein may be used in plastics, cosmetics, films, glass, ceramics, powder coatings, liquid coatings, lacquers, printing ink compositions, writing instrument ink compositions, and the like. Of these, it is preferable to use them in printing ink compositions and writing instrument ink compositions because they readily produce a color change upon contact with moisture.

[0068] The colorants disclosed herein may be used in combination with conventional dyes or pigments, and may be of a different color from the colorants disclosed herein, or they may be of the same color as long as it is recognizable that they develop color upon contact with moisture.

[0069] When applied to printing ink compositions or writing instrument ink compositions, it is preferable to use organic solvents because color development occurs upon contact with moisture. The organic solvent used to disperse the colorant of this disclosure is not particularly limited as long as it does not develop color in the solvent, and conventional general-purpose organic solvents can be used. Examples include alcohol-based organic solvents, glycol-based organic solvents, glycol ether-based organic solvents, hydrocarbon-based organic solvents, ketone-based organic solvents, ester-based organic solvents, and the like. Examples of alcohol-based organic solvents include ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol, tert-butyl alcohol, tert-amyl alcohol, and benzyl alcohol. Examples of glycol-based organic solvents include ethylene glycol, diethylene glycol, propylene glycol, and benzyl glycol. Examples of glycol ether-based organic solvents include ethylene glycol monomethyl ether, ethylene glycol diethyl ether, ethylene glycol monoisopropyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether. Examples of hydrocarbon-based organic solvents include n-heptane, n-octane, isooctane, methylcyclohexane, ethylcyclohexane, toluene, xylene, ethylbenzene, and naphthalene. Examples of ketone-based organic solvents include methyl isobutyl ketone, methyl n-propyl ketone, methyl n-butyl ketone, and di-n-propyl ketone. Examples of ester-based organic solvents include n-butyl formate, isobutyl formate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, ethyl propionate, n-butyl propionate, methyl butyrate, and ethyl butyrate. These organic solvents may be used individually or in combination of two or more.

[0070] Furthermore, the printing ink composition and the writing instrument ink composition may also contain conventionally used additives, to the extent that they do not impair the water-color change performance.

[0071] When the colorants of this disclosure are applied to a printing ink composition, the printing ink composition may be a letterpress printing ink, an intaglio printing ink, a lithographic printing ink, a stencil printing ink, an on-demand printing ink, an offset printing ink, a digital offset printing ink, an inkjet printing ink, and the like.

[0072] When applying the colorant of this disclosure to an ink composition for writing instruments, the structure and shape of the writing instrument itself that is filled with the writing instrument ink are not particularly limited, and conventional general-purpose writing instruments can be used. These may include marking pens (sign pens) with fiber tips, felt tips, or plastic tips, ballpoint pens with ballpoint pen tips, or fountain pens with metal tips.

[0073] Furthermore, a writing instrument that can use a writing instrument ink composition may be one in which the ink composition is directly filled, or it may be equipped with an ink container or ink absorber that can be filled with writing instrument ink. Furthermore, the writing instrument may be an ink cartridge type or converter type in which the ink reservoir or ink absorber is detachably replaceable from the writing instrument body.

[0074] Furthermore, writing instruments that can use the ink composition for writing instruments include capped writing instruments equipped with a cap that covers the pen tip, and retractable writing instruments such as push-button, twist-button, and slide-button writing instruments in which the pen tip can be stored inside the barrel.

[0075] Furthermore, the supply mechanism for a writing instrument that can use an ink composition for writing instruments is not particularly limited; for example, (Mechanism 1) A mechanism that supplies an ink composition to the pen tip, comprising an ink guide section made of a fiber converging body or the like as an ink flow rate adjustment member. (Mechanism 2) A mechanism that includes a comb-shaped ink flow rate adjustment member, which is interposed to supply the ink composition to the pen tip. (Mechanism 3) A mechanism that supplies ink composition to the pen tip, equipped with an ink flow rate adjustment member by a valve mechanism. (Mechanism 4) A mechanism that directly supplies the ink composition to the pen tip without an ink flow rate adjustment member. Examples include:

[0076] Furthermore, the colorants of this disclosure may be coated with compounds or materials such as surfactants or resins. [Examples]

[0077] Examples of the water-color-changing materials of the present disclosure are shown below, but the invention is not limited to these examples. Note that the composition values ​​in the table represent parts by mass.

[0078] Example 1 Preparation of a water-color-changing composition A water-color-changing composition was prepared by mixing 2.0 parts of crystal violet lactone as an electron-donating color-changing organic compound, 8.0 parts of 1-phenyl-1,1-bis(4-hydroxyphenyl)ethane as an electron-accepting compound, and 40.0 parts of 3-methoxy-N,N-dimethylpropionamide as an amide compound in a heat-resistant glass container at 25°C for 30 minutes.

[0079] Preparation of water-color-changing materials Silica [manufactured by Mizusawa Chemical Industry Co., Ltd., product name: Mizukasil P-527, specific surface area: 60 m²] is placed in a separate heat-resistant glass container. 2 [130 mL / g, oil absorption capacity: 130 mL / 100 g] 50.0 parts were weighed out, and while stirring with a mixer at 25°C, 50.0 parts of the prepared water-color-changing composition were slowly added dropwise using a dropper, and then stirred for 30 minutes to prepare the water-color-changing material.

[0080] When a small amount of water-color-changing material, prepared using a dry spatula, was transferred to a Petri dish and tap water was added, it was confirmed that the material changed color from white to a deep blue. The discolored, water-color-changing material was stored for 30 minutes at 25°C, but remained a deep blue color with no further color change observed.

[0081] Table 1 below shows the water-color-changing materials of Examples 1-6 and Comparative Examples 1 and 2. The water-color-changing materials in Examples 2-6 and Comparative Examples 1 and 2 were prepared using the same method as in Example 1.

[0082] [Table 1]

[0083] The contents of the raw materials in Table 1 are explained according to the note numbers. (1) Crystal violet lactone (2) 2-anilino-3-methyl-6-(N-ethyl-Np-tolylamino)fluorane (3) 1-phenyl-1,1-bis(4-hydroxyphenyl)ethane (4) 1,1,1-Tris(4-hydroxyphenyl)ethane (5) 3-Methoxy-N,N-dimethylpropionamide (6) N,N-dimethylacrylamide (7) 1,3-dimethyl-2-imidazolidinone (8) Silica [Manufactured by Mizusawa Chemical Industry Co., Ltd., Product name: Mizukasil P-527, Specific surface area: 60 m²] 2 / g, oil absorption: 130mL / 100g] (9) Silica [Manufactured by AGC SI-TECH Co., Ltd., product name: Sunsphere H-32, specific surface area 700 m²] 2 / g, oil absorption: 300mL / 100g] (10) Silica [Manufactured by Fuji Silicia Chemical Co., Ltd., product name: Silicia 350, specific surface area 300 m²] 2 / g, oil absorption: 320mL / 100g]

[0084] Discoloration confirmation test 1 The hue of the water-color-changing materials in Examples 1-6 and Comparative Examples 1 and 2 was examined during color development, and the intensity was evaluated. The hue and evaluation results are shown in Table 1. A: A dark color was observed. B: While lighter than the A rating, a sufficiently dark color was observed that it poses no practical problems. C: A faint color was observed. D: A faint, barely visible color was observed, or no color was detected.

[0085] The water-color-changing materials in Examples 1-6 develop a deep color upon contact with moisture, and therefore also function as indicators for detecting moisture.

[0086] Preparation of ink composition Ink compositions were prepared by uniformly dispersing 5 parts by mass of each water-color-changing material prepared in Examples 1-6 and Comparative Examples 1 and 2 in 95 parts by mass of xylene at a temperature of 25°C. Each prepared ink composition was printed on report paper (writing paper A conforming to JIS P3201) using a bar coater to obtain test samples.

[0087] Discoloration confirmation test 2 The intensity of the color change was confirmed by spraying each test sample once with tap water using a spray bottle. The test results are shown in Table 2. A: A dark color was observed. B: While lighter than the A rating, a sufficiently dark color was observed that it poses no practical problems. C: A faint color was observed. D: A faint, barely visible color was observed, or no color was detected.

[0088] [Table 2]

[0089] These results suggest that the ink can be used not only as a colorant in ink compositions, but also as an indicator in printed materials.

[0090] Manufacturing of writing instruments The ink composition prepared in Example 1 was impregnated into an ink-absorbing body made of polyester sliver coated with a synthetic resin film, housed in a polypropylene barrel, a resin-processed pen body (bullet-shaped) made of polyester fiber was connected to the ink-absorbing body via a resin holder at the tip of the barrel, and a cap was attached to create a marking pen.

[0091] Discoloration confirmation test 3 Using the prepared marking pen, 12 spiral circles were continuously written in a single line on a report sheet of paper (writing paper A conforming to JIS P3201). After that, the entire surface was moistened with tap water using a spray bottle, and the color development was visually confirmed to be a deep blue.

[0092] These results confirm that the colorant of this disclosure can be used as a colorant in ink compositions for writing instruments.

Claims

1. A water-color-changing material comprising a water-color-changing composition containing an electron-donating color-changing organic compound, an electron-accepting compound, and an amide compound and / or an imidazolidinone compound, in a porous material.

2. The water-color-changing material according to claim 1, wherein the amide compound is an amide compound represented by general formula (1). 【Chemistry 1】 [In general formula (1), R1 and R2 are each independently organic groups having 1 to 30 carbon atoms, and R3 is one of an alkoxyalkyl group, an alkyl group, an alkenyl group, or a hydrogen atom.]

3. The water-color-changing material according to claim 1 or 2, wherein the imidazolidinone compound is an imidazolidinone compound represented by general formula (2). 【Chemistry 2】 [In general formula (2), R4 and R5 are each independently organic groups having 1 to 20 carbon atoms.]

4. The water-color-changing material according to any one of claims 1 to 3, wherein the porous material is an inorganic porous material.

5. The water-color-changing material according to any one of claims 1 to 4, wherein the porous material is a porous material having silanol groups.

6. A water-color-changing indicator comprising the water-color-changing material according to any one of claims 1 to 5.

7. A coloring agent comprising a water-color-changing material according to any one of claims 1 to 5.

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