Color changeable display

Abstract

To provide a color-changeable display body which does not release a volatile or sublimable useful agent in a normal state, can release the useful agent at an arbitrary timing, and has an indicator function capable of discriminating the progress and the end point of the release by changing the color with the release of the useful agent.SOLUTION: A color-change display comprising: a substrate; and a color-change layer provided on the substrate, the color-change layer containing microcapsules breakable by an external force, wherein the microcapsules contain a color-change composition comprising at least (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a volatile or sublimable beneficial agent having an action of inhibiting a color reaction between the component (a) and the component (b).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a color-changing indicator. [Background technology]

[0002] Conventionally, an indicator of the volatilization process has been disclosed, which is characterized by holding a substance consisting of a combination of an electron-donating color former, an electron-accepting color developer, and a volatile or sublimable desensitizing substance (e.g., fragrance and / or medicinal ingredient) in a container having a portion permeable to volatilized components (see, for example, Patent Document 1). The above-mentioned indicators contain a substance that changes color in correlation with the volatilization process of the stored components, making it possible to clearly identify the volatilization process and its end point. However, because the above-mentioned substance is a desensitizing substance that is normally released into the atmosphere, it is difficult to arbitrarily control the release of the desensitizing substance, which can sometimes limit the use of the indicators. Furthermore, there is a risk that the desensitizing substance may be released unintentionally from the indicator, which can make the indicator unusable without the user realizing it. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Microfilm of JP 63-212364 Summary of the Invention [Problem to be solved by the invention]

[0004] The present invention has been made based on the background technology described above, and aims to provide a color-changing indicator that can release a volatile or sublimable beneficial agent at any timing and that makes it possible to determine the progress and end point of the release. [Means for solving the problem]

[0005] The present invention provides a color-changing indicator comprising a substrate and a color-changing layer comprising microcapsules that can be broken by external force, the microcapsules encapsulating a color-changing composition comprising at least (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a volatile or sublimable benefit agent that inhibits the color-changing reaction of components (a) and (b). Further requirements include that the microcapsules have an average particle size of 5 to 50 μm, that the benefit agent is selected from the group consisting of fragrances, insect repellents, antibacterial agents, antiviral agents, bactericidal agents, disinfectants, antifungal agents, and antiseptic agents, and that an adhesive layer is provided on the surface of the substrate opposite to the surface on which the color-changing layer is provided. The present invention also provides a color-change indicator set comprising the color-change indicator and an external force application means, and further requires that the external force application means be a scraping tool. [Effects of the Invention]

[0006] The present invention provides a color-changing indicator that does not release a volatile or sublimable benefit agent under normal conditions, but can release the benefit agent at any timing, and has an indicator function that changes color as the benefit agent is released, allowing the progress and end point of the release to be determined. DETAILED DESCRIPTION OF THE INVENTION

[0007] The color-changing indicator of the present invention contains a color-changing composition comprising at least (a) an electron-donating color-forming organic compound, (b) an electron-accepting compound, and (c) a volatile or sublimable benefit agent having the effect of inhibiting the color-changing reaction of the (a) component and the (b) component, and has a color-changing layer containing microcapsules that can be destroyed by external force provided on a substrate.

[0008] Generally, (a) an electron-donating organic color-forming compound and (b) an electron-accepting compound can undergo a color reaction by donating and receiving electrons between them. However, if (c) a beneficial agent that has the effect of interfering with the color reaction of the (a) component and the (b) component is present, the donating and receiving of electrons between the electron-donating organic color-forming compound and the electron-accepting compound is inhibited, and the color reaction does not occur. In the microcapsules of the present invention, the beneficial agent component (C) is volatile or sublimable, but because the color-changing composition containing component (C) is encapsulated in the microcapsules, component (C) is not released from the microcapsules under normal conditions, and the color-changing layer containing the microcapsules is in a discolored state. On the other hand, when the microcapsules are broken by external force, component (C) volatilizes or sublimes from within the microcapsules, suppressing the effect of inhibiting the color-changing reaction of components (A) and (B). As a result, electrons are exchanged between the electron-donating color-forming organic compound and the electron-accepting compound, resulting in a color-changing reaction. In other words, when the microcapsules of the present invention are broken by external force, component (C) is released into the atmosphere, and the color-changing layer containing the microcapsules changes to a colored state (discolors). The color-changing indicator of the present invention can release component (C) into the atmosphere when the microcapsules are broken by applying an external force, and can therefore release component (C) at any desired timing. Furthermore, since the color-changing layer changes color at the location where the microcapsules are broken, it is possible to determine the progress and end point of the release of component (C).

[0009] Components (a), (b) and (c) of the composition applied to the present invention will be specifically explained below.

[0010] 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.

[0011] Examples of the electron-donating color-forming organic compound include a phthalide compound, a fluoran compound, a styrinoquinoline compound, a diazarhodamine lactone compound, a pyridine compound, a quinazoline compound, and a bisquinazoline compound. Examples of the phthalide compound include a diphenylmethane phthalide compound, a phenylindolyl phthalide compound, an indolyl phthalide compound, a diphenylmethane azaphthalide compound, a phenylindolyl azaphthalide compound, and derivatives thereof. Among these, the phenylindolyl azaphthalide compound and derivatives thereof are preferred. Examples of fluoran compounds include aminofluoran compounds, alkoxyfluoran compounds, and derivatives thereof.

[0012] Examples of compounds that can be used as component (a) are given below. 3,3-bis(4-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-n-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-propyl-2-methylindol-3-yl)-4-azaphthalide, 3,6-bis(diphenylamino)fluoran, 3,6-bis(N-phenyl-Np-tolylamino)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-chloroamino-6-di-n-butylaminofluoran, 2-(2-chloroanilino)-6-di-n-butylaminofluoran, 2-(3-trifluoromethylanilino)-6-diethylaminofluoran, 2-(3-trifluoromethylanilino)-6-di-n-pentylaminofluoran, 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, 6-diethylamino-1,2-benzofluoran, 6-(N-ethyl-N-isobutylamino)-1,2-benzofluoran, 6-(N-ethyl-N-isopentylamino)-1,2-benzofluoran, 2-(3-methoxy-4-dodecoxystyryl)quinoline, 2-diethylamino-8-diethylamino-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidin-5,1′(3′H)-isobenzofuran]-3′-one, 2-di-n-butylamino-8-di-n-butylamino-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidin-5,1′(3′H)-isobenzofuran]-3′-one, 2-di-n-butylamino-8-diethylamino-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidin-5,1′(3′H)-isobenzofuran]-3′-one, 2-di-n-butylamino-8-(N-ethyl-N-isoamylamino)-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidin-5,1′(3′H)-isobenzofuran]-3′-one, 2-di-n-butylamino-8-di-n-pentylamino-4-methylspiro[5H-[1]benzopyrano[2,3-d]pyrimidin-5,1′(3′H)-isobenzofuran]-3′-one, 4,5,6,7-tetrachloro-3-(4-dimethylamino-2-methoxyphenyl)-3-(1-n-butyl-2-methylindol-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-tetrachloro-3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindol-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-tetrachloro-3-(4-diethylamino-2-ethoxyphenyl)-3-(1-n-pentyl-2-methylindol-3-yl)-1(3H)-isobenzofuranone, 4,5,6,7-tetrachloro-3-(4-diethylamino-2-methylphenyl)-3-(1-ethyl-2-methylindol-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]

[0013] In addition, fluorans may be compounds having a substituent on the phenyl group forming the xanthene ring, or may be compounds that 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 chlorine atom), and that exhibit a blue or black color.

[0014] Component (b), ie, the electron accepting compound, is a compound that accepts electrons from component (a) and functions as a developer for component (a). 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 color-changing composition to cause component (A) to develop color), and a group of compounds having an electron vacancy.

[0015] Examples of compounds having an active proton include compounds having a phenolic hydroxy 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, and inorganic acids. Preferred examples of carboxylic acids and derivatives thereof include aromatic carboxylic acids and derivatives thereof, or aliphatic carboxylic acids having 2 to 5 carbon atoms and derivatives thereof. Examples of the pseudo-acidic compounds include metal salts of compounds having a phenolic hydroxy 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. Compounds having electron vacancies include borates, borate esters, and inorganic salts.

[0016] Compounds having a phenolic hydroxy 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 hydroxy group preferably has at least two benzene rings. In addition, the compound having a phenolic hydroxy group may have a substituent such as an alkyl group, an aryl group, an acyl group, an alkoxycarbonyl group, a carboxy group and its ester or amide group, or a halogen atom.

[0017] Examples of metals contained in metal salts of compounds having a phenolic hydroxy group include sodium, potassium, calcium, zinc, zirconium, aluminum, magnesium, nickel, cobalt, tin, copper, iron, vanadium, titanium, lead, and molybdenum.

[0018] Examples of compounds that can be used as component (b) are given below. Phenol, o-cresol, 4-np-nonylphenol, 4-n-octylphenol, 4-n-dodecylphenol, 4-n-stearylphenol, 4-chlorophenol, 4-bromophenol, 2-phenylphenol, n-butyl 4-hydroxybenzoate, n-octyl 4-hydroxybenzoate, 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)n-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-phenyl-1,1-bi 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)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(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'-dihydroxydiphenyl sulfone, 4-isopropoxy-4'-hydroxydiphenyl sulfone, 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),

[0019] The following describes component (c), a volatile or sublimable benefit agent that has the effect of inhibiting the color-changing reaction of components (a) and (b) (desensitizing effect). Component (c) has the effect of inhibiting the transfer of electrons between components (a) and (b) in the color-changing composition, but is not particularly limited as long as it allows the transfer of electrons between components (a) and (b) upon volatilization or sublimation. Volatile or sublimable benefit agents include, for example, fragrances, insect repellents, antibacterial ingredients, antiviral ingredients, germicidal ingredients, disinfectants, antifungal ingredients, antiseptic ingredients, and the like. Flavors are divided into food flavors and cosmetic flavors (fragrances), but food flavors are preferred from the viewpoint of safety. Insect repellent components include insect repellent components and insecticidal components, such as pyrethroid compounds, neonicotinoid compounds, organochlorine compounds, organophosphorus compounds, carbamate compounds, and oxadiazine compounds, with pyrethroid compounds being preferred from the viewpoint of safety.

[0020] Examples of compounds that can be used as component (c) are given below. Pyrethroid compounds such as pyrethrins, allethrin, phthalthrin, resmethrin, furamethrin, phenothrin, permethrin, empenthrin, prallethrin, imiprothrin, metofluthrin, transfluthrin, cyfluthrin, profluthrin, monfluthrin, cyphenothrin, fenpropathrin, deltamethrin, fenvalerate, tralomethrin, telallethrin, etofenprox, and bifenthrin; Essential oils such as grapefruit oil, orange oil, lemon oil, lime oil, jasmine oil, peppermint oil, rosemary oil, nutmeg oil, cassia oil, lavender oil, cypress oil, Japanese cypress oil, fennel oil, terpene-less lemon oil, and terpene-less orange oil; Methanol, ethanol, propanol, 1-butanol, 1-pentanol, isoamyl alcohol, 1-hexanol, 1-heptanol, 1-octanol, 2-nonanol, 1-decanol, 1-undecanol, 2-dodecanol, 2,3-butanediol, ethoxyethanol, 1-octen-3-ol, furfuryl alcohol, linalool, tetrahydrolinalool, nerol, citronellol, lavandulol, myrcenol, α-terpineol, borneol, nopol, isobornylcyclohexanol, farnesol, nerolidol, santalol, cedrol, patchouli alcohol, benzyl alcohol, phenethyl alcohol, γ alcohols such as -phenylpropyl alcohol, cinnamyl alcohol, anise alcohol, α,α-dimethylphenethyl alcohol, α-phenylethanol, β-phenylethyldimethylcarbinol, phenoxyethanol, 4-tert-butylcyclohexanol, 6-(E)-nonenol, mentha-1,8-dien-4-ol, mentha-8-ene-1,2-diol, ipsenol, ipsidienol, (Z)-verbenol, 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethanol, 1,1-bis(4-chlorophenyl)ethanol, di(p-chlorophenyl)cyclopropylmethanol, and p-menthane-3,8-diol; aromatic ethers such as diphenyl ether, p-methylanisole, anethole, methyl eugenol, methyl isoeugenol, benzyl isoeugenol, safrole, isosafrole, methyl-β-naphthyl ether, and ethyl-β-naphthyl ether; Aliphatic aldehydes such as formaldehyde, acetaldehyde, propanal, n-butanal, isobutanal, n-pentanal, n-hexanal, n-heptanal, n-octanal, n-nonanal, n-decanal, n-undecanal, n-dodecanal, n-octadecanal, 2-methylundecanal, n-tridecanal, n-tetradecanal, n-hexadecanal, trans-2-hexenal, 2,6-nonadienal, glyoxal, acrolein, and crotonaldehyde; terpene aldehydes such as citral, citronellal, hydroxycitronellal, perillaldehyde, citronellyloxyacetaldehyde, lyral, sinensal, and myrtenal; Aromatic aldehydes such as benzaldehyde, phenylacetaldehyde, furfural, 2-allyloxy-3-ethoxybenzaldehyde, 3-phenylpropionaldehyde, cinnamaldehyde, α-amylcinnamaldehyde, α-hexylcinnamaldehyde, anisaldehyde, cuminaldehyde, heliotropin, cyclamen aldehyde, p-tert-butyl-α-methyldihydrocinnamaldehyde, vanillin, and ethyl vanillin; aliphatic ketones such as 2-butanone, 2-pentanone, 2-hexanone, 2-heptanone, 3-heptanone, 2-octanone, 3-octanone, 2-nonanone, 2-decanone, 2-undecanone, 4-ethoxy-2-butanone, 2,3-pentanedione, 2,3-hexanedione, and 3-hydroxy-2-pentanone; terpene ketones such as carvone, menthone, and prevone; Monoterpenes such as geraniol, menthol, pinene, limonene, and camphor aromatic ketones such as p-methylacetophenone, p-methoxyacetophenone, benzophenone, benzylideneacetone, anisylacetone, p-hydroxybenzylacetone, 2-acetonaphthone, and 4-(p-acetoxyphenyl)-2-butanone; alicyclic ketones, alicyclic ethers, or alicyclic lactones such as α-ionone, β-ionone, γ-ionone, α-n-methylionone, β-n-methylionone, γ-n-methylionone, α-isomethylionone, β-isomethylionone, γ-isomethylionone, α-irone, β-irone, γ-irone, α-damascenone, β-damascenone, α-damascone, β-damascone, γ-damascone, theaspirane, theaspirone, ezran, rosefuran, nootkatone, α-vetivone, cis-jasmone, cymodrojasmone, methyl jasmonate, methyl dihydrojasmonate, jasmine lactone, maltol, cyclotene, and furaneol; Macrocyclic ketones or macrocyclic lactones such as muscone, civetone, cyclopentadecane, cyclopentadecanolide, ampletolide, cyclopentadecanolide, ethylene brassillade, 12-oxahexadecanolide, 11-oxahexadecanolide, 10-oxahexadecanolide, etc.; Synthetic musks such as musk ketone, musk amplet, celestolide, fantolide, and tonalide; cyclic ethers such as rose oxide, oxide ketone, linalool oxide, and 1,8-cineole; acetals such as citral dimethyl acetal, citral diethyl acetal, hydroxycitronellal dimethyl acetal, and phenylacetaldehyde dimethyl acetal; Methyl formate, ethyl formate, isopropyl formate, butyl formate, isoamyl formate, hexenyl formate, geranyl formate, benzyl formate, phenethyl formate, methyl acetate, ethyl acetate, propyl acetate, n-butyl acetate, amyl acetate, isoamyl acetate, n-hexyl acetate, n-heptyl acetate, n-octyl acetate, citronellyl acetate, geranyl acetate, linalyl acetate, l-menthyl acetate, bornyl acetate, isobornyl acetate, terpinyl acetate, benzyl acetate phenyl acetate, phenethyl acetate, cinnamyl acetate, anisyl acetate, acetylisoeugenol, myrcenyl acetate, cedryl acetate, 4-tert-butylcyclohexyl acetate, 1,1-dimethylphenylethyl acetate, ethyl propionate, propyl propionate, isoamyl propionate, citronellyl propionate, linalyl propionate, geranyl propionate, terpinyl propionate, benzyl propionate, cinnamyl propionate, propionyl Phenethyl butyrate, Ethyl butyrate, n-Propyl butyrate, n-Butyl butyrate, Isoamyl butyrate, Geranyl butyrate, Linalyl butyrate, Benzyl butyrate, Phenethyl butyrate, Ethyl isobutyrate, Isoamyl isobutyrate, Benzyl isobutyrate, Phenethyl isobutyrate, Butyl n-Valerate, Isoamyl n-Valerate, Geranyl n-Valerate, Methyl caproate, Propyl caproate, Isoamyl caproate, Phenethyl caproate, Methyl enanthate, Ethyl enanthate esters of aliphatic carboxylic acids such as methyl caprylate, methyl pelargonate, ethyl caprate, methyl laurate, methyl palmitate, ethyl acetoacetate, ethyl levulinate, methyl 6-(E)-nonenoate, 2-(E)-hexenyl acetate, tert-butyl 2-methyl-4-cyclohexenecarboxylate, ethyl butylacetylaminopropionate, and sec-butyl 2-(2-hydroxyethyl)piperidine-1-carboxylate; Esters of aromatic carboxylic acids such as methyl benzoate, ethyl benzoate, isobutyl benzoate, isoamyl benzoate, benzyl benzoate, ethyl phenylacetate, methyl cinnamate, ethyl cinnamate, isobutyl salicylate, isoamyl salicylate, benzyl salicylate, methyl salicylate, and ethyl anisate; amines such as methylamine, ethylamine, propylamine, isopropylamine, triethylamine, n-butylamine, isobutylamine, dimethylamine, trimethylamine, isopentylamine, pentylamine, ethanolamine, 2-phenethylamine, n-hexylamine, 1,4-diaminobutane, methyl anthranilate, methyl N-methylanthranilate, and ethyl anthranilate; amides such as N-ethylacetamide, N-(isobutyl)acetamide, N-(2-methylbutyl)acetamide, N-(2-phenethyl)acetamide, and N,N-diethyl-3-methylbenzamide; phosphate esters such as 2-chloro-1-(2,4-dichlorophenyl)vinyl diethyl phosphate, dimethyl-2,2-dichlorovinyl phosphate, and dimethyl-2,2,2-trichloro-1-hydroxyethyl phosphonate; thiophosphates such as O,O-diisopropyl-S-ethylsulfenylmethyldithiophosphate, O,O-dimethyl-S-2-(ethylsulfenyl)isopropylthiophosphate, O,O-dimethyl-O-(3-methyl-4-nitrophenyl)thiophosphate, and O,O-diisopropyl-S-benzylthiophosphate; thiols such as methanethiol, ethanethiol, and furfuryl mercaptan; Thioethers such as dimethyl sulfide, diethyl sulfide, butyl ethyl sulfide, diisopropyl sulfide, diallyl sulfide, 3-(methylthio)-propyl acetate, and methyl β-methylthiopropionate; Disulfides such as dimethyl disulfide and diethyl disulfide; Sulfoxides such as dimethyl sulfoxide; Heterocyclic compounds such as 6-methylquinoline, 7-methylquinoline, 6-isopropylquinoline, 2-methyltetrahydroquinoline, 6-methyltetrahydroquinoline, 2-isobutylthiazole, 2-methylpyrazine, 2-ethylpyrazine, 2,5-dimethylpyrazine, 3,5,6-trimethylpyrazine, 2,3,5,6-tetramethylpyrazine, and methyl-2-pyrazinyl ketone

[0021] The color-changing composition is a compatible solution containing the above components (A), (B), and (C) as essential components, and the ratio of each component depends on the concentration, solubility, and type of each component. Generally, the component ratio that achieves the desired properties is 1:1 of component (A): 0.1 to 100, preferably 0.1 to 50, more preferably 0.5 to 20, of component (B), and 1 to 800, preferably 5 to 200, more preferably 10 to 100, of component (C) (all ratios are in parts by mass).

[0022] The microcapsules are composed of a wall (wall material) and an encapsulated substance (including a color-changing composition) encapsulated therein. Examples of the resin that constitutes the wall (i.e., the wall-forming material) include urea resin, urethane resin, urea-urethane resin, epoxy resin, melamine resin, benzoguanamine resin, and isocyanate resin.

[0023] Various additives such as antioxidants, ultraviolet absorbers, infrared absorbers, and dissolution aids may also be added to the microcapsules as long as they do not affect their functions.

[0024] Microcapsules can be produced by a microencapsulation method, such as a known isocyanate-based interfacial polymerization method, an in situ polymerization method such as a melamine-formalin-based method, a liquid curing coating method, a phase separation method from an aqueous solution, a phase separation method from an organic solvent, a melt-dispersion cooling method, an air suspension coating method, or a spray drying method, and the method can be appropriately selected depending on the application. Depending on the purpose, the surface of the microcapsules may be further provided with a resin film or the like, thereby imparting durability or modifying the surface properties.

[0025] The microcapsules preferably have a mass ratio of encapsulated material to wall membrane of 7:1 to 1:1. By having the mass ratio of encapsulated material to wall membrane within the above range, the amount of beneficial agent encapsulated in the microcapsules is sufficient, and the visibility of discoloration when the microcapsules are broken can be improved. More preferably, the mass ratio of encapsulated material to wall membrane is 6:1 to 1:1.

[0026] The average particle size of the microcapsules is not particularly limited, but is preferably 5 to 50 μm, more preferably 10 to 30 μm. If the average particle size exceeds 50 μm, the dispersion stability in the ink or paint tends to be lacking. On the other hand, if the average particle size is less than 5 μm, the amount of benefit agent encapsulated in the microcapsules tends to be insufficient.

[0027] The average particle diameter 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 diameter of particles equivalent to a sphere of equal volume using this value. 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 (Beckman Coulter, Inc., product name: Multisizer 4e). 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 above software or a measuring device using the Coulter method.

[0028] The color-changing indicator of the present invention can be obtained by printing or applying a color-changing liquid composition, such as ink or paint, containing microcapsules in a vehicle containing a binder resin onto a substrate, thereby providing a color-changing layer on the substrate. Examples of methods for printing or applying the color-changing liquid composition on a substrate include printing methods such as screen printing, offset printing, gravure printing, coater printing, and transfer printing, and application methods such as brush coating, spray coating, electrostatic coating, electrodeposition coating, flow coating, roller coating, and dip coating.

[0029] The color-changing indicator of the present invention can also be configured to change color from one color to a different color when the microcapsules are ruptured by the application of an external force by using a non-color-changing colorant such as a general dye or pigment. By changing color from one color to a different color, i.e., from a first color to a second color, the color-changing indicator can exhibit a variety of colors. Here, the color change from one color to a different color includes a change in color tone (e.g., from a light color to a dark color) and a change in hue (e.g., from pink to purple, or from yellow to green).

[0030] A color-changing indicator that changes color from one color to a different color can be produced, for example, by printing or applying a color-changing liquid composition, such as ink or paint, that combines microcapsules and a non-color-changing colorant onto a substrate to form a color-changing layer on the substrate. Here, the color (first color) refers to the color due to the non-color-changing colorant. The color (second color) that is different from the color (first color) refers to a mixture of the color due to the color reaction of components (A) and (B) that occurs when the microcapsules are destroyed by the application of external force and the color due to the non-color-changing colorant.

[0031] The color-changing liquid composition using a combination of microcapsules and a non-color-changing colorant may be either a composition in which microcapsules containing a non-color-changing colorant are dispersed in a vehicle, or a composition in which microcapsules and a non-color-changing colorant are separately dispersed in a vehicle. Examples of microcapsules containing a non-color-changing colorant include microcapsules containing both a color-changing composition and a non-color-changing colorant, and microcapsules containing a color-changing composition and whose wall is colored with a non-color-changing colorant.

[0032] A color-changing indicator that changes color from one color to a different color can be produced, for example, by printing or applying a non-color-changing liquid composition such as ink or paint containing a non-color-changing colorant onto a substrate to form a non-color-changing layer on the substrate, and then printing or applying a color-changing composition onto the non-color-changing layer to form a color-changing layer on the non-color-changing layer. The non-color-changing layer and the color-changing layer may be the same or different in size and shape, but it is preferable that they be the same in size and shape. Here, the color (first color) refers to the color due to the non-color-changing colorant. The color (second color) that is different from the color (first color) refers to a mixture of the color due to the color reaction of components (A) and (B) that occurs when the microcapsules are destroyed by the application of external force and the color due to the non-color-changing colorant. Examples of methods for printing or applying the non-discoloring liquid composition onto a substrate include printing methods such as screen printing, offset printing, gravure printing, coater printing, and transfer printing, and application methods such as brush coating, spray coating, electrostatic coating, electrodeposition coating, flow coating, roller coating, and dip coating.

[0033] The color-changing layer and the non-color-changing layer are formed by drying and solidifying a liquid composition, and are formed from components other than volatile components. The color-changing and non-color-changing liquid compositions may be printed or applied once to a substrate or a non-color-changing layer, and then dried and solidified to form a color-changing and non-color-changing layer, but the density of the color-changing and non-color-changing layers can be improved by printing or applying the liquid composition multiple times.

[0034] The binder resin is not particularly limited as long as it does not affect the color development or color change of the microcapsules or the color development of the non-color-changing colorant. Examples include ionomer resins, isobutylene-maleic anhydride copolymer resins, acrylonitrile-acrylic styrene copolymer resins, acrylonitrile-styrene copolymer resins, acrylonitrile-butadiene-styrene copolymer resins, acrylonitrile-chlorinated polyethylene-styrene copolymer resins, ethylene-vinyl chloride copolymer resins, ethylene-vinyl acetate copolymer resins, ethylene-vinyl acetate-vinyl chloride graft copolymer resins, vinylidene chloride resins, vinyl chloride resins, chlorinated vinyl chloride resins, vinyl chloride-vinylidene chloride copolymer resins, chlorinated polyethylene, chlorinated polypropylene, polyamide, polyethylene terephthalate, polybutylene terephthalate, polycarbonate, polystyrene, high-impact polystyrene, polypropylene, polymethylstyrene, polyacrylic esters, polymethyl methacrylate, epoxy acrylate resins, alkylphenol resins, and rosin. Examples of the resin include modified phenolic resins, rosin-modified alkyd resins, phenolic resin-modified alkyd resins, epoxy resin-modified alkyd resins, styrene-modified alkyd resins, acrylic-modified alkyd resins, aminoalkyd resins, vinyl chloride-vinyl acetate resins, styrene-butadiene resins, epoxy resins, unsaturated polyesters, saturated polyesters, polyurethanes, alkyd resins, natural rubber, polyisobutylene, butyl rubber, polyvinyl alkyl ethers, rosin, rosin esters, rosin derivatives, polyterpenes, oil-soluble phenolic resins, petroleum-based hydrocarbon resins, shellac, cyclized rubbers, vinyl acetate-based emulsion resins, styrene-butadiene-based emulsion resins, acrylic acid ester-based emulsion resins, water-soluble alkyd resins, water-soluble melamine resins, water-soluble urea resins, water-soluble phenolic resins, water-soluble epoxy resins, water-soluble polybutadiene, cellulose acetate, cellulose nitrate, and ethyl cellulose.

[0035] The 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.

[0036] The color-changing layer and the non-color-changing layer may be a solid pattern, or may be a shape such as a circle, oval, square, or rectangle; various letters; symbols; patterns; or images of people, animals, plants, fruits, foodstuffs, vehicles, buildings, celestial bodies, etc.

[0037] The substrate constituting the color-changing indicator according to the present invention is not particularly limited, and examples thereof include paper, synthetic paper, fiber, fabric, synthetic leather, leather, plastic, glass, elastomer, rubber, ceramic material, metal, wood, stone, etc. The shape is not limited to a flat shape, and may be uneven. By using a colored substrate, the color-changing indicator can be configured to change color from one color to a different color when the microcapsules are destroyed by application of an external force.

[0038] The color-change indicator may also be provided with an adhesive layer on the surface that comes into contact with the object (the surface of the color-change indicator opposite to the surface on which the color-change layer is provided). The adhesive used in the adhesive layer is not particularly limited as long as it can be attached to an object, and examples of the adhesive include acrylic resins, urethane resins, ethylene-vinyl acetate copolymer resins, rubber resins, silicone resins, and epoxy resins.

[0039] In the color-changing indicator of the present invention, the microcapsules in the color-changing layer can be destroyed by applying an appropriate external force. Examples of the means for applying external force include rubbing with fingers or nails, or a scraping tool. When rubbing with fingers or nails, there is a risk that the contents of the microcapsules may adhere to the fingers or nails, so it is also preferable to use a scraping tool.

[0040] The scraping tool is not particularly limited, and for example, a friction member or friction body that generates friction when scraped can be used. As the friction member and friction body, elastic bodies such as elastomers and plastic foams that are highly elastic and generate appropriate friction when scraped are preferred, but plastic molded bodies, stone, wood, metal, fabric, etc. can also be used. Note that while a general eraser can be used as the friction body and friction member, eraser dust is generated when scraped, so the above-mentioned friction member and friction body that generate almost no eraser dust are preferred. Examples of materials for the friction member and friction body include silicone resin and styrene-ethylene-butadiene-styrene block copolymer (SEBS resin).

[0041] The color-change indicator according to the present invention can also be combined with a friction member or friction body of any shape that is separate from the color-change indicator to form a color-change indicator set.

[0042] In the color-changing indicator of the present invention, the beneficial agent is released in an amount corresponding to the microcapsules being destroyed by applying an external force to the color-changing layer. In other words, any amount of beneficial agent can be released by adjusting the area where the external force is applied to the color-changing layer.

[0043] In the color-changing indicator of the present invention, the color-changing layer changes color where the beneficial agent has been released, and the released areas are clearly distinguishable from unused areas that have not changed color, so that even after the indicator has been used once, the indicator can be used repeatedly until the entire color-changing layer changes color. Furthermore, since the area where the benefit agent has been released undergoes an irreversible color change, by breaking the microcapsules to form an image, the image becomes visible on the color-changing layer when the release of the benefit agent is complete. This allows, for example, the current time to be written on the color-changing layer by applying an external force, and an image of the time when the benefit agent release started will appear when the release of the benefit agent is complete, so that the color-changing indicator can record the history of the time when the benefit agent release started. In other words, it can be used to later check when the benefit agent release started.

[0044] The color-changing indicator of the present invention can be applied to a variety of uses by changing the type of beneficial agent encapsulated in the microcapsules. For example, when a fragrance is encapsulated, it can be used as an air freshener for living spaces such as rooms or toilets, or for vehicles. When an insect repellent component for clothing pests is encapsulated, it can be used as an insect repellent for dolls or clothing. When an insect repellent component is encapsulated, it can be used as an insect repellent for homes such as entranceways or balconies, or as an insect repellent for humans or pets.

[0045] The color-changing indicator may be contained in a container having holes for allowing application of an external force to the color-changing layer and release of the benefit agent, and may also be provided with a fastener such as a string or clip for fixing or hanging on an object. When wearing the color-changing indicator, an adhesive layer can be provided on the color-changing indicator to allow it to be attached to the skin, clothing, shoes, personal belongings, etc., or a fixing device such as a clip can be attached to fix it to clothing, shoes, personal belongings, etc. It can also be worn on the wrist or ankle in the form of a band, bracelet or ring, or attached to a personal item in the form of a strap, or hung from the neck. [Example]

[0046] Examples are shown below. Unless otherwise specified, "parts" in the examples refer to "parts by mass."

[0047] Example 1 Preparation of microcapsules A color-changing composition consisting of 1 part 3-[2-ethoxy-4-(N-ethylanilino)phenyl]-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide as component (A), 2 parts 1,1-bis(4-hydroxyphenyl)-2-ethylhexane as component (B), and 50 parts 1,8-cineole as component (C) was mixed with 25 parts of an aromatic isocyanate prepolymer as a wall film forming material, and then emulsified and dispersed in an 8% aqueous polyvinyl alcohol solution. The mixture was heated and stirred to prepare a microcapsule dispersion. Microcapsules with an average particle size of 13.6 μm were obtained from the microcapsule dispersion by centrifugation.

[0048] Example 2 Preparation of microcapsules A color-changing composition consisting of 2 parts of 3-[2-ethoxy-4-(N-ethylanilino)phenyl]-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide as component (A), 5 parts of 1,1-bis(4-hydroxyphenyl)-2-ethylhexane as component (B), and 50 parts of 1,8-cineole as component (C) was added to a mixed solution consisting of 25 parts of an aromatic isocyanate prepolymer as a wall-forming material and 10 parts of a cosolvent, and then emulsified and dispersed in an 8% aqueous polyvinyl alcohol solution. The mixture was heated and stirred to prepare a microcapsule dispersion. Microcapsules with an average particle size of 23.1 μm were obtained from the microcapsule dispersion by centrifugation.

[0049] The microcapsules of Examples 3 to 5 were prepared in the same manner as in Example 2, except that the types and amounts of the materials to be blended were changed to those shown in Table 1 below.

[0050] Comparative Example 1 Preparation of microcapsules 50 parts of 1,8-cineole (component (c)) and 25 parts of aromatic isocyanate prepolymer (wall film forming material) were mixed, and then emulsified and dispersed in an 8% aqueous polyvinyl alcohol solution. The mixture was heated and stirred to prepare a microcapsule dispersion. Microcapsules with an average particle size of 21.8 μm were obtained from the microcapsule dispersion by centrifugation.

[0051] [Table 1]

[0052] The materials in Table 1 are as follows: A-1 3-[2-ethoxy-4-(N-ethylanilino)phenyl]-3-(1-ethyl-2-methylindol-3-yl)-4-azaphthalide, A-2 2-anilino-3-methyl-6-di-n-butylaminofluoran B-1 1,1-bis(4-hydroxyphenyl)-2-ethylhexane B-2 1-phenyl-1,1-bis(4-hydroxyphenyl)ethane B-3 4,4'-[1-{4-[1-(4-hydroxyphenyl)-1-methylethyl]phenyl}ethylidene]bisphenol C-1 1,8-cineole C-2 Picaridin (Icaridin) C-3 Lemon oil

[0053] [Preparation of test samples (color-changing indicators)] Inks were prepared by mixing 40 parts of each of the microcapsules obtained in Examples 1 to 5 and Comparative Example 1, 52 parts of an ethylene-vinyl acetate copolymer resin emulsion, 5 parts of a thickener, and 3 parts of a leveling agent. A solid pattern was screen-printed on high-quality paper using the ink to provide a color-changing layer on the high-quality paper, and a color-changing indicator was obtained as a test sample.

[0054] [Checking the emission function] The discoloration layer of each test sample was scraped using a scraping tool equipped with a dome-shaped SEBS resin as a friction member, and the presence or absence of odor after scraping was confirmed. The microcapsules were then broken by scraping the discoloration layer, and an evaluation was made to see whether component (C) was released. The evaluation results are shown in Table 2, and a rating of "A" was considered a pass. A: After rubbing, an odor originating from component (c) was detected, and the discoloration layer had the function of releasing component (c) as the microcapsules were destroyed. B: No odor originating from component (c) was detected even when rubbed, and the discoloration layer did not have the function of releasing component (c) when the microcapsules were destroyed.

[0055] [Confirming the color-changing function] After the above-mentioned release function confirmation test was performed, the presence or absence of discoloration at the scratched area was confirmed. Then, when the color-changing layer was scratched to destroy the microcapsules, it was evaluated whether the color-changing layer changed color with the release of component (C). The evaluation results are shown in Table 2, and a rating of "A" was considered to be acceptable. A: The scraped area of ​​the discolored layer changed color as component (C) was released, allowing the progress and end point of the release to be determined. B: The scraped area of ​​the discolored layer did not change color with the release of component (c), and the progress and end point of the release could not be determined.

[0056] [Table 2]

[0057] Application example 1 Making insect repellents An insect repellent was prepared by providing an adhesive layer on the surface of the color-changing indicator of Example 1 opposite to the surface on which the color-changing layer was provided. When this was attached to shoes, no odor or change in the color-changing layer was observed under normal conditions, and component (c) (insect repellent component) could be released at any time. When part of the color-changing layer was scratched with a fingernail, the microcapsules were destroyed, the odor from component (c) was detected, and the color-changing layer turned blue, allowing the progress of release to be visually confirmed. After a while, the end point of release could be determined. Furthermore, the amount of insect repellent component released could be adjusted by adjusting the area of ​​the color-changing layer scratched. This insect repellent could be used repeatedly until the entire color-changing layer had changed color, even after one use.

[0058] Application example 2 Making insect repellents A bracelet-shaped insect repellent was prepared by screen printing the ink of Example 3 onto the surface of a bracelet made of colorless, transparent HIPS (high impact polystyrene resin) as the base material. When worn on the wrist, no odor or change in the color-changing layer was detected under normal conditions, and component (C) (insect repellent component) could be released at any time. When part of the color-changing layer was scratched with the fingernail, the microcapsules were destroyed, the odor originating from component (C) was detected, and the color-changing layer turned blue, allowing the progress of release to be visually confirmed. After a while, the end point of release could be determined. Furthermore, the amount of insect repellent component released could be adjusted by adjusting the area of ​​the color-changing layer scratched. This insect repellent could be used repeatedly until the entire color-changing layer had changed color, even after one use.

[0059] Application example 3 Making insect repellents The color-changing indicator of Example 4 was housed in a container with holes to allow the color-changing layer to be rubbed and the component (C) to be released. A string was then attached to create a strap-type insect repellent. A scraping tool equipped with a dome-shaped SEBS resin as a friction member was then attached to the strap to create a set of insect repellent and scraping tool (color-changing indicator set). When this was worn around the neck, no odor or change in the color-changing layer was observed under normal conditions, and the component (C) (insect repellent component) could be released at any time. When the current time was written on the color-changing layer using the attached scraping tool, the microcapsules were destroyed, the odor originating from the component (C) was confirmed, and the color-changing layer turned black, allowing the progress of release to be visually confirmed. After a while, the image of the written time became clearly visible, allowing the start time of release to be recorded as a history, and the end point of release to be determined. Furthermore, the amount of insect repellent component released could be adjusted by adjusting the area of ​​the color-changing layer rubbed. Even after one use, this insect repellent could be used repeatedly until the entire area of ​​the color-changing layer was discolored.

[0060] Application example 4 Making insect repellents A non-color-changing layer was formed on white wood-free paper as a substrate by screen printing using a pink non-color-changing ink. A color-changing layer was then formed on the non-color-changing layer by screen printing using the ink of Example 5, producing a color-changing indicator. An adhesive layer was formed on the side of this color-changing indicator opposite the side on which the color-changing layer was formed, producing an insect repellent. Because the pink non-color-changing layer was located below the color-changing layer, the color-changing layer appeared pink. When this was applied to a window, no odor or change in the color-changing layer was observed under normal conditions, and component (c) (insect repellent component) could be released at any time. When part of the color-changing layer was scratched with a fingernail, the microcapsules were destroyed, the odor originating from component (c) was detected, and the color-changing layer changed from pink to purple, allowing the progress of release to be visually confirmed. After a while, the end point of release could be determined. Furthermore, the amount of insect repellent component released could be adjusted by adjusting the area of ​​the color-changing layer scratched. Even after one use, this insect repellent could be used repeatedly until the entire area of ​​the color-changing layer was discolored.

Claims

1. A color-changing indicator is provided on a substrate and includes a color-changing layer containing microcapsules that can be broken by external force, and the microcapsules contain a color-changing composition that is at least composed of (i) an electron-donating color-forming organic compound, (ii) an electron-accepting compound, and (iii) a volatile or sublimable benefit agent that has the effect of inhibiting the color-changing reaction of the components (i) and (ii).

2. 2. The color-changing indicator according to claim 1, wherein the microcapsules have an average particle size of 5 to 50 μm.

3. 3. The color-changing indicator according to claim 1, wherein the beneficial agent is selected from the group consisting of fragrances, insect repellents, antibacterial components, antiviral components, bactericidal components, disinfectants, antifungal components, and antiseptic components.

4. 4. The color-change indicator according to claim 1, wherein an adhesive layer is provided on the surface of the substrate opposite to the surface on which the color-change layer is provided.

5. A color-change indicator set comprising the color-change indicator according to any one of claims 1 to 4 and an external force applying means.

6. 6. The color-change indicator set according to claim 5, wherein the external force applying means is a scraping tool.

Images