JPS6147191B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel temperature-indicating material that reversibly changes color in response to temperature changes. Conventionally, as temperature-indicating materials, there are those using metal complex salt crystals and those using cholesteric liquid crystals. However, the former contains heavy metal salts, generally has a high discoloration temperature, and has the disadvantage of having a small hue, while the latter has short lifespan, relatively low temperature range, and high price. However, there are many restrictions and inconveniences in using it as a temperature-indicating material. Therefore, it has been desired to develop a temperature-indicating material that can freely select the color change temperature and hue, exhibits sharp color change, has good durability, and is inexpensive. Recently, temperature-indicating materials using electron-donating color-forming organic compounds have been proposed as temperature-indicating materials that take this point into consideration (for example, Japanese Patent Publication No. 44706/1983,
JP-A No. 53-102284, etc.). These all include an electron-donating color-forming organic compound, an acidic substance having a phenolic hydroxyl group or a carboxylic acid group that causes the organic compound to develop color, and alcohol,
Basically 3 with ether, ester, ketone etc.
It is composed of a component system, and the hue, density, and color change temperature can be freely changed depending on the type and combination of each component. However, printed matter or molded products using these temperature-indicating materials generally have poor light resistance, with noticeable fading or loss of color change ability after being exposed to direct sunlight for more than 10 hours, and few of them can withstand practical use. The inventors of the present invention have conducted intensive research to solve the various problems mentioned above, and as a result, have discovered a completely new type of temperature-indicating material. That is, the present invention provides (A) an electron-accepting color-changing organic compound consisting of phthalein or fluorescein and their derivatives, (B) an organic nitrogen compound exhibiting electron-donating properties to the compound (A), and (C ) A reversible temperature-indicating material characterized by containing a compound that causes the discoloration effect of compound (B) on compound (A) to disappear at a specific temperature. The temperature-indicating material contains the above compound (A)
Various hues can be controlled depending on the type of compound (B) or (C), color density can be controlled freely depending on the amount of compound (C), and discoloration temperature can be controlled freely depending on the type of compound (C). It has extremely good physical properties including durability. Hereinafter, the above-mentioned present invention will be explained in detail. First, the electron-accepting color-changing organic compound that can be used in the present invention refers to the electron-donating color-changing organic compounds that have already been proposed (for example, phthalide compounds such as crystal violet lactone, fluoran compounds, phenothiazine compounds, spiropyran compounds, etc.). The phthalenes and fluorescenes are preferably used as phthaleins and fluorescenes, but the ones shown by the following general formulas are preferably used. The invention is not limited to these. Here, X: -OH, -OCOR, -H (R is a phenyl group, a lower alkyl group up to _C4 ) B: -CO-, _-SO2 - A: B and O and the central carbon bonded to O It represents a saturated or unsaturated carbon atomic group necessary to form a 5-membered ring or a 6-membered ring with this atomic group, and includes those fused to this atomic group such as a benzene ring, a halogen-substituted benzene ring, a naphthalene ring, a cyclohexane ring, etc. It can be done. Specifically, the organic compounds mentioned above include the following compounds. Namely, thymolphthalein, phenolphthalein, O-phresolphthalein,
1,4-dimethyl-5-hydroxybenzenesulfophthalein, thymolsulfophthalein,
m-cresol sulfophthalein, α-naphthol sulfophthalein, O-cresol sulfophthalein, phenolsulfophthalein, sibromothymol sulfophthalein, dibromophenoltetrabromophenol sulfophthalein,
Dibromophenolsulfophthalein, dibromo-o-cresolsulfophthalein, dichlorophenolsulfophthalein, tetrabromo-m-cresolsulfophthalein, dibromodichlorophenolsulfophthalein, tetrabromophenoltetrabromosulfophthalein rhein, tetrabromophenol sulfophthalein, dibromopyrogallol sulfophthalein,
These include fluorescein, sulfofluorescein, tetrabromofluorescein, tetrachlorofluorescein, and the like. Next, the organic nitrogen compound exhibiting electron-donating properties used in the present invention may be any compound as long as it exhibits a color-changing effect on the electron-accepting color-changing organic compound.
Specifically, primary, secondary, and tertiary aliphatic amines in which the hydrogen atom of ammonia is substituted with an alkyl group, such as ethylamine, butylamine, octylamine, dodecylamine, stearylamine, dipropylamine, diamylamine, and tripropylamine. , tributylamine, allylamine, cyclohexylamine, etc.; primary, secondary, and tertiary aromatic amines substituted with aryl groups, such as dimethylanline, P-toluidine, dibenzylamine, tribenzylamine,
β-naphthylamine, etc.; Hydrazine derivatives, such as dimethylhydrazine, diphenylhydrazine, etc.; Amide derivatives, such as carpamide, thiourea, etc.; Hydrazide derivatives, such as acetohydrazide,
Benzoyl hydrazide, phthalic acid hydrazide, etc.; Amidine derivatives, such as 1,3-diphenylguandine, di-O-tolylguanidine, etc.; Quaternary ammonium salts, such as tetraethylammonium chloride, trimethylbenzylammonium chloride, hexadecyltrimethylammonium chloride , hexyldibenzylammonium chloride, etc.; amino acid compounds such as glycine, alanine,
Cysteine, arginine, histidine, etc.; Nitrogen-containing heterocyclic compounds containing a nitrogen atom in the ring, such as pyridine, quinoline, piperidine, indole, thiazole, isidazole, acridine, pyrimidine, triazine derivatives, etc.; or the above nitrogen-containing heterocycles Examples include alkaloid compounds consisting of compounds such as quinine, thiobromine, etc. Further, as the third component used in the present invention, a compound is required that causes the coloring action of the electron-donating organic compound to disappear at a specific temperature with respect to the electron-accepting color-changing organic compound. Compounds that have this effect include alcohol,
These include esters, ethers, ketones, carboxylic acids, thiols, acid amides, sulfides, disulfides, compounds having a phenolic hydroxyl group, and specifically include the following. (1) Alcohols: Alcohols include monohydric alcohols, polyhydric alcohols, and their derivatives. Specifically, for example, n-octyl alcohol, n-nonyl alcohol, n-decyl alcohol, n-laurel alcohol, n-myristyl alcohol, n-cetyl alcohol, n-stearyl alcohol, n-icosyl alcohol, n-docosyl alcohol, n-mericyl alcohol,
Isocetyl alcohol, isostearyl alcohol, isodocosyl alcohol, oleyl alcohol, cyclohexanol, cyclopentanol, benzyl alcohol, cinnamyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, butylene glycol, hexylene These include glycol, cyclohexane-1,4-diol, trimethylolpropane, 1,2,6-hexanetriol, pentaerythritol, sorbitol, mannitol, and the like. (2) Esters: Specifically, for example, amyl acetate, octyl acetate, butyl propionate, octyl propionate, phenyl propionate, ethyl caproate, amyl caproate, ethyl caprylate, amyl caprylate, ethyl caprate, caprin. amyl acid, octyl caprate, methyl laurate, ethyl laurate, butyl laurate,
Hexyl laurate, octyl laurate, dodecyl laurate, myristyl laurate, cetyl laurate, stearyl laurate, methyl myristate, ethyl myristate, butyl myristate, hexyl myristate, octyl myristate, lauryl myristate, myristic acid myristyl, cetyl myristate, stearyl myristate, methyl palmitate,
Ethyl palmitate, butyl palmitate, hexyl palmitate, octyl palmitate,
Lauryl palmitate, myristyl palmitate, cetyl palmitate, stearyl palmitate, methyl stearate, ethyl stearate, butyl stearate, hexyl stearate, octyl stearate, lauryl stearate, myristyl stearate, cetyl stearate, stearic acid Stearyl, methyl behenate, ethyl behenate, propyl behenate, butyl behenate, ethyl benzoate, butyl benzoate, amyl benzoate, phenyl benzoate, ethyl acetoacetate, methyl oleate, butyl oleate, butyl acrylate, Diethyl oxalate, diptyl oxalate, diethyl malonate, dibutyl malonate, dibutyl tartrate, dibutyl sebatate, dimethyl sebatate, dimethyl phthalate, dibutyl phthalate, dioctyl phthalate, dibutyl fumarate, diethyl maleate, dibutyl maleate , triethyl citrate, 12-hydroxystearic acid triglyceride, castor oil, dioxystearic acid methyl ester, 12-hydroxystearic acid methyl ester, and the like. (3) Ethers; Specifically, for example, diethylene glycol dimethyl ether, diphenyl ether, distearyl ether, butyl ether, hexyl ether, diisopropyl benzyl ether, diphenyl ether, dioxane, ethylene glycol dibutyl ether, diethylene glycol dibutyl ether, ethylene glycol diethyl ether , diethylene glycol diethyl ether, ethylene glycol diphenyl ether, ethylene glycol monophenyl ether, and the like. (4) Ketones: Specifically, for example, diphenyl ketone, distyryl ketone, diethyl ketone, ethyl butyl ketone, methylhexyl ketone, medityl oxide, cyclohexanone, methylcyclohexanone, acetophenone, propiophenone, benzophenone, 2,4-pentane. These include dione, acetonylacetone, diacetone alcohol, ketone wax, etc. (5) Carboxylic acids: Carboxylic acids include monocarboxylic acids to polycarboxylic acids and their derivatives. Specifically, for example, acetic acid, propionic acid, butyric acid, caprosic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, behenic acid, crotonic acid, oleic acid, elaidic acid, linoleic acid. , linolenic acid, monochloroic acid, monobromoacetic acid, monofluoroacetic acid, glycolic acid, hydroxypropionic acid, hydroxybutyric acid, ricinoleic acid, 12-hydroxystearic acid, lactic acid, pyruvic acid, oxalic acid, malonic acid, succinic acid, adipic acid, sebatine Acid, malic acid, tartaric acid, citrusic acid, maleic acid, fumaric acid, naphthenic acid, benzoic acid, toluic acid, phenyl acetic acid, P-tert-butylbenzoic acid, cinnamic acid, chlorbenzoic acid, bromobenzoic acid, ethoxybenzoic acid , mandelic acid, protocatechuic acid, vanillic acid, resorcinic acid, dioxybenzoic acid, dioxychlorobenzoic acid, gallic acid, naphthoic acid, hydroxynaphthoic acid, phthalic acid, phthalic acid monoethyl ester, naphthalene dicarboxylic acid, naphthalene dicarboxylic acid mono These include ethyl ester, trimellitic acid, pyromellitic acid, etc. (6) Thiols: Specifically, for example, n-decylmercaptan, n-dodecylmercaptan, n-myristylmercaptan, n-cetylmercaptan, n
-stearyl mercaptan, isododecyl mercaptan, isomyristyl mercaptan, isocetyl mercaptan, dodecylbenzol mercaptan, etc. (7) Acid amides: Specifically, for example, acetamide, propionic acid amide, butyric acid amide, caproic acid amide,
Caprylic acid amide, capric acid amide, lauric acid amide, myristic acid amide, palmitic acid amide, stearic acid amide, behenic acid amide, oleic acid amide, erucic acid amide, benzamide, caproic acid anilide, caprylic acid anilide, capric acid anilide, Lauric acid anilide, myristic acid anilide, palmitic acid anilide, stearic acid anilide, behenic acid anilide, oleic acid anilide, erucic acid anilide, caproic acid anilide, caprylic acid anilide, capric acid anilide, lauric acid anilide Methylamide, myristic acid N-methylamide, palmitic acid N-methylamide, stearic acid N-methylamide, behenic acid N-methylamide, oleic acid N-methylamide, erucic acid N-methylamide, lauric acid N-ethylamide, myristic acid N-ethylamide, palmitic acid N-ethylamide,
Stearic acid N-ethylamide, oleic acid N
-ethylamide, lauric acid N-butylamide, myristic acid N-butylamide, palmitic acid N-butylamide, stearic acid N-butylamide, oleic acid N-butylamide, lauric acid N-octylamide, myristic acid N-
Octylamide, palmitic acid N-octylamide, stearic acid N-octylamide, oleic acid N-octylamide, lauric acid N-dodecylamide, myristic acid N-dodecylamide, palmitic acid N-dodecylamide, stearic acid N-dodecylamide amide, oleic acid N-dodecylamide, distearic acid amide, dipalmitic acid amide, dimyristic acid amide, dilauric acid amide, dioleic acid amide, tristearic acid amide, tripalmitic acid amide,
Trimyristic acid amide, trilauric acid amide, trioleic acid amide, succinic acid amide,
Adipic acid amide, glutaric acid amide, malonic acid amide, azelaic acid amide, maleic acid amide, succinic acid N-methylamide, adipic acid N-methylamide, glutaric acid N-methylamide, malonic acid N-methylamide, azelaic acid N-methylamide, Succinic acid N-ethylamide, adipic acid N-ethylamide, glutaric acid N-ethylamide, malonic acid N-ethylamide, azefiic acid N-ethylamide, succinic acid N-butylamide, adipic acid N-butylamide, glutaric acid N-butylamide, malonic acid N
-butylamide, adipic acid N-octylamide, adipic acid N-dodecylamide, etc. (8) Sulfides: Specifically, for example, di-n-octyl sulfide, di-n-nonyl sulfide, di-n-decyl sulfide, di-n-dodecyl sulfide, di-n-myristyl sulfide, G-n-
Cetyl sulfide, di-n-stearyl sulfide, di-tertiary dodecyl sulfide,
Octyldodecyl sulfide, diphenyl sulfide, dibenzyl sulfide, ditolyl sulfide, diethyl phenyl sulfide, 4.
These include 4'-dichlorodiphenyl sulfide, dilaurylthiodipropionate, distearylthiodipropionate, and the like. (9) Disulfides: Specifically, for example, di-n-decyl disulfide, di-n-dodecyl disulfide, di-n-
- myristyl disulfide, di-n-cetyl disulfide, di-n-stearyl disulfide, diphenyl disulfide, dibenzyl disulfide, ditolyl disulfide, dinaphthyl disulfide, 4. 4'-dichlorodiphenyl disulfide and the like. (10) Compounds having a phenolic hydroxyl group: Specifically, for example, tert-butylphenol, nonylphenol, dodecylphenol, styrene-tated phenol, 2,2'methylenebis(4-methyl-6-tert-butylphenol), α-naphthol, β-naphthol, hydroquinone monomethyl ether,
Guaiacol, eugenol, P-chlorophenol, P-bromophenol, O-chlorophenol, O-bromophenol, O-phenylphenol, P-phenylphenol, P-
(P-chlorophenyl)phenol, O-(O-
chlorophenyl) phenol, methyl P-oxybenzoate, ethyl P-oxybenzoate, P-
Propyl oxybenzoate, butyl P-oxybenzoate, octyl P-oxybenzoate, dodecyl P-oxybenzoate, 3-isopropylcatechol, P-tert-butylcatechol,
4,4'-methylene diphenyl, bisphenol A, 1,2-dioxynaphthalene, 2,3-dioxynaphthalene, chlorcatechol, bromocatechol, 2,4-dihydroxybenzophenone, phenolphthalein, O- Cresolphthalein, methyl protocatechuate, ethyl protocatechuate, propyl protocatechuate, octyl protocatechuate, dodecyl protocatechuate, 2,4,6-trioxymethylbenzene, 2,3,4 -trioxyethylbenzene, methyl gallate, ethyl gallate, propyl gallate, butyl gallate, hexyl gallate, octyl gallate, dodecyl gallate, cetyl gallate, stearyl gallate, 2,3,5-trioxynaphthalene , tannic acid, phenolic resin, etc. The coloring mechanism of the present invention will be compared with the coloring mechanism using an electron-donating color-forming organic compound that has already been proposed as follows. (A) Electron-accepting color-changing organic compound + electron-donating organic nitrogen compound (example) phenolphthalein + amine (B) Electron-donating organic compound + organic acid substance (electron-accepting substance) (Example) Crystal violet lactone + phenol From these results, it is understood that (A) and (B) are completely contradictory in terms of electron transfer involved in color change (coloring) when considering color-changing (color-forming) organic compounds. Ru. That is, the present invention takes the above color-forming system (A) and is based on the fact that a color-forming organic compound generates color by accepting electrons from a color-forming substance (or donating protons to a color-forming substance). It is. The above discoloration system (A) is the basis of the present invention, but in order to make this discoloration reversible in response to temperature changes, it is necessary to use an electron-donating organic nitrogen for an electron-accepting discolored organic compound. The presence of a compound that causes the color-changing effect of the compound to expire at a specific temperature is essential. That is, the color changes at a temperature where no effect occurs, but it does not change color at a temperature where an effect occurs. According to the research conducted by the present inventors, the compound constituting the third component generally has no negative effect at low temperatures, that is, when it is solid, and that increasing the temperature does not affect the melting point of the compound. Many of them show positive effects. Furthermore, the term "discoloration" referred to here differs depending on the electron-accepting discoloration organic compound used, and can be broadly classified as follows. (Low temperature) (High temperature) Colored Colorless Colored Light color (Including cases with hue difference) Colored Colored (Hue difference) In this case, it means the case where dyes and pigments that do not change color are not added.) When preparing the temperature-indicating material of the present invention, the proportion of each component is 1 part (by weight, (the same applies hereinafter), 0.1 to 100 parts of an electron-donating organic nitrogen compound (B), and a third component (C)
It is desirable to use 10 to 1000 parts. In particular, the ratio of component (B) varies depending on the combination of each component; if it is too large, the color will be discolored from beginning to end, and if it is too small, the color will not change from beginning to end. The above three components are essential components of the present invention, and basically a sufficient effect can be obtained with one type of compound of each component, but a wider range of effects can be obtained by mixing two or more of each component. . For example, creating a color mixture using two or more electron-accepting color-changing compounds,
The discoloration temperature can be adjusted by using two or more of the components (A). Furthermore, by adding non-discoloring dyes and pigments other than the three components, it is possible to obtain a colored change (with a hue difference), and furthermore, as long as it does not have an adverse effect on the temperature-indicating material of the present invention, a plasticizer can be added. ,
Ultraviolet absorbers, thickeners, leveling agents, etc. can be added. Next, the temperature-indicating material according to the present invention can be obtained, for example, by mixing the above three components and heating and melting all the components. Temperature-indicating materials consisting of the three components generally exhibit a phase change from solid to liquid, and when heated, they become liquid and the composition ratio of the three components changes, making them extremely difficult to handle. be. Therefore, it is necessary to maintain the appearance of a solid even at high temperatures. For this purpose, the temperature-indicating material of the present invention may be sealed and fixed in an ink or paint binder, or may be encapsulated in microcapsules. Furthermore, it is desirable to incorporate the microcapsules obtained in this manner into a molded polymer. Microencapsulation techniques include the selection of wall material from among known techniques such as air suspension method, spray granulation method, pan coating method, interfacial polymerization method, in situ polymerization method, and coacervation method. It can be selected as appropriate depending on the purpose. The temperature-indicating material of the present invention obtained as described above can be sealed in a transparent container, printed or coated on various supports as ink or paint, or formed into various molded products such as films, chips, and blocks. It can be applied to various fields. For example, temperature detection by color in various industries, temperature detection especially in low-temperature industries, monitoring of temperature changes in chemical reactions, etc., disaster prevention by color change temperature indication of hazardous materials containers or storage areas, temperature distribution measurement of chemical machines, etc., electrical circuits. Temperature indicators for early detection of heat generation due to overloading of electrical equipment, temperature indicators for household refrigerators, frozen foods, air conditioners, various heaters, baths, etc.
Applications include anti-tamper printing for various books, cash coupons, gift certificates, horse racing tickets, admission tickets, etc., displays, advertising media, educational materials, toys, etc. EXAMPLES Below, Examples and Comparative Examples of the present invention will be shown and explained in more detail. In the following examples, each sample was heated and melted in a test tube, spread on paper and cooled, and the discoloration temperature and color change were measured and observed using a micromelting point measuring device. In all examples, the numbers in parentheses after each compound indicate parts by weight. In addition, for Examples 1 to 21 shown in Table 1, variations in color change depending on the type of (A) electron-accepting color-changing organic compound were mainly investigated, and the color change temperature was 50 to 60°C in all cases.
within the range of Examples 22 to 53 shown in Table 2 mainly list the types of electron-donating organic nitrogen compounds (B), and the color change and color change temperature are all the same (generally red and colorless at 50 to 60°C). Also, Table 3
In Examples 54 to 72 shown in , the variation in color change temperature depending on the type of the third component (C) was mainly studied, and the color changes were all the same (generally red and colorless). Examples 1 to 21

【table】

【table】 Examples 22-53

【table】

【table】 Examples 54-72

【table】

[Table] Examples 73 to 75, Comparative Examples 1 to 3 For comparison, temperature-indicating materials (Comparative Examples 1 to 3) using coloring systems (combinations of electron-donating color-forming organic compounds and acidic substances) that conflict with the present invention, A light resistance test was conducted on the temperature indicating materials according to the present invention (Examples 73 to 75).

【table】

[Table] As a result of spreading each temperature-indicating material with the above composition on paper and exposing it to sunlight outdoors for about 24 hours, all of the samples of Comparative Examples 1 to 3 had fading or decreased discoloration function, but the present invention Example 73~
All 75 samples were in good condition.

Claims (1)

[Scope of Claims] 1 (A) an electron-accepting color-changing organic compound consisting of phthaleins or fluoresceins and their derivatives, (B) an organic nitrogen compound exhibiting electron-donating properties to the compound (A), and ( C) A reversible temperature-indicating material comprising a compound that causes the discoloration effect of compound (B) on compound (A) to disappear at a specific temperature. 2. The reversibility of item 1 above, wherein the compound (C) is at least one selected from the group consisting of alcohols, esters, ethers, ketones, carboxylic acids, thiols, acid amides, sulfides, disulfides, and compounds having a phenolic hydroxyl group. Temperature indicating material.