JPH09257596A - Instant food indicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily and inexpensively display a taste guarantee term of instant noodles by polymerizing oxidizing polymerizing pigment by contacting two layers respectively containing a chemical agent by combining oxidizing polymerizing pigment and an oxidizing agent with each other, and revealing a temperature-time integrated value as a color change. SOLUTION: Oxidizing polymerizing pigment is a chemical material to reveal a prescribed hue in a prescribed polymerization degree by starting polymerization reaction of pigment by reacting by contacting with an oxidizing agent, and aniline, pyrrole, carbazole and a derivative of these or the like can be cited, and these may be used independently or by mixing two together. Metallic salt and the like, oxygen acid salt, halogen, quinine and the like can be cited as the oxidizing agent. A type of using them by sticking them together at use time by individually separating them from each other until two layers are used, a type of reacting them by dispersing both agents by a trigger at use time by arranging another one layer between the two layers or the like, can be cited as method of contacting the two layers containing a chemical agent by combining the oxidizing polymerizing pigment and the oxidizing agent with each other.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an instant food indicator that displays a time or temperature-time integrated value as a color change by polymerizing an oxidatively polymerizable dye, and pouring hot water by attaching the indicator. The present invention relates to an instant food packaging container that has a function of easily and easily sensing the optimal season for cooked instant noodles and cooked rice that are left for a few minutes.

[0002]

2. Description of the Related Art Currently, although it is known that chemical materials can display the storage temperature of articles when they are managed for a certain period of time under a certain environment, materials that can display their storage time chemically are available on the market. I don't see you. For this reason, it was not possible to easily detect the optimum shelf life of instant noodles and cooked rice, which are poured into hot water and left for a few minutes to serve as a post-meal.

Conventionally, as a material for displaying a temperature / time history by a color change, Patel using a diacetylene-based compound which displays a range of several tens of hours at a temperature of about 100 ° C. by changing from pink to metallic green, etc. US Pat. No. 4,189,399 (issued 1980.2.19), US Pat. No. 4,208,186 (issued 1980.6.17), US Pat. No. 4,276,190 (issued 1980.6.30), about room temperature U.S. Pat. No. 4,212,153, issued to Kiddonius et al. (Published on 1980.7.15) using a dye which develops a colorless to purple color in the range of several tens of days and diffusion of an acid or alkali, a redox dye and oxygen diffusivity. U.S. Pat.
768,976, U.S. Pat. No. 3,966,414 to Cartab et al., Which uses a composition of a free radical-sensitive dye and a peroxide, which is indicated by the fading of green, and a triarylmethane dye decolorized with a reducing agent. Japanese Patent Application Laid-Open No. Sho 62-62, such as Buhatta Charge, which utilizes coloring by diffusion of oxygen.
And JP-A-5-61917 by Matsuda et al. Using an acid-producing microorganism and a pH indicator. In addition, patents utilizing melting points, diffusion rates, enzyme activities, and the like have been disclosed.

[0004] Although various display materials have been proposed but not actually put on the market, they are inconvenient to handle in a solution state, and the method of starting time measurement is complicated or unclear. Or the price is high. For example, the invention of Cartab et al. (US Pat. No. 3,966,414) using a composition of a free radical-sensitive dye and a peroxide is intended to support a dye and a peroxide on glass fiber paper as a display material. Then, a dye and a peroxide are dissolved in a solvent, and the solution is spread on glass fiber paper. Here, from the viewpoint of time measurement,
The reaction has started when the dye and peroxide are dissolved,
There is a disadvantage that it is not practically suitable for time measurement at a temperature lower than room temperature. In addition, most of the color changes seen in the conventional technologies are those in which a certain color develops from transparent and its color density increases, and those in which the other hue fades to become transparent and clear. No color changing material was found.

[0005]

SUMMARY OF THE INVENTION According to the present invention, hot water can be displayed by using a chemical time indicator that can easily and inexpensively display that a predetermined time has passed at a predetermined temperature by a clear change in hue. This makes it possible to easily detect the optimal season for instant noodles and cooked rice to be served after pouring for a few minutes.

[0006]

Means for Solving the Problems The present inventors have found that a color change occurs depending on the degree of polymerization, which is composed of an oxidatively polymerizable dye and an oxidant, and the polymerization rate is the same as in a normal chemical reaction. Since the temperature and time are defined by the Arrhenius law, it was found that the temperature-time integrated value, which should be called the total of the time change and the calorific value at a predetermined temperature, can be displayed as a color change. By sticking this indicator to the instant food, it became possible to easily sense the optimum season for instant noodles and cooked rice to be poured into hot water and allowed to stand for a certain period of time for subsequent eating.

The present invention comprises a layer containing the following agent A supported on a carrier and a layer containing the following agent B which is in a non-contact state with the agent A. The present invention relates to an instant food indicator that displays a time or temperature-time integrated value as a color change by polymerizing a dye (provided that the agent A and the agent B are a combination of an oxidative polymerizable pigment and an oxidant). Furthermore, the present invention relates to an instant food packaging container to which the above indicator is attached.

BEST MODE FOR CARRYING OUT THE INVENTION

The oxidatively polymerizable dye used in the present invention is a compound which reacts when brought into contact with an oxidizing agent to initiate the polymerization reaction of the dye and polymerize to develop a predetermined hue at a predetermined degree of polymerization, and polymerize. The front may be colorless or colored. This polymerization reaction is similar to a normal chemical reaction,
The reaction rate is defined by the difference in temperature. Furthermore, the oxidatively polymerizable dye in the present invention is a dye whose hue or color density changes depending on the degree of polymerization, and the hue is defined by temperature and time. That is, since the polymerization rate follows the Arrhenius rule, the degree of polymerization of the dye is defined as a function of the absolute temperature and time, and as a result, the time or the integrated value of temperature-time can be displayed as a color change.

The amount of heat obtained at a constant temperature or a fluctuating temperature can be expressed as an integrated value obtained by the product of the temperature at each time and its time. The integrated value of this temperature and time is the temperature-time integrated value. It is defined as For example, refrigerated food such as meat and fish is 20 hours at 30 ° C for 12 hours.
The shelf life or expiration date changes depending on the storage temperature, such as 24 hours at C and 72 hours at 10 ° C. When considering the actual distribution of products, the storage temperature can be considered to be constantly fluctuating though varying in degree.
The problem here is "how many temperatures have been left or stored at what temperature", and this scale is called the temperature-time integrated value. However, temperature 20 ° C
The problem that the deterioration or change in one hour is equivalent to how many hours change at a temperature of 10 ° C. is represented by a simple product of absolute temperature and time because it is defined by the frequency factor and the activation energy in the Arrhenius law. Not something.

The color development in the present invention is caused by the polymerization of the oxidatively polymerizable dye, and the hue changes depending on the degree of polymerization of the resulting polymer, and is considered to be due to the following mechanism by taking 2-methoxy-phenothiazine as an example. To be The hydrogen atom bonded to the nitrogen atom in the molecule is abstracted by the oxidizing agent to start the polymerization, and further, any of the 1, 3, 4, 6, 7, 8, and 9-positions in the 2-methoxy-phenothiazine molecule. Hydrogen atom of is extracted. It is inferred that this molecule and a 2-methoxy-phenothiazine molecule in a similar state adjacent to each other proceed with polymerization by using the carbon atom from which the 10th-position nitrogen atom and the hydrogen atom have been removed as a binding site. Tert- of Example 1
FIG. 1 shows a mass spectrum of 2-methoxy-phenothiazine polymerized with butylperoxybenzoate as an oxidizing agent at the initial stage of polymerization. Although the details of the reaction mechanism are not clear, it is clear from FIG. 1 that 2-methoxy-phenothiazine is polymerized by the reaction of the oxidizing agent and 2-methoxy-phenothiazine. It is considered that the hue changes because the conjugated system changes as the polymerization of 2-methoxy-phenothiazine proceeds. That is,
It is expected that as the degree of polymerization increases, the wavelength becomes longer and the color changes from green to reddish brown.

Regarding the relationship between the hue of 2-methoxy-phenothiazine, the degree of polymerization and the distribution thereof, the degree of polymerization 2 is green, the degree of polymerization 3 is blue, and the degree of polymerization is 4 from the hue and the molecular weight from the mass spectrometer. It became clear that it became reddish brown at 10. It is also presumed that navy or purple color is formed depending on the ratio of the polymers having different polymerization degrees. Regarding the other phenothiazine derivatives and phenoxazine derivatives, the electronic state of the conjugated system was significantly different depending on the kind of the substituent bonded to the phenothiazine skeleton, and different hue changes were observed depending on the substituents. In any case, the hue to be developed is determined by the degree of polymerization of the phenothiazine derivative and the phenoxazine derivative and its distribution, and the color tone changes with the progress of polymerization. The structure of the 2-methoxy-phenothiazine molecule referred to herein and the positions of the constituent atoms follow the formula below.

[0012]

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The oxidatively polymerizable dye used in the present invention is not limited as long as it is oxidatively polymerized and exhibits a predetermined hue at a predetermined degree of polymerization. Specifically, the oxidatively polymerizable dye referred to herein refers to a dye that is oxidatively polymerized by an oxidizing agent represented by a metal salt or the like and exhibits a predetermined hue at a predetermined degree of polymerization, and even if it is colorless before polymerization. It is defined as an oxidatively polymerizable dye. More specifically, the oxidatively polymerizable dyes include benzene derivatives such as aniline, phenol, thiophenol and their derivatives, 5-membered aromatic heterocyclic compounds such as pyrrole, thiophene, furan, selenophene, tellurophene and their derivatives, and carbazole. In addition to condensed 6,5,6-membered aromatic heterocyclic compounds such as dibenzothiophene and their derivatives, compounds represented by the following formulas can be mentioned.

[0014]

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Wherein R1 to R7 are hydrogen, halogen, alkyl having 1 to 8 carbon atoms, alkoxy having 1 to 8 carbon atoms, aryl, substituted aryl, heterocyclic aryl, hydroxyl, amino, Cyano, aldehyde,
X represents an atom and an atomic group selected from carboxyl, nitro, and nitroso, and adjacent substituents may further form an aromatic ring together, and X represents an atom selected from sulfur, oxygen, selenium, and tellurium. In addition, the binding site is R1
R4 is selected from the 1st, 2nd, 3rd and 4th positions in the formula, respectively, and two or more R1 to R4
Substituents selected from are not bonded, but one at each position. Similarly, for R5 to R7, three positions are selected from the 6-position, 7-position, 8-position and 9-position in the formula, respectively, and a substituent selected from two or more R5 to R7 is bonded to one position. It will never be linked, one at each of the three chosen positions. In addition to the above, R1
As to R7, any substituent can be used as long as it does not hinder polymerization.

More specifically, phenothiazine, 3,7-
Dibromophenothiazine, 2-chlorophenothiazine,
4-methylphenothiazine, 3,7-dimethylphenothiazine, 4,6-dimethylphenothiazine, 2-acetylphenothiazine, 3-vinylphenothiazine, 3,7
-Diamino-phenothiazine, 3,7-bis- (dimethylamino) -phenothiazine, 3,7-bis- (diethylamino) -phenothiazine, 2-hydroxy-phenothiazine, 3-formyl-phenothiazine, 3-carboxyl-phenothiazine, 3, In addition to 7-dimethoxy-phenothiazine, 1-nitro-phenothiazine, 1,3-dinitro-phenothiazine, 4-chloro-1-nitro-phenothiazine and the like, JP-A-3-144650.
Monobenzo-phenothiazine which forms an aromatic group together with two members selected from R1 to R4 as disclosed in
Similarly, benzophenothiazines such as dibenzo-phenothiazine, which forms an aromatic group together with two members selected from R5 to R7 in addition thereto.

Further, similar to the phenothiazine derivative, phenoxazine derivatives such as 3,7-dibromophenoxazine are also mentioned as the oxidation-polymerizable dye. The synthesis of these phenothiazines and phenoxazines is described in Asakura Publishing Co., Ltd.
Heterocyclic compound IV It can be carried out by the method described on pages 33 and 17 and the like.

The oxidatively polymerizable dyes used in the present invention may be used alone or in a mixture of two. In this case, the hue can be changed depending on the mixing ratio. The oxidatively polymerizable dye is added in an amount of 1.0 to 20% by weight, preferably 2.0 to 15.0% by weight, relative to the medium forming the carrier to obtain the time indicating material of the present invention.
At this time, if the blending amount of the oxidatively polymerizable dye is 1.0% by weight or less, coloration is thin and visibility is poor. In addition, although the degree of color development does not change so much even if the blending amount is 20% by weight or more,
During storage of the display material, the color develops due to air oxidation,
It may not be suitable for use.

In the present invention, the oxidizing agent for polymerizing the oxidatively polymerizable dye includes metal salts, oxyacid salts, halogens, quinones, naphthoquinones, carbonyl compounds, oxides, organic peroxides, organic peracids, and peroxosulfuric acid. Examples thereof include salts and nitro compounds. More specifically, metal salts include aluminum chloride, nickel chloride, cobalt chloride, copper chloride, iron chloride, vanadium chloride and the like. Examples of oxyacid salts include nitric acid, chlorate, hypochlorite, iodate, bromate, chromate, permanganate, vanadate, bismuthate and the like. Examples of the halogen include fluorine, chlorine, bromine, and iodine. The quinones include benzoquinone, tetrachloro-1,4-benzoquinone (chloranil), tetrachloro-1,2-benzoquinone (o-chloranyl),
2,3-dichloro-5,6-dicyano-1,4-benzoquinone and the like. The naphthoquinones include 1,2-naphthoquinone, 1,4-naphthoquinone, 2,6-naphthoquinone,
1,2-naphthoquinone-4-sulfonic acid and the like. Examples of the carbonyl compound include acetone and cyclohexanone, which are used in combination with an aluminum alkoxide such as aluminum butoxide. Examples of oxides include manganese dioxide, lead dioxide, copper oxide, silver oxide and the like.

The organic peroxides include dialkyl peroxides such as di-tert-butyl peroxide, tert-butyl cumyl peroxide and dicumyl peroxide, and diacyl such as acetyl peroxide, lauroyl peroxide and benzoyl peroxide. Peroxides such as peroxides, methyl ethyl ketone peroxide, cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methyl cyclohexanone peroxide, etc., 1,1-bis (tert-butylperoxy) cyclohexane, etc. Ketals, tert-butyl hydroperoxide, cumene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, p-medium Hydroperoxides such as tanhydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, tert-butylperoxyacetate, tert-butylperoxy-2-ethylhexano There are peroxyesters such as oleate and tert-butylperoxybenzoate. Among them, benzoyl peroxide has a good balance between the oxidizing ability and the storage stability, and is suitable as an organic peroxide oxidant. . Examples of the organic peracid include perbenzoic acid, metachloroperbenzoic acid, monoperoxyphthalic acid, formic acid, peracetic acid, and trifluoroperacetic acid. Examples of the peroxosulfate include peroxodisulfuric acid and potassium peroxodisulfate. Examples of the nitro compound include nitrobenzene and nitrocellulose. In addition, oxygen, ozone, chlorine, bromine, iodine, sulfur, aqua regia,
Nitric acid, concentrated sulfuric acid, hot concentrated perchloric acid, dimethyl sulfoxide and the like are mentioned as the oxidizing agent in the present invention. In addition,
Use of a biochemical oxidizing agent using a dehydrogenase such as dehydrogenase as the oxidizing agent of the present invention does not impose any restrictions.

The carrier in the present invention is one which is capable of diffusing A agent and B agent, that is, a polymerizable dye and an initiator at a predetermined temperature and maintaining its shape, and is transparent enough to recognize a color change. There is no limitation on the use of any material as long as it has the property. Specifically, acrylic resins, polyester resins, polyether resins, polyurethane resins, silicone resins, epoxy resins, vinyl resins, etc., resins used as binders for ordinary inks and paints, and adhesives used as general adhesives Any resin may be used as long as it is a rubber-based resin, or a mixture of several types of the above resins, or a ketone-based, ether-based, alcohol-based, cellosolve-based, petroleum-based, or water-based solvent that is not diluted with a commonly used solvent. You may. Particularly, the adhesive rubber-based resin is advantageous in that it exhibits an adhesive function when the carrier and the transparent substrate are brought into contact with each other.

Specifically, the tacky rubber-based resin is a resin having Tg of room temperature or lower, preferably -10 ° C. or lower, and it is desirable that it is a rubber-like region in the temperature range during use. Examples include tacky acrylic resins, natural and synthetic cis-
1,4-polyisoprene rubber, butyl rubber, halogenated butyl rubber, partially vulcanized butyl rubber, styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SI
S), styrene-ethylene-butylene-styrene block copolymer (SEBS), silicone rubber, chloroprene rubber, nitrile rubber, butadiene rubber, and the like, which are used as the resin for adhesives.

In particular, the tacky acrylic resin can have its composition and molecular weight appropriately set to freely change the Tg, and can control the diffusion speed of the agent A or agent B. It is suitable as a medium for the agent and the agent B. Adhesive acrylic resin is a hydroxyl group, tertiary amino group,
It has a functional group such as a carboxyl group, an amide group, and a nitrile group, and is generally used as an acrylic resin for pressure-sensitive adhesives. The acrylic resin having these functional groups includes one or several kinds of monomers having a hydroxyl group, a tertiary amino group, a carboxyl group, an amide group, a nitrile group, an alkyl (meth) acrylate,
Examples thereof include copolymers with monomers such as vinyl acetate, vinyl propionate, vinyl ether and styrene.

The reaction is an ordinary radical polymerization, and there is no limitation on the reaction method, and it can be carried out by a known polymerization method such as solution polymerization, bulk polymerization, emulsion polymerization, etc., but it is easy to control the reaction. Solution polymerization is preferred because it can be directly transferred to the next operation. The solvent may be any solvent, such as methyl ethyl ketone, methyl isobutyl ketone, toluene, cellosolve, ethyl acetate, and butyl acetate, as long as it dissolves the resin of the present invention. A single solvent or a mixture of a plurality of solvents may be used. Further, the polymerization initiator used in the polymerization reaction is also known such as benzoyl peroxide, acetyl peroxide, methyl ethyl ketone peroxide, organic peroxides such as lauroyl peroxide, and azo initiators such as azobisisobutyronitrile. Anything can be used, and there is no particular limitation.

The adhesive rubber resin is partially cross-linked with a cross-linking agent such as a metal chelate, an isocyanate and an epoxy compound to improve the adhesive property at the time of contact of the carrier and to enhance the cohesive force, the agent A or the The diffusion rate of the B agent can be adjusted. In addition, polyurethane resin,
It has good printability such as gravure printing, and is one of the preferred materials for the carrier from the viewpoint of productivity of the display material. As such a polyurethane resin, Toyo Ink Manufacturing Co., Ltd.
Examples of the urethane resin for gravure ink manufactured include "Lamister R Medium", "New LP Super", "LP Queen" and the like.

To the carrier in the present invention, pigments, dyes, inorganic fillers, metal powders such as silver powder, copper powder, nickel powder, carbon black, graphite, xylene resin, rosin resin, etc. may be attached to the carrier as required. Agents, silane coupling agents, defoaming agents, leveling agents, plasticizers such as dibutyl phthalate and dioctyl phthalate, and the like can be added. In particular, when an inorganic filler such as Aerosil, titanium dioxide, or barium sulfate is added, the cohesive force of the carrier is improved, the tack on the surface of the carrier is reduced, and the agent A or the agent B, that is, the oxidative polymerizable dye or the oxidant is added. The effect of suppressing the diffusion rate by adsorption or the like is exerted, and the effect of expanding the range of temperature-time integrated value measurement can be provided.

In the present invention, the carrier may be laminated on the transparent substrate. Such transparent substrates include olefin films such as polyethylene and polypropylene, polyester films represented by polyethylene terephthalate, polyethylene terephthalate, etc., cellophane, polyvinylidene chloride copolymer, polyvinylidene chloride copolymer, polyvinylidene fluoride, polyvinyl chloride. Examples thereof include plastic films such as vinyl, nylon, polyacrylic acid and polymethacrylic acid. In addition, any material may be used as long as the material has transparency enough to confirm a change in hue.

In the present invention, the carrier may be a printed layer. Such a printing layer is a layer using a resin printed by silk screen printing, gravure printing, offset printing, etc. as a medium, and regarding the printing style and the binder resin used, if it is a resin layer that can be formed by printing However, there is no restriction whatsoever what is used.

In the present invention, the method of bringing the agent A and the agent B into a non-contact state is a type in which the layer containing the agent A and the layer containing the agent B are separately separated until they are used, and they are pasted at the time of use. Another layer is provided between the layer containing the agent A and the layer containing the agent B, and a multi-layer type in which the agent A and the agent B are diffused and reacted by a trigger at the time of use, the agent A or the agent B is a microcapsule. Examples thereof include a type in which the capsules are broken into pieces and separated, and the capsules are destroyed by applying pressure when used.

The indicator can be used by sticking it to the central portion or the peripheral portion of the surface of the upper lid of the instant food, or sticking it to the side surface of the container. Also, some instant foods have a bar code label that is used to fix the lid after breaking the outer wrap and pouring hot water, but it can also be attached to one end of this label. is there. At this time, depending on the material of the instant food packaging container, the position where it is pasted, and the like, the temperature at which the hot water is heated varies, and the configuration of the indicator, the component ratio, and the like change.

In the present invention, the instant food is specifically, instant ramen in a cup container, instant udon in a cup container, instant soba in a cup container, instant yakisoba in a cup container, instant spaghetti in a cup container, instant fried rice in a cup container. , Instant porridge in cups, instant soup in cups, and other instant foods in cups. In addition, among instant noodles in a bag-shaped package called commonly called bag noodles, there are those that can be cooked simply by pouring boiling water, and even for such foods, the material of the present invention is stuck to a container. It is possible to use.

[0032]

The present invention will be described below with reference to examples. In the examples, “parts” means “parts by weight” and “%” means “% by weight”.

Resin 1 Butyl acrylate 94.1 parts Acrylic acid 5.9 parts Azobisisobutyronitrile 0.2 parts Ethyl acetate 150.0 parts Each of the above was heated to 80 ° C. in a nitrogen atmosphere using a flask as a reaction vessel. To 125 parts of the mixture of the composition, 125 parts of the above mixture of the same composition is added dropwise. After the completion of the addition, the mixture is heated to reflux for 12 hours, cooled, and a solution of resin 1 (solid content 40%).
I got

Example 1 100 parts of a solution of Resin 1 and 12 parts of a 10% ethyl acetate solution of 2-methoxyphenothiazine were mixed with stirring to obtain PE.
It was coated on a T film and dried by heating at 90 ° C. for 2 minutes to form a first layer having a film thickness of 25 μm. Further, 100 parts of a solution of Resin 1, 5 parts of a 40% ethyl acetate solution of tert-butylperoxybenzoate, and 16 parts of Aerosil 200 (silicon dioxide fine particles manufactured by Nippon Aerosil Co., Ltd.) were mixed by stirring to form a PET film. Apply and heat dry at 90 ° C for 2 minutes to form a second layer with a film thickness of 25 microns.
It was attached to the first layer on the previously coated PET, and the pressure-sensitive adhesive layer was further coated on one PET surface. As a result, PET
A label consisting of two layers of film / first layer and second layer / P
A B label having three layers of ET film / adhesive layer was obtained. At the time of use, the first layer of the A label and the second layer of the B label were bonded together, and this display material was further bonded to the central portion of the lid of the instant cup noodle with the adhesive layer of the B label. After peeling off the lid of the cup and pouring boiling water on the cup noodles,
The lid was closed again and the color change of the display material was observed. as a result,
After 10 seconds from the pouring of hot water, the color developed green, the color changed to blue after 1 minute, the color changed to blue-purple after 2 minutes, the color changed to dark reddish brown after 3 minutes, and the color did not change thereafter.

Example 2 100 parts of a solution of Resin 1 and 12 parts of a 10% ethyl acetate solution of 2-methoxyphenothiazine were mixed with stirring to obtain PE.
It was coated on a T film and dried by heating at 90 ° C. for 2 minutes to form a first layer having a film thickness of 25 μm. Further, 100 parts of a resin 1 solution, 10 parts of a 40% ethyl acetate solution of tert-butyl peroxybenzoate, Aerosil 200
(Nippon Aerosil Co., Ltd. silicon dioxide fine particles) 1
6 parts by stirring and mixing are applied on a PET film, and 90
It was heated and dried at 0 ° C. for 2 minutes to form a second layer having a film thickness of 25 μm. Furthermore, on the surface of the second layer, carnauba wax 20
% Toluene solution was applied and heated and dried at 90 ° C. for 2 minutes to form an isolation layer having a film thickness of 5 μm. After pasting the first layer on the previously coated PET and this isolation layer / second layer / PET,
Further, an adhesive layer was coated on one PET surface. As a result, PET film / first layer / isolation layer / second layer / PET
A time display material for instant cup noodles comprising 6 layers of film / adhesive layer was obtained. This display material was attached to the central portion of the instant cup noodle lid. After removing the lid of the cup and pouring boiling water onto the cup noodles, the lid was closed again and the color change of the display material was observed. As a result, 10 seconds after pouring hot water, the green color was formed, the blue color changed 1 minute later, the blue color changed 2 minutes later, the dark reddish brown color changed 3 minutes later, and the color did not change thereafter.

Example 3 100 parts of a solution of Resin 1 and 12 parts of a 10% ethyl acetate solution of phenothiazine were mixed by stirring, coated on a PET film, and dried by heating at 90 ° C. for 2 minutes to give a film thickness of 25 μm. Was the first layer. Nitrocellulose HIG2
100 parts of a 30% ethyl acetate solution of 00 (Nitani Cotton manufactured by Asahi Kasei Co., Ltd.) and 30 parts of dibutyl phthalate are mixed by stirring and applied on a PET film, and dried by heating at 90 ° C. for 2 minutes to give a film thickness of 25. It was the second layer of micron. Furthermore, a 20% toluene solution of carnauba wax is applied to the surface of the second layer and dried by heating at 90 ° C. for 2 minutes to give a film thickness of 5 μm.
The isolation layer. After bonding the first layer on the previously coated PET and this isolation layer / second layer / PET, an adhesive layer was further coated on one PET surface. As a result, a time display material for instant cup noodles comprising 6 layers of PET film / first layer / isolation layer / second layer / PET film / adhesive layer was obtained. This display material was attached to the central portion of the instant cup noodle lid. After removing the lid of the cup and pouring boiling water onto the cup noodles, the lid was closed again and the color change of the display material was observed. As a result, 2 minutes after pouring hot water, the color slightly changed to green, and 3 minutes later, it became a deep emerald green and did not change color thereafter.

Example 4 100 parts of a solution of Resin 1 and 12 parts of a 10% ethyl acetate solution of phenothiazine were mixed by stirring and coated on a PET film, and dried by heating at 90 ° C. for 2 minutes to give a film thickness of 25 μm. Was the first layer. Further, 100 parts of the resin 1 solution,
A 40% xylene solution of benzoyl peroxide was mixed with 6 parts by stirring, and the mixture was applied onto a PET film and dried by heating at 90 ° C. for 2 minutes to form a second layer having a thickness of 25 μm. On the surface of the second layer, 20% of carnauba wax
A toluene solution was applied and heated and dried at 90 ° C. for 2 minutes to form an isolation layer having a film thickness of 5 μm. First on PET that was previously coated
After adhering the layer and this isolation layer / second layer / PET, a pressure-sensitive adhesive layer was further applied on one PET surface. As a result,
A time display material for instant cup noodles having 6 layers of PET film / first layer / isolation layer / second layer / PET film / adhesive layer was obtained. This display material was attached to the central portion of the instant cup noodle lid. After removing the lid of the cup and pouring boiling water onto the cup noodles, the lid was closed again and the color change of the display material was observed. As a result, 5 seconds after pouring hot water, the color develops green, 30 seconds later it becomes blue, and then 4
After 5 seconds, the color changed to blue-purple, and after 1 minute, the color became dark red, and the color did not change thereafter.

Example 5 100 parts of a solution of Resin 1 and 12 parts of a 10% ethyl acetate solution of 3,7-dioctylphenothiazine were mixed by stirring and coated on a PET film, and dried by heating at 90 ° C. for 2 minutes. The first layer having a film thickness of 25 μm was used. Further resin 1
Solution of 100 parts, 10 parts of a 40% ethyl acetate solution of tert-butyl peroxybenzoate, Aerosil 2
00 (Silicon dioxide fine particles manufactured by Nippon Aerosil Co., Ltd.)
And 16 parts of the mixture are mixed by stirring and coated on a PET film,
Heat dried at 90 ° C for 2 minutes and the film thickness is 25 microns.
As a layer, and laminated with the first layer on the previously coated PET,
Further, an adhesive layer was coated on one PET surface. As a result, an A label consisting of two layers of PET film / first layer and a B label consisting of three layers of second layer / PET film / adhesive layer were obtained. At the time of use, the first layer of the A label and the second layer of the B label were bonded together, and this display material was further bonded to the center portion of the side surface of the instant cup noodle with the adhesive layer of the B label. After removing the lid of the cup and pouring boiling water onto the cup noodles, the lid was closed again and the color change of the display material was observed. As a result, 3 minutes after pouring hot water, a green color was formed, and then the color changed to blue.

EFFECTS OF THE INVENTION The time display material of the present invention makes it possible to easily and inexpensively display the time when an instant cup noodle is eaten by a clear change in hue.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomio Muto 2-3-13 Kyobashi, Chuo-ku, Tokyo Toyo Inki Manufacturing Co., Ltd. (72) Keisuke Kaiho 2-3-3 Kyobashi, Chuo-ku, Tokyo No. Toyo Inki Manufacturing Co., Ltd.

Claims (2)

[Claims] 1. A layer comprising a layer containing the following agent A supported on a carrier and a layer containing the following agent B which is in a non-contact state with the agent A. Instant food indicator that displays time or temperature-time integrated value as color change by polymerization (however,
Agent A and agent B are a combination of an oxidatively polymerizable dye and an oxidant. ). 2. An instant food packaging container to which the indicator according to claim 1 is attached.