JP2017166879A - Temperature history display medium, manufacturing method thereof, and use method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a temperature history display medium which can be stored at normal temperature and is simply operable with discretionary timing.SOLUTION: A temperature detector pertaining the present invention comprises a base material, a color development layer including a color former, a temperature sensitive layer including a developer for prompting color development or discoloration of the color former and a temperature sensing agent that dissolves when a prescribed temperature is exceeded, and a diffusion prevention layer for preventing the diffusion of the developer to the color development layer and arranged between the color development layer and the temperature sensitive layer. The temperature sensitive layer, the diffusion prevention layer, and the color development layer are laminated on the base material in the order stated, the side face of the temperature sensitive layer being covered with a nonporous member, the diffusion prevention layer being fixed to the nonporous member by an adhesive that peels off at a prescribed temperature or below.SELECTED DRAWING: Figure 2

Description

The present invention relates to a temperature history display body that irreversibly displays a temperature history, a manufacturing method thereof, and a usage method thereof.

  Various low temperature storage temperatures such as refrigeration or chilled refrigeration are used in merchandise logistics such as pharmaceuticals and foods. If the proper management temperature is deviated when transporting or storing a physical distribution, there will be a decrease in medicinal effect in the case of pharmaceuticals, deterioration of flavor, deterioration such as spoilage, and breeding problems of bacteria in the case of foods. Therefore, there is a need for a technique that can display a temperature history when the temperature deviates from an appropriate management temperature.

  In order to solve this problem, thermochromic markings (temperature history display bodies) that cause irreversible changes when deviating from the management temperature have been studied. The color does not develop when the storage temperature of the product is lower than the set temperature, but the color develops when the temperature exceeds the set temperature, and the color remains developed even after cooling again. If a product deviates from the proper management temperature, its history remains. By using this temperature history display body, it is possible to grasp whether the temperature is managed at an appropriate temperature.

  Further, the temperature history display body is required to be stored at room temperature. If storage at room temperature is not possible, the temperature history display must be kept below the set temperature until the user attaches it to the product to be measured after the temperature history display is manufactured. Therefore, the temperature management of the temperature history display body becomes complicated.

  Patent Document 1 discloses a temperature history including a temperature detecting layer containing a higher fatty acid metal salt that liquefies below a specific temperature, a color former layer, and a developer layer containing a developer and a heat melting component. A display is disclosed. When placed in an environment below the critical temperature of the higher fatty acid metal salt, the temperature detecting layer is dissolved, and the developer layer and the color former layer are easily brought into contact with each other (“switch-on” state). In this state, when the temperature history display body is placed above the melting temperature of the hot-melt component in the developer layer, the hot-melt component containing the developer flows and comes into contact with and reacts with the color developing layer. It is described that color develops.

  In Patent Document 2, an ink-penetrating sheet adheres to a base sheet on which an indicator ink layer is partially attached, and at least the indicator ink layer is covered and peelable between the base sheet and the ink-penetrating sheet. A temperature history indicator sheet having an intervening release sheet is disclosed. It is disclosed that the temperature history of the test object can be monitored by peeling off the release sheet.

Japanese Patent Laid-Open No. 10-287863 JP-A-10-267761

  Since the temperature history display body disclosed in Patent Document 1 is switched on when placed in an environment of a specific temperature or lower, there is a risk of being switched on when the user does not intend. .

  The temperature history display body disclosed in Patent Document 2 can be operated at any timing by peeling off the release sheet. However, it is necessary to lift the ink-penetrating sheet once, peel off the release sheet, and then bond the ink-penetrating sheet onto the substrate. Although it is assumed that the temperature history display body is used in an existing production line for pharmaceuticals or foods, it is difficult to make it operable without reducing the line speed of the production line. Further, when the ink in the lower ink layer is diffused into the upper ink permeation layer, ink bleeding occurs, and it is difficult to maintain high-definition print information.

  Therefore, an object of the present invention is to provide a temperature history display body that can be stored at room temperature and can be easily operated at an arbitrary timing.

  In order to solve the above problems, the temperature history display body according to the present invention melts when a predetermined temperature is exceeded, a base material, a color developing layer containing a color developing agent, a color developer for promoting color development or discoloration of the color developing agent. A temperature-sensitive layer containing a temperature-sensitive agent; and a diffusion-preventing layer disposed between the color-forming layer and the temperature-sensitive layer and preventing diffusion of the developer into the color-forming layer. The prevention layer and the color-developing layer are laminated in this order, and the side surface of the temperature-sensitive layer laminate is covered with a non-porous member, and the diffusion prevention layer is non-porous by an adhesive that peels below the freezing point of the temperature-sensitive agent. It is fixed to the member.

  According to the present invention, it is possible to provide a temperature history display body that can be stored at room temperature and can be easily operated at an arbitrary timing.

It is a top view of the temperature history display body at the time of room temperature storage concerning one embodiment. It is AA 'sectional drawing of the temperature history display body which concerns on FIG. It is BB 'sectional drawing of the temperature history display body which concerns on FIG. It is AA 'sectional drawing of the temperature history display body at the time of the room temperature storage which concerns on one Embodiment. It is sectional drawing of the temperature history display body before detecting the deviation of the management temperature which concerns on one Embodiment. It is a top view of the temperature history display body before detecting the deviation of the management temperature which concerns on one Embodiment. It is sectional drawing of the temperature history display body after detecting the deviation of the management temperature which concerns on one Embodiment. It is a top view of the temperature history display body after detecting the deviation of the management temperature which concerns on one Embodiment. It is a figure which shows an example of the usage method of a temperature history display body. It is sectional drawing of the temperature history display body at the time of room temperature management which concerns on one Embodiment. It is a top view of the temperature history display body at the time of room temperature management concerning one embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a top view of a temperature history display body during room temperature storage according to an embodiment of the present invention. 2 is a cross-sectional view taken along the line AA ′ of the temperature history display body according to FIG. 1, and FIG. 3 is a cross-sectional view taken along the line BB ′. The temperature history display body includes a base material 2, a temperature-sensitive layer 12, a diffusion prevention layer 6, and a coloring layer 7. On the base material 2, the temperature sensitive layer 12, the diffusion preventing layer 6, and the color developing layer 7 are laminated in this order. An adhesive layer 1 is provided under the substrate 2.

  The temperature-sensitive layer 12 includes a developer that promotes color development or discoloration of the color former and a temperature-sensitive agent that melts at a predetermined temperature or higher. 2 and 3, the temperature-sensitive layer is composed of a first layer 3 containing a developer and a second layer 4 laminated on the first layer 3 and containing the temperature-sensitive agent. The second layer 4 plays a role of separating the color developing layer from the developer. The side surface of the temperature sensitive layer is covered with a non-porous member 11. In FIG. 2, the non-porous member covering the side surface of the temperature sensitive layer is integrated with the base material. The non-porous member and the base material that cover the side surface of the temperature sensitive layer may not be integrated.

  The diffusion preventing layer 6 plays a role of preventing the temperature-sensitive agent melted during storage at room temperature from diffusing into the coloring layer. The diffusion preventing layer 6 is fixed to the non-porous member by the adhesive 5. The pressure-sensitive adhesive 5 has a property of peeling below the freezing point of the temperature-sensitive agent. By adhering the diffusion preventing layer to the non-porous member with the adhesive, the temperature sensitive agent can be surely confined in the space surrounded by the diffusion preventing layer 6 and the substrate 2.

  As shown in FIG. 3, the coloring layer is bonded to at least a part of the non-porous member that covers the side surface of the temperature-sensitive agent. Since the coloring layer is fixed to the non-porous member, it is possible to suppress the deviation of the coloring layer when the diffusion preventing layer is pulled out. When the shape of the temperature history display body as viewed from above is a square shape, the diffusion preventing layer may be fixed to the non-porous member with an adhesive on one side (FIG. 4) or fixed on two sides. (FIG. 1). When the diffusion preventing layer and the non-porous member are bonded on one side as shown in FIG. 4, it is preferable that the coloring layer and the non-porous member are bonded on the other three sides. Further, when the diffusion preventing layer and the non-porous member are bonded at two sides as shown in FIG. 1, the coloring layer and the non-porous member are bonded at the other two sides as shown in FIG. Is preferred.

  The temperature history display body according to FIG. 1 cools below the freezing point of the temperature sensitive agent during use. After the second layer is solidified and pasted to the object to be measured via the adhesive layer 1, the diffusion preventing layer 6 is pulled out so that the temperature can be detected. The temperature history display according to the present embodiment has a layer structure having a temperature-sensitive layer and a coloring layer, and there is a possibility that the coloring condition may change due to the contact interface of each layer being disturbed when the diffusion prevention layer is pulled out. Since the pressure-sensitive adhesive 5 peels below the freezing point of the temperature-sensitive agent, the diffusion preventing layer can be easily pulled out without exerting stress on each layer.

  FIG. 5 shows a state before temperature deviation of the temperature history display body according to FIG. 2, and FIG. 6 shows a top view thereof. As the temperature-sensitive agent, a substance that melts at the upper limit of the temperature to be controlled is used. When stored at an appropriate temperature, the temperature-sensitive agent remains solid, so that the second layer suppresses the contact between the developer and the coloring layer, and the developer does not diffuse into the coloring layer. . Therefore, the color former does not develop or change color.

  FIG. 7 is a sectional view showing a state after temperature deviation of the temperature history display body according to FIG. 2, and FIG. 8 is a top view thereof. When stored at a temperature higher than the proper management temperature, the temperature sensitive agent melts. As a result, the developer diffuses through the second layer to the coloring layer, and the coloring agent and the developer react to develop or change color. As a result, the color former 8 becomes a color former 9 that has developed or changed color. As described above, temperature deviation can be detected and displayed.

  The temperature history display attached to the object to be measured managed at an appropriate temperature can be used again by returning the diffusion preventing layer between the color developing layer and the temperature sensitive layer.

  Hereinafter, members constituting the temperature history display body according to the embodiment will be described.

<Coloring layer>
The coloring layer includes a coloring agent and a carrier that holds the coloring agent on the surface.

  As the color former, it is possible to use a substance that is visually colorless or light-colored, but whose structure is changed by touching an acidic substance or a basic substance, and which is colored or discolored visually. Here, a substance that is colorless or light-colored at a neutral pH of about 5 or more and less than 8 and that develops or changes color when the pH is less than about 5 is referred to as “a substance that develops color by touching an acidic material”. A substance that develops or changes color at a pH of about 8 or more is referred to as a "substance that develops color by touching a basic material". In addition, there are compounds that exhibit different colors in acidic, neutral, and basic depending on the substance, so substances that fall under both “substances that develop color by touching acidic materials” and “substances that develop color by touching basic materials” There is also. Examples of the “substance that develops color by touching an acidic material” include methyl violet carbinol base, malachite green carbinol base, thymol blue, methyl yellow, and methyl orange. Examples of “substances that develop color by touching basic materials” include thymol blue, phenol red, phenolphthalein, naphtholphthalein, cresol red, alizanin yellow, thymolphthalein, bromophenol blue, bromothymol blue, etc. It is done.

  The color former is weak in color and may have low visibility when it is brought into contact with an acidic or basic developer layer. In that case, moisture may coexist. Some color formers improve color development by containing moisture. For example, phenolphthalein produces a very light pink color when water is not present together, but when it is slightly coexisted with water, it is well colored in pink.

  As the carrier for holding the color former, a porous member having pores that can hold the color former can be used. It is preferably continuous porous so that the developer can penetrate. The material is required to be a material that does not denature even when the developer and color former are in contact with each other for a long time. For example, polyethylene, polypropylene, cellulose, and other polymers that are difficult to dissolve in ordinary organic solvents, and inorganic compounds such as silicon dioxide are suitable.

  Further, from the viewpoint of diffusion of the developer into the color developing layer, a material excellent in diffusibility in the thickness direction is preferable. Further, from the viewpoint of suppressing printing bleeding, a material in which the color former and the developer are difficult to diffuse in the in-plane direction is preferable. Specifically, inkjet print paper and mat paper are preferable. Ink jet print paper is filled with an inorganic substance such as talc or silica in the thickness direction of the paper surface. For this reason, since the liquid is more easily diffused in the thickness direction than in the in-plane direction, it is possible to suppress the bleeding of the print. Further, by adjusting the thickness of the printing paper, the time for contact between the developer and the color former can be adjusted, and the time from the deviation from the set temperature to the color development can be controlled.

The coloring layer preferably contains a polymer having an amino group. Carbon dioxide substances in the air that develops color by touching the acidic substance, or SO _X, for color development in contact with the gas of acid such as NO _X, there is a risk of coloration also be stored in a temperature region not originally colored . Since the amino group exhibits basicity, the color former layer material can always be kept basic even after the formation of the marking by coexisting a compound having an amino group. As a result, it is possible to suppress color development due to exposure to acidic gas. The compound having an amino group is preferably a polymer having low crystallinity or an amorphous polymer. A low-crystalline or amorphous polymer can form a color former layer in a substantially uniformly dispersed state after being mixed with the color former layer material. As the polymer having an amino group, for example, polyethyleneimine, polyallylamine and the like are suitable.

  The color former preferably further contains a conductive agent. By including a conductive agent, printing can be performed with a charge control type ink jet printer. By printing the color former with an inkjet printer, it can be printed as characters, symbols, one-dimensional codes, two-dimensional codes, and the like. As a result, information other than the temperature information of the temperature history display body can be given. Furthermore, by using a two-dimensional code or the like, it is possible to convert the presence or absence of temperature deviation into data using a reading device.

  As the conductive agent, a compound having a metal salt structure is preferable. Considering solubility in a solvent and corrosion of members, nitrate ions, perchlorate ions, and tetraphenylborate ions are preferable as the anions forming the metal salt structure compound. As the cation forming the compound having a metal salt structure, lithium ion, sodium ion, ammonium ion, and tetramethylammonium ion are preferable. In addition to the surfactant for improving the dispersibility of the color former, the color former may contain a leveling agent for controlling the shape after the ink has landed on the substrate to be printed.

  The coloring layer may include a cord that does not change with temperature. The code preferably has information such as a management temperature (melting point of the temperature-sensitive agent), the position, number, and type of the color former. For example, by providing a code having position information (relative position with respect to the code) of the color former, it is easy to read color data or the like with a reading device.

<Temperature sensitive layer>
The temperature-sensitive layer includes a temperature-sensitive agent, a developer, and a carrier that holds these. The temperature sensitive agent includes a first layer composed of a developer and a carrier impregnated with the developer, and a second layer composed of the temperature sensitive agent and the carrier impregnated with the temperature sensitive agent. It is preferable to include. Hereinafter, the first layer and the second layer will be described.

(1) 2nd layer As a thermosensitive agent, the substance which melt | dissolves when it exceeds predetermined temperature can be used. For example, for example, a long-chain hydrocarbon not containing an acidic group or a basic group, or a hydrocarbon having several branches is preferable. In addition, an alcohol having a long-chain hydrocarbon chain or a branched hydrocarbon chain, a diol, a ketone, an amide having a long-chain hydrocarbon chain or a branched hydrocarbon chain, an ether, an ester, or the like can be used. Examples of the hydrocarbon of a long chain, branched hydrocarbon chain, or cyclic hydrocarbon chain include cyclodecane (9 ° C.), dodecane, tetradecane (6 ° C.), hexadecane (17 ° C.), octadecane (28 ° C.), and the like. The parentheses are melting points. Examples of the hydroxyl-terminated alcohol or diol include 1,4-butanediol (20 ° C.), 1-decanol (6 ° C.), 1-dodecanol (24 ° C.), 1,2-dodecane diol (58 ° C.), 2 -Tetradecanol (34 degreeC) etc. are mentioned. Examples of the material having a ketone structure include 2-decanone (3 ° C.), propiophenone (18 ° C.), butyrophenone (12 ° C.), isobutyrophenone (1 ° C.), hexanophenone (26 ° C.), octanophenone (22 ° C), decanophenone (35 ° C) and the like.

  Among these, isopropyl palmitate, isopropyl myristate, and pentadecane are preferable as the temperature sensitive agent.

  The selection of the temperature sensitive agent differs depending on the upper limit of the management set temperature of the product to be temperature controlled. For example, in the case of frozen foods such as meat, since the upper limit of the control set temperature is around −16 ° C., a compound such as 1-octanol or 2-octanone having a melting point of −16 ° C. may be used as the temperature sensitive agent. In the case of frozen foods such as seafood, 3-octanone having a melting point of −23 ° C. is a candidate. In the case of carbohydrate-based products, dodecane having a melting point of −12 ° C. is a candidate for storage at a slightly higher temperature. If the product you want to control the temperature of is a pharmaceutical product that requires storage below 10 ° C, tetradecane with a melting point of 6 ° C, 1-decanol, 2-dodecane with a melting point of 3.5 ° C, hexadecane with a melting point of 17 ° C, or It is preferable to adjust the melting point to about 10 ° C. by adding 3-dodecanone having a melting point of 19 ° C. and 2-dodecanone having a melting point of 20 ° C.

  These temperature-sensitive agents can be used alone, but a mixture of compounds having a higher melting point may be used. This is because by mixing a compound having a high melting point, the crystallinity is lowered and becomes amorphous, the temperature sensitive agent becomes dense, and the shielding property between the color former and the developer is improved. In particular, the amorphousness is increased by mixing compounds having similar structures. For example, by adding tetradecane having a melting point of 6 ° C. or hexadecane having a melting point of 17 ° C. to dodecane having a melting point of −12 ° C., the temperature-sensitive layer becomes amorphous, and between the color former layer and the developer layer. This improves the shielding performance. The temperature at which the temperature-sensitive layer containing a plurality of temperature-sensitive agents softens depends on the melting point and addition rate of the mixed materials. For example, when a material a having a high compatibility and a material a having a melting point of A ° C and a material b having a melting point of B ° C are mixed in an equal amount, the melting point is approximately between A and B. However, when the difference between the melting points of the two materials is large, specifically, when the temperature is 50 ° C. or higher, the temperature at which the temperature-sensitive layer softens or melts becomes substantially the same as the melting point of the lower melting material. Even when materials with low compatibility are used, the temperature at which the temperature-sensitive layer softens or melts is substantially the same as the melting point of the lower melting material.

  Further, the temperature sensitive agent and the developer need to have low compatibility. For example, when the temperature sensitive agent is a hydrophobic material, a hydrophilic material is used as the developer. When the compatibility is low, the temperature-sensitive agent and the developer are not mixed, so that the developer cannot diffuse into the color-forming layer after the temperature-sensitive agent has diffused into the color-forming layer. By using a temperature-sensitive agent and a developer that are not compatible with each other, even if the temperature-sensitive agent melts during storage at room temperature before removing the diffusion prevention layer, the temperature-sensitive agent and the developer are not mixed. It is possible to suppress the demonstrator from diffusing into the second layer. The carrier impregnated with the temperature sensitive agent may be a porous member that does not hinder the diffusion of the developer into the coloring layer. For example, in addition to natural fibers and organic chemical fibers, non-woven fabric composed of carbon fibers, glass fibers, metal fibers, or paper composed of cellulose fibers is desirable. It is also possible to use a silicon dioxide, polyethylene, or polypropylene powder by holding it with a binder having the same chemical structure to form a continuous porous body. The temperature-sensitive agent used in the present invention is configured to melt and diffuse into the coloring layer when it deviates from the control temperature, and the colored ink may be swept away by the diffused temperature-sensitive agent. For this reason, it is desirable that the amount of the temperature sensitive agent held on the carrier used for the second layer is small. On the other hand, when the temperature history display body is below the control temperature, the second layer solidified below the freezing point has no pinholes, and it is important to reliably prevent the developer from diffusing. For this reason, it is desirable that the diameter of the pores constituted by the fibers of the temperature-sensitive agent-impregnated carrier is small.

  Further, the pore median diameter of the carrier impregnated with the temperature-sensitive agent is preferably 11 μm or more and 18 μm or less when measured by a mercury intrusion method. By making the thickness 18 μm or less, pinhole formation can be suppressed. By setting the thickness to 11 μm or more, a desired diffusion rate can be obtained.

  In addition, it is possible to adjust the time from temperature deviation to color development by adjusting the thickness of the second layer.

(2) First layer The developer is an acidic substance or a basic substance, and is selected according to the color former. Examples of the acidic substance include a polymer having a carboxyl group or a sulfonic acid group. Specifically, polyacrylic acid, polymethacrylic acid, polystyrene sulfonic acid, copolymer of styrene and polyacrylic acid, copolymer of methyl acrylate and acrylic acid, copolymer of ethyl acrylate and acrylic acid, acrylic Copolymer of propyl acid and acrylic acid, copolymer of butyl acrylate and acrylic acid, copolymer of hexyl acrylate and acrylic acid, copolymer of octyl acrylate and acrylic acid, methyl methacrylate and acrylic acid Copolymer, Copolymer of ethyl methacrylate and acrylic acid, Copolymer of propyl methacrylate and acrylic acid, Copolymer of butyl methacrylate and acrylic acid, Copolymer of hexyl methacrylate and acrylic acid, Methacrylic acid Copolymer of octyl and acrylic acid, copolymer of styrene and polymethacrylic acid, methyl acrylate and Copolymer of tacrylic acid, copolymer of ethyl acrylate and methacrylic acid, copolymer of propyl acrylate and methacrylic acid, copolymer of butyl acrylate and methacrylic acid, copolymer of hexyl acrylate and methacrylic acid , Octyl acrylate and methacrylic acid copolymer, methyl methacrylate and methacrylic acid copolymer, ethyl methacrylate and methacrylic acid copolymer, propyl methacrylate and methacrylic acid copolymer, butyl methacrylate and methacrylic acid Acid copolymer, hexyl methacrylate and methacrylic acid copolymer, octyl methacrylate and methacrylic acid copolymer, styrene and styrene sulfonic acid copolymer, methyl acrylate and styrene sulfonic acid copolymer, Copolymer of ethyl acrylate and styrene sulfonic acid, propyl acrylate and Tylene sulfonic acid copolymer, butyl acrylate and styrene sulfonic acid copolymer, hexyl acrylate and styrene sulfonic acid copolymer, octyl acrylate and styrene sulfonic acid copolymer, methyl methacrylate and styrene sulfone Copolymer of acid, copolymer of ethyl methacrylate and styrene sulfonic acid, copolymer of propyl methacrylate and styrene sulfonic acid, copolymer of butyl methacrylate and styrene sulfonic acid, hexyl methacrylate and styrene sulfonic acid Examples include copolymers, copolymers of octyl methacrylate and styrene sulfonic acid, polyaspartic acid, polyglutamic acid, and polyvinylphenol.

  Examples of the basic substance include polymers having an amino group such as polyethyleneimine, polyallylamine, chitosan, polylysine, polyarginine, and polyaniline. What dissolved these in the alcohol-type solvent can be used as a color developer. In the case of an aliphatic diamine that is solid at room temperature, specific examples include diaminohexane, diaminooctane, diaminodecane, diaminododecane, etc., and those obtained by dissolving these in an alcohol solvent may be used as the developer. it can. In the case of aliphatic monoamines, specific examples include octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, etc., and those dissolved in alcoholic solvents should be used as the developer. Can do.

  Among these developers, polymethacrylic acid, polystyrene sulfonic acid, a copolymer of styrene and polyacrylic acid, a copolymer of methyl acrylate and acrylic acid, a copolymer of ethyl acrylate and acrylic acid, Chitosan, polylysine, polyarginine and polyaniline are preferred, and polyacrylic acid, polyallylamine and polyethyleneimine are more preferred.

  In the present invention, the developer and the color former react by liquid diffusion of the developer into the color development layer. Therefore, it is preferable to use the developer by dissolving it in a solvent such as water or ethanol. The solvent to be used can be selected depending on the set management temperature. For example, it is preferable to use water as a solvent for temperature traceability in refrigerated storage.

  The carrier impregnated with the developer may be a material that is a porous member and can hold a sufficient developer for color development. For example, in addition to natural fibers and organic chemical fibers, non-woven fabric composed of carbon fibers, glass fibers, metal fibers, or paper composed of cellulose fibers is desirable. In addition, when using for the temperature traceability marking of a pharmaceutical or a foodstuff, the safety | security of material becomes important. That is, it is an important selection criterion that it is harmless to the human body.

<Members that cover the side surfaces of the substrate and the temperature-sensitive layer>
Any member that covers the side surfaces of the substrate and the temperature-sensitive layer may be a non-porous member. For example, an inexpensive film having high resistance to various organic solvents such as polyethylene is desirable. Polyethylene terephthalate (hereinafter abbreviated as PET) is suitable because it has excellent low-temperature durability and easily imparts adhesion and transparency. Furthermore, polypropylene, polystyrene, acrylic resin, polycarbonate, cyclic olefin resin, and the like can be used.

  Moreover, it is preferable that a base material equips the back surface with the adhesion layer. The adhesive layer makes it easy to attach the temperature history display body to the management object.

<Adhesive>
The pressure-sensitive adhesive is not particularly limited as long as it has a property of peeling below the freezing point of the temperature-sensitive agent.
Here, the adhesive force (N / mm) at the freezing point of the temperature-sensitive agent is preferably smaller than the adhesive force at a temperature 20 ° C. higher than the freezing point of the temperature-sensitive agent. Specifically, the adhesive force (N / mm) at the freezing point of the temperature-sensitive agent is preferably 1/10 or less of the adhesive force at a temperature 20 ° C. higher than the freezing point of the temperature-sensitive agent. By using such a pressure-sensitive adhesive, the diffusion prevention layer can be smoothly extracted while the temperature-sensitive layer is solidified. In addition, the adhesive strength with the diffusion preventing layer below the freezing point of the temperature-sensitive agent is weaker than the adhesive strength with the non-porous member (base material), and the adhesive preferably remains on the non-porous member.

  As the pressure-sensitive adhesive, for example, a temperature-sensitive pressure-sensitive adhesive tape including a pressure-sensitive adhesive layer containing methyl acrylate and acrylic acid ester can be used. This temperature-sensitive adhesive tape has a characteristic that it is 90% or less of the peel strength at the time of adhesion by bonding the substrate and the adhesive tape and then cooling it at 15 to 20 ° C. from this adhesion temperature. When the above effects are compared between a PET base material and a polyimide base material, the effect is remarkable in the polyimide base material. For this reason, it is more preferable that the diffusion preventing layer is a polyimide tape and the base material is a PET tape. In this case, when the diffusion preventing layer is pulled out by cooling at 15 to 20 ° C. from the bonding temperature, the polyimide tape is peeled off from the temperature-sensitive adhesive tape, and the temperature-sensitive adhesive tape remains on the PET tape.

<Diffusion prevention layer>
The diffusion preventing layer only needs to block the color developing layer and the temperature sensitive layer. For example, a glass plate, a resin film such as polyethylene terephthalate (PET) or polytetrafluoroethylene (PTFE), a resin sheet, a resin tape, a rubber sheet, or the like can be used. Among these, a polyimide base material is particularly preferable.

  Moreover, it is preferable to provide a member having a higher friction coefficient than the diffusion preventing layer at the end of the diffusion preventing layer. It is necessary for the temperature history display body to remove the diffusion prevention layer at the start of temperature detection. In order to remove the diffusion prevention layer at a high speed on the production line, a label peeling device or the like is used to pull out the diffusion prevention layer while holding a part of the diffusion prevention layer. For this reason, it is preferable that the edge part of a diffusion prevention layer has a high friction coefficient.

  Moreover, it is desirable that the thickness of the diffusion preventing layer is thin for the following reasons. That is, it is necessary to remove the diffusion preventing layer at the start of temperature detection, and to diffuse the temperature-sensitive agent and developer to the printing paper when the temperature deviates. For this reason, it is desirable that the gap between the coloring layer and the temperature-sensitive layer after removing the diffusion preventing layer is small, and a thin diffusion preventing layer is desirable. However, as described above, strength is also necessary for extracting the diffusion layer in the production line, and the thickness of the diffusion prevention layer is preferably 5 μm or more and 10 μm or less in order to achieve both thinness and strength.

<Manufacturing method of temperature history body>
The method for producing a temperature history display body according to the embodiment includes a temperature-sensitive layer forming step of forming a temperature-sensitive layer by cooling the temperature-sensitive agent to a freezing point or lower, a color-forming layer forming step of printing a color former on printing paper, A lamination step of laminating the base material, the temperature-sensitive layer, and the diffusion prevention layer; and a printing paper lamination step of laminating the printing paper on the diffusion prevention layer at room temperature after the lamination step.

  According to the said method, a temperature history display body can be manufactured at room temperature except a temperature sensitive layer formation process and a lamination process. The color forming layer forming step may be performed after the printing paper laminating step.

<How to use temperature history display>
The temperature history display body can be used as follows, for example. A temperature history display body is attached to the temperature management object or its container, and the temperature history display body is brought into a temperature detectable state by pulling out the diffusion prevention layer. Then, it is determined whether or not the color layer is controlled at an appropriate temperature from the presence or absence of color change or color development.

  FIG. 9 is a diagram illustrating an example of a method of using the temperature history display body. First, a temperature history display body in which a color former is not printed on the color development layer is prepared. A temperature history display 14 is attached to a container 13 of a temperature management object such as an ampule with a labeler. A coloring agent is printed on the coloring layer by a printing device 15 such as an ink jet printer. At this time, the pasting of the temperature history display body 14 and the printing on the coloring layer can be performed at room temperature. Next, the temperature control object is put into a container under temperature control. Thereafter, the diffusion preventing layer 6 is removed by the film removing device 17 or the like. By doing in this way, a temperature history display body can be stuck on a temperature management object in a manufacturing line, and it can be set as the state which can detect a temperature deviation.

<Method for manufacturing temperature history display>
The ink was prepared by the following procedure. Bromophenol blue (Wako Pure Chemicals, 4g) is dissolved in ethanol (Wako Pure Chemicals, 240g), and lithium nitrate (Wako Pure Chemicals, 1.4g) is added as a conductive material, and contains a color former. Ink was used. Using this ink, printing is performed on the center of inkjet printer paper (thickness 0.3mm, width 10mm, length 20mm), 5x10mm with Hitachi Industrial Equipment, continuous ink jet printer, PX-R type, and the coloring layer Formed.

Next, a 30% polyethyleneimine aqueous solution (average molecular weight: about 70,000, manufactured by Wako Pure Chemical Industries, 2 g) was diluted with 20 g of distilled water to prepare a developer solution. A high-quality paper of 40 g / m ² was cut into a width of 5 mm and a length of 10 mm, and impregnated with a developer solution to form a first layer. This was arrange | positioned on the base material tape made from PET. Next, a 20 g / m ² thin paper sheet cut to a width of 6 mm and a length of 11 mm was impregnated with isopropyl myristate (manufactured by Wako Pure Chemical Industries, Ltd., melting point: 9 ° C.) to form a second layer. Laminated on the other layer. Next, an interim tape (manufactured by Nitta Co., Ltd.), which is a thermosensitive adhesive tape, was applied to a 5 μm thick polyimide tape (manufactured by Toray DuPont) to prepare a diffusion preventing layer. While this was arrange | positioned on a temperature sensitive layer, the base material tape and the temperature sensitive adhesive tape were adhere | attached at 25 degreeC or more. On top of this, a printing paper on which coloring ink is printed as a coloring layer is laminated, and the printing paper and the base tape are fixed with an adhesive tape so as not to disturb the movement of the diffusion preventing layer, and the temperature history shown in FIG. The display was completed.

  Next, this tape was stored in a thermostat set at 0 ° C. for 1 hour to solidify the temperature sensitive agent in the temperature sensitive layer.

<Thermochromic confirmation experiment>
The above-mentioned temperature history display body was transferred to a thermostat set to 4 ° C., and the temperature history display body was attached to the curved surface of a pharmaceutical bottle that is a measurement object. Next, the diffusion prevention layer was pulled out, and the temperature detection of the temperature history display body was operated as shown in FIG. Although it stored at 4 degreeC for 24 hours by the thermostat, there was no change in the temperature history display body. Next, when the set temperature of the thermostat was set to 9 ° C., the temperature-sensitive agent began to melt, and after 30 minutes, as shown in FIG. 3, the developer diffused and contacted with the printing ink as the color former. Ink discoloration was confirmed.

  A temperature history display was prepared in the same manner as in Example 1 except that printing paper (inkjet printer paper) was laminated on the diffusion preventing layer, and then ink containing a color former was printed.

  First, a temperature history display body in which ink containing a color former was not printed on the color development layer was prepared. This temperature history display body was stored in a thermostat set at 0 ° C. for 1 hour to solidify the temperature sensitive agent. Next, this temperature history display body was moved to a thermostat set to 4 ° C., and the temperature history display body was affixed to the curved surface of a pharmaceutical bottle that is a measurement object. The printer head of the continuous ink jet printer described in Example 1 was placed in a thermostatic chamber, and ink containing a color former was printed on the printing paper constituting the color development layer.

  A thermochromic experiment was performed in the same manner as in Example 1 to confirm ink discoloration. In this method, the lot number and date of manufacture could be directly printed on the pharmaceutical bottle with colored ink.

(Comparative Example 1)
The temperature history display is the same as in Example 1 except that the diffusion preventive layer is affixed to the base material using a natural rubber-based adhesive tape (containing Pico Pale 100 (manufactured by Rika Kakyures)) as the adhesive. A body was prepared and a thermochromic confirmation experiment was conducted.

  Since the temperature history display body according to Comparative Example 1 uses the same temperature-sensitive agent as in Example 1, the color forming layer should be discolored at 9 ° C. or higher. However, the color change of the ink was confirmed at 4 ° C. This is considered to be because the temperature-sensitive layer is damaged when the diffusion preventing layer is pulled out.

  Bromothymol blue (Wako Pure Chemical, 6 g) is dissolved in ethanol (Wako Pure Chemical, 230 g) as an ink containing a color former, and lithium nitrate (Wako Pure Chemical, 1.5 g) is used as a conductive material. A temperature history display was prepared in the same manner as in Example 1 except that the ink obtained by addition was used, and a thermochromic confirmation experiment was performed.

  Although stored in a thermostatic bath at 4 ° C. for 24 hours, there was no change in the temperature history display. Thereafter, when stored at 9 ° C., the ink started to change from yellow to blue after 6 minutes. Furthermore, the color change of printing was completed after 14 minutes. Again, the set temperature was 4 ° C., but the print remained blue. After this, the temperature history display was taken out from the thermostat and analyzed, and as a result, the temperature sensitive layer melted and diffused to the printing paper, and the developer was in contact with the printing ink as the color former and developed color. It was confirmed.

  A temperature history display was produced in the same manner as in Example 1 except that isopropyl palmitate (manufactured by Wako Pure Chemical Industries, Ltd., melting point: 12 ° C.) was used as the temperature sensitive agent. Further, a thermochromic confirmation experiment was conducted in the same manner as in Example 1 except that the set temperature was changed from 5 ° C. to 12 ° C. and the temperature at which the diffusion preventing layer was pulled out was 5 ° C.

  First, it was stored in a thermostatic bath at 5 ° C. for 24 hours, but there was no change in the temperature history display. Thereafter, the temperature history display body did not change up to the set temperature of 11 ° C., but when stored at 12 ° C., the ink started to change from colorless to blue after 9 minutes. Further, the color change of printing was completed after 18 minutes. Again, the set temperature was 4 ° C., but the print remained blue. Thereafter, the tape was taken out from the thermostat and analyzed, and as a result, it was confirmed that the temperature sensitive layer melted and diffused to the printing paper, and that the developer was in contact with the printing ink and colored.

  As described above, the first layer containing the color developer, the second layer containing the temperature sensitive agent, the diffusion preventing layer with the temperature sensitive adhesive tape attached, and the color developing layer on which the color ink is printed are formed on the tape base material. In the laminated temperature history display body, after the temperature sensitive agent is solidified below the freezing point of the temperature sensitive agent after storage at room temperature, temperature detection starts by removing the diffusion prevention layer, and from the control temperature of the object to be measured. It was confirmed that the deviation of Moreover, it turned out that preset temperature can be adjusted by selecting the kind of thermosensitive agent to be used.

  A tape (non-slip tape manufactured by 3M Co., Ltd.) in which a silicone adhesive was applied to glass fiber reinforced silicone was applied to the end portion 5 mm of the diffusion preventing layer, and a temperature history display was produced in the same manner as in Example 1. A sectional view of the produced temperature history display body is shown in FIG. 10, and a top view is shown in FIG. 10 and 11, a non-slip tape 10 is provided at the end of the diffusion preventing layer 6. By providing a member having a higher coefficient of friction than the diffusion preventing layer, the diffusion layer can be reliably extracted.

DESCRIPTION OF SYMBOLS 1 ... Adhesion layer, 2 ... Base material, 3 ... 1st layer, 4 ... 2nd layer, 5 ... Adhesive, 6 ... Diffusion prevention layer, 7 ... Color development layer, 8 ... Color development agent, 9 ... Color development or discoloration Color developing agent, 10 ... Anti-slip tape, 11 ... Non-porous member, 12 ... Temperature sensitive layer, 13 ... Container, 14 ... Temperature history display, 15 ... Printing device, 16 ... Injection device, 17 ... Film removal device

Claims (17)

A substrate;
A coloring layer containing a coloring agent;
A temperature-sensitive layer comprising: a developer that promotes color development or discoloration of the color former; and a temperature-sensitive agent that melts when a predetermined temperature is exceeded;
A diffusion preventing layer disposed between the color forming layer and the temperature sensitive layer and preventing diffusion of the developer into the color developing layer;
On the base material, the temperature sensitive layer, the diffusion preventing layer, and the coloring layer are laminated in this order.
The side surface of the temperature sensitive layer is covered with a non-porous member,
The temperature history display body, wherein the diffusion preventing layer is fixed to the non-porous member by an adhesive that peels below the freezing point of the thermosensitive agent. The temperature history display body according to claim 1,
The temperature history display body characterized in that the adhesive strength of the adhesive at the freezing point is lower than the adhesive strength of the adhesive at a temperature 20 ° C. higher than the freezing point. The temperature history display body according to claim 1,
The temperature-sensitive display body, wherein the temperature-sensitive layer includes a first layer containing the developer and a second layer laminated on the first layer and containing the temperature-sensitive agent. The temperature history display body according to claim 1,
The diffusion history preventing layer is a glass history sheet, a resin film, a resin sheet, or a rubber sheet. The temperature history display body according to claim 3,
The temperature history display body, wherein the diffusion preventing layer has a thickness of 5 μm or more and 10 μm or less. The temperature history display body according to claim 1,
The temperature history display body, wherein the pressure-sensitive adhesive has a multi-layer structure, and has a lower adhesive strength against the diffusion preventing layer than an adhesive strength against the non-porous member. The temperature history display body according to claim 1,
The temperature history display body, wherein the base material and the non-porous member are integrated. The temperature history display body according to claim 1,
The temperature history display body, wherein the color former contains a conductive agent. The temperature history display body according to claim 1,
The temperature history display body characterized in that the melting point of the temperature-sensitive agent is 10 ° C. or less. The temperature history display body according to claim 1,
The temperature-history display body, wherein the color-developing layer is formed by printing the color-developing agent on a carrier holding the color-developing agent. The temperature history display body according to claim 1,
A temperature history display body comprising a member having a higher friction coefficient than the diffusion preventing layer at an end of the diffusion preventing layer. The temperature history display body according to claim 1,
The temperature history display body, wherein the developer contains any of polyacrylic acid, polyallylamine, and polyethyleneimine. The temperature history display body according to claim 1,
The temperature-sensitive display body, wherein the temperature-sensitive agent contains any of isopropyl palmitate, isopropyl myristate, and pentadecane. The temperature history display body according to claim 1,
The temperature-history display body, wherein the color former contains at least one of thymol blue, bromothymol blue, and bromothymol blue. A temperature history display body according to any one of claims 1 to 14,
A temperature history display body comprising a code on the surface of the color developing layer, which has information relating to the melting point of the thermosensitive agent or the position of the color former and does not change with temperature. A temperature-sensitive layer including a base material, a color-developing layer containing a color-developing agent, a developer that promotes color development or discoloration of the color-developing agent, and a temperature-sensitive agent that melts when a predetermined temperature is exceeded, the color-developing layer, and the temperature-sensitive layer A diffusion preventing layer disposed between layers and preventing diffusion of the developer into the color developing layer, and a method for producing a temperature history display body comprising:
A temperature-sensitive layer forming step of cooling the temperature-sensitive agent to a freezing point or lower to form the temperature-sensitive layer; and
A coloring layer forming step of printing the color former on printing paper;
A laminating step of laminating the base material, the temperature sensitive layer, and the diffusion preventing layer;
After the said lamination process, the manufacturing method of a temperature history display body provided with the printing paper lamination process which laminates | prints a printing paper on the said diffusion prevention layer at room temperature. A temperature-sensitive layer including a base material, a color-developing layer containing a color-developing agent, a developer that promotes color development or discoloration of the color-developing agent, and a temperature-sensitive agent that melts when a predetermined temperature is exceeded, the color-developing layer, and the temperature-sensitive layer A diffusion preventing layer disposed between the layers and preventing diffusion of the developer into the coloring layer, and a method of using a temperature history display body comprising:
Affixing the temperature history display body to the temperature management object,
By pulling out the diffusion preventing layer, the temperature history display body is brought into a temperature detectable state,
A method for using a temperature history display body, characterized in that it is determined whether or not the color layer is controlled at an appropriate temperature based on a change in color or color development.

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