JP4882894B2 - Anti-tamper label - Google Patents

Description

  The present invention relates to a tamper-proof label that can identify traces such as malicious opening and mischief of a package or the like that contains medicines, foodstuffs, and the like. More specifically, when cut and opened, the color tone of the printing ink layer in the label changes with a chemical reaction depending on the presence or absence of carbon dioxide gas, and it is easy and reliable whether or not the label is cut and opened. The present invention relates to a tamper-proof label that can be identified.

  Since the tamper-proof label can be identified whether or not it has been peeled off after being attached to the adherend, in recent years it has been used for packages that contain products such as pharmaceuticals and foodstuffs. Widely used as sealing label. If tamper-proof labels are affixed as sealing labels to containers or packages that make up products that contain medicines, foods, etc., those products are displayed on display shelves and sold. Sometimes the seal label is peeled off and opened, and even if foreign matter is mixed inside and resealed, there remains a trace indicating that the seal label has been peeled off. This will be possible once. In addition, some of such sealing labels are configured so that, after being peeled, they cannot be attached again in the same state as before peeling, but such a label is also opened or unopened. Can be clearly shown to consumers.

Conventionally, as an anti-tampering label used to prevent malicious opening, mischief, etc., an anti-tampering adhesive label as shown in FIG. 6, that is, a label substrate 51 and a part of the label substrate 51 are laminated. Can be peeled off at the interface with the adherend 58 following the label base 51 and the easy peelable layer 52 having easy peelability, the label base 51 and the ink layer 53 laminated on the easy peelable layer 52. An anti-tampering adhesive label having a re-peelable followable adhesive layer 57, and an adhesive strength X _AB between the label substrate 51 and the easy peelable layer 52, and an adhesive strength XBC between the easy peelable layer 52 and the ink layer 53 _. , and at least one strength of the peelable layer 52 inside the fracture strength X _B is smaller than the adhesive strength X _D between releasable following pressure-sensitive adhesive layer 57 and the adherend 58, and the label substrate 51 and ink Adhesive strength X between layers 53 _AC, and the strength of adhesion strength X _CD between ink layer 53 and releasable following pressure-sensitive adhesive layer 57, tamper-evident adhesive label which has a larger relationship adhesion strength X _D is proposed in Patent Document 1 .

In such an anti-tampering pressure-sensitive adhesive label, when an object attached to a predetermined portion is to be peeled off, the interface (SA _B , S _BC) between the easy peelable layer 52 and the label base 51 and / or the ink layer 53 is used _. ), Or peeling or destruction occurs in the easily peelable layer 52 to form a void. That is, peeling or destruction occurs at the interface with the label substrate 51 in the easy peeling layer 52 (1), and peeling or breaking occurs in the easy peeling layer 52 at the easy peeling layer 52 (2). Furthermore, in the portion of the easy peelable layer 52 (3), peeling or destruction occurs at the interface between the easy peelable layer 52 (3) and the ink layer 53.

  When the adhesive label 50 after peeling is viewed from the label substrate 51 side, the pattern (design) that was orderly (or difficult to visually recognize) before peeling changes after peeling, for example, formation of an easy peeling layer A pattern corresponding to the pattern is visually recognized as being raised, and it is possible to identify whether the pattern has been peeled off after being stuck to the adherend 58. This is because the peeled portion is not restored to the same state as before peeling, and usually a cavity is formed or a displacement occurs. Therefore, in the easy peeling layer 52 and its peripheral part, This is because there is a difference in density or deviation from the part.

  Further, the surface base material, the pressure-sensitive adhesive layer and the release sheet are laminated, and on the surface base material, at least one self-coloring pressure-sensitive recording layer containing a microcapsule containing a basic dye and a developer is formed. Patent Document 2 proposes an adhesive sheet having an adhesive layer on the recording layer side for the purpose of preventing tampering.

  This pressure-sensitive adhesive sheet is obtained by bonding at least one self-coloring pressure-sensitive recording layer containing a microcapsule encapsulating a basic dye provided on one side of a surface base material and a color developer and a pressure-sensitive adhesive layer. When peeled off from the sticking body, the recording layer develops color due to its peeling resistance, so that the label can be easily discriminated against forgery, illegal use, presence / absence of opening, and the like.

  Furthermore, as a tamper-proof label, Patent Document 3 proposes a label used when sticking and sealing over a lid and a side wall of a package. As shown in FIG. 7, the tamper-proof label 60 is formed on the back surface of the base material 61 with an adhesive layer B1 to be attached to the package, and is curled by the tension tension f. The curl film 62 is formed on the back side of the packing body and the side wall side of the packing body when the curling film 62 is adhered to the lid side and the side walls. The both side portions 621 positioned respectively are configured as adhesive portions, and the center portion 622 sandwiched between them is configured as a non-adhesive portion.

Accordingly, after the tamper-proof label 60 is attached to the package K as shown in FIG. 8A, the lid K ₁ and the side wall K ₂ are sharpened with a sharp blade as shown in FIG. 8B. When cut along the boundary line L, the cut end 6220 of the curl film 62 immediately curls at the central portion 622 of the non-bonded portion, and the fact that the label is cut can be seen at a glance.

  The anti-tampering pressure-sensitive adhesive label proposed in Patent Document 1 is based on a physical means that makes re-sticking impossible using the difference in adhesion strength (peel strength) between layers of the layers constituting the label, The anti-tampering pressure-sensitive adhesive sheet proposed in Patent Document 2 is based on physical means that develops color due to peeling resistance when the label is peeled off from the adherend. However, a method using the above-described complicated adhesive strength (peel strength) difference or physical means of peel resistance is based on the usage environment (for example, temperature or humidity during use or storage) and the adhesive conditions [for example, , Pressing pressure (adhesion pressure), time for applying the adhesion pressure (adhesion time), adhesion period, etc.], and there is a concern that tampering cannot be reliably prevented.

  In addition, the tamper-proof label in which the adhesion part and the adherend part are provided between the curl film and the base material proposed in Patent Document 3 can reattach the cut curl film with an adhesive or the like. The label cutting may not be easily determined.

Patent documents are described below.
JP 2003-84672 A JP 2003-261840 A JP 2005-241749 A

  The present invention has been made to solve the above-described problems, and uses a chemical reaction that is not easily affected by the use environment, regardless of physical tampering prevention means. It is an object of the present invention to provide a tamper-proof label that can easily and reliably identify the presence or absence of a peeling action.

  In order to achieve the above object, the invention according to claim 1 includes at least a transparent carbon dioxide gas barrier film layer, a printing ink layer whose color tone changes depending on the presence or absence of carbon dioxide gas, and a carbon dioxide gas barrier layer. The tamper-proof label is characterized in that the laminate in which the adhesive layers are laminated in this relative order is sealed at the peripheral edge thereof, and the printing ink layer is enclosed.

  The invention according to claim 2 is the tamper-proof label according to claim 1, wherein the carbon dioxide gas barrier film layer having transparency and the carbon dioxide gas barrier layer are bonded to the peripheral edge of the previous layered product. A layer is provided, and the peripheral edge portion of the laminate is sealed by the adhesive layer.

  Furthermore, the invention according to claim 3 is the tamper-proof label according to claim 1, wherein the laminated body can be heat-sealed so as to be sandwiched between the transparent carbon dioxide gas barrier film layer and the carbon dioxide gas barrier layer. A pair of such resin layers are laminated, and the peripheral edge of the laminate is sealed with the pair of heat-sealable resin layers.

  According to the present invention, when it is cut and opened in order to peel off the pasted one, the color tone of the printing ink layer constituting a part thereof changes with the disappearance of carbon dioxide gas. Can be easily and reliably identified. Also, if it is used as a container or packaging body container or packaging body cap and container body, or a lid and side wall and used as a label for sealing the container or packaging body, malicious opening of the container or packaging body is prevented. It becomes easy to find and it is possible to prevent mischief, tampering, unloading and the like.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory view showing a part (part of the peripheral edge) of the structure of the tamper-proof label of the present invention. FIG. 2 is an explanatory view showing a part (part of the peripheral edge) of the structure of another tamper-proof label of the present invention. FIG. 3 is an explanatory perspective view showing a state in which the tamper-proof label of the present invention is pasted over the lid and side walls of the package and a state in which the pasted label is cut with a blade.

  An anti-tampering label 10 ′ shown as an embodiment of the present invention includes a carbon dioxide gas barrier film layer 11 having transparency, a printing ink layer 12 whose color tone changes depending on the presence or absence of carbon dioxide gas, an adhesive layer 16, and a carbon dioxide gas barrier. A laminated body 10 (see FIG. 1A) in which a layer 14 and an adhesive layer 15 are sequentially laminated is sealed with an adhesive layer 16 at the peripheral edge s, and the printing ink layer 12 is enclosed. (See FIG. 1B).

  The adhesive layer 16 for sealing the peripheral edge of the laminate 10 is formed on the peripheral edge s of the carbon dioxide gas barrier film layer 11 in the stacking process of the laminate.

  As described above, the tamper-proof label 10 ′ is in a region where the peripheral edge s of the laminate 10 is sealed with the adhesive layer 16 and the printing ink layer 12 is surrounded by the sealing portion of the peripheral edge. The printing ink layer 12 whose color tone changes depending on the presence or absence of carbon dioxide gas is sealed with the adhesive layer 16 while maintaining the color tone in a carbon dioxide atmosphere. It must be present in the area surrounded by the part. As a method of enclosing the printing ink layer 12 in such a state, after printing the printing ink layer 12 by bubbling carbon dioxide in an ink composition whose color tone changes depending on the presence or absence of carbon dioxide, the laminating step, sealing After the stopping step, it is possible to adopt a method of enclosing while maintaining the color tone in a carbon dioxide gas atmosphere.

In addition, a tamper-proof label 20 ′ shown as another embodiment of the present invention includes a transparent carbon dioxide gas barrier film layer 21, a heat-sealable resin layer 27, and a printing ink whose color tone changes depending on the presence or absence of carbon dioxide gas. A layered body 20 (see FIG. 2B) in which the layer 22, the heat-sealable resin layer 27, the carbon dioxide gas barrier layer 24, and the adhesive layer 25 are sequentially laminated is a pair of heat at the peripheral edge. The resin layers 27 and 27 that can be sealed are sealed, and the printing ink layer 22 is enclosed.

  Similarly to the tamper-proof label 10, the tamper-proof label 20 ′ has a pair of heat-sealable resin layers 27 while the printing ink layer 22 whose color tone changes depending on the presence or absence of carbon dioxide gas maintains the color tone in a carbon dioxide gas atmosphere. , 27 is enclosed in a region surrounded by a portion sealed at the peripheral edge thereof.

  The sealing at the peripheral edge by the heat-sealable resin layers 27, 27 can be performed by a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, an ultrasonic seal, and the like. .

For example, as shown in FIG. 3, the tamper-proof label having such a configuration is used by sticking over the lid K ₁ and the side wall K _{2 of} the packaging body 40 that contains a medicine or the like (FIG. 3A )reference). At this time, the printing ink layer 12 whose color tone changes depending on the presence or absence of carbon dioxide gas is enclosed and enclosed by the carbon dioxide gas barrier film layer 11 and the carbon dioxide gas barrier layer 14 which are impermeable to carbon dioxide gas, as described above. It is in a state filled with carbon dioxide.

Then, when cut along the boundary line L between the lid K ₁ and the side wall K ₂ with a sharp blade, the carbon dioxide trapped in the label is released and the color tone of the printing ink layer 12 ′ is carbon dioxide. It changes from the color tone under the atmosphere to the color tone under the air exposure condition (see FIG. 3B). Therefore, since the change in color tone can be easily recognized, it can be easily and reliably identified whether or not it has been opened, and it is determined that an attempt has been made to illegally peel off what has been stuck on the packing body, etc. This makes it possible to prevent mischief, tampering, unloading and the like.

  Hereinafter, the base material and material which comprise the tamper-proof label of this invention are demonstrated in detail.

  As the carbon dioxide gas barrier film having transparency constituting the carbon dioxide gas barrier film layers 11 and 21 having transparency used in the present invention, for example, a film made of polyvinylidene chloride coated substrate, EVOH, PVA, barrier Ny, etc. Is used.

  A gas barrier film disclosed in JP-A-11-129384 can also be used. That is, a barrier film in which a deposited thin film layer made of an inorganic oxide such as aluminum oxide, silicon oxide, magnesium oxide or a mixture thereof is formed on a base material made of a transparent plastic material can be used. In the barrier film having such a structure, a transparent primer layer is laminated on a base material made of a transparent plastic material, and a gas barrier coating layer is further laminated on a vapor-deposited thin film layer made of an inorganic oxide, if necessary. May be. Hereinafter, the structure of this gas barrier film will be described in some ways.

  Examples of the substrate made of the above transparent plastic material include, for example, polyester films made of polyethylene terephthalate, polyethylene naphthalate, etc., polyolefin films made of polyethylene, polypropylene, etc., polystyrene films, polyamide films, polyvinyl chloride films, polycarbonate films, An acrylonitrile film, a polyimide film, etc. are used. These films may be either stretched or unstretched, but those having excellent mechanical strength and dimensional stability are preferably used. Among these, a polyethylene terephthalate film arbitrarily stretched in the biaxial direction is preferably used. Further, a thin film may be provided on the surface of these films with various well-known additives and stabilizers, for example, an antistatic agent, an anti-ultraviolet agent, a plasticizer, a lubricant, and the like. In order to improve the properties, corona treatment, low temperature plasma treatment, ion bombardment treatment, chemical treatment, solvent treatment and the like may be performed as pretreatment.

  The optimum condition of the thickness of the vapor-deposited thin film layer varies depending on the type and configuration of the inorganic oxide used, but it is generally desirable that the thickness be in the range of 5 to 300 nm. However, if the thickness is less than 5 nm, it may be difficult to obtain a uniform film or the film thickness may not be sufficient, and the function as a gas barrier material may not be sufficiently achieved. If the thickness exceeds 300 nm, it becomes difficult to maintain flexibility in the thin film, and if an external force such as bending or pulling is applied after the film formation, the thin film may be cracked. The thickness of the deposited thin film layer is preferably in the range of 10 to 150 nm.

  There are various methods for forming a vapor-deposited thin film layer made of an inorganic oxide, but usually it can be formed by a vacuum vapor deposition method. Other thin film forming methods such as sputtering, ion plating, and plasma vapor deposition (CVD) can also be used. However, considering productivity, the vacuum deposition method is the best at present. As the heating means of the vacuum deposition apparatus by the vacuum deposition method, the electron beam heating method, the resistance heating method, and the induction heating method are preferable. In order to improve the adhesion between the thin film and the substrate and the denseness of the thin film, a plasma assist method or an ion It is also possible to use a beam assist method. In addition, in order to increase the transparency of the deposited thin film, it is possible to adopt reactive vapor deposition in which oxygen gas or the like is blown during vapor deposition.

A transparent primer layer formed on a substrate made of a transparent plastic material can be represented by the general formula R′Si (OR) ₃ (R ′: alkyl group, vinyl group, glycidoxypropyl group, R: alkyl group, etc.). A trifunctional organosilane or a hydrolyzate of the organosilane, and a composite of an acrylic polyol and an isocyanate compound can be formed by a coating solution obtained by dissolving in a solvent. Although the thickness of a transparent primer layer will not be specifically limited if a coating film can be formed uniformly, Generally it is preferable that it is the range of 0.01-2 micrometers. When the thickness is less than 0.01 μm, it is difficult to obtain a uniform coating film, and the adhesion may be lowered. On the other hand, when the thickness exceeds 2 μm, it is difficult to maintain the flexibility of the coating film, and it is not preferable because the coating film may be cracked by applying force accompanying bending or pulling. Particularly preferred is a range of 0.05 to 0.5 μm. As a method for forming such a transparent primer layer, for example, a known printing method such as an offset printing method, a gravure printing method, a silk screen printing method, or a known coating method such as a roll coat, a knife edge coat, or a gravure coat is used. Can be used.

  The gas barrier coating layer formed on the vapor-deposited thin film layer made of an inorganic oxide is provided for imparting a gas barrier property as high as that of an aluminum foil. The gas barrier coating layer is made of, for example, an aqueous solution or a water / alcohol mixed solution containing at least one of a water-soluble polymer and (a) one or more metal alkoxides and hydrolysates or (b) tin chloride. It is formed using a coating agent. More specifically, a solution in which a water-soluble polymer and tin chloride are dissolved in an aqueous (water or water / alcohol mixed) solvent, or a treatment in which a metal alkoxide is directly or previously hydrolyzed. It is formed by coating a thin film of a solution mixed with the above on a vapor-deposited thin film layer made of an inorganic oxide and heating and drying. As a method for applying the coating agent, conventionally known means such as a dipping method, a roll coating method, a screen printing method, a spray method and the like which are usually used can be used. The thickness of the coating film varies depending on the type of coating agent and the processing conditions, but it is sufficient that the thickness after drying is 0.01 μm or more. However, if the thickness exceeds 50 μm, cracks tend to occur in the coating film. A range of 01 to 50 μm is preferable.

Next, the ink composition constituting the printing ink layers 12 and 22 whose color tone changes depending on the presence or absence of carbon dioxide gas will be described. As this ink composition, an ink composition containing a variable color pigment composition whose color tone changes with or without carbon dioxide gas is used. The variable color pigment composition mainly comprises a pH indicator, a binder, and a solvent, and the color tone that is clearly changed between the atmosphere and the carbon dioxide gas atmosphere, and the color tone change can be visually recognized. It is.

  Any pH indicator can be used as long as it undergoes a change in color tone due to the influence of carbon dioxide. For example, bromocresol green, methyl red, chlorophenol red, bromocresol purple, bromothymol blue, neutral red, phenol red, cresol red, α-naphtholphthalein, curcumin, metacresol purple, ethylbis (2,4-dinitrophenyl) ) Acetate, thymol blue, p-xylenol blue, phenolphthalein and the like. A particularly preferred pH indicator is metacresol purple because it is easy to understand changes in safety and color reaction.

  An alkaline substance can be preferably added to the ink composition at a ratio of 5% by weight or less. Even if an alkaline substance exceeding 5% by weight is added, the effect is equivalent and uneconomical.

  As the alkaline substance, for example, an appropriate one can be selected from organic alkalis such as triethanolamine and polyethyleneimine, and alkali hydroxides, alkali carbonates, alkali hydrogen carbonates, ammonia, and the like.

  As the solvent, a solvent that can uniformly and stably dissolve or disperse the above-described components of the ink composition is selected. Specific examples include ethers, aromatic hydrocarbons, esters, alcohols, and ketones. Of these, alcohols are preferred. Further, in order to dissolve a pigment, an alkaline substance or the like to obtain an ink composition and to obtain a good color as an indicator, it is preferable to include water. The ratio of the solvent such as alcohol and water is preferably about 2 parts by weight with respect to 1 part by weight of water. If the amount of water added is less than 1 part by weight, sufficient color development may not be obtained and the change in color tone may not be discriminated. Moreover, when water exceeds 1 weight part, the external appearance defect may generate | occur | produce on high-humidity conditions.

  In addition, as a binder, it is used for fixing a component such as a pH indicator on a portion to be printed, and a resin that swells or dissolves in water after forming an ink film is not suitable. Therefore, a resin that retains water is used. Examples of such a binder include polyacrylic acid, polyvinyl alcohol, polyvinyl butyral, polyvinyl acetal, polyvinyl acetate, polyurethane, and partially saponified vinyl acetate.

  The ink composition whose color tone changes depending on the presence or absence of carbon dioxide gas preferably further contains a polyhydric alcohol. The polyhydric alcohol acts as a humectant, and can hold a solvent such as water in the printing ink layer serving as the color tone changing portion to facilitate the absorption of carbon dioxide gas and promote the color reaction of the pH indicator.

  As the polyhydric alcohol, glycerin, ethylene glycol, propylene glycol, polyethylene glycol and the like can be used. Among these, glycerin is more preferably used. These polyhydric alcohols are preferably contained in the ink composition at about 1 wt% to 10 wt%. When the ratio of the polyhydric alcohol is less than 1% by weight, the color development speed tends to be insufficient. On the other hand, even if the ratio of polyhydric alcohol exceeds 10% by weight, the effect does not change.

  The tamper-proof label of the present invention can not only determine the presence / absence of cutting / opening by the change in color tone of the pH indicator itself, but also enable determination of cutting / opening by the change in color tone due to color mixing with other color pigments. it can. For this purpose, a desired colorant can be added to the ink composition whose color tone changes depending on the presence or absence of carbon dioxide gas.

  When a colorant is added and mixed with the color of the ink composition whose color tone changes depending on the presence or absence of carbon dioxide gas, for example, it is difficult to visually determine the color change of the indicator itself, or the color tone is not preferable in design Sometimes, it can be changed to a color tone that is easy to visually judge, or a color tone that is preferable in design.

  Further, in order to improve the coating properties of the ink composition, various agents such as surfactants, varnishes, compounds, drying inhibitors, as long as they do not affect the color development of the printing ink layer whose color tone changes depending on the presence or absence of carbon dioxide gas, It is also possible to add a dryer or the like.

  On the other hand, examples of the heat-sealable resin constituting the pair of heat-sealable resin layers 27 and 27 include resins that can be melted by heat and fused to each other.

  Specifically, low density polyethylene, medium density polyethylene, high density polyethylene, linear (linear) low density polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene -Methacrylic acid copolymer, ethylene-methyl methacrylate copolymer, ethylene-propylene copolymer, methylpentene polymer, polybutene polymer, polyolefin resin such as polyethylene or polypropylene, acrylic acid, methacrylic acid, maleic acid, maleic anhydride An acid-modified polyolefin resin modified with an unsaturated carboxylic acid such as acid, fumaric acid or itaconic acid, a polyvinyl acetate resin, a poly (meth) acrylic resin, a polyvinyl chloride resin or the like can be used.

  The heat-sealable resin layer 27 may be formed by applying a heat-sealable resin as described above, or may be formed by laminating a film or sheet made of the heat-sealable resin as described above. . The thickness of the heat-sealable resin layer 27 can be set within a range of about 5 to 300 μm, preferably 10 to 100 μm.

The adhesive layer 16 is, for example, polyurethane, polyester, polyamide, epoxy, poly (meth) acrylic, polyvinyl acetate, polyolefin, casein, wax, ethylene- (meth) acrylic acid copolymer, It can be formed using a solvent-based or solvent-free adhesive mainly composed of a polybutadiene-based vehicle or the like. The adhesive layer can be formed by, for example, coating a thin film made of an adhesive with a roll coat, gravure coat, knife coat, deb coat, spray coat, or other coating method, and then removing the solvent and diluent in the thin film by drying. Can be done. The application amount of this adhesive is preferably about 0.1 to 5 g / m ² (dry state).

  Examples of the method for sealing the peripheral edge of the laminate 10 constituting the tamper-proof label through the adhesive layer 16 include printing, in-line, and dry laminating methods. In this method, printing and dry laminating are performed with the same device (inline), and a printing / inline / dry laminating machine consisting of a printing unit, an adhesive coating unit, and a bonding part is used to apply the adhesive. In this method, an adhesive layer is patterned on the peripheral edge of the carbon dioxide gas barrier film by a plate to be processed and provided by printing, and this portion is adhered to the carbon dioxide gas barrier layer 14 facing the portion.

Moreover, as a method of sealing the peripheral edge of the laminate 20 constituting the tamper-proof label by heat sealing, a method of patterning a heat roll according to the label shape and heat-sealing only on the planned cutting line, There is a method of sealing using a heat seal bar. FIG. 5 shows a method in which the peripheral edge is heat sealed using a heat seal bar, and after sealing in the vertical direction, the horizontal direction is sealed. Such a heat sealing method can be carried out by modifying a normal bag making machine.

  Furthermore, the carbon dioxide gas barrier layers 14 and 24 may be transparent or opaque, and are not particularly limited as long as they have carbon dioxide gas barrier properties. Specifically, it can be composed of a metal foil such as an aluminum foil, a resin film such as polyvinylidene chloride having a barrier property against carbon dioxide, polyvinyl alcohol, saponified ethylene-vinyl acetate copolymer, or the like.

  Further, the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layers 15 and 25 is not particularly limited, but for example, natural rubber-based pressure-sensitive adhesives, synthetic rubber-based pressure-sensitive adhesives, acrylic pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives and the like. To various pressure-sensitive adhesives generally used for pressure-sensitive adhesive labels and pressure-sensitive adhesive tapes. In these, an acrylic adhesive is used suitably.

  As the acrylic pressure-sensitive adhesive, for example, an acrylic ester homopolymer, a copolymer containing two or more acrylic ester units, and a copolymer of an acrylic ester and another functional monomer are used. What contains at least 1 sort (s) chosen from the inside is used.

  Examples of acrylic acid esters include (meth) acrylic acid butyl ester, (meth) acrylic acid pentyl ester, (meth) acrylic acid hexyl ester, (meth) acrylic acid heptyl ester, (meth) acrylic acid octyl ester, (meth) Examples include acrylic acid nonyl ester, (meth) acrylic acid decyl ester, and the like. Examples of the functional monomer include hydroxyl group-containing monomers such as (meth) acrylic acid hydroxyethyl ester and (meth) acrylic acid hydroxypropyl ester, and amides such as (meth) acrylamide and dimethyl (meth) acrylamide. Examples thereof include group-containing monomers and carboxylic acid group-containing monomers such as (meth) acrylic acid. In addition, if necessary, other monomers copolymerizable with the acrylate ester, for example, vinyl acetate, styrene, acrylonitrile, etc. may be copolymerized.

  Such a pressure-sensitive adhesive may contain a tackifier, a crosslinking agent, a filler and the like as necessary. Examples of the tackifier include natural resins such as rosin resins and polyterpene resins, and synthetic resins such as petroleum resins, coumarone indene resins, and xylene resins.

  The type of the pressure-sensitive adhesive is not particularly limited, and may be any type such as a solvent-type pressure-sensitive adhesive, a non-aqueous dispersion-type pressure-sensitive adhesive, an emulsion-type pressure-sensitive adhesive, and a dispersion-type pressure-sensitive adhesive. In addition, as a method of forming an adhesive layer using this adhesive, a general coating machine such as a roll coater, a comma coater, a die coater, a hot melt coater, or the like was used to apply directly to a predetermined formation portion. Thereafter, a so-called direct coating method in which an adhesive layer is formed may be adopted, or a coating is applied on a separator to form an adhesive layer, which is then transferred to a predetermined surface of a substrate. A method may be adopted.

The coating amount of the adhesive at that time is not particularly limited, but is preferably 5 to 100 g / m ² in terms of solid content. If the coating amount of the adhesive is less than 5 g / m ² , sufficient tack and adhesive strength may not be obtained. Conversely, if it exceeds 100 g / m ² , the holding power and creep resistance may be reduced. There is.

In addition, in the above coating, in order to further improve the adhesion (anchor property) with the formation surface of the adhesive layer, the formation surface may be subjected to surface oxidation treatment such as corona discharge, for example, modified natural rubber. An undercoat layer (primer layer) such as a system or a synthetic rubber system may be provided in advance.

  On the other hand, the printing ink layer whose color tone changes depending on the presence or absence of carbon dioxide gas is applied by a normal printing method as a desired printing pattern such as a character, a figure, a symbol, a pattern, or a pattern.

  Further, in the laminate constituting the tamper-proof label of the present invention, as a method of laminating a transparent carbon dioxide barrier film, a heat-sealable resin film, and a carbon dioxide barrier film, a method of laminating a normal packaging material, For example, a wet lamination method, a dry lamination method, a solventless dry lamination method, an extrusion sand lamination method, or the like can be used.

  In the tamper-proof label of the present invention thus obtained, the printing ink layer that changes in color tone with a chemical reaction depending on the presence or absence of carbon dioxide gas is confined between the carbon dioxide gas barrier film layer and the carbon dioxide gas barrier layer. Carbon dioxide impervious label. Therefore, when the tamper-proof label is stuck and sealed across the lid and side wall of the package containing medicines, etc., when cut and opened with a sharp blade, carbon dioxide escapes from the label layer, The color tone presented under the carbon dioxide atmosphere will change to the color tone under atmospheric exposure, and the color change can be easily visually recognized, so it can be easily and reliably identified whether or not it has been opened. . Thus, according to the tamper-proof label of the present invention using a chemical reaction that is not easily affected by the use environment, regardless of physical tamper-proof means, it is easy to find malicious opening of the package, mischief, tampering, Unloading and the like can be prevented.

It is explanatory drawing which shows the structure of the tamper-proof label of this invention. It is explanatory drawing which shows the structure of the other tamper-proof label of this invention. It is explanatory drawing which shows the use condition of the tamper-proof label of this invention. It is explanatory drawing which shows an example of the method of sealing the peripheral edge part of the laminated body which comprises the tamper-proof label of this invention. It is explanatory drawing which shows the other example of the method of sealing the peripheral edge part of the laminated body which comprises the tamper-proof label of this invention. It is explanatory drawing which shows the general | schematic cross-section structure of the conventional adhesive label for tampering prevention. It is explanatory drawing which shows the general | schematic cross-section structure of the conventional tamper-proof label. It is explanatory drawing which shows the state when the conventional tamper-proof label use state and a label are cut | disconnected with a cutter.

Explanation of symbols

10, 20 ... Laminate 50, 60 ... Tamper-proof label 10 ', 20' ... Carbon dioxide impermeable tamper-proof label 11, 21 ... Carbon dioxide gas barrier film layer 12 having transparency, 22 ... printing ink layer 12 'whose color tone changes depending on the presence or absence of carbon dioxide gas ... printing ink layer 14, 24 ... carbon dioxide gas barrier layers 15, 25 ... adhesive layer whose color tone changes due to a decrease in carbon dioxide concentration 16 ... adhesive layer 27 ... heat-sealable resin layer 40, K ... packing body 40 'with tamper-proof label attached, K' ... packing body K1 with cut label ... Lid K2 ... Side wall L ... Lid and side wall 51 of package body ... Label base materials 52, 52 (1), 52 (2), 52 (3) ... Easy peeling layer 53 ... Printing ink layer 54 ... Adhesive layer 55 ... Adhesive layer base 56 the adhesive strength between the ... removable pressure-sensitive adhesive layer 57 ... removable following adhesive layer 58 ... adherend X _AB ... label substrate and the peelable layer X _BC ... Adhesive strength X between the easily peelable layer and the ink layer X _AC: Adhesive strength X between the label substrate and the ink layer X _CD: Adhesive strength X between the ink layer and the releasable followable adhesive layer X _D : Adhesive strength between re-peelable adhesive layer and adherend X _B : Fracture strength S _AB inside easy peelable layer S _AB ... Interface between label substrate and easy peelable layer between S _BC · · · peelable layer and the surface S _CD · · · ink layer and the removability following adhesive layer between the surface S _AC · · · label base material and the ink layer between the ink layer Interface _SD : Interface Yab between re-peelable followable adhesive layer and adherend Adhesive strength Yac between adhesive layer substrate and adhesive layer ... Adhesive layer substrate and re-peelable type Between the adhesive layer Adhesive strength 61 ... base material 62 ... curl film 623 ... upper material film 624 ... lower material film 621 ... both side parts (adhesion part)
622 ... Central part (non-adhesive part)
6220: Cut end B1, B2, B3 of the curl film: adhesive layer f: tension tension

Claims (3)

  At least the laminated body in which the carbon dioxide gas barrier film layer having transparency, the printing ink layer whose color tone changes depending on the presence or absence of carbon dioxide gas, the carbon dioxide gas barrier layer, and the adhesive layer are laminated in this relative order. A tamper-proof label characterized in that the label is sealed at the end and the printing ink layer is sealed.   An adhesive layer for bonding the carbon dioxide gas barrier film layer having transparency and the carbon dioxide gas barrier layer is provided at the peripheral edge of the laminate, and the peripheral edge of the laminate is sealed by the adhesive layer. The tamper-proof label according to claim 1, wherein the tamper-proof label is provided.   In the laminate, a pair of heat-sealable resin layers are laminated so as to be sandwiched between a transparent carbon dioxide barrier film layer and a carbon dioxide gas barrier layer, and the periphery of the laminate is formed by the pair of heat-sealable resin layers. The tamper-proof label according to claim 1, wherein the end is sealed.