JP6273899B2 - Fraud detection labels and labeled items - Google Patents

Description

  The present invention relates to a fraud detection label and an article with a label to which the fraud detection label is attached.

The forgery prevention medium is used to prevent forgery of securities, branded products, certificates, personal authentication media, and the like, and has a function of proving that it is a genuine product.
In recent years, since special optical effects can be distinguished at a glance, forgery prevention structures using optical elements such as diffraction gratings and holograms and special inks are used for various articles. The anti-counterfeit structure is manufactured in the form of an anti-counterfeit film, an anti-counterfeit sticker, an anti-counterfeit transfer foil, or the like, and is used by being attached to securities, brand products, certificates, personal authentication media, and the like.

Many of these pasted anti-counterfeit structures have been subjected to measures for detecting fraud such as tampering and reuse.
For example, Patent Document 1 proposes an anti-counterfeit sticker having a solvent coloring layer that develops color when the sticker is peeled off with various solvents.
Moreover, in patent document 2, it has the peelable adhesive sheet for concealing a volume hologram layer, and the adhesive for adhere | attaching a volume hologram layer to a to-be-adhered body, The peeling strength between each laminated | stacked layers By adjusting the volume hologram layer, the volume hologram layer can be visually observed by re-peeling the label after bonding to the adherend, and the volume hologram layer having a volume hologram layer that cohesively breaks when attempting to peel the volume hologram layer. Labels have been proposed.

  Further, Patent Document 3 proposes a hologram brittle seal in which a hologram layer or the like is laminated on a substrate that has been partially surface-treated to improve adhesion, and the hologram layer is partially peeled and broken when peeling is attempted. Has been.

JP 2009-134528 A Japanese Patent No. 4097128 Japanese Patent No. 3684653

However, in the sticker of Patent Document 1, when the solvent coloring layer does not react, for example, when a solvent having a solubility parameter (hereinafter also simply referred to as SP value) that is greatly different from the coloring material is selected and peeled off, the sticker is peeled off by the solvent. Since there is no remaining history, there remains a problem that stickers are reused illegally.
In addition, the labels and seals of Patent Document 2 and Patent Document 3 provide a sufficient effect when physical peeling is attempted, but the effect is sufficient for the method of dissolving the adhesive layer using a solvent. is not.

  The present invention has been made paying attention to the above circumstances, and it is an object of the present invention to provide a fraud detection label that can easily detect fraud when an attempt is made to peel off with a solvent in a state of being affixed to an article. And

The fraud detection label according to the first aspect of the present invention is made of a material that changes its color when dissolved in a first solvent having a solubility parameter (SP value) of 11 [(cal / cm ³ ) ^1/2 ] or less. A solvent color detection layer, and an optical change layer made of a material that dissolves in a second solvent having a solubility parameter (SP value) of 11 [(cal / cm ³ ) ^1/2 ] or more, and the optical change layer Includes a first resin having a first number average molecular weight and a second resin having a second number average molecular weight, which is dissolved in the second solvent, and exhibits a first visible light transmittance. The first number average molecular weight is 5 times or more of the second number average molecular weight, and the optical change layer includes the second resin and the second resin. When in contact with the solvent, the transmittance is higher than the first visible light transmittance at the portion where the second solvent is in contact. Characterized in that had become the second of the second optical state of the visible light transmittance.

  According to a second aspect of the present invention, there is provided a labeled article, wherein the fraud detection label according to the first aspect is pasted through an adhesive layer.

According to the fraud detection label of the present invention, when peeling with a solvent is attempted in a state where the fraud detection label is attached to an article, the optical state of at least a part of the solvent color detection layer or the optical change layer changes. Thus, it is possible to easily detect that an attempt has been made to peel off with a solvent, and thus a label that can prevent reuse and tampering is provided.
At this time, since the number average molecular weights of the first resin and the second resin are greatly different, the change in the optical state is likely to appear in the mottled pattern state, so that the change in the optical state is more easily detected. .

It is the top view which looked at the fraud detection label concerning a 1st embodiment of the present invention from the front side. It is AA sectional drawing in FIG. It is the top view which looked at the example of the state after immersing the fraud detection label concerning a 1st embodiment in solvent A which is the 1st solvent, and making it dry from the front side. It is the top view which looked at the example of the state after immersing the fraud detection label concerning a 1st embodiment in solvent B which is the 2nd solvent, and making it dry from the front side. It is the top view which looked at the fraud detection label which concerns on 2nd Embodiment of this invention from the front side. It is BB sectional drawing in FIG. It is the top view which looked at the example of the state after immersing the fraud detection label concerning a 2nd embodiment in solvent A which is the 1st solvent, and making it dry from the front side. It is the top view which looked at the example of the state after immersing the fraud detection label concerning a 2nd embodiment in solvent B which is the 2nd solvent, and making it dry from the front side.

“First Embodiment”
The fraud detection label according to the first embodiment of the present invention will be described below with reference to the drawings as appropriate.
In addition, the same referential mark is attached | subjected to the component which exhibits the same or similar function through all the drawings, and the overlapping description is abbreviate | omitted.
As shown in FIGS. 1 and 2, the fraud detection label 10 of the first embodiment includes a label substrate 2, and the optical change layer 1, the print layer 4, and the one surface (front side) of the label substrate 2. Are partially provided, and the solvent color detection layer 3 and the adhesive layer 5 are provided on the other surface (adhesion side) of the label base material 2, respectively.

In the example of the first embodiment, as shown in FIG. 2, the fraud detection label 10 is laminated in the order of the adhesive layer 5, the solvent color detection layer 3, and the label base material 2, and the surface of the label base material 2 is optically The change layer 1 and the print layer 4 are formed and configured. However, the optical change layer 1, the printing layer 4, and the solvent color detection layer 3 are not necessarily provided so as to be in direct contact with the label base material 2, and are illustrated between the base material 2 and the respective layers 1, 4, 3. An intermediate layer or the like may be provided.
Here, in the following description, a solvent having an SP value of 11 or less is referred to as a solvent A (first solvent), and a solvent having an SP value of 11 or more is referred to as a solvent B (second solvent). The solvent A and the solvent B are solvents that can dissolve or swell the adhesive layer 5.

(Label substrate)
The label substrate 2 is preferably made of a film or paper, for example, a plastic film such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), paper, synthetic paper, plastic multilayer paper or Resin-impregnated paper, paperboard, cardboard, metallized paper, and thermal transfer paper can be used. However, it is preferable to use a material that has little chemical and physical deformation or alteration due to heat, pressure, solvent, or the like applied when the optical change layer 1, the print layer 4, or the solvent color detection layer 3 is provided.

  The thickness of the substrate 2 is preferably 40 μm or more and 200 μm or less. When the thickness is 40 μm or more, the physical strength as a label is sufficient and easy to handle. On the other hand, when the thickness is 200 μm or less, detection by solvent coloring when illegal re-peeling with the solvent is performed due to the penetration of the solvent. Becomes easier. A more preferable thickness of the base sheet is 50 μm or more and 120 μm or less.

(Optical change layer)
The optical change layer 1 includes a first resin and a second resin, which are two types of resins having greatly different number average molecular weights, at a predetermined ratio. The optical change layer 1 may contain a resin other than the first resin and the second resin.
The first resin has a first number average molecular weight, the second resin has a second number average molecular weight, and the first number average molecular weight is set to 5 times or more of the second number average molecular weight. Has been. The optical change layer 1 is in a first optical state showing a first visible light transmittance in a normal state (a state immediately after the production of the label and not in contact with the solvent B) (FIG. 1).

  The first resin and the second resin are resins that dissolve by being in contact with the solvent B, and the optical change layer 1 is in contact with the solvent B that can dissolve the first and second resins, and then the solvent B As shown in FIG. 4, the region 7 in contact with is configured to be in a second optical state that exhibits a second visible light transmittance lower than the first visible light transmittance. Here, from the viewpoint of visual recognition, the second visible light transmittance is preferably set to be a visible light transmittance value that is reduced by 5% or more from the first visible light transmittance.

That is, the optical change layer 1 contains the first resin and the second resin in such a ratio that when the optical change layer 1 comes into contact with the solvent B, the optical change layer 1 changes from the first optical state to the second optical state. Here, the solvent B that can dissolve the first and second resins corresponds to a solvent that can dissolve or swell the adhesive layer 5 so that the label 10 can be peeled from the article in the adhesive layer 5.
Thus, after the optical change layer 1 (FIG. 1) in the first optical state of the fraud detection label 10 comes into contact with the solvent B that can dissolve the first and second resins, the optical change layer 1 The region 7 (FIG. 4) in the second optical state is locally generated in the region, the visible light transmittance in both optical states is different by 5% or more, and the number average molecular weights of the first resin and the second resin are Due to the large difference, the mottle pattern is easily observed by visual observation in the region 7 of the optical change layer 1 after contact with the solvent B.

A more effective aspect is a state in which the first optical state is transparent to visible light and the second optical state is opaque. That is, it is an aspect in which the first and second resins change from a compatible state to an incompatible (incompatible) state by contacting the solvent B. In addition, you may make the transmittance | permeability low by containing another resin.
Here, the first resin and the second resin are “compatible” means that a mixed resin solution obtained by dissolving or dispersing a mixed resin of the first resin and the second resin in an organic solvent, or the The mixed resin solid substance obtained by drying the mixed resin solution has a light scattering property and is transparent. The visual turbidity method is simple and reliable for determining whether the mixed resin solution or the mixed resin solid is compatible or incompatible. For example, when the mixed resin solution containing the first resin and the second resin is transparent, or when the film prepared by drying the mixed resin solution is transparent, it is determined that both resins are compatible. it can.

  In the case of visual observation, in the present embodiment, the resolution of the human eye is considered to be about the wavelength of visible light (about 500 nm). That is, when transparent, it is guaranteed that the concentration and composition are uniform, that is, compatible even at wavelengths longer than the visible light wavelength. On the other hand, when the mixed resin solution or the mixed resin solid is opaque, it is determined that the sample is incompatible. The reason for becoming opaque is that the concentration and composition are not uniform due to the incompatibility of the first resin and the second resin.

  When the optical change layer 1 is formed in a state where the first resin and the second resin are compatible, that is, when the optical change layer 1 is formed in a state transparent to visible light, The optical change layer 1 comes into contact with the solvent B in an attempt to peel the label 10 from the article using the solvent B, and in the process of volatilization of the solvent, the first resin and the second resin are locally formed in the optical change layer 1. The balance of the blending ratio with the resin is lost, and both resins shift to an incompatible state, become opaque in the local region, and a mottled pattern appears as a whole.

That is, since the number average molecular weight of one of the first and second resins is 5 times or more of the other number average molecular weight, the dissolution rate of each resin with respect to the solvent B is greatly different, so that a mottled pattern is easily developed. .
In a preferred embodiment, the ratio of the first resin to the total mass of the first resin and the second resin (the content (% by mass) of the first resin) is based on the mass, and these mixed resins are compatible with each other. The range from the first boundary content C1 (%) to (C1-10) (%) that changes from compatible to incompatible when the content is increased from the soluble content to the incompatible content Preferably, these mixed resins are in the range from the second boundary content C2 (%) to (C2 + 10) (%) where the mixed resin changes from incompatible to compatible.

The first number average molecular weight is preferably 10,000 to 100,000, and the second number average molecular weight is preferably 50,000 to 500,000.
Specifically, for example, Toa Gosei Co., Ltd. “ARUFON UC-3910” acrylic resin (number average molecular weight of 8,000,000) can be used as the first resin.
As the second resin, for example, a cellulose derivative such as alcohol-soluble nitrocellulose resin (number average molecular weight 70,000) manufactured by Nobel NC may be used.

Here, the number average molecular weight can be measured by an osmotic pressure method, a viscosity method, a light scattering method, or the like.
Here, the dissolution rate of the resin in a certain organic solvent is mainly determined by the number average molecular weight of the resin, but may also depend on crystallinity, polarity, and SP value (solubility parameter).
In general, a resin material having a high average molecular weight has a low dissolution rate, and a resin material having a low average molecular weight has a high dissolution rate. For example, in the case of a chain polymer (resin), the longer the molecular chain (the higher the average molecular weight), the greater the attractive force between the polymer molecules, making it difficult to disentangle and disperse the molecular chains from the solvent molecules. In addition, the attractive force between polymer molecules increases as the surface where the polymer molecules contact each other, that is, as the polymer molecule orientation is ordered (crystalline). Therefore, in a chain polymer, the higher the average molecular weight (degree of polymerization) and the higher the ratio of crystallinity, the less soluble it in the solvent. For this reason, it is possible to change the optical state in a mottled manner by setting the number average molecular weights of the first resin and the second resin to be greatly different.

  Another factor that determines the solubility of the resin is its affinity with solvent molecules. For example, polar polymers tend to be soluble in polar solvents and tend not to dissolve in nonpolar solvents, and nonpolar polymers tend to be reversed. An SP value δ is a factor for determining the strength of this affinity. This δ value is expressed by the following formula. In principle, the closer the δ value between the polymer and the solvent molecule, the higher the solubility.

δ ² = ΔE / V
Here, ΔE is the evaporation energy and V is the molar volume.
As main δ values [(cal / cm ³ ) ^1/2 ] of the resin material, vinyl acetate (9.1), polymethyl methacrylate (9.2), vinyl chloride (9.3), vinyl acetate (9. 4), nitrocellulose (10.1), methacrylate resin (10.7), cellulose acetate (11), cellulose diacetate (11.4), polystyrene (8.6 to 9.7) and the like are known literatures. It is shown.

  The main δ values of the solvent include isoparaffin (7.3), cyclohexane (8.2), butyl acetate (8.5), toluene (8.9), ethyl acetate (9.1), methyl ethyl ketone (9 .3), tetrahydrofuran (9.5), acetone (10), isopropanol (11.5), ethyl alcohol (12.7), water (23.4) and the like are shown in known literatures.

For example, to increase the dissolution rate in a certain solvent, a resin having a solubility parameter close to that solvent may be selected. Conversely, to decrease the dissolution rate in a solvent, a resin having a solubility parameter different from that of the solvent is selected. do it.
The solvent B that can dissolve the first resin and the second resin is a solvent that can dissolve or swell the adhesive layer 5 so that the label 10 can be peeled from the article in the adhesive layer 5. As such a solvent B, in this embodiment, the methanol (14.5), ethanol (12.7), isopropanol (11.5), n-butanol (11.4) whose SP value is 11 or more. And a solvent such as ethylene glycol 14.1 or a mixture thereof.

  When the fraud detection label 10 is in contact with such a solvent and then dried, the optical change layer 1 changes from the state shown in FIG. 1 to the state shown in FIG. When the label 10 of FIG. 1 before the change is observed from the front side, that is, the observer side, typically, the optical change layer 1 has visible light transmittance, and the surface of the substrate 2 is passed through the optical change layer 1. It can be confirmed visually. On the other hand, when the label 10 of FIG. 4 after the change is observed from the front side, the second optical state region 7 in which the visible light transmittance is reduced by 5% or more is partially formed inside the optical change layer 1, Due to the mottled pattern, it becomes difficult or impossible to partially observe the substrate 2 through the optical change layer 1. That is, it can be easily visually confirmed that the label 10 in FIG. 4 has a clear change compared to the label 10 in FIG.

As shown above, the optically variable layer 1 includes a difference in number average molecular weight between the first resin and the second resin, a resin ratio that is compatible and incompatible, a dissolution rate, crystallinity, polarity, and a solubility parameter. In consideration of the solvent to be targeted, it is necessary to appropriately select a combination of a resin and a solvent that are compatible when the optical change layer 1 is formed and become incompatible when the resin is redissolved with the solvent B.
In addition, although the optical change layer 1 can be formed by well-known printing methods, such as gravure printing, flexographic printing, screen printing, or offset printing, it is not restricted to this.

(Solvent color detection layer)
The solvent color detection layer 3 is made of a material that dissolves in the solvent A having an SP value of 11 or less. When immersed in the solvent A, the solvent color detection layer 3 partially dissolves and colors the adjacent substrate 2 and the like. This layer is provided for detecting re-peeling. The solvent color detection layer 3 is preferably composed of a dye or pigment and a binder that holds the dye or pigment.

  Usually, the solvent color detection layer 3 is provided so as not to be seen by an observer before the solvent is immersed (FIGS. 1 and 2). When the label 10 is immersed in the solvent A, a colored solvent coloring region 6 (FIG. 3) appears on the observer side, and it is possible to easily detect visually that the illegal re-peeling by the solvent has been performed. . When the solvent coloring area 6 is immersed in the solvent A, the solvent A penetrates from the edge of the label and dissolves the dye, pigment or binder constituting the solvent coloring detection layer 3, and the edge or surface observation of the substrate 2 is observed. This is a colored region formed by volatilizing the solvent after transferring the dye or pigment to the user side.

  The pigment or dye used in this embodiment can be used as long as it dissolves in at least the solvent A, but is particularly suitable if it can be dissolved or finely dispersed at a high concentration in the binder to be used. Can be used for Examples of the dye include azo, phthalocyanine, anthraquinone, and quinophthalone materials. Specifically, each color index number such as solvent yellow, disperse yellow, solvent red, disperse thread, solvent blue, and disperse blue can be selected. These dyes may be used alone or in admixture of two or more when producing dye inks of types such as yellow, magenta and cyan.

  In this embodiment, in order to enhance the effect on solvents such as isoparaffinic solvents (SP value around 7.3) that are often used when the label is illegally removed again, the light resistance and the like are excellent. It is preferable to use anthraquinone dyes or pigments that are strong against color and rich in color, and more preferably those that are soluble in an aliphatic hydrocarbon solvent having about 4 to 18 carbon atoms.

Examples of the anthraquinone-based dye include CI Solvent Violet 14, CI Disperse Red 9, CI Solvent Blue 11, CI Solvent Green 3, and the like, which can be selected as appropriate.
In the present embodiment, one type of dye or pigment using the anthraquinone-based material may be used, or two or more types may be used in combination. Alternatively, anthraquinone-based materials and other materials can be used in combination.

The binder used for the solvent color detection layer 3 is used to hold the above dyes and pigments, and a resin material that is easily dissolved in the solvent A is preferably selected. Examples of the binder resin used include acrylic resins such as ethyl acrylate, vinyl resins such as vinyl acetate, polyester resins, and urethane rubber.
As a method for mixing dyes, pigments, and binders, for example, raw material dyes, pigments, and binder resins are mixed with a propeller type stirrer, dissolver, homomixer, ball mill, bead mill, sand mill, two roll mill, three roll mill, and ultrasonic dispersion. Stir and mix using a mixing machine such as a machine, kneader and line mixer. In particular, by selecting a machine capable of kneading at a high shear rate, such as a two-roll mill, a three-roll mill, a twin-screw extruder, or a kneader, an ink with high dispersibility can be easily produced, so that it is preferably used. In addition, the stirring time varies depending on conditions such as the stirring rotation speed, and is, for example, about 30 minutes to 120 minutes. Moreover, when performing the heating conditions in a stirring and kneading | mixing process, as temperature, about 80-250 degreeC is suitable.

(Print layer)
The print layer 4 is a layer that is provided in an arbitrary color and in the form of a pattern such as a character or a picture, in order to give information to be transmitted.
The printing layer 4 is formed using, for example, ink. As this ink, offset ink, letterpress ink, gravure ink and the like can be used depending on the printing method, and for example, resin ink, oil-based ink and water-based ink can be used depending on the difference in composition. Further, depending on the difference in the drying method, for example, an oxidation polymerization type ink, a permeation drying type ink, an evaporation drying type ink, and an ultraviolet curable ink can be used.

Moreover, as the printing layer 4, you may use the functional ink from which a color changes according to the illumination angle or observation angle of light. Examples of such functional inks include optically variable ink, color shift ink, and pearl ink.
Alternatively, the printing layer 4 may be formed by electrophotography using toner. In this case, for example, a toner in which colored particles such as graphite and pigment are attached to plastic particles having charging properties is prepared, and the toner is transferred to a substrate using static electricity due to charging, and then heated and fixed. By doing so, the printed layer 4 can be formed.
Further, a diffractive structure forming layer or a holographic image forming layer may be provided as the printing layer 4 to give information by diffracted light or a hologram image.

(Adhesive layer)
The adhesive layer 5 is a layer provided for attaching the label 10 to an article. The adhesive layer 5 can be formed of an adhesive mainly composed of, for example, a polyester resin, a urethane resin, an acrylic resin, or a vinyl chloride resin. Moreover, an adhesiveness imparting agent, a filler, a softening agent, a heat-light stabilizer, an antioxidant and the like can be blended as necessary. Examples of the adhesion-imparting agent include rosin resins, terpene phenol resins, terpene resins, aromatic hydrocarbon-modified terpene resins, petroleum resins, coumarone-indene resins, styrene resins, phenol resins, xylene resins, and the like. Examples of the filler include zinc white, titanium oxide, silica, calcium carbonate, and barium sulfate. Examples of the softener include process oil, liquid rubber, and plasticizer. Examples of the thermal light stabilizer include benzophenone, benzotriazole, and hindered amines, and examples of the antioxidant include anilide, phenol, phosphite, and thioester.

  In the present invention, the method for providing the adhesive layer 5 is not limited. For example, a coating machine such as a roll coater, a knife coater, a roll knife coater, an air knife coater, a die coater, a bar coater, a gravure coater, or a curtain coater is used. Then, after applying the adhesive on the release material in advance and bonding it to the back surface of the base sheet after drying, a method of removing the release material and providing the adhesive layer 5 can be mentioned. The thickness of the adhesive layer 5 thus formed is appropriately selected depending on the application, but is usually about 1 to 300 μm, preferably 5 to 100 μm.

(Effects etc.)
As described above, by providing the solvent color detection layer 3 made of a material soluble in the solvent A and the optical change layer 1 made of a material soluble in the solvent B in one label, the solvent color detection layer 3 does not dissolve. It becomes a fraud detection label which can detect with respect to more types of solvents including the solvent which has the SP value which the solvent which has SP value, and the optical change layer 1 does not melt | dissolve.

“Second Embodiment”
Next, a second embodiment will be described with reference to the drawings. Components similar to those in the first embodiment will be described with the same reference numerals.
As shown in FIGS. 5 and 6, the fraud detection label 11 of the second embodiment includes a label base 2, and the printing layer 4 is partially formed on one side (front side) of the label base 2. Furthermore, the optical change layer 1 is laminated on the entire surface. On the other surface (the pasting side) of the label base material 2, a solvent color detection adhesive layer 9 is provided. Further, a notch 8 cut out in the thickness direction of the layer is provided so that the cross sections of the solvent color detecting adhesive layer 9 and the optical change layer 1 are exposed to the atmosphere.
The material configuration of the optical change layer is the same as in the first embodiment.

(Solvent color detection adhesive layer)
The solvent color detection adhesive layer 9 is a layer formed by combining the solvent color detection layer 3 and the adhesive layer 5 described above, and has a function of coloring when immersed in the solvent A and a label adhesive function. .
More specifically, a material having a label adhesion function is used as a binder constituting the solvent color detection layer 3. By using the solvent color detection adhesive layer 9, it is possible to make a label that can easily detect unauthorized re-peeling by the solvent. Usually, in the case of illegal re-peeling with a solvent, the adhesive layer of the label is the target of dissolution and swelling destruction. Therefore, the method of giving the solvent color detection function to the adhesive layer of the label as in this embodiment is a very effective means against unauthorized re-peeling by the solvent.

  The solvent color detection adhesive layer 9 is preferably applied with an ink composed of a pigment using a material selected so as to dissolve in the solvent A and a binder made of a resin material having a label adhesive function. Can be obtained. In the solvent color detecting adhesive layer 9 in FIG. 6, the round particles dispersed in the layer are shown as pigments 12 having a function of coloring, and other portions are shown as binders having an adhesive function.

  When the solvent A is immersed in the solvent color detection adhesive layer 9, the binder is dissolved in the solvent A and the pigment 12 dispersed in the binder is also dissolved in the solvent A, along the cross section of the label 11 and the cut 8. The color of the pigment 12 propagates and colors the base material 2 and the optical change layer 1 (FIG. 7). The color development is effectively spread by the cuts 8 and facilitates confirmation by the observer.

(Incision)
In this embodiment, the notch 8 is provided in order to make it easy to visually confirm the color development by the solvent A and the change in the visible light transmittance by the solvent B.
The shape of the notch 8 may be a straight line or a curve, and can be changed as needed. However, it is preferable to provide at least the solvent color detection adhesive layer 9 and the optical change layer 1 in the thickness direction so as to expose the cross section. . By providing in this way, it is possible to quickly and effectively cause color development by the solvent A and change in visible light transmittance by the solvent B. As shown in FIG. 7 and FIG. 8, in the label 11 provided with the notches 8, the solvent coloring region 6 and the visible light transmittance changing region 7 are particularly prominent around the notches 8, and can be easily confirmed by the observer. To do.

"Other"
Although the label according to the embodiment of the present invention has been described in detail above, other processes and configurations are possible. For example, in order to improve the adhesion between the respective layers, corona treatment, plasma treatment and / or primer coating may be performed. Furthermore, in order to improve the designability, it is possible to color each layer or to provide an optical reflection layer. Moreover, the structure etc. which incorporated the inlet with an IC chip are also possible.
Moreover, it becomes an article | item with a label by affixing the above-mentioned label to an article | item.

Hereinafter, the present invention will be described in detail with specific examples. In the following examples, “part” means mass part, and “ratio” means mass ratio.
Example 1
Based on the above embodiment, the label 11 shown in FIGS. 5 and 6 was produced.
A resin-impregnated paper having a basis weight of 75 g / m ² was used as the label substrate 2, and an ink composed of the following composition was partially provided on one side thereof by a screen printing method to form a printing layer 4.

<Print layer ink>
(Yellow ink for graphics)
High molecular methacrylic (PMMA) resin 2 parts Low viscosity nitrocellulose 12 parts Yellow pigment 3 parts Cyclohexanone 10 parts.

(Black ink for characters)
High molecular methacrylic (PMMA) resin 2 parts Low viscosity nitrocellulose 12 parts Carbon black 3 parts Cyclohexanone 10 parts.
Next, an ink made of the following composition as the optical change layer 1 was formed on the entire surface of the substrate 2 on the side on which the printed layer 4 was formed so as to have a thickness of 3 μm by the gravure printing method.

<Optical change layer ink>
Acrylic resin C
(Ethanol (SP value 12.7) soluble average molecular weight 13,000) 6 parts Alcohol soluble nitrocellulose (ethanol (SP value 12.7) soluble average molecular weight 70,000) 4 parts Ethanol / IPA / mixed solvent 40 parts.

  Further, as the solvent color detection adhesive layer 9, an ink composed of the following composition is formed on a release treatment surface of a release material [SP-8K, 90 μm thickness by Lintec Co., Ltd.] on which one side is release treatment. After forming uniformly by using a hot melt knife coater so as to be 50 μm, it was bonded to the other surface of the substrate 2 and bonded to obtain a laminate.

<Solvent color detection adhesive layer ink>
Acrylic adhesive (isoparaffin (SP value 7.3) soluble) 100 parts Anthraquinone dye (isoparaffin (SP value 7.3) soluble particle shape) 2 parts Next, a punching blade is fixed to the periphery of the laminate. The intrusion detection label 11 as shown in FIG. 5 was obtained by punching the cut 8 at the same time with the magnet roll.

(Comparative Example 1)
A label was produced in the same manner as in Example 1 except that the optical change layer 1 was not provided.
(Comparative Example 2)
A label was produced in the same manner as in Example 1 except that the layer was formed using an ink composed of the following composition instead of the solvent color detecting adhesive layer 9.

<Adhesive layer ink>
Acrylic adhesive (isoparaffin (SP value 7.3) soluble) 100 parts.
(Comparative Example 3)
A label was produced in the same manner as in Example 1 except that the layer was formed using an ink comprising the following composition instead of the optical change layer 1.

<Ink>
Acrylic resin (ethanol (SP value 12.7) insoluble average molecular weight 13,000) 6 parts Nitrocellulose (ethanol (SP value 12.7) insoluble average molecular weight 70,000) 4 parts MEK / toluene mixed solvent 100 parts.
(Comparative Example 4)
A label was produced in the same manner as in Example 1 except that the layer was formed using an ink comprising the following composition instead of the optical change layer 1.

<Ink>
Acrylic resin E
(Ethanol (SP value 12.7) soluble average molecular weight 650,000) 8 parts Nitrocellulose (ethanol (SP value 12.7) soluble average molecular weight 70,000) 2 parts Ethanol / IPA / mixed solvent 100 parts.

[Evaluation of fraud detection]
The release material was removed from each of the labels of Examples and Comparative Examples, and the release material was stuck on an article to be pasted (high quality paper having a thickness of about 200 μm) to give an article with a label. In all labels except Comparative Example 1 in which the optical change layer 1 was not provided, the optical change layer 1 was in a transparent state.

After immersing these labeled articles in isoparaffin (SP value 7.3), which is a solvent having an SP value of 11 or less, or ethanol (SP value 12.7), which is a solvent having an SP value of 11 or more, the label is attached to the article. I re-exfoliated illegally. With isoparaffin, the adhesive layer portion was dissolved in all labels, and the labels were peeled off from the articles to be applied. Further, in ethanol, the adhesive layer portion swelled in all the labels and the adhesive force was lowered, and the labels were peeled off from the articles to be adhered.
Each re-peeled label was exposed to the atmosphere to evaporate the solvent, and the state of the label was observed. The results are shown in Table 1.

  When immersed in isoparaffin (SP value 7.3), the label of Comparative Example 2 did not change, but the other labels were observed to be colored by anthraquinone dyes mainly in the vicinity of the cut portion and the label edge. . Further, the label of Comparative Example 3 had a mottled pattern formed on the optical change layer on the label surface simultaneously with the coloring, and the pattern and characters on the printed layer were partially hidden, making it difficult to observe.

Moreover, when immersed in ethanol (SP value 12.7), the labels of Example 1 and Comparative Example 2 had mottled patterns formed on the surface, and some of the patterns and characters on the printed layer were hidden, making observation difficult. .
On the other hand, no change was seen in the labels of Comparative Example 1 and Comparative Example 3. Although it was confirmed that the label of Comparative Example 4 was slightly clouded on the entire surface, it was difficult to confirm the cloudiness immediately at first glance.

From the above results, it can be seen that it was in Example 1 that fraud detection was easily confirmed in both cases of isoparaffin (SP value 7.3) and ethanol (SP value 12.7).
In the above examples, isoparaffin and ethanol were used as the solvent, but other organic solvents (SP value 11 or less as a solvent: acetone (SP value 10), methyl ethyl ketone (SP value 9.3), ethyl acetate (9.1). ), Perchlorethylene (9.3) The same results were obtained with isopropanol (11.5) and methanol (14.5) as solvents having an SP value of 11 or more.

  In addition to the resin blending ratios of the examples described above, the optical change layer 1 was produced with the resin material composition shown in Table 2 below, and the fraud detection was evaluated. In the table, “◯” indicates that the compounding ratio is compatible, and “x” indicates that the compounding ratio is incompatible. “Mn” indicates a number average molecular weight (unit: g / mol). Furthermore, the material structure of the optical change layer in the said Example 1 and the comparative example 4 is shown in the table | surface.

  Regarding the combination of the resins of the optical change layer obtained as a result of the present invention (which became “transparent” before immersion in solvent B having an SP value of 11 or more and became “mottled pattern” after immersion in solvent), as described above. The number average molecular weight of the second resin is not less than 5 times the number average molecular weight of the first resin, and the content value of the first resin in the total mass of the first resin and the second resin is this value. Is increased from the first boundary content value C1 (%) to (C1-10) (%), which changes from compatible to non-compatible when the value is increased. When it is within the range from the second boundary content value C2 (%) to (C2 + 10) (%), which changes from incompatible to compatible, a change from transparent to mottled pattern may occur. It was possible.

  For example, in the combination of alcohol-soluble nitrocellulose and acrylic C in Table 2, the number-average molecular weight of alcohol-soluble nitrocellulose is 50,000 times the number-average molecular weight of acrylic C is 13,000, The first boundary content value C1 (%) that changes from compatible to incompatible when the value of the alcohol-soluble nitrocellulose content value occupying the total mass is within the range of 30 to 50%. It is in. Therefore, if the ratio is within the range of the first boundary content C1 (%) to (C1-10) (%), it is possible to cause a change from transparent to a mottled pattern.

  As described above, according to the present invention, it is possible to detect peeling due to a solvent, and therefore, a label that can prevent tampering and reuse can be provided. By attaching this label to a necessary article, it is possible to prevent the counterfeiting or falsification of securities, branded products, certificates, personal authentication media, etc., and to give a function of proving authenticity.

DESCRIPTION OF SYMBOLS 1 ... Optical change layer, 2 ... Label base material, 3 ... Solvent color development detection layer, 4 ... Printing layer, 5 ... Adhesion layer 6 ... Solvent color development area | region, 7 ... Area | region of 2nd optical state, 8 ... Incision, 9 ... Solvent coloring detection adhesive layer, 12... Pigment 10, 11.

Claims (8)

A solvent color detection layer made of a material that changes its color when dissolved in a first solvent having a solubility parameter (SP value) of 11 [(cal / cm ³ ) ^1/2 ] or less, and a solubility parameter (SP value) of 11 And [(cal / cm ³ ) ^1/2 ] or more optical change layer made of a material that dissolves in the second solvent,
The optical change layer includes a first resin having a first number average molecular weight and a second resin having a second number average molecular weight, which are dissolved in the second solvent, and have a first visible light transmittance. In a first optical state indicating
The first number average molecular weight is not less than 5 times the second number average molecular weight;
When the first resin and the second resin are in contact with the second solvent, the optical change layer has a lower transmittance than the first visible light transmittance at a portion where the second solvent is in contact. 2 of Ri Do to a second optical state of the visible light transmittance,
In the optical change layer, the content value of the first resin in the total mass of the first resin and the second resin increases the content value of the first resin on a mass basis. In the range from the first boundary content value C1 (%) to (C1-10) (%) in which the first resin and the second resin change from the compatible state to the incompatible state. or in, or the first and second resin a range near Rukoto from the second boundary content value C2 (%) which changes to the non-phase melt-et compatibilization to (C2 + 10) (%) Feature fraud detection label.   The optical change layer is configured in a state in which the first resin and the second resin are compatible with each other before contacting the second solvent, and exhibits a first visible light transmittance. When the first resin and the second resin are in contact with the second solvent, the first resin and the second resin are in contact with the second solvent. The fraud detection label according to claim 1, wherein and are incompatible with each other.   The fraud detection label according to claim 1 or 2, wherein the second visible light transmittance is a visible light transmittance which is reduced by 5% or more from the first visible light transmittance.   The fraud detection label according to any one of claims 1 to 3, wherein the solvent color detection layer contains an anthraquinone dye or pigment. Fraud detection label according to any one of claims 1 to 4, wherein the solvent color developing sensing layer and having an adhesive function labels. The fraud detection label according to any one of claims 1 to 5 , wherein a cut in the thickness direction of the layer is provided in at least one of the solvent color detection layer or the optical change layer. Said first optical state is a transparent state to visible light, said second optical state, we claim 1, characterized in that to visible light, an opaque state 6 The fraud detection label according to any one of the above. A labeled article, wherein the fraud detection label according to any one of claims 1 to 7 is attached via an adhesive layer.

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