JP2012150271A - Hologram label - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hologram label with a novel forgery-preventive technique in order to prevent damage caused by forgery of a hologram.SOLUTION: In a hologram label 1, on one surface of a base material 2, at least a hologram form layer 3, a light reflective layer 4, and an adhesive layer 5 are laminated, and the adhesive layer 5 contains a material emitting light by stress. Also, in the hologram label 1, on one surface of the base material 2, at least the hologram form layer 3, the light reflective layer 4, and the adhesive layer 5 are laminated, and a layer 6 that contains a material emitting light by stress is provided between the light reflective layer 4 and the adhesive layer 5. Also, the adhesive layer 5 and a release sheet 7 are laminated so as to face each other.

Description

  The present invention relates to a hologram label, and more particularly to a hologram label that prevents forgery of a hologram.

  In recent years, there have been frequent incidents of manufacturing counterfeit products using color copiers and the like. For this reason, as a countermeasure against counterfeiting, holograms that require a high level of reproduction technology are attached or transferred to a gift certificate, a credit card, a high-end brand product, or the like as a label. Holograms are used as copy restraining means in that when a hologram is copied by forming a metal reflective layer on the uneven surface, the hologram forming portion is reproduced in black.

  However, with the advancement of technology, a hologram approximated or a counterfeit of the hologram itself has appeared. In order to check such a counterfeit product, for example, Patent Document 1 discloses a technique for incorporating hidden information that is difficult to discriminate into a light diffraction structure of a hologram and using it as a means for discriminating authenticity. As suggested.

However, even with products using these technologies, damage caused by forgery of holograms has become a social problem in recent years due to the advancement of forgery technology.
On the other hand, as a countermeasure against counterfeiting of a hologram label, a holographic label having brittleness is disclosed in Patent Document 2 after it is once attached to an adherend and then peeled off and reattached. It is shown.

  Even in the hologram label as described above, if the hologram itself is skillfully forged, it cannot be visually judged as a forged product, and therefore development of a more advanced anti-counterfeiting technology is urgently required.

JP 2003-344633 A Japanese Patent Laid-Open No. 10-2222071

  SUMMARY OF THE INVENTION An object of the present invention is to provide a hologram label having an anti-counterfeit technology that has not been used in the past in order to prevent damage caused by forgery of a hologram.

  The above object is achieved by the present invention described below. That is, the present invention is a hologram label in which at least a hologram forming layer, a light reflective layer, and an adhesive layer are laminated on one surface of a substrate, and the adhesive layer contains a material that emits light by stress. The hologram label is characterized by being configured.

  As a result, when the hologram label is peeled off from the state of being attached to the adherend, stress is applied to the adhesive layer, and the adhesive layer emits light. The check effect is large.

  In addition, the present invention is a hologram label in which at least a hologram forming layer, a light reflective layer, and an adhesive layer are laminated on one surface of a substrate, and between the light reflective layer and the adhesive layer, The hologram label is characterized in that a layer containing a material that emits light by stress is provided. As a result, when the hologram label is peeled off from the state of being attached to the adherend, the stress is transmitted from the adhesive layer to the stressed light emitting material-containing layer, and the stressed light emitting material-containing layer Emits light, which has a great effect of preventing counterfeiting, which is not possible in the past.

  In the state where stress such as pressure is not applied to the above hologram label, only the hologram (formation layer) can be visually confirmed, and the information of the layer containing the light emitting material with stress cannot be read, so the anti-counterfeiting property is extremely high. It is expensive.

  The hologram label has a structure in which the adhesive layer and the release sheet are bonded so as to face each other, and the release sheet can be peeled from the adhesive layer. Thus, the hologram label can be easily attached to an arbitrary object by the adhesive layer simply by peeling off the release sheet from the hologram label. In addition, the hologram label is easy to handle and is preferable before being attached, without blocking.

  By adopting the above configuration, the hologram label of the present invention has an anti-counterfeit technology that has not existed in the past, and can prevent damage due to forgery of the hologram.

It is sectional drawing which shows one embodiment which is a hologram label of this invention. It is sectional drawing which shows other embodiment which is a hologram label of this invention. It is sectional drawing which shows other embodiment which is a hologram label of this invention.

Next, embodiments of the present invention will be described in detail.
FIG. 1 shows one embodiment which is a hologram label 1 of the present invention. The hologram label 1 has a configuration in which a hologram forming layer 3, a light reflective layer 4, and an adhesive layer 5 are laminated on one surface of a substrate 2, and the adhesive layer 5 contains a material that emits light by stress. .

  FIG. 2 is a cross-sectional view showing another embodiment of the hologram label 1 of the present invention, in which a hologram forming layer 3, a light reflective layer 4, and an adhesive layer 5 are laminated on one surface of a substrate 2. The hologram label 1 has a configuration in which a layer 6 containing a material that emits light by stress is provided between the light reflective layer 4 and the adhesive layer 5.

  FIG. 3 is a cross-sectional view showing another embodiment of the hologram label 1 of the present invention. On one surface of the substrate 2, a hologram forming layer 3, a light reflective layer 4, an adhesive layer 5, and a release layer are shown. A structure in which a sheet 7 is laminated and a material that emits light by stress is contained in the adhesive layer 5, and the adhesive layer 5 of the hologram label in FIG. 1 is bonded to the release sheet 7 so as to face each other. It is. The release sheet 7 can be peeled off from the hologram label 1, and the hologram label can be easily attached to an arbitrary object by the adhesive layer 5.

  Although not shown in FIGS. 1 to 3, for example, a brittle layer is provided between the light reflective layer 4 and the adhesive layer 5, or between the substrate 2 and the hologram forming layer 3. If the hologram label on the adherend is to be peeled off from the adherend, the brittle layer is destroyed and forgery due to the replacement of the hologram label can also be prevented.

Below, the element which comprises the hologram label of this invention is demonstrated in detail.
(Base material)
As the base material 2 of the hologram label, various materials can be applied depending on the use so that the hologram (formation layer) can be observed. For example, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polyamide resins such as nylon 6, polyolefin resins such as polypropylene, cyclic polyolefin resins, vinyl resins such as polyvinyl chloride, acrylics such as polymethyl methacrylate Examples thereof include styrene-based resins such as cellulose resins, imide resins, polycarbonates, and ABS resins, and cellulose films such as cellulose triacetate. The substrate may be a copolymer resin containing these resins as a main component, a mixture (including an alloy), or a laminate composed of a plurality of layers. The substrate may be a stretched film or an unstretched film, but a film stretched in a uniaxial direction or a biaxial direction is preferable for the purpose of improving the strength. The thickness of the substrate is usually about 2.5 to 100 μm, but 4 to 50 μm is preferable.

  The substrate is used as a film, sheet or board formed of at least one layer of these resins. Usually, polyester-based films such as polyethylene terephthalate and polyethylene naphthalate have good balance in terms of strength, heat resistance and price, and are preferably used. Polyethylene terephthalate is particularly optimal.

  Prior to application on the substrate, the substrate is subjected to corona discharge treatment, plasma treatment, ozone treatment, flame treatment, primer (also called an anchor coat, adhesion promoter, or easy adhesive) coating treatment, pretreatment, Easy adhesion treatment such as heat treatment, dust removal treatment, vapor deposition treatment, and alkali treatment may be performed. Moreover, you may add additives, such as a filler, a plasticizer, a coloring agent, and an antistatic agent, to this resin film as needed.

(Hologram forming layer)
The hologram forming layer 3 is formed by forming irregularities of a light diffraction structure such as a hologram on a layer made of a synthetic resin. As holograms, which are representative examples of optical diffraction structures, both planar holograms and volume holograms can be used. Specific examples include relief holograms, Lippmann holograms, Furnell holograms, Fraunhofer holograms, lensless Fourier transform holograms, laser reproduction holograms (images) Hologram), white light reproduction hologram (rainbow hologram, etc.), color hologram, computer hologram, hologram display, multiplex hologram, holographic stereogram, holographic diffraction grating, and the like.

  Synthetic resins constituting the hologram forming layer include polyvinyl chloride, acrylic resins (eg, PMMA), thermoplastic resins such as polystyrene and polycarbonate, unsaturated polyester, melamine, epoxy, polyester (meth) acrylate, urethane (meth). Thermosetting resins such as acrylates, epoxy (meth) acrylates, polyether (meth) acrylates, polyol (meth) acrylates, melamine (meth) acrylates, triazine acrylates, or the above thermoplastic resins and thermosetting resins. In addition, a thermoformable substance having a radically polymerizable unsaturated group, or a radically polymerizable unsaturated monomer added to these to make ionizing radiation curable, etc. Can be used. In addition, photosensitive materials such as silver salt, dichromated gelatin, thermoplastic, diazo photosensitive material, photoresist, ferroelectric, photochromic material, thermochromic material, chalcogen glass, and the like can also be used.

  Formation of a light diffraction structure such as a hologram on the synthetic resin layer can be formed by a conventionally known method using the above materials. For example, when recording a diffraction grating or hologram interference fringes as a relief with surface irregularities, an original plate on which diffraction gratings or interference fringes are recorded in an irregular shape is used as a press mold, and the original plate is overlaid on the resin layer. Then, the concavo-convex pattern of the original plate can be duplicated by heating and pressure-bonding them by appropriate means such as a heating roll. In the case of using a photopolymer, the photopolymer can be coated on the substrate in the same manner, and then the original can be overlaid and duplicated by irradiating a laser beam.

  As described above, the method of recording the diffraction grating or the interference fringes of the hologram on the surface of the hologram forming layer as the relief of the surface irregularities is particularly preferable in terms of mass productivity and low cost. The film thickness of such a hologram layer is preferably in the range of 0.5 to 6 μm, and more preferably in the range of 1 to 4 μm. When a diffraction grating or a hologram interference fringe is recorded on the surface of the hologram forming layer as an uneven relief as described above, the light reflective layer 4 is formed on the relief surface in order to increase the diffraction efficiency.

(Light reflective layer)
As the material constituting the light reflective layer 4, Mg, Al, Ti, Cr, Fe, Co, Ni, Cu, Zn, Ga, Ge, Se, Rb, Pd, Ag, Cd, In, Sn, Sb, A metal such as Te, Au, Pb, or Bi, or an oxide thereof, or a nitride thereof is used alone or in combination to form a thin film. Of these, Al, Cr, Ni, Ag, or Au is particularly preferable. In order to form the light reflective layer with these thin films, thin film forming methods such as vacuum deposition, sputtering, and ion plating are used.

  Although the thickness of a light reflective layer can be suitably set from viewpoints of the color tone, design, use, etc. of a light reflective layer, 50 to 1 micrometer is preferable and 100 to 1000 micrometers is more preferable. Further, when it is desired to provide transparency to the light reflective layer, it is preferably 200 mm or less, and when it is desired to provide concealability to the light reflective layer, the thickness is preferably more than 200 mm.

(Layer containing material that emits light by stress)
The layer 6 containing a material that emits light due to the stress of the present invention, that is, the stress-luminescent material-containing layer is provided between the light-reflective layer 4 and the adhesive layer 5, and includes a binder (bonding agent) and a stress-luminescent material. It can be formed by printing ink composed of additives, solvents and the like. A material that emits light by stress, that is, a stress-stimulated luminescent material, has a property that the material itself emits light by strain energy applied from the outside, and has a property of changing emission intensity in proportion to the strain energy. The stress luminescent material is, for example, a material (ceramics) in which an element serving as a luminescent center is added to an inorganic crystal skeleton whose structure is highly controlled, and is obtained in the form of powder particles. Materials that emit light at various wavelengths from ultraviolet to visible to infrared have been obtained by selecting the kind of inorganic material or emission center. The printed part containing such a stress-stimulated luminescent material can be read visually or by a machine.

  Since the hologram label of the present invention contains a material that emits light by stress in the adhesive layer described later, or the stress-luminescent material-containing layer between the light reflective layer and the adhesive layer, the hologram label is attached. Attempting to peel off the hologram label from the state where it is attached to the body is stressed and emits light to at least one of the adhesive layer and the stress-stimulated luminescent material-containing layer, and there is a check effect against counterfeiting that has not existed in the past. It will be big.

The stress-stimulated luminescent material can be divided into a stress-stimulated luminescent material and a stress-stimulated phosphorescent material according to the decay time of luminescence due to given energy. Examples of fluorescent materials include strontium aluminate with europium added as the emission center (SrAl ₂ O ₄ : Eu, green emission), zinc sulfide with manganese emission center (ZnS: Mn, emission in yellow green) ) And the like. These stress luminescent materials are present as particles in the printing ink, and the ink is printed to form a layer containing the stress luminescent material. In particular, it is possible to adjust the printing ink using a material in which a stress light emitting material is dispersed in a highly transparent polymer resin in the form of a so-called nanoparticle having a particle diameter of about 10 to 200 nm. This is preferably carried out because it can be improved and stabilized. Examples of the polymer resin in which the above-described stress-luminescent material of nanoparticles is dispersed include polymethyl methacrylate (PMMA) and epoxy resin.

  The ink used to form the layer containing the stress-stimulated luminescent material has a binder (bonding agent), a stress-stimulated luminescent material, and an additive so that the ink characteristics according to the printing method can be obtained and the required luminescence intensity can be obtained. The blending ratio of the agent, solvent, etc. is determined. For printing for forming a layer containing a stress-stimulated luminescent material, generally known methods such as intaglio, letterpress, offset, screen, gravure, flexographic printing, ink jet printing, spray printing or coating can be employed.

(Adhesive layer)
The adhesive layer 5 can be composed of an adhesive having adhesiveness at room temperature or a heat-sensitive adhesive, and can contain a material that emits light by stress in the adhesive layer. In the case of an adhesive, for example, vinyl acetate resin, acrylic resin, vinyl acetate-acrylic copolymer, vinyl acetate-vinyl chloride copolymer, ethylene-vinyl acetate copolymer, polyurethane resin, natural rubber, chloroprene rubber, nitrile For example, rubber. In the case of a heat-sensitive adhesive, it is more preferably formed from a thermoplastic resin having a glass transition temperature of 50 ° C. to 80 ° C., for example, polyester resin, vinyl chloride-vinyl acetate copolymer resin, acrylic resin, butyral resin, epoxy It is preferable to select a resin having an appropriate glass transition temperature from a resin having good adhesiveness when heated, such as a resin, a polyamide resin, and a vinyl chloride resin.

  The stress-stimulated luminescent material contained in the adhesive layer can be the same as the stress-stimulated luminescent material described above for the stress-stimulated luminescent material-containing layer, so that the required luminescence intensity can be obtained and depending on the printing method The blending ratio of the stress-stimulated luminescent material, the additive, the solvent, etc. to the above-mentioned pressure-sensitive adhesive or heat-sensitive adhesive is determined so as to have the ink characteristics.

In the present invention, the adhesive layer can be composed of the above-mentioned pressure-sensitive adhesive or heat-sensitive adhesive. However, if the adhesive layer is provided with a pressure-sensitive adhesive, it is possible to simply press the hologram label on the adherend by hand, and to apply an iron or heater The hologram label can be easily attached to the adherend without using a heating means such as the above, which is preferable. When the adhesive layer is composed of a pressure-sensitive adhesive, it is usually easy to handle without being blocked by the hologram label before being attached by being attached to a later-described release sheet. The coating amount of the adhesive layer is generally about 8 to 30 g / m ² (solid content), and is formed by a conventionally known method, that is, a gravure coat, a gravure reverse coat, a roll coat or the like. Can do.

(Peeling sheet)
The release sheet 7 used in the present invention may be a conventionally known plastic film, for example, a polyethylene terephthalate film, a polyethylene terephthalate film having a microvoid inside the substrate, and the like. Further, a polylaminate paper in which polyethylene or the like is laminated on glassine paper or pigment-coated paper, or a synthetic paper mainly composed of polypropylene or the like can be used as the release sheet. However, the resin film, as a release layer on the surface of the synthetic paper, a silicone release agent or a wax-based release agent 0.03g / m ² ~0.20g / m ² coating to form, an adhesive layer Can be improved.

Example 1
A polyethylene terephthalate resin film having a thickness of 50 μm is prepared as the transparent substrate 2, and an ultraviolet curable resin is applied to one side of the film, and cured by irradiating ultraviolet rays in a state where a relief hologram replication mold is pressure-bonded. A hologram forming layer 3 having fine irregularities was formed. Aluminum is vapor-deposited on the fine irregularities of the obtained hologram forming layer 3 to a thickness of 400 mm to form a light reflective layer 4, and an ethylene-vinyl acetate copolymer is formed on the surface of the light reflective layer. Strontium aluminate (SrAl ₂ O ₄ : Eu, light emitting in green) added with europium as the light emission center as a stress light-emitting material, polymethyl methacrylate (PMMA) An ink (including a solvent) added at a rate of 30% by mass with a material dispersed in a polymer resin is applied at 20 g / m ² (solid content) to form an adhesive layer 5, and further onto glassine paper. A release sheet 7 of polylaminate paper laminated with polyethylene was laminated to produce a hologram label of Example 1.

(Example 2)
As in Example 1, a polyethylene terephthalate resin film having a thickness of 50 μm was prepared as the transparent substrate 2, and an ultraviolet curable resin was applied to one side thereof, and ultraviolet rays were irradiated in a state where a relief hologram replication mold was pressure-bonded. And cured to form a hologram forming layer 3 having fine irregularities of the hologram. Aluminum was vapor-deposited on the fine irregularities of the obtained hologram forming layer 3 to a thickness of 400 mm to form a light reflective layer 4. Next, on the light-reflective layer, a layer (stress luminescent material-containing layer) 6 containing a material that emits light by stress is formed by gravure printing using an ink containing the following stress luminescent material, Furthermore, an adhesive made of an ethylene-vinyl acetate copolymer is applied at 20 g / m ² (solid content) on the stress-stimulated luminescent material-containing layer to form an adhesive layer 5, and polyethylene is further applied to glassine paper. The release sheet 7 of the laminated polyrami base paper was laminated to produce the hologram label of Example 2.

As an ink containing a stress-stimulated luminescent material, nanoparticles of strontium aluminate (SrAl ₂ O ₄ : Eu, luminescent in green) added with europium as the luminescent center were used. Polymethylmethacrylate (PMMA) The gravure ink was prepared by adding the material dispersed in the molecular resin and other vehicles and additives.

  In the hologram labels of Examples 1 and 2 obtained above, the hologram (formation layer) can be visually confirmed, and further contains an adhesive layer or a stress-stimulated luminescent material between the light reflective layer and the adhesive layer. Since the layer contains a material that emits light due to stress, stress is applied to the adhesive layer or the stress-stimulated luminescent material-containing layer when the hologram label is peeled off from the state where the hologram label is attached to the adherend. , It emits light and has a great effect of preventing counterfeiting, which has never been seen before. In other words, if the attached hologram label is not peeled off, only the hologram (formation layer) can be visually confirmed in a state where stress such as pressure is not applied to the hologram label, and information on the layer containing the material that emits light by the stress Since it cannot be read, the anti-counterfeiting property is very high.

  However, the light emission by the stress luminescent material after peeling off the hologram labels of Examples 1 and 2 is such that the hologram label of Example 1 in which the adhesive layer itself located on the peeled surface emits light emits light more strongly. And the check effect against forgery was great.

DESCRIPTION OF SYMBOLS 1 Hologram label 2 Base material 3 Hologram formation layer 4 Light reflection layer 5 Adhesive layer 6 Layer containing the material light-emitted by stress 7 Release sheet

Claims (3)

  A hologram label in which at least a hologram forming layer, a light-reflective layer, and an adhesive layer are laminated on one surface of a base material, wherein the adhesive layer contains a material that emits light by stress. Hologram label.   A hologram label in which at least a hologram forming layer, a light reflective layer, and an adhesive layer are laminated on one surface of a substrate, and a material that emits light by stress between the light reflective layer and the adhesive layer. A hologram label provided with a layer containing the same. The hologram label according to claim 1 or 2, wherein the adhesive layer and the release sheet are bonded so as to face each other, and the release sheet is peelable from the adhesive layer. .

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