Laminate for forgery prevention, accessory of laminate for forgery prevention, and method for producing same

Abstract

To provide a laminate for forgery prevention having enhanced determination accuracy of authenticity determination, an accessory of the laminate for forgery prevention using the same, a method for producing the same, and the like.SOLUTION: A laminate for forgery prevention comprises a laminate having a transparent substrate and a thin line pattern formed on one surface of the transparent substrate, where an image clarity (DOI) measured by irradiating the thin line pattern with light from the other surface side of the transparent substrate by a method in accordance with ASTM D5767-95 (2012) is 70 or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a counterfeit prevention laminate, an accessory to the counterfeit prevention laminate, and a method for producing the same. [Background technology]

[0002] As a measure to prevent the distribution of counterfeit goods, a system is known in which a two-dimensional code or an RF (Radio Frequency Identification) tag is attached to a product to determine whether the product is genuine. For example, Patent Document 1 discloses an authenticity determination device that reads identification information of an object with a mobile terminal, and uses that information to determine whether the object is genuine and also to confirm distribution information of the object. Furthermore, for example, Patent Document 2 discloses a determination device that determines the authenticity of a hologram image formed by a diffraction pattern. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2020-123108 [Patent Document 2] Japanese Patent Application Laid-Open No. 2001-307172 Summary of the Invention [Problem to be solved by the invention]

[0004] However, two-dimensional codes and hologram images can be easily copied, and information on RF tags can also be easily read and rewritten, making it possible to impersonate or copy products. As such, conventional measures to prevent the distribution of counterfeit goods still have security problems.

[0005] Therefore, the present inventors have developed a new method for determining authenticity, in which a counterfeit-preventive laminate having a fine line pattern is irradiated with light and the authenticity is determined based on the reflected light. This method has the advantage that it is difficult to counterfeit and also has the advantage that it is unlikely to impair the design of the product to which it is attached. However, depending on the manner in which the counterfeit-preventive laminate is used, reading errors may require multiple readings, leaving room for improvement in the accuracy of authenticity determination.

[0006] The present invention has been made in view of the above-mentioned problems, and aims to provide an anti-counterfeiting laminate having a fine line pattern that is difficult to counterfeit and that improves the accuracy of authenticity determination, as well as an accessory to the anti-counterfeiting laminate that uses the same and a method for manufacturing the same. [Means for solving the problem]

[0007] As a result of extensive research to solve the above problems, the present inventors have newly discovered that high image clarity (DOI value) of a counterfeit-preventive laminate having a fine line pattern can improve the accuracy of authentication, and have thus completed the present invention. That is, the present invention provides various specific embodiments as shown below.

[0008] [1] A transparent substrate; a thin line pattern formed on one surface of the transparent substrate; The image clarity (DOI value) measured by irradiating the thin line pattern with light from the other surface side of the transparent substrate in accordance with ASTM D5767-95(2012) is 70 or more. Anti-counterfeit laminate.

[0009] [2] The total light transmittance of the transparent substrate is 50% or more. The counterfeit prevention laminate according to [1].

[0010] [3] The thickness of the transparent substrate is 10 to 100 μm. The counterfeit prevention laminate according to [1] or [2].

[0011] [4] the laminate further includes an adhesive layer covering the thin line pattern on one surface of the transparent substrate, The haze of the adhesive layer is more than 50%. The anti-counterfeit laminate according to any one of [1] to [3].

[0012] [5] The laminate further has an adhesive layer covering the thin line pattern on one surface of the transparent substrate, The haze of the adhesive layer is 50% or less. The anti-counterfeit laminate according to any one of [1] to [3].

[0013] [6] An adherend; and the anti-counterfeit laminate according to any one of [1] to [5] attached to the adherend. Anti-counterfeit laminate accessories.

[0014] [7] The image clarity (DOI value) measured by irradiating light from the attached surface of the anti-counterfeit laminate using a method in accordance with ASTM D5767-95 (2012) is 70 or more. [6] An accessory to the anti-counterfeit laminate.

[0015] [8] A preparation step of preparing an adherend and the anti-counterfeit laminate according to any one of [1] to [5]; an attachment step of attaching the anti-counterfeit laminate to the adherend, In the attachment step, an anti-counterfeit laminate accessory is obtained, which has an image clarity (DOI value) of 70 or more as measured by irradiating light from the attachment surface of the anti-counterfeit laminate using a method in accordance with ASTM D5767-95 (2012). Method for manufacturing anti-counterfeit laminate accessories. [Effects of the Invention]

[0016] According to the present invention, it is possible to provide a counterfeit prevention laminate with improved accuracy in determining authenticity, as well as an accessory to the counterfeit prevention laminate using the same and a method for manufacturing the same. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a perspective view showing an example of how the authenticity determining device of the present embodiment is used; [Figure 2] 1 is a perspective view of the anti-counterfeit laminate of the present embodiment as viewed from the transparent substrate side. [Figure 3] 1 is a cross-sectional view of the anti-counterfeit laminate of the present embodiment attached to an adherend. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail with reference to the drawings as necessary. However, the present invention is not limited to this embodiment, and various modifications are possible without departing from the spirit of the present invention. In the drawings, the same elements are denoted by the same reference numerals, and redundant explanations will be omitted. Furthermore, positional relationships such as up, down, left, and right are based on the positional relationships shown in the drawings unless otherwise specified. Furthermore, the dimensional ratios of the drawings are not limited to the ratios shown. Furthermore, in this specification, the expression of a numerical range, for example, "1 to 100," includes both the lower limit "1" and the upper limit "100." The same applies to the expression of other numerical ranges.

[0019] 1. Anti-counterfeit laminate The anti-counterfeit laminate 100 of this embodiment comprises a laminate having a transparent substrate 10 and a fine line pattern 20 formed on one surface 10b of the transparent substrate 10, and has an image clarity (DOI value) of 70 or more, measured by irradiating light onto the fine line pattern 20 from the other surface side of the transparent substrate 10 in accordance with a method in accordance with ASTM D5767-95(2012).

[0020] Before describing the details of the counterfeit prevention laminate 100 of this embodiment, the configuration of the authentication determination method and authenticity determination device of this embodiment will first be described. FIG. 1 shows a perspective view illustrating an example of how the authenticity determination device 200 is used. As shown in FIG. 1, the authenticity determination device 200 includes, for example, an irradiation device 210 that irradiates light onto the fine line pattern 20 of the counterfeit prevention laminate 100, a light receiving device 220 that receives light reflected from the fine line pattern 20, and a determination unit 230 that performs authenticity determination based on the reflected light. In the example shown in FIG. 1, the irradiation device 210 and the light receiving device 220 are located at approximately the same position.

[0021] 1, the authentication method of this embodiment performs authentication based on reflected light. Therefore, in order for the authentication unit 230 to output an authentication result with high accuracy, it is preferable that the reflected light obtained by irradiating a predetermined light is consistent and without variation. However, in reality, depending on the mode of use, unintended scattering or the like occurs in the anti-counterfeit laminate 100, which poses a problem that the reflected light received by the light-receiving device 220 is prone to variation.

[0022] If variations in the reflected light occur, there is a risk that even if the reflected light is received from the thin line pattern attached to an authentic product, the determination unit 230 may mistakenly determine that the product is counterfeit. Furthermore, even if such an erroneous determination occurs, it is difficult for the user to determine whether the determination result is true or whether it is due to an erroneous determination by the device. Furthermore, if variations in the reflected light occur, there is a concern that the verification process may take a long time, such as requiring repeated light irradiation and light reception operations to obtain the desired reflected light. Therefore, there is a demand for an anti-counterfeiting laminate with improved accuracy in authenticity determination.

[0023] Next, the configuration of the anti-counterfeit laminate of this embodiment will be described. Fig. 2 shows a perspective view of the anti-counterfeit laminate. As shown in Fig. 2, the anti-counterfeit laminate 100 of this embodiment comprises a laminate having a transparent substrate 10 and a fine line pattern 20 formed on one surface 10b of the transparent substrate 10. The anti-counterfeit laminate 100 of this embodiment may further include an adhesive layer 30 that covers the fine line pattern on one surface 10b of the transparent substrate 10, as necessary.

[0024] Fig. 3 shows a cross-sectional view of the anti-counterfeit laminate of this embodiment when attached to an adherend. As shown in Fig. 3, the anti-counterfeit laminate 100 of this embodiment can be used by being attached to the surface of an adherend 300 via an adhesive layer 30. In this case, the fine line pattern 20 is located between the transparent substrate 10 and the surface of the adherend 300. The transparent substrate 10 located on the outermost surface also functions as a protective layer that covers the fine line pattern 20.

[0025] Light irradiated from the irradiation device 210 of the authenticity determination device 200 enters the anti-counterfeit laminate from the transparent substrate 10 side, passes through the transparent substrate 10 from surface 10a to surface 10b, and reaches the fine line pattern 20 and adhesive layer 30. A portion of the incident light is reflected, and the reflected light is affected by the fine line pattern. For example, if the fine line pattern acts like a diffraction grating, the reflected light may be diffracted light.

[0026] 1.1. Imageability (DOI) As described above, in order to improve the accuracy of authentication determination, in this embodiment, the image clarity (DOI value) measured by irradiating light onto the thin line pattern 20 from the other side of the transparent substrate 10 using a method in accordance with ASTM D5767-95 (2012) is set to 70 or more. The DOI value specified here refers to the value when the anti-counterfeit laminate 100 is not attached to the adherend 300, specifically, the image clarity (DOI value) of the anti-counterfeit laminate 100 alone before use. If the DOI value is less than 70, depending on how the anti-counterfeit laminate is used, reading errors may occur or multiple readings may be required, which tends to result in poor accuracy in authenticity determination. In this specification, the DOI value refers to a value measured by the method described in the Examples below.

[0027] Here, the DOI value is a DOI scale value defined in ASTM D5767-95 (2012), a standard test method for instrumentally measuring the gloss of image clarity on a coating surface. The DOI scale value ranges from 0 to 100, with a value of 100 representing perfect DOI. In this embodiment, the image clarity (DOI value) measured by irradiating the thin-line pattern 20 with light from the other surface of the transparent substrate 10 is more preferably 73 or higher, even more preferably 75 or higher, and particularly preferably 78 or higher. The higher the image clarity (DOI value), the more likely the accuracy of authenticity determination will improve. The upper limit of the DOI value is not particularly limited, but is preferably 100 or lower and may be less than 100.

[0028] On the other hand, the DOI value may vary depending on the manner in which the anti-counterfeit laminate 100 is used. For example, when the anti-counterfeit laminate 100 is attached to an adherend 300, the measured DOI value may be affected by the transparency and material of the adherend 300, as well as the uneven shape of the attachment surface of the adherend 300. Therefore, when the anti-counterfeit laminate 100 is attached to the adherend 300 (i.e., when it is used as an accessory to the anti-counterfeit laminate, as described below), it is more preferable that the image clarity (DOI value) measured by irradiating light from the attachment surface of the anti-counterfeit laminate 100 using a method in accordance with ASTM D5767-95(2012) is 70 or higher. The image clarity (DOI value) is more preferably 72 or higher, even more preferably 74 or higher, and particularly preferably 75 or higher. The higher the image clarity (DOI value), the more likely it is that the accuracy of authentication determination will improve. In this case, the upper limit of the DOI value is not particularly limited, but is preferably 100 or less, and may be less than 100.

[0029] When the anti-counterfeit laminate 100 is used alone, the DOI value can be adjusted by the composition and thickness of the transparent substrate, the thickness and pattern of the fine lines constituting the fine line pattern, and the composition and surface roughness of the adhesive layer, if any. For example, the DOI value can be adjusted by blending low-refractive or high-refractive fine particles into the transparent substrate or adhesive layer, and adjusting the particle size or content ratio of the fine particles. Furthermore, when the anti-counterfeit laminate 100 is attached to an adherend 300, the DOI value can be adjusted by the composition and thickness of the transparent substrate, the thickness and pattern of the fine lines constituting the fine line pattern, and the composition and surface roughness of the adhesive layer, if any, as well as the transparency and material of the adherend 300, and the uneven shape of the adhesive surface. The DOI value can be measured using the method described in the Examples.

[0030] 1.1.Transparent base material In this embodiment, a transparent substrate is used as the substrate onto which incident light is incident, as shown in Figure 1. Note that "transparent" means that the total light transmittance is 50% or more.

[0031] The material for the transparent substrate is not particularly limited, but examples thereof include transparent inorganic substrates such as glass; and transparent organic substrates such as acrylic acid esters, methacrylic acid esters, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polycarbonate, polyarylate, polyvinyl chloride, polyethylene, polypropylene, polystyrene, nylon, aromatic polyamide, polyether ether ketone, polysulfone, polyethersulfone, polyimide, and polyetherimide.

[0032] Among these, polyethylene terephthalate, polyimide, or polyethylene naphthalate is preferred. The use of polyethylene terephthalate tends to improve the productivity and cost reduction effect for producing the anti-counterfeit laminate, and also tends to further improve the adhesion between the transparent substrate and the thin wire. In addition, the use of polyimide tends to further improve the heat resistance of the anti-counterfeit laminate. Furthermore, the use of polyethylene naphthalate tends to further improve the adhesion between the transparent substrate and the thin wire.

[0033] The transparent substrate may be made of one material or may be a laminate of two or more materials. When the transparent substrate is a multilayer body made of two or more materials, the transparent substrate may be a laminate of organic or inorganic substrates, or a laminate of an organic substrate and an inorganic substrate.

[0034] The total light transmittance of the transparent substrate is preferably 50% or more, 60% or more, 70% or more, 80% or more, or 85% or more. A total light transmittance of 50% or more tends to further improve the reflected light intensity and improve the readability of the reflected light. In addition, the thickness when attached to the adherend is thin, and the design of the adherend is less likely to be impaired. The upper limit of the total light transmittance of the transparent substrate is not particularly limited, but may be 100% or less, or 99% or less. The total light transmittance can be measured in accordance with JIS K 7361-1:1997.

[0035] The thickness of the transparent substrate is preferably 5 to 500 μm, 7.5 to 250 μm, 10 to 100 μm, or 15 to 75 μm. When the thickness of the transparent substrate is 5 μm or more, the rigidity of the anti-counterfeit laminate is further improved, and minute deformation due to external factors such as lamination or expansion and contraction over time, as well as the accompanying scattering of light, are easily suppressed, which tends to further improve reading efficiency. Furthermore, when the thickness of the transparent substrate is 500 μm or less, light absorption and scattering by the transparent substrate are more easily suppressed, which tends to further improve reading efficiency. Furthermore, the thickness when laminated to an adherend is thin, which is less likely to impair the design of the adherend.

[0036] 1.2. Thin line pattern The thin line pattern is any pattern composed of thin lines. The thin line pattern may be formed as a desired pattern, for example, a grid pattern (mesh pattern) of triangles, squares, hexagons, etc., or a line pattern. The thin lines are not limited to straight lines, but may also be curved or wavy lines. The thin line pattern is preferably formed as a periodic pattern of thin lines. In this way, the thin line pattern forms a diffraction grating, and by irradiating light, a diffraction image reflecting the fine structure can be obtained.

[0037] When a predetermined light is irradiated onto such a thin line pattern from an irradiation device, the thin line pattern reflects a predetermined reflected light. Here, the thin line pattern may act like a diffraction grating, and the reflected light may be diffracted light. For example, if the thin line pattern includes multiple thin lines with a line width of 5 μm or less arranged at equal intervals with a periodic pitch of approximately several hundred μm, a diffraction image is observed in the reflected light, and the optical image includes such a diffraction image. In this case, the generated diffraction image may include a diffraction spot image or a diffraction stripe pattern. Furthermore, a predetermined optical image can be formed and acquired by passing the diffracted light through, for example, a Fourier transform lens. In other words, using such an optical image can also prevent counterfeiting of laminates.

[0038] Then, for the purpose of guaranteeing the authenticity of the anti-counterfeit laminate, it is possible to acquire and verify optical image information relating to an optical image or a diffraction image obtained from the fine line pattern attached to the anti-counterfeit laminate. In other words, when light is irradiated onto the anti-counterfeit laminate, an optical image or a diffraction image is obtained due to interference of reflected light from the fine line pattern, and by verifying the optical image or the diffraction image, it is possible to prevent counterfeiting.

[0039] Furthermore, if the fine line pattern is composed of multiple fine lines with a line width of 5 μm or less and arranged at equal intervals with a pitch of several hundred μm, the individual fine lines are invisible to the naked eye, and the fine line pattern is transparent. Therefore, the fine line pattern may be a pattern that is difficult to see. Therefore, even if the anti-counterfeit laminate is attached to an adherend, the design and posted information are not impaired. On the other hand, as described above, even with such a transparent fine line pattern, it is possible to obtain a diffraction image generated by diffracted light that is generated only when a specific light is irradiated.

[0040] The thin wires may be made of a material having a total light transmittance of less than 50%. The thin wires may contain non-metallic materials, but are preferably thin wires containing metals. Examples of metals include, but are not limited to, gold, silver, copper, and aluminum. Among these, silver or copper is preferred, and copper is more preferred. Furthermore, the thin wires do not need to be electrically conductive, and the thin wire pattern does not need to ensure electrical conductivity at any two points on the pattern.

[0041] From the above viewpoints, it is preferable that the thin lines are difficult to see with the naked eye due to their thinness. For example, the line width of the thin lines is preferably 5.0 μm or less, 0.1 to 5.0 μm, or 0.3 to 5.0 μm. A line width of 5.0 μm or less reduces the visibility of the thin lines. This allows a thin line pattern to be applied without compromising the design of the adherend. Furthermore, such thin lines with low visibility are difficult to manufacture, and therefore also contribute to ensuring that they are difficult to replicate. Here, the line width in this embodiment refers to the line width of the thin lines when projected onto the surface of the transparent substrate from the side on which the thin lines are arranged.

[0042] The pitch between the fine lines in a predetermined direction is preferably 1.0 to 1000 μm, 5.0 to 500 μm, 50 to 250 μm, or 100 to 250 μm. When the pitch is 1.0 μm or more, the visibility of the fine lines decreases. This allows the fine line pattern to be applied without impairing the design of the adherend. Furthermore, when the pitch is 1000 μm or less, the influence of the fine line pattern is more easily reflected in the reflected light, which tends to further improve reading efficiency.

[0043] The aperture ratio, which is the ratio of the area of ​​the portion of the fine line pattern having no fine lines formed therein, of a predetermined area is preferably 80 to 99.9 area%, 85 to 99.8 area%, 90 to 99.6 area%, or 95 to 99.5 area%. The aperture ratio OR can also be expressed as transmittance. This prevents the fine line pattern from impairing the design of the adherend or the information displayed. When the fine line pattern has a mesh pattern shape, a fine line pattern with a line width of 1 μm and a pitch of 200 μm can achieve an aperture ratio of 99%.

[0044] The total light transmittance of the entire thin line pattern, including areas where thin lines are not formed, is preferably 75 to 99%, 80 to 98%, or 85 to 98%. The total light transmittance can be measured in accordance with JIS K 7361-1:1997.

[0045] In a preferred aspect of this embodiment, the thin line pattern is formed on a transparent substrate. With this configuration, it is possible to acquire an optical image or a diffraction image while maintaining the visibility of the underlying surface. While the mechanism is unclear, it is believed that this is because the optical image or the diffraction image can be acquired by utilizing Fresnel reflection on the back surface of the transparent substrate. Therefore, even if the adherend has any printing on it, it is possible to acquire only the optical image information derived from the transparent thin line pattern applied thereon.

[0046] 1.3. Adhesive layer The adhesive layer is used to attach the anti-counterfeit laminate to an adherend, and may be formed on one surface of a transparent substrate so as to cover the fine line pattern. The adhesive layer is not particularly limited, but is preferably transparent and capable of exhibiting good adhesion to a conductive sheet or substrate. The adhesive layer may be a single layer or may have multiple layers.

[0047] The adhesive resin constituting such an adhesive layer is not particularly limited, and examples thereof include acrylic resins, urethane resins, polyisobutylene resins, olefin resins, acrylic urethane resins, and polyester resins. Also usable are thermosetting resins such as phenolic resins, thermosetting epoxy resins, thermosetting polyimides, melamine resins, urea resins, unsaturated polyester resins, alkyd resins, polyurethanes, diallyl phthalate resins, and silicone resins; UV-curable resins such as urethane acrylates, acrylic resin acrylates, epoxy acrylates, silicone acrylates, and UV-curable epoxy resins; thermoplastic resins such as polyolefins and polyesters; commercially available coating agents; rubber-based adhesives such as polyisoprene and polyisoprene-butylene; acrylic adhesives; and silicone adhesives.

[0048] The thickness of the adhesive layer is preferably 1.0 to 500 μm, 10 μm to 250 μm, or 25 to 150 μm. When the thickness of the adhesive layer is 5 μm or more, adhesion to the adherend tends to be further improved. Furthermore, when the thickness of the adhesive layer is 500 μm or less, light absorption and scattering by the transparent substrate is more easily suppressed, so reading efficiency tends to be further improved. Furthermore, the thickness when attached to the adherend is thin, so the design of the adherend tends to be less impaired.

[0049] In a preferred embodiment, the haze of the adhesive layer is preferably greater than 50%, more preferably 60 to 100%, and even more preferably 70 to 90%. When the haze of the adhesive layer is extremely high, scattered light from the adherend, which can normally cause noise and impair the accuracy of determination, is dispersed over a wider angular range, so that the intensity of noise light around the optical image or diffraction image is relatively reduced, resulting in a clearer image and improved reading efficiency. In this specification, haze refers to a value measured by the method described in the Examples below.

[0050] In another preferred embodiment, the haze of the adhesive layer is preferably 30% or less, more preferably 0 to 10%, and even more preferably 0 to 3%. The lower the haze of the adhesive layer, the smaller the scattering in the adhesive layer, and the more significantly the reading efficiency tends to improve.

[0051] 2. Manufacturing method of anti-counterfeit laminate The method for manufacturing the anti-counterfeit laminate of this embodiment includes a pattern formation step of forming a fine line pattern on a transparent substrate, and may also include an adhesive layer formation step of forming an adhesive layer on the substrate so as to cover the fine line pattern, as necessary.

[0052] The method for forming the fine line pattern in the pattern formation step is not particularly limited, and for example, the fine line pattern may be formed on the transparent substrate by various printing methods. More specifically, an ink containing metal particles may be printed on the transparent substrate by letterpress printing, gravure printing, bar coating printing, spray coating, spin coating, reverse transfer printing, or the like, and then baked to form the fine line pattern containing metal.

[0053] Furthermore, in the adhesive layer formation process, although not particularly limited, for example, an adhesive layer may be formed by applying a resin composition so as to cover the fine line pattern, or an adhesive layer may be formed by attaching double-sided tape so as to cover the fine line pattern.

[0054] 3. Anti-counterfeit laminate accessories The anti-counterfeit laminate accessory of this embodiment comprises an adherend and the above-mentioned anti-counterfeit laminate attached to the adherend. The adherend may be the product itself or the product packaging.

[0055] It is more preferable that the anti-counterfeit laminate accessory has an image clarity (DOI value) of 70 or more, measured by irradiating light from the attached surface of the anti-counterfeit laminate using a method in accordance with ASTM D5767-95 (2012) while the anti-counterfeit laminate is attached to an adherend. An image clarity (DOI value) of 70 or more tends to further improve the accuracy of authenticity determination, and the image clarity (DOI value) is more preferably 72 or more, even more preferably 74 or more, and particularly preferably 75 or more. In this case, the upper limit of the DOI value is not particularly limited, but is preferably 100 or less, and may be less than 100.

[0056] 4. Manufacturing method of anti-counterfeit laminate accessory The method for producing an anti-counterfeit laminate accessory of this embodiment includes a preparation step of preparing an adherend and an anti-counterfeit laminate, and an attachment step of attaching the anti-counterfeit laminate to the adherend. In this attachment step, it is preferable to obtain an anti-counterfeit laminate accessory having an image clarity (DOI value) of 70 or more, measured by irradiating light from the attachment surface to which the anti-counterfeit laminate is attached, using a method in accordance with ASTM D5767-95 (2012).

[0057] The method of attachment in the attachment step is not particularly limited, but examples include a method in which the anti-counterfeit laminate is attached to the adherend via an adhesive layer of the anti-counterfeit laminate. [Example]

[0058] The features of the present invention will be explained in more detail below with reference to examples, but the present invention is not limited thereto. That is, the materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Furthermore, the values ​​of various production conditions and evaluation results in the following examples represent preferred upper or lower limits in the embodiments of the present invention, and preferred numerical ranges may be defined by combining the above-mentioned upper or lower limits with the values ​​of the following examples or values ​​of the examples themselves.

[0059] Example 1 20 parts by mass of cuprous oxide nanoparticles with a primary particle size of 21 nm, 4 parts by mass of a dispersant (manufactured by BYK-Chemie, product name: Disperbyk-145), 1 part by mass of a surfactant (manufactured by AGC Seimi Chemical Co., Ltd., product name: S-611), and 75 parts by mass of ethanol were mixed to prepare an ink containing 20% ​​by mass of cuprous oxide nanoparticles.

[0060] Cosmoshine (manufactured by Toyobo Co., Ltd., product name: A4160, single-sided easy-adhesion type, thickness: 50 μm, total light transmittance: 89.3%) was used as a transparent substrate, and the ink prepared as described above was printed in the desired fine line pattern on its easy-adhesion surface. Specifically, the ink was first applied to the surface of a blanket, and then the ink-coated blanket surface was brought into contact with a plate having grooves for the fine line pattern, transferring some of the ink on the blanket surface to the raised surfaces of the plate. Thereafter, the blanket surface coated with the remaining ink was brought into contact with the substrate, and the ink in the fine line pattern was transferred onto the substrate. Note that the line width of the fine line pattern was 3 μm and the pitch was 60 μm.

[0061] Plasma was generated from the fine line pattern ink obtained as described above using microwaves generated at an output of 0.9 kW in an atmosphere under reduced pressure with a water molecule partial pressure of 100 Pa, and the plasma was reacted with the ink for 180 seconds to form a fine line pattern consisting of fine metal lines.

[0062] At 20°C, one release film of a substrateless adhesive tape 1 (manufactured by Lintec Corporation, product name: MO-T015, thickness 25 μm, total light transmittance 99% or more) was peeled off and the adhesive surface was attached facing the fine line pattern formed as described above, and a roller was moved back and forth twice from above with a pressure of 2 N to form an adhesive layer, thereby obtaining an anti-counterfeiting laminate.

[0063] Example 2 A counterfeit prevention laminate was obtained in the same manner as in Example 1. The obtained counterfeit prevention laminate was attached to a cast paper (Cast 73, manufactured by Daio Paper Corporation) as an adherend to obtain an accessory for the counterfeit prevention laminate.

[0064] Comparative Example 1 An anti-counterfeit laminate was obtained in the same manner as in Example 1, except that adhesive tape 2 (manufactured by Lintec Corporation, product name: Non-Carrier PET38 PAT1 8K, thickness 20 μm) was used instead of adhesive tape 1.

[0065] Comparative Example 2 An anti-counterfeit laminate was obtained in the same manner as in Example 1, except that adhesive tape 3 (manufactured by DIC Corporation, product name: FRT30, thickness 30 μm) was used instead of adhesive tape 1. The obtained anti-counterfeit laminate was attached to coated cardboard (white coated side) as an adherend, to obtain an anti-counterfeit laminate accessory.

[0066] [Total light transmittance] The total light transmittance of each anti-counterfeit laminate and each accessory of the anti-counterfeit laminate was measured using a haze meter NDH7000 manufactured by Nippon Denshoku Industries Co., Ltd. The measurement was carried out in accordance with JIS K 7361-1:1997. The results are shown in Table 1.

[0067] [Hayes] The haze of each anti-counterfeit laminate was measured using a haze meter NDH7000 manufactured by Nippon Denshoku Industries Co., Ltd. The measurement was carried out in accordance with JIS K 7361-1:1997. The results are shown in Table 1.

[0068] [Measurement of image clarity (DOI value)] Using a Rhopoint IQ-2, the DOI values ​​of each of the anti-counterfeit laminates and anti-counterfeit laminate accessories obtained as described above were measured by irradiating light at an angle of 20 degrees from the transparent substrate surface (20 degrees from the normal direction) in accordance with a method in accordance with ASTM D5767-95 (2012). In cases where the anti-counterfeit laminate did not have an adherend, the release film on the adhesive layer of the anti-counterfeit laminate was peeled off, and the anti-counterfeit laminate was placed on a black matte sheet with the adhesive layer facing up, and the DOI value was measured from the adhesive layer side. The results are shown in Table 1.

[0069] [Authenticity Determination] The accuracy of authenticity determination was evaluated based on the following criteria. A (Excellent): The accuracy rate for each image in authenticity judgment is greater than 70% B (Good): The accuracy rate for each image is between 30% and 70%. C (Bad): The accuracy rate for each image is below 30%.

[0070] [Table 1] [Industrial Applicability]

[0071] The present invention has industrial applicability as a counterfeit prevention laminate that can be attached to an adherend and used as a seal, tag, or the like to prevent counterfeiting. [Explanation of symbols]

[0072] 10...transparent substrate, 10a...surface, 10b...surface, 20...fine line pattern, 30...adhesive layer, 100...counterfeit prevention laminate, 200...authenticity determination device, 210...irradiation device, 220...light receiving device, 230...determination unit, 300...adherend

Claims

1. A transparent substrate; a thin line pattern formed on one surface of the transparent substrate; The image clarity (DOI value) measured by irradiating the thin line pattern with light from the other surface side of the transparent substrate in accordance with ASTM D5767-95 (2012) is 70 or more. Anti-counterfeit laminate.

2. The total light transmittance of the transparent substrate is 50% or more. The counterfeit prevention laminate according to claim 1.

3. The thickness of the transparent substrate is 10 to 100 μm. The counterfeit prevention laminate according to claim 1.

4. the laminate further includes an adhesive layer covering the thin line pattern on one surface of the transparent substrate, The haze of the adhesive layer is more than 50%. The counterfeit prevention laminate according to claim 1.

5. the laminate further includes an adhesive layer covering the thin line pattern on one surface of the transparent substrate, The haze of the adhesive layer is 50% or less. The counterfeit prevention laminate according to claim 1.

6. An adherend; The anti-counterfeit laminate according to any one of claims 1 to 5 attached to the adherend, Anti-counterfeit laminate accessories.

7. The image clarity (DOI value) measured by irradiating light from the attached surface of the anti-counterfeit laminate in accordance with ASTM D5767-95 (2012) is 70 or more. The anti-counterfeit laminate accessory according to claim 6.

8. a preparation step of preparing an adherend and the anti-counterfeit laminate according to any one of claims 1 to 5; an attachment step of attaching the anti-counterfeit laminate to the adherend, In the attachment step, an anti-counterfeit laminate accessory is obtained, which has an image clarity (DOI value) of 70 or more, as measured by irradiating light from the attachment surface of the anti-counterfeit laminate using a method in accordance with ASTM D5767-95 (2012). Method for manufacturing anti-counterfeit laminate accessories.

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