JP2011235514A - Forgery/alteration preventing image formation body and image forming method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the security of personal information by enabling the addition of individual information, to a color shift material which has effect in preventing forgery or alteration made by making a copy by using a color copier or the like and whose color changes.SOLUTION: A color shift material layer is laminated over a resin base material. The resin base material is blackened by the irradiation with a laser passing through the color shift material layer. The forgery/alteration preventing image formation body comprises the resin base material which can form an image in which the color shift effect of the blackened part is made to be prominent.

Description

  The present invention relates to a method for manufacturing an ID card having a high protection function such as forgery / falsification prevention used for an ID card and having individual information such as images, letters, numbers and the like by laser light.

As a measure to prevent counterfeiting and falsification of ID cards, there is known a laser engraving method that prints individual information for each ID card by irradiating a polycarbonate substrate with laser light (YAG, CO _2, etc.). ing. In the laser printing method, the card substrate itself is cut as compared with the ink jet printing and the like, and it is difficult to tamper. However, forgery has occurred where the card base surface is scraped to erase individual information and print other information. For example, information is recorded by overwriting another image using a laser engraving apparatus or by printing or other printing methods (inkjet, laser printer, etc.).

  Method for detecting and preventing falsification by mounting personal information displayed on an IC card in an IC chip, encrypting the information in the IC chip, reading it by a reader device, analyzing the information itself, and collating it It has been known. However, falsification / counterfeiting cannot be detected in an environment without a reader device. Furthermore, if the IC chip is intentionally or accidentally destroyed, tampering or counterfeiting cannot be detected.

  It is also known to use optically variable pigments that exhibit a color shift between two different colors. Since color-shifting materials change color, they cannot be duplicated by a color copier. However, the color shift material cannot improve the security of personal information (Patent Document 1).

Japanese translation of PCT publication No. 2002-523606

  The present invention solves the problems of the prior art, and the object of the present invention is to provide a color shift with a color change that has an effect of preventing forgery and falsification by copying using a color copier or the like. It is an object of the present invention to provide a forgery / tamper-proof image forming body and an image forming method thereof that can add individual information to a material and improve the security of personal information.

As means for solving the above-mentioned problems, the invention according to claim 1 is characterized in that a color shift material layer is laminated on a resin substrate, and the color shift material layer is irradiated by laser irradiation that has passed through the color shift material layer. An anti-counterfeit / tamper-proof image forming body comprising a resin base material capable of forming an image in which a resin base material provided at a lower portion is blackened and a color shift effect of a blackened portion is remarkable.

  The invention according to claim 2 is characterized in that an OVD is partially or entirely provided on the resin base material or the color shift material layer, and the forgery / tamper-proof image forming body according to claim 1 It is.

  The invention described in claim 3 is configured such that an absorption layer is provided between the resin base material and the color shift material layer, and the counterfeiting / tampering according to claim 1 or 2 It is a prevention image forming body.

  The invention according to claim 4 is the forgery / tamper-proof image forming body according to any one of claims 1 to 3, wherein the resin base material is made of a polycarbonate resin. .

  The invention according to claim 5 is the forgery / tamper-proof image forming body according to any one of claims 1 to 4, wherein the absorption layer is a dot-like carbon ink. .

  According to the sixth aspect of the present invention, the color shift material layer and the OVD are partially or entirely laminated on the resin substrate, or the OVD is partially or entirely provided on the resin substrate, and the color shift is further performed. Laminate a material layer, or sequentially laminate an absorption layer, a color shift material layer, and OVD partially or entirely on a resin substrate, or partially or entirely laminate an absorption layer and OVD on a resin substrate. Forgery / tampering characterized in that an image is formed on a resin base material by laser irradiation on an image forming body formed by sequentially laminating a color shift material layer or laminating one of the color shift material layers. This is a prevention image forming method.

  According to the present invention, by applying a color shift material to a plastic base material and irradiating the laser through the color shift material, individual information is printed on the plastic base material, the printed portion is blackened, and the color change of the color shift material is caused. Become prominent. In addition to preventing counterfeiting by color copying, individual information can be printed. The individual print information is formed by scraping the card substrate itself, and the individual print information is formed under the color shift material layer. Therefore, it is impossible to erase the individual information by scraping the surface of the card base material, and the security can be improved.

It is the conceptual diagram which showed an example of embodiment of the image formation method which prints individual information using the image formation body and laser beam of this invention. It is the conceptual diagram which showed an example of the display form of the color shift material in the image forming body of this invention. It is the conceptual diagram which showed an example which provided OVD in the upper whole surface of the color shift material in the image forming body of this invention. It is the conceptual diagram which showed an example which provided OVD in the upper part 1 part of the color shift material in the image forming body of this invention. It is the conceptual diagram which showed an example which provided OVD in the lower whole surface of the color shift material in the image forming body of this invention. It is the conceptual diagram which showed an example which provided OVD in the lower part 1 part of the color shift material in the image forming body of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In the image forming body of the present invention, a color shift material is formed on the base material 5, and the base material 5 is blackened by the laser light 4 from the laser 7 to form the absorption layer 3. In order to use the laser beam 4 effectively, the black ink 3 may be provided in a dot pattern.

The color change of the color shift material looks noticeable when the base is black. FIG. 2 is a schematic diagram showing the color change of the printing part, but the part blackened by laser irradiation can recognize the color change. When the blackening density is weak, an absorption layer 3 that absorbs the laser light 4 may be provided. If the absorption efficiency is poor and the laser output is increased, problems such as damage to the substrate itself occur.

  The material used as the card substrate is preferably a thermoplastic resin, such as polyvinyl chloride, polyvinyl chloride-polyvinyl acetate copolymer, terephthalic acid, cyclohexanedimethanol and ethylene glycol copolymer, terephthalic acid. Amorphous polyester composed of a polymer alloy of styrene, isophthalic acid and ethylene glycol, or a copolymer of the copolymer with polycarbonate and / or polyarylate, amorphous resin such as ABS, polyethylene terephthalate, polybutylene terephthalate, Crystalline resins such as polyethylene and polypropylene can be mentioned, but polycarbonate can be preferably used and is blackened by irradiation with laser light.

  The color shift material 1 includes a liquid crystal material, a color shift ink, and a color shift film. As shown in FIGS. 3, 4, 5, and 6, an optical change device (OPTICAL) is formed on the upper surface or the lower surface of the color shift material 1. (VARIABLE EVICE: hereinafter referred to as “OVD6”) may be applied entirely or partially. Examples of the OVD 6 include a diffraction grating, a hologram, a partial vapor deposition hologram, and a laminated hologram. Examples of the diffraction grating include a relief type diffraction grating and a volume type diffraction grating.

  As OVD6, a multilayer thin film in which a high refractive index thin film having a refractive index of approximately 2.0 or more and a thin film of low refractive index material having a refractive index of approximately 1.5 are appropriately laminated with appropriate optical thicknesses, etc. Is available.

  The relief type diffraction grating has a diffraction grating recorded in the form of a fine uneven pattern on the surface thereof. Such a concavo-convex pattern is obtained by, for example, irradiating the surface of the photosensitive resin with two coherent light beams using the two-beam interference method to generate an interference pattern on the surface of the photosensitive resin. Can be formed by recording in a photosensitive resin in the form of irregularities. The interference fringes formed by the two-beam interferometry are called holograms, and any three-dimensional image can be recorded by selecting the two light beams. It is also possible to record so that different images (hereinafter referred to as changing images) can be seen depending on the viewing angle.

  The uneven pattern of the relief type diffraction grating can also be formed by irradiating the surface of the electron beam curable resin with an electron beam and exposing it to stripes constituting the diffraction grating. In this case, since the interference fringes can be controlled for each line, an arbitrary three-dimensional image or changing image can be recorded in the same manner as the hologram. It is also possible to divide the image into dot-like pixel areas, record different diffraction gratings for each pixel area, and represent the entire image with a set of these ancestors. The pixel may be a circular dot or a star-shaped dot.

  The multilayer interference film may be a metal thin film, a ceramic thin film, or a composite thin film formed by combining them with an appropriate number of layers stacked depending on the relationship between the optical characteristics of each layer and the layer combination. For example, when thin films having different refractive indexes are stacked, a high refractive index thin film and a low refractive index thin film may be combined, or a specific combination may be stacked alternately. An optical multilayer interference thin film that exhibits a desired optical effect (structural color in this case) can be obtained by an appropriate combination that satisfies the optical conditions of these layers.

Examples of materials used for such an optical multilayer interference film are given below. In addition, the numerical value in the parenthesis following the chemical formula indicates each refractive index n. First, as ceramics, Sb ₂ O ₃ (3.0), Fe ₂ O ₃ (2.7), TiO ₂ (2.6), CdS (2.6), CeO ₂ (2.3), ZnS. (2.3), PbCl ₂ (2.3), CdO (2.2), Sb
₂ O ₃ (2.0), WO ₃ (2.0), SiO (2.0), Si ₂ O ₃ (2.5), In ₂ O ₃ (2.0), PbO (2.6) , Ta ₂ O ₃ (2.4), ZnO (2.1), ZrO ₂ (2.0), MgO (1.6), Si ₂ O ₂ (1.5), MgF ₂ (1.4) , CeF ₃ (1.6), CaF ₂ (1.3 to 1.4), AlF ₃ (1.6), Al ₂ O ₃ (1.6), GaO (1.7), etc. Examples of the metal material include simple metals or alloys such as Al, Fe, Mg, Zn, Au, Ag, Cr, Ni, Cu, and Si.

  Moreover, as a low refractive index material, for example, among organic polymers, polyethylene (1.51), polypropylene (1.49), polytetrafluoroethylene (1.35), polymethyl methacrylate (1.49), Polystyrene (1.60) and the like. However, the numerical value in parenthesis shows each refractive index n here. By selecting at least one kind from these high refractive index materials or metal thin films having a light transmittance of 20 to 70% and at least one kind from low refractive index materials, and laminating them alternately at a predetermined thickness, Only a specific wavelength is absorbed or reflected.

  A multilayer thin film that generates optical wavelength interference by forming a thin film is selected from the above materials based on optical properties such as refractive index, reflectance, and transmittance, weather resistance, and interlayer adhesion. To do. As a forming method, a known method capable of controlling the film thickness, the film forming speed, the number of stacked layers, the optical film thickness and the like can be used. For example, a vacuum deposition method, a sputtering method, a CVD method, or the like. The optical film thickness is an amount given by n · d, where n is the refractive index and d is the film thickness.

  As the liquid crystal material, a composition containing a cholesteric liquid crystal compound is suitable. The composition is not particularly limited as long as it is a composition in which an iris peculiar to the cholesteric liquid crystalline compound can be seen. Among them, a composition mainly composed of a solution in which a cholesteric liquid crystalline compound is dissolved in water can be preferably used because a beautiful iris that varies depending on the viewing angle peculiar to the cholesteric liquid crystalline compound can be seen.

  In addition, the cholesteric liquid crystal layer has a helical structure in which the constituent molecules are optically active and nematically uniaxially oriented in the thin layer, but are twisted at a certain angle in a certain direction between adjacent layers. is doing. The pitch is distributed from several hundred nm to infinity. Due to this helical structure, the cholesteric liquid crystal selectively reflects light having a wavelength corresponding to the helical pitch and has a brilliant color from blue to red.

  Typical cholesteric liquid crystalline compounds include cholesteryl benzoate, cholesteryl chloride, cholesteryl octoate, cholesteryl nonanoate cholesteryl carbonate, oleyl cholesteryl carbonate, cholesteryl acetate, cholesteryl acetate, and liquid crystal oligomers, liquid crystal polymers, etc. Can be illustrated. Examples of cholesteric liquid crystalline compounds include hydroxyalkyl celluloses such as hydroxypropyl cellulose (HPC), hydroxyethyl cellulose, and hydroxybutyl cellulose, and acyl derivatives thereof.

  Examples of the powder that can see different colors depending on the observation angle include layered substances such as mica. A powder obtained by coating this mica with reduced titanium dioxide or iron oxide can be used. These exhibit chromatic dispersion performance by the so-called flip-flop effect. These powders can be converted into inks, and a layer having wavelength dispersion performance can be formed by a known printing method or coating method.

The color shift film has a layer that changes the display color according to the observation angle based on diffraction, interference, or selective reflection. For example, the surface is covered with a metal oxide mainly composed of titanium oxide and / or iron oxide. The optical interference film is formed by laminating a plurality of natural mica particles and a plurality of inorganic oxides having different refractive indexes, and is formed by a coating method such as a gravure method or a roll coating method, or a vapor deposition method such as a vacuum vapor deposition method.

  The absorption layer 3 absorbs the illumination light transmitted through the color shift material 1. By providing the absorption layer 3, the reflected light from the color shift material 1 can be more easily visually recognized. Therefore, the above-mentioned optical effect exhibited by the color shift material 1 becomes more remarkable, and the forgery prevention effect can be improved.

1. Color shift material 2. Black ink (halftone dot)
3 ... Absorbing layer 4 ... Laser beam 5 ... Base material 6 ... OVD
7. Laser device A ... Color shift image B ... Color shift image

Claims (6)

  The color shift material layer is laminated on the resin base material, and the resin base material provided at the bottom of the color shift material layer is blackened by the laser irradiation that has passed through the color shift material layer. An anti-counterfeit / tamper-proof image forming body comprising a resin base material capable of forming a prominent image.   2. The forgery / tamper-proof image forming body according to claim 1, wherein OVD is partially or entirely provided on the resin base material or the color shift material layer.   The forgery / tamper-proof image forming body according to claim 1, wherein an absorption layer is provided between the resin base material and the color shift material layer.   The counterfeit / tamper-proof image forming body according to any one of claims 1 to 3, wherein the resin base material is made of a polycarbonate resin.   The forgery / tamper-proof image forming body according to any one of claims 1 to 4, wherein the absorbing layer is a dot-like carbon ink.   A color shift material layer and OVD are partially or entirely laminated on a resin substrate, or a OVD is partially or entirely laminated on a resin substrate and a color shift material layer is further laminated, or a resin substrate The absorption layer, the color shift material layer, and the OVD are sequentially laminated on a part or the whole of the surface, or the absorption layer and the OVD are provided on the resin base material on a part or the whole, and the color shift material layer is sequentially laminated. Alternatively, a forgery / tamper-proof image forming method comprising forming an image on a resin base material through a color shift material layer by laser irradiation on an image forming body formed by laminating one of them.

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