JP2016147392A - Forgery preventive printed matter and authenticity discrimination method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forgery preventive printed matter in which stable detection can be performed while substantially avoiding influences of optical characteristics of a substrate, and a forgery prevention effect of the printed matter can be detected with a small-scale facility.SOLUTION: The forgery preventive printed matter includes a printed image region described below on at least a part of a substrate. The printed image region is composed of: a first printed layer formed of a first ink in a dark color comprising a pigment having infrared ray absorption characteristics or infrared ray non-absorption characteristics; and a second printed layer formed of a second ink comprising a visible light-excited fluorescent light-emitting pigment and a brilliant material to entirely cover the first printed layer.SELECTED DRAWING: Figure 1

Description

  In the field of valuable printed matter such as banknotes, passports, securities, identification cards, cards, and passports that require an anti-counterfeit effect, the present invention displays images that are visible under a predetermined light source. The present invention relates to an anti-counterfeit printed matter and an authenticity determination method.

  Anti-counterfeiting technology is required to prevent duplication and forgery of valuable printed matter such as banknotes, passports, securities, identification cards, cards, and passports. For this reason, such precious printed materials include inks containing special glittering materials such as interference mica, oxidized flake mica, pigment-coated aluminum flakes, and optically variable flakes that are difficult to reproduce on a copying machine, and specific wavelengths. Printing is performed with ink mixed with fluorescence or phosphorescence that emits light, and copy prevention and authenticity determination are performed.

  As an example, genuine and counterfeit products are formed by forming characters or designs (patterns) with process color ink on a printing layer formed with an ink containing a pearl pigment and a fluorescent pigment on a base material by offset printing. Has been disclosed (see, for example, Patent Document 1).

  Further, on the substrate, on the photoreactive printing layer formed in the same color as the base material that emits fluorescence when irradiated with ultraviolet rays or infrared rays, at least a part inside the outer peripheral portion of the photoreactive printing layer is exposed. An anti-counterfeit printing medium is disclosed in which a color variable printing layer is provided that changes the visible color depending on the viewing angle (see, for example, Patent Document 2).

JP 2002-285061 A Japanese Patent No. 5034499

  However, since the techniques described in Patent Document 1 and Patent Document 2 form a print layer with a pattern (design) on a print layer formed with an ink containing a fluorescent pigment, the optical characteristics of the substrate For example, due to infrared absorption characteristics, infrared reflection characteristics, or infrared transmission characteristics, the fluorescence emission of the photoreactive layer is absorbed or transmitted by the base material, so that there is a problem that stable detection cannot be performed. The infrared reflection characteristics and infrared transmission characteristics are hereinafter referred to as “infrared non-absorption characteristics”.

  In addition, since the techniques described in Patent Document 1 and Patent Document 2 use infrared rays or ultraviolet rays as an irradiation light source, they are easily affected by disturbance light, and it is necessary to provide the above-described irradiation light source shielding equipment. There was a problem that the equipment would be large.

  The present invention aims to solve the above-described problems, is less susceptible to the optical characteristics of the substrate, can be stably detected, and can detect the forgery prevention effect of printed matter with a small facility. It is a method that can be performed.

  The anti-counterfeit printed matter of the present invention includes a visible light-excited fluorescent light-emitting pigment and a glitter so as to cover all of the first printed layer formed with the first ink and the first printed layer on at least a part of the substrate. It is characterized by comprising a printed image area comprising a second printed layer formed of a second ink containing a functional material.

  The first ink of the anti-counterfeit printed matter of the present invention is a dark color system and has an infrared absorption characteristic or an infrared non-absorption characteristic.

  The excitation wavelength range of the visible light excitation fluorescent pigment of the anti-counterfeit printed matter of the present invention is 545 to 610 nm, and the emission wavelength has at least a peak wavelength at 980 nm.

  The method for determining authenticity of a forgery-preventing printed material according to the present invention includes an irradiation step of irradiating a printed image region with visible light having a main wavelength region of 545 to 610 nm, and an infrared region where the visible light emitted from the irradiation step is emitted. A detection step of detecting only a print image region having a wavelength region longer than 856 nm, and a determination step of visualizing and displaying the print image region in a wavelength region longer than 856 nm and determining whether the print image region is authentic by at least the presence or absence of the print image. This is a method for determining authenticity of a forgery-preventing printed material.

  The anti-counterfeit printed matter of the present invention is a print formed with an ink containing a visible excitation fluorescent pigment in pearl ink on a print layer formed with a dark-colored first ink having infrared absorption characteristics or non-infrared absorption characteristics. Since the layers are stacked, the fluorescence emission is hardly affected by the optical characteristics of the substrate, and stable detection is possible.

  In addition, since the authenticity determination method of the present invention uses visible light as an irradiation light source, it is not easily affected by disturbance light, and it is not necessary to provide a shielding facility, so that it can be a small facility.

Schematic diagram of anti-counterfeit printed matter in the present invention Schematic which shows the structure of the forgery prevention printed matter in this invention. Schematic showing the first print layer Schematic showing the second printed layer Schematic showing the observation state under a normal light source Schematic showing the observation state under a specific visible light source Authenticity discrimination method of the present invention Luminous characteristics of illumination light source Schematic diagram of authenticity determination method of the present invention Schematic diagram of anti-counterfeit printed matter of Example 1 Schematic which shows the observation state under the normal light source of Example 1. Schematic which shows the authenticity determination method of Example 1 Schematic which shows the observation state under the specific light source of Example 1. Schematic diagram of anti-counterfeit printed matter of Example 2 Schematic which shows the observation state under the normal light source of Example 1. Schematic which shows the observation state under the specific light source of Example 1.

  DESCRIPTION OF EMBODIMENTS Embodiments for carrying out the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments described below, and includes various other embodiments within the scope of the technical idea described in the scope of claims.

(Forgery prevention printed matter)
In FIG. 1, the forgery prevention printed matter (1) in this invention is shown. 1A is a front view of the anti-counterfeit printed matter (1), and FIG. 1B is a cross-sectional view of the anti-counterfeit printed matter (1) along the line AA ′. The anti-counterfeit printed matter (1) is formed by forming a print image region (3) on at least a part of the base material (2). In FIG. 1, it is formed on almost the entire surface of the base material (2), but may be formed on a part of the base material (2). Information necessary for printed matter such as letters and numbers may be described. The base material (2) may be paper, plastic, metal or the like as long as it does not affect the optical characteristics of irradiation light and fluorescence emission, which will be described later. The color of the substrate (2) may be any color as long as it does not affect the optical characteristics of irradiation light and fluorescence emission, which will be described later, and may be transparent or translucent. There is no restriction | limiting in particular also about the magnitude | size of a base material (2). Although the base material (2) reflects 545 to 610 nm in the visible light region, which is excitation light described later, the visible light region cannot pass through a filter that transmits a wavelength region longer than 856 nm in the infrared region. It is visually recognized at a density close to black or black.

  An outline of the configuration of the print image area (3) of the present invention is shown in FIG. The print image area (3) is formed by laminating the second print layer (5) on the first print layer (4) formed on the substrate (2). The laminated structure of the two print layers must be a layer structure in which the second print layer (5) overlaps the first print layer (4). In the present embodiment, the area of the second print layer (5) is larger than the area of the first print layer (4), but the second print layer (5) is the first print layer ( 4), the area of the first print layer (4) and the second print layer (5) may be the same. Moreover, if the shape of the 2nd printing layer (5) is the structure which covers all the 1st printing layers (4), the same shape or a different shape may be sufficient as it. The second printed layer (5) covers the entire first printed layer (4) at the time of irradiation with visible light having a main wavelength region of 545 to 610 nm in the visible light region described later, When only the wavelength region longer than 856 nm in the infrared region irradiated with visible light is detected, the substrate (2) has a density close to black or black, infrared absorption or infrared non-absorption characteristics, and the first printed layer. (4) is lower than the density at which the substrate (2) is visually recognized or a density close to black, for example, gray, and the region of only the second printed layer (5) having a visible light-excited fluorescent pigment is Three layers including the base material (2) because the light is visible from light gray to white, which is lower than the density at which the base material (2) or the first printed layer (4) is visible by infrared emission. Is true because the difference in brightness of achromatic colors is large and the distinction between the three layers is clear. Discrimination is because it becomes easy.

First, the first print layer (4) will be specifically described. Shown in FIG. 3 is the first printed layer (4). The first printed layer (4) is formed on the base material (2) with a dark-colored first ink containing a color material having infrared absorption characteristics or non-infrared absorption characteristics. A color material having infrared absorption characteristics includes carbon black.

However, it is not limited to this as long as it is a color material (in particular, ink) that absorbs light in the infrared region. For example, organic dyes having absorption in the infrared region include polymethylene, phthalocyanine, azo, and anthraquinone compounds, and inorganic infrared absorbers include antimony-doped tin oxide and tin-doped indium oxide. . Examples of the color material having non-infrared absorption include white pigments such as titanium oxide, magnesium carbonate, and barium sulfate. The color of the first printed layer (4) is black or a hue that does not deviate from black, for example, slightly light black, gray, brown, dark green, dark blue, purple, deep red, etc., and has high absorption of visible light. It is a dark color system, and black is particularly good. The dark color system means Munsell brightness 1, 2, and 3 (Reference: “Now pass! Color Coordinator Level 2”, Takahashi Shoten, Yasue Togaikawa, described on P229). At the same time, only the light having a specific wavelength in the visible light region is reflected by the second printed layer (5), and the light transmitted through the second printed layer (5) is applied to the first printed layer (4). Since it is not absorbed and reflected, the effect of pearl ink is emphasized and visibility is improved. The reason why black is particularly good is that it has the highest absorption of visible light. In addition, the dark first ink containing a coloring material having infrared absorption or non-infrared absorption characteristics emits light when irradiated with visible light having a main wavelength region of 545 to 610 nm, which will be described later. When only the wavelength region longer than 856 nm in the infrared region is detected, it is visually recognized as black or a density close to black. In the present invention, a visible-light-excited fluorescent light-emitting pigment and glitter are formed on the first printed layer (4) printed with a dark-colored first ink containing a colorant having infrared absorption or non-infrared absorption characteristics. In order to form the 2nd printing layer (5) printed with the 2nd ink containing material, it receives under the influence of the 2nd ink containing a visible light excitation fluorescent luminescent pigment or a glittering material, 545 mentioned later When visible light having 610 nm as the main wavelength region was irradiated, and only the wavelength region longer than 856 nm in the infrared region emitted by the visible light was detected, the base material (2) was approximated to black or black where the base material (2) was visually recognized. It is visually recognized lower than the concentration, for example, gray.

  Next, the second print layer (5) will be described. Here, for convenience of explanation, the first print layer (4) is indicated by a dotted line. Shown in FIG. 4 is a second printed layer (5). The second printed layer (5) is formed of a second ink containing a visible light excitation fluorescent pigment and a glittering material. The visible light excited fluorescent luminescent pigment is a material that is excited by the wavelength range of visible light and has a main emission peak wavelength in the range of 800 nm to 1020 nm, the wavelength range of visible light is 545 to 610 nm, and the main emission peak wavelength is It is desirable that it is 980 nm. If it is the wavelength range of visible light mentioned above, it is hard to receive the influence of disturbance light, and has little influence on the vision with respect to a human body. If the main light emission peak wavelength is 980 nm, since it can be detected by a commercially available infrared sensor, versatility is enhanced. The color and blending amount of the visible light-excited fluorescent luminescent pigment itself may be set as appropriate as long as they do not affect the color characteristics of the glittering material. The “color” in the present invention represents a color including the concepts of hue, saturation, and brightness. In addition, the second ink containing a visible light-excited fluorescent pigment and a glittering material is a red ink that emits light when irradiated with visible light when irradiated with visible light having a main wavelength region of 545 to 610 nm in the visible light region described later. When only the wavelength region longer than 856 nm is detected in the outer region, the light is visible from light gray to white, which is lower than the density at which the base material (2) or the first printed layer (4) is visually recognized.

  The glittering material is a material that has a specific color or is transparent or translucent under diffuse reflected light, and has a light-dark flip-flop property and / or a color flip-flop property. In the present invention, “light / dark flip-flop property” refers to a property in which only the brightness of a material changes when light is incident on the material, and “color flip-flop property” refers to a property in which light is incident on a material. It refers to the property of changing the hue of a substance. Examples of inks used in printing having light and dark flip-flop properties include metallic metallic pigments such as gold and silver. Examples of materials having color flip-flop properties include pearl pigments, liquid crystal inks, OVI (Optical variable Ink), and CSI (Color Shifting Ink). Many inks have an object color, while iris pearl ink is colorless and transparent. For example, a red iris pearl ink is colorless and transparent under diffuse reflection light, but emits a red interference color under regular reflection light. As described above, the ink having the “color flip-flop property” changes in hue under specular reflection light.

  As shown in FIG. 4, the design of the first printed layer (4) and the second printed layer (5) configured as described above is such that the second printed layer (5) is the first printed layer (4 ) May be laminated. The first print layer (4) and the second print layer (5) do not need to be formed by solid printing, and may form characters, figures, symbols, etc. by image lines or halftone dots. The printing method is not particularly limited, and can be formed by image lines or pixels by a known printing method such as screen printing, intaglio printing, gravure printing, flexographic printing, letterpress printing, or IJP. Note that the image line in the present invention is a dotted line or a broken line, a straight line, a curved line, and a broken line in which halftone dots, which are small dots of a minimum unit forming a printed image, are continuously arranged in a specific direction by a certain distance The pixel is a circle, a triangle, a polygon including a rectangle, a star, or other various figures, or a character, a symbol, a number, or the like.

  Next, the effect of the anti-counterfeit printed matter (1) of the present invention will be described with reference to FIG. As shown in FIG. 5A, under the normal light source (6), for example, when the iris pearl ink is used, in the diffuse reflection state, the second printed layer (5) becomes colorless and transparent, and the observer (7 ) Is visible only in the first printed layer (4). In addition, as shown in FIG. 5B, in the state of regular reflection, the second printed layer (5) changes color depending on the specific interference color of the pearl ink at the observation angle. Moreover, the color change of the 2nd printing layer (5) laminated | stacked on the dark-colored 1st printing layer (4) can be visually recognized more notably.

  Next, the effect of irradiating visible light with a predetermined wavelength will be described. A specific method will be described later. As shown in FIG. 6, when the visible image light having a wavelength in the visible light region excited by the visible light-excited fluorescent light-emitting pigment contained in the second ink is irradiated and the printed image region (3) is observed with an infrared camera, it is visible. The second print layer (5) emits infrared light by the photoexcited fluorescent light-emitting pigment, but infrared light is absorbed by the infrared absorption characteristics of the first print layer (4), and the gray first print layer (4 ) And the second print layer (5) that emits infrared light can be visually recognized.

(Authentication method)
As shown in FIG. 7 as an example, the printed matter authenticity determination method of the present invention is an irradiation step (S1) of irradiating the print image region (3) with visible light having a main wavelength region of 545 to 610 nm, and an irradiation step. A detection step (S2) for detecting only a print image region having a wavelength longer than 856 nm in the infrared region emitted by emitting visible light by (S1), a result detected by the detection step (S2), and a length longer than 856 nm This is a method for determining authenticity of a forgery-preventing printed matter characterized by comprising a determination step (S3) for visualizing a print image region in a wavelength region and determining whether the image is authentic by the presence or absence of the print image.

  An irradiation process (S1) irradiates the printing image area | region (3) with visible light which makes 545-610 nm a main wavelength range. The light source of the irradiation light is not particularly limited as long as the light amount of the main wavelength that excites the light emitter of the discrimination target printed matter is sufficient, and a known LED or LD can be used. In addition, the main wavelength (center wavelength) of the light source in the present invention means a wavelength having the highest irradiation intensity when the light emitted from the light source is dispersed. As an example, it is LED which has a light emission characteristic as shown in FIG. 8, and based on the above-mentioned definition, the main wavelength (9) (center wavelength) of this LED is 590 nm.

  In the detection step (S2), an infrared emission image is taken by an infrared camera, or a main emission wavelength range of 800 nm to 1020 nm, which is an infrared emission of the print image area (3), is received and received by photoelectric conversion. Output the quantity as an output waveform. As a detector of the infrared information reader used in the detection step (S2), a Si photodiode, an InGaAs diode, a photomultiplier, an image intensifier, or the like can be used. When the luminous intensity of the illuminant is low, a highly sensitive photoelectric conversion sensor such as a photomultiplier or an image intensifier is used. Moreover, you may detect with a well-known infrared camera. In front of the incident light portion of the detector, a long-pass filter that removes light from the excitation light source and removes light having a wavelength unnecessary for detection, for example, transmits a wavelength longer than 856 nm is used.

  The discrimination step (S3) is a discrimination step for visualizing and displaying the print image area in the wavelength range longer than 856 nm taken from the detection step (S2) and judging whether the print image area is authentic or not. Furthermore, in order to perform true / false discrimination with higher accuracy, the output waveform formed in the detection step (S2) is compared with a reference waveform that is a predetermined set value or a reference pattern, and is matched with the shape of the reference waveform. Those that match can be identified as authentic. For example, if a permissible range is set as a reference value ± error centered on a preset reference value, and an identification waveform obtained from the discrimination target print is obtained between the maximum allowable value and the minimum allowable value, the discrimination target print is It is determined to be authentic. Alternatively, the infrared image captured in the detection step (S2) may be pattern-matched with a reference infrared image that is a predetermined genuine object, and the matched image may be determined as a genuine object. As for pattern matching, there is a possibility that a perfectly matched infrared image may not be formed due to the overlapping state of both infrared images. Judgment criteria may be set. Here, the threshold value may be set as appropriate.

  Next, the discrimination device (10) that performs the true / false discrimination of the anti-counterfeit printed matter (1) of the present invention will be described with reference to the schematic diagram of FIG. The discriminating device (10) includes an infrared camera (12) equipped with an LED that is a visible light source (8) having a main wavelength of 590 nm, a long-pass filter (11) that transmits a wavelength longer than 856 nm, and a detected infrared image. It is the structure which consists of the information equipment (13) which visualizes and displays. Using the discrimination device (10) of the present embodiment, the authenticity discrimination is performed by irradiating the anti-counterfeit printed matter (1) with excitation light according to the above-described authenticity discrimination method.

  Hereinafter, examples of the anti-counterfeit printed matter specifically produced according to the above-described embodiment will be described in detail, but the present invention is not limited to these examples.

  FIG. 10 shows an anti-counterfeit printed matter (1 ′) in Example 1. As shown in FIG. 10A, the forgery-preventing printed matter (1 ′) is formed by forming a print image region (3 ′) on a white substrate (2 ′). As the base material (2 ′), general white fine paper (manufactured by Shiraoi Nippon Paper Industries Co., Ltd.) was used.

  Next, the dark-colored first ink having infrared absorption characteristics and the second ink containing the visible light excitation fluorescent light-emitting pigment and the glittering material used in Example 1 will be described. A black process ink manufactured by T & K was used as the first dark ink having infrared absorption characteristics. The glittering material of the second ink uses iriidine, and the visible light excitation fluorescent luminescent pigment uses an infrared luminescent pigment having a wavelength range of the visible light to be excited of 545 to 610 nm and a main emission peak wavelength of 980 nm. . The composition of each ink was as shown in Table 1. The blending of the second ink is not limited to that in Table 1, and the blending of the visible light excited fluorescent light-emitting pigment can be adjusted within a range that does not impair the optical properties of the glittering material. Specifically, the visible light excitation fluorescent luminescent pigment may be about 10 parts by weight.

  As shown in FIG. 10B, the print image area (3 ′) includes a first print layer (4 ′) formed of a dark first ink containing a color material having infrared absorption characteristics. The second printed layer (5 ') is formed on the first printed layer (4') by a second ink containing a visible light-excited fluorescent pigment and a glittering material. As shown in FIG. 10C, the first printed layer (4 ′) was formed by solid printing (4′a) with a dot area ratio of 100% using the infrared absorption characteristics shown in Table 1. Moreover, as shown in FIG.10 (d), the 2nd printing layer (5 ') was formed by the solid printing (5'a) of the mesh 225PW using the 2nd ink. The first printing layer (4 ′) is printed on the substrate (2 ′) by the offset printing method, and the second printing layer (5 ′) is printed by the first printing layer (4 ′) by the screen printing method. 4 ′) was printed on to form a print image area (3 ′).

  As shown in FIG. 10B, the anti-counterfeit printed matter (1 ′) includes a first printed layer (4 ′) printed with a dark-colored first ink containing a color material having infrared absorption characteristics; The second printing layer (5 ′) printed with the second ink containing the visible light excitation fluorescent pigment and the glittering material is laminated on the first printing layer (4 ′). As shown in FIG. 11, under the diffuse reflected light under the normal light source (6 ′), the second printed layer (5 ′) becomes colorless and transparent, and the observer (7 ′) gives the first printed layer (4 ′). ′) Was only visible. On the other hand, as shown in FIG. 11B, under the specular reflection light, the second printed layer (5 ′) changes color depending on the specific interference color. The color change of the 2nd printing layer (5 ') laminated | stacked on the 1st printing layer (4') was able to be visually recognized more notably.

  Next, the authenticity determination method of the forgery-preventing printed matter (1 ′) will be described.

  For the authenticity determination method, a determination device (10 ′) shown in FIG. 12 was used. As the visible light source (8 ′) in the irradiation step (S1), an LED having a main wavelength of 590 nm shown in FIG. 8 was used. As a detector in the detection step (S2), an infrared camera (12 ′) provided with a long pass filter (11 ′) that transmits a wavelength longer than 856 nm was used. The discriminating means in the discriminating step (S3) uses the information device (13 ′) and judges whether or not the image is authentic by the presence or absence of the infrared image of the print image area (3 ′) detected by the infrared camera (12 ′). did. Furthermore, in order to perform authenticity determination with higher accuracy, it is determined that an image that has been matched by pattern matching with a predetermined infrared image of an authentic printed product is determined to be authentic.

  As shown in FIG. 12, the anti-counterfeit printed matter (1 ′) is irradiated with visible light having a main wavelength of 590 nm from an LED that is a visible light source (8 ′), and the long-pass filter that transmits reflected light of infrared rays of 856 nm or more ( 11 ′), the image was taken with an infrared camera (12 ′). As shown in FIG. 13, the base portion (2 ′) was black, and the first printed layer portion (4 ′) made of infrared absorbing ink. ) Was gray, and the second printed layer portion (5 ') was white, and each was projected on the monitor. The print image area (3 ′) including the portion (5 ′) of the second print layer, which was not visible under normal light sources, is the gray first print layer (4 ′) and infrared in the infrared image. A print image area (3 ′) composed of the second print layer (5 ′) with white light emission could be detected. The print image area was visualized and displayed, and whether or not it was authentic was determined by the presence or absence of the print image. Furthermore, in order to perform authenticity determination with higher accuracy, a comparison between the infrared image of the authentic printed matter stored in advance and the infrared image of the first embodiment is performed by pattern matching in the information device (13 ′) which is a determination process, Since it matched with a genuine printed matter, it was determined that the anti-counterfeit printed matter (1 ′) was a genuine product.

  Example 2 will be described. In contrast to Example 1 using ink having infrared absorption characteristics, Example 2 uses ink having infrared non-absorption characteristics. FIG. 14 shows an anti-counterfeit printed matter (1 ″) in Example 2. As shown in FIG. 14A, the forgery-preventing printed matter (1 ″) is formed by forming a print image region (3 ″) on a white base material (2 ″). As the base material (2 ″), general white fine paper (manufactured by Shiraoi Nippon Paper Industries Co., Ltd.) was used.

  Next, the dark process ink having infrared non-absorption characteristics and the second ink containing a visible light excitation fluorescent pigment and a glittering material used in Example 2 will be described. A process ink manufactured by T & K was used as the first dark ink having infrared non-absorbing properties. For the glittering material of the second ink, iriidine is used, and for the visible light excitation fluorescent light emitting pigment, an infrared light emitting pigment having a wavelength range of visible light to be excited of 545 to 610 nm and a main light emission peak wavelength of 980 nm is used. used. The composition of each ink was as shown in Table 2.

  As shown in FIG. 14B, the print image area (3 ″) includes a first print layer (4 ′) formed with a dark-colored first ink containing a color material having infrared non-absorbing characteristics. ′) And a second printed layer (5 ″) formed of a second ink containing a visible light-excited fluorescent pigment and a glittering material on the first printed layer (4 ″). As shown in FIG. 14 (c), the first printed layer (4 ″) was formed using a first ink having infrared non-absorbing characteristics shown in Table 2 and having a dot area ratio of 100% (4 ″ ″ B). Moreover, as shown in FIG.14 (d), the 2nd printing layer (5 '') was formed by the line (5''b) using the 2nd ink. The first printing layer (4 ″) is printed on the substrate (2 ″) by the offset printing method, and the second printing layer (5 ″) is printed by the screen printing method. Printing was performed on the layer (4 ″) to form a print image area (3 ″).

  As shown in FIG. 14B, the anti-counterfeit printed matter (1 ″) is a first printed layer (4 ″) printed with a dark first ink containing a coloring material having infrared non-absorbing properties. ) And a second printed layer (5 ″) printed with a second ink containing a visible light-excited fluorescent light-emitting pigment and a glittering material, is laminated on the first printed layer (4 ″). is there. As shown in FIG. 15 (a), the second printed layer (5 ″) becomes colorless and transparent under diffuse reflected light under a normal light source (6 ″), and the observer (7 ″) Only one printed layer (4 ″) was visible. On the other hand, as shown in FIG. 15B, under the specular reflection light, the second printed layer (5 ″) changes color depending on the specific interference color. The color change of the 2nd printing layer (5 '') laminated | stacked on the 1st printing layer (4 '') of a type | system | group has been visually recognized more notably.

  Next, the authenticity determination method of the forgery prevention printed matter (1 ″) will be described. In addition, the description similar to Example 1 is abbreviate | omitted and only a different location is demonstrated.

  As the authenticity determination method, the same method as in Example 1 was used. As shown in FIG. 16, the anti-counterfeit printed matter (1 ″) is irradiated with visible light having a main wavelength of 590 nm from the LED that is the visible light source (8 ′), and the long-pass filter transmits the reflected light through the infrared rays of 856 nm or more. As shown in FIG. 16, the base material portion (2 ″) is black and is a portion of the first printed layer made of non-infrared absorbing ink. (4 ″) was gray and the second printed layer portion (5 ″) was projected on a monitor as white, black and gray lines. The print image area (3 ″) including the portion (5 ″) of the second print layer, which was not visible under a normal light source, is a gray first print layer (4 ″) that is an infrared image. In addition, a print image region (3 ″) composed of the second print layer (5 ″) having a white line with infrared emission was detected. The print image area was visualized and displayed, and whether or not it was authentic was determined by the presence or absence of the print image. Further, in order to perform authenticity determination with higher accuracy, a comparison between the infrared image of the authentic printed matter stored in advance and the infrared image of the present embodiment 2 is performed by pattern matching in the information device (13 ′) which is a determination process, Since it matched with a genuine printed matter, it was determined that the anti-counterfeit printed matter (1 ″) was a genuine product.

(Verification example)
Next, using the color copy machine (imagePRESS C1 +, manufactured by Canon Inc.) as a genuine copy of the anti-counterfeit printed matter (1 ′, 1 ″) of Example 1 and Example 2, the anti-counterfeit printed matter (1 ′, 1 ″). ″) Is used for the verification printed matter (not shown) produced by copying, and the discrimination device (10 ′) shown in FIG. 12 is used, and in the irradiation step (S1), visible light having a main wavelength of 590 nm is emitted. The reflected light was photographed with an infrared camera (12 ′) through a long pass filter (11 ′) that transmits infrared light of 856 nm or more.

  The printed matter of the verification example does not show the infrared image of the anti-counterfeit printed matter (1 ′, 1 ″), and the anti-counterfeit effect exhibited by the present invention can be verified on the printed matter for verification. There wasn't.

(Comparative example)
Next, as a comparative example, as shown in FIG. 10 of Example 1, the light emission characteristics were exhibited on the first printed layer (4 ′) printed with the black ink having infrared absorption characteristics on the base material (2 ′). A comparative printed matter (not shown) in which the second printed layer (5 ′) printed with the glitter ink that does not have is laminated will be described. The composition of each ink is shown in Table 3, and the printing conditions such as the base material used, the printing method, and the dot area ratio are the same as in Example 1, and will be omitted.

  When the comparative printed material was observed with the naked eye under both diffuse reflection light and regular reflection light under a normal light source, the effects shown in the paragraph (0034) described above could be confirmed. However, when the discriminating device (10 ′) shown in FIG. 12 is used, the second printed layer (5 ′) does not emit infrared light and becomes black as a whole. When pattern matching was performed with the information device (13 ′), which is a discrimination process, for comparison with the stored infrared image of the genuine print product, the print product did not match the authentic print product, and therefore the comparative print product was determined not to be a genuine product.

  According to the authenticity determination method of the present invention, a single wavelength light source and one infrared information reader are used as described above, and the print image area (3 ′, 3 ″), By verifying the infrared image by the printing layers (4 ′, 4 ″) and the second printing layers (5 ′, 5 ″), it was possible to easily determine whether the images were true or false.

1, 1 ′, 1 ″ anti-counterfeit printed matter 2, 2 ′, 2 ″ base material 3, 3 ′, 3 ″ print image area 4, 4 ′, 4 ″ first print layer 5, 5 ′, 5 ″ Second printed layer 6, 6 ′, 6 ″ Normal light source 7, 7 ′, 7 ″ Observer 8, 8 ′ Visible light source 9 Main wavelength of irradiation light 10, 10 ′ Discriminating device 11, 11 ′ Long pass filter 12, 12 'Infrared camera 13, 13' Information equipment

Claims (4)

On at least part of the substrate,
A first printed layer formed by the first ink;
A print image region comprising a second print layer formed of a second ink containing a visible light-excited fluorescent light-emitting pigment and a glittering material is provided so as to cover all of the first print layer. Anti-counterfeit printed matter.   The forgery-preventing printed matter according to claim 1, wherein the first ink is a dark color system and has an infrared absorption characteristic or an infrared non-absorption characteristic.   The forgery-preventing printed matter according to claim 1 or 2, wherein the visible light excitation fluorescent pigment has an excitation wavelength range of 545 to 610 nm and an emission wavelength of at least a peak wavelength of 980 nm. A method for determining a forgery-proof printed matter according to any one of claims 1 to 3,
An irradiation step of irradiating the printed image region with visible light having a main wavelength region of 545 to 610 nm;
A detection step of detecting only the printed image region in a wavelength region longer than 856 nm in an infrared region emitted by emitting visible light by the irradiation step;
A method for determining authenticity of a forgery-preventing printed material, comprising a determining step of visualizing and displaying a print image region in a wavelength region longer than 856 nm and determining whether or not the image is authentic based on the presence or absence of a print image.

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