JP6216974B2 - Anti-counterfeit printed matter - Google Patents

Description

  In the field of valuable printed matter such as banknotes, passports, securities, identification cards, cards, and passports, which are security printed matters that require anti-counterfeiting effects, the present invention transmits images that have been viewed under reflected light. It relates to anti-counterfeit printed matter that disappears under light.

  With recent developments in digital devices such as scanners, printers, and color copiers, it has become possible to easily produce elaborate copies of precious printed matter. Therefore, in order to prevent duplication and forgery as described above, various anti-counterfeit technologies that cannot be reproduced by a printer or a copier are required.

  As one of the anti-counterfeiting techniques, there is a so-called watermarking technique in which a pattern is formed by the thinness of the paper and the density of the fibers so that the pattern is visually recognized under transmitted light. This watermark technology is a technology that can authenticate in any environment as long as there is more than a certain amount of light, and it is also a classic technology that has existed since ancient times because it is well known. Nevertheless, it is still used on banknotes around the world.

  Since the watermark technology must be formed at the paper manufacturing stage, it cannot be manufactured by a paper manufacturer. In addition, even if the paper manufacturer manufactures it, there is a problem that the manufacturing cost increases. As a method for reproducing the image, there is a forgery prevention technique in which a transmission image corresponding to the watermark is formed by printing using a special penetrating ink in a printing process (see, for example, Patent Document 1).

  However, regarding anti-counterfeiting technology for authenticating a transmitted image corresponding to a watermark printed using penetrating ink, penetrating ink itself is commercially available from many manufacturers and can be easily obtained even by ordinary people. For this reason, there is a problem that it is easy for a counterfeiter to produce.

  In order to solve such a problem, the present applicant has developed a special and complicated combination of a colored penetrating ink in which a coloring material is mixed with a penetrating ink and an ordinary colored ink paired with the colored penetrating ink as a pair ink. A transparent latent image printed matter that forms an image with a halftone dot structure and is different from the image that can be observed under reflected light and the image that can be observed under transmitted light. An application has been filed (for example, see Patent Document 2).

JP-A-6-228900 JP 2012-223905 A

  The technique described in Patent Document 2 is a technique in which a colored penetrating ink obtained by adding a coloring material to a penetrating ink having a penetrating component is used to form an image having a density that can be seen even under visible light as one configuration of the invention. is there. In this technique, an image formed with a colored penetrating ink exhibits an effect that the color changes lightly under transmitted light. However, an image formed with the colored penetrating ink used in the technique of Patent Document 2 changes lightly, but has not yet achieved an effect that the image itself disappears completely.

  Whether the image is visible or not visible is easily verbalized and can be easily determined by everyone, but the degree of lightness and shade of the image (lightness level) It is difficult to verbalize properly. A dedicated measuring instrument is required to show the light and shade in absolute quantities such as reflection density and brightness. For this reason, in the technique of Patent Document 2, the density change itself under transmitted light of an image formed with colored penetrating ink is not used as a criterion for authenticity discrimination, and the difference in density under transmitted light between paired inks. The latent image is made to appear by the method of relativizing the images, and whether or not the latent image appears is used as a criterion for authenticity determination. As described above, since the performance of the color penetrating ink itself is low in the technology of Patent Document 2, it is necessary to have a complicated halftone dot configuration and advanced printing in order to make sure the authenticity is true. There was a problem.

  In addition, an image formed using colored penetrating ink in the technique of Patent Document 2 requires an information part representing significant information and a background part surrounding the background. Under reflected light, the background part Therefore, there is a problem in that the presence of the image quality lowers the contrast of the information portion and the visibility is lowered.

  Further, the colored penetrating ink used in the technique of Patent Document 2 needs to be prepared by mixing a certain proportion of coloring material with penetrating ink. Since such a color penetrating ink is not commercially available, it is impossible for only those who have knowledge and facilities for ink preparation to prepare it, and there is a problem that ink preparation is difficult.

  The object of the present invention is to solve the above-mentioned problems. In addition to the fact that the brightness of an image changes under transmitted light as in the case of an image formed using a conventional colored penetrating ink, the It is excellent in authenticity by disappearing as the same color as the color of the material, and can be manufactured by using commercially available ink without using special colored penetrating ink, under reflected light It is an object of the present invention to provide a forgery-proof printed matter characterized by high visibility of the image.

  The anti-counterfeit printed matter of the present invention is a first printing region having at least a part of a light-transmitting base material having the same hue as that of the base material under reflected light and a color having a lower brightness than the color of the base material. The first printing region is formed by laminating a penetrating image formed with ink containing a penetrating component and a color image formed with colored ink containing no penetrating component. The printed region is visually recognized by the difference in brightness with the base material under reflected light, and is not visible with the same color as the base material under transmitted light.

  Further, in the forgery-preventing printed matter of the present invention, the printed image is formed in a second color that is adjacent to the first printing area and is formed in the same color with the first printing area under reflected light by the ink that does not include the penetrating component. The first print area is the same color as the base material and is not visible under transmitted light, and the second print area is due to the difference in the amount of transmitted light between the base material and the second print area. Only visually recognized.

  In addition, the forgery-preventing printed material of the present invention is characterized in that the lightness L * of the first printing area is 70 or more and 90 or less.

  The printed image in the anti-counterfeit printed matter of the present invention is completely lost when watermarked. Unlike the determination of “quantity” such as shading, the determination of “presence / absence” that “image is present (not disappeared)” or “image is absent (disappeared)” requires a measuring instrument for everyone. It is a standard that can be determined without making it easy to explain. Therefore, even if the image is simply formed with one print pattern, it can be used as a criterion for authenticity determination by using “image presence / absence” under transmitted light as a reference.

  The printed image in the forgery-preventing printed material of the present invention does not require a structure surrounding the information portion representing significant information, unlike the background portion of Patent Document 2, and can form an image only with significant information to be expressed. For this reason, the visibility of the image under reflected light can be kept high.

  The printed image in the anti-counterfeit printed matter of the present invention is an image formed by a general printing method without using a special functional pigment. When constructing an image, there is no need for design restrictions, area ratio restrictions, substrate irregularities, etc., which are necessary for general anti-counterfeiting technology, and there is no sense of incongruity about gloss. Even if observed, it is indistinguishable from an image composed of normal ink. As described above, in spite of the anti-counterfeiting technology, the degree of freedom in design and the affinity with other designs are remarkably high, and it can be arranged in the security printed material without a sense of incongruity.

  The two inks needed to form the first printing area in the anti-counterfeit printed matter are generally commercially available, so there is no need to have a certain knowledge about the production of the ink, and the conventional special color penetration Manufacture is easier compared to anti-counterfeiting technology produced using mold ink.

  The anti-counterfeit printed matter formed by the above method cannot reproduce the effect even if the latest digital equipment is used, so it has an excellent anti-counterfeit effect and is the most productive offset printing method Cost performance is high.

The forgery prevention printed matter in this invention is shown. The structure of the 1st printing area | region in this invention is shown. The effect of the forgery prevention printed matter in this invention is shown. The component requirement of the 1st printing area | region in this invention is shown. The proper observation conditions of the forgery prevention printed matter in the present invention are shown. The forgery prevention printed matter of 2nd embodiment is shown. The structure of the print image of 2nd embodiment is shown. The effect of the forgery prevention printed matter of 2nd embodiment is shown.

  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.

(First embodiment)
In FIG. 1, the forgery prevention printed matter (1) in this invention is shown. The forgery-preventing printed matter (1) is formed by forming a printed image (3) having a color different from that of the substrate (2) on the substrate (2).

  The base material (2) which forms the forgery-preventing printed material (1) in the present invention needs to have a property of transmitting light like paper, so-called light transmission. Such a base material (2) includes fine paper and coated paper, but is not particularly limited as long as it is light-transmitting paper. In addition, there is no restriction | limiting in particular about the color of a base material (2).

  In the first embodiment, since only the first print area (10) is included in the print image (3), the print image (3) and the first print area (10) are the same. The print image (3) includes the first print region (10) having the same hue as that of the base material (2) and having a lightness lower than that of the base material (2). Further, the first print area (10) needs to be formed below a certain brightness, and details will be described later. In FIG. 1, the first print area (10) shows an example of “sakura petals”, but the image represented by the first print area (10) is not limited to this. Alternatively, it may be a mark or a character, or may be a multi-tone image having a plurality of tones.

  FIG. 2 shows the configuration of the first print area (10). The first printing area (10) is formed by superimposing a colored image (4) and a penetrating image (5). The colored image (4) is formed with a colored ink containing a coloring material such as a pigment or a dye, and the penetrating image (5) is formed with a penetrating ink containing a penetrating component. There is no particular restriction on the halftone dot area ratio in each image, and it is only necessary that the first print area (10) formed when the images are overlapped is formed with a certain lightness or less. However, in order to enhance the effect of disappearance of the image under the transmitted light of the present invention, it is desirable that the amount of transferred penetrating ink is large, so that the penetrating image (5) desirably has a high dot area ratio. . Further, since the color of the colored image (4) is basically the main component of the color of the first printing region (10), the colored image (4) has the same hue as the base material (2), And it needs to be a color whose brightness is lower than the color of the substrate (2).

  Here, the colored ink used for forming the colored image (4) and the penetrating ink used for forming the penetrating image (5) will be described. The colored penetrating ink used in the conventional invention such as Patent Document 2 is an image having a color that can be clearly seen under reflected light when printed on the substrate (2). On the other hand, it has the effect of changing the image extremely lightly under transmitted light. In other words, it is an ink having the effect of “the image looks lighter when seen through” as compared with a normal colored ink. Colored penetrating inks are composed of penetrating components and coloring materials, and the penetrating component suppresses the scattering of light inside the base material, resulting in the effect of making the image appear pale due to the increase in transmittance. Yes.

  In the present invention, instead of using the color penetrating ink in which the color material and penetrating component described in Patent Document 2 are mixed in one ink, the color ink containing the coloring material and the penetrating ink containing the penetrating component are overlapped. Form together. That is, it has a structure in which the function of a color material for visualizing an image under diffuse reflected light and the function of a penetrating component for erasing an image under transmitted light are secured by different inks. This achieves the same effect as the colored penetrating ink without using a special colored penetrating ink.

  The effect of the anti-counterfeit printed matter (1) of the present invention is shown in FIG. In the observation under reflected light as shown in FIG. 3A, the cherry blossom petals represented by the first print region (10) are visually recognized by the observer (7) with a certain contrast. On the other hand, in the observation under transmitted light as shown in FIG. 3B, the color of the cherry blossom petals is assimilated with the color of the base material (2), and the viewer (7) visually recognizes that the cherry blossom petals have disappeared. The

  The principle of the effect of the present invention will be described. In observation under reflected light, in addition to visually recognizing the color image (4) formed with the color ink containing the color material, the permeation image (5) superimposed on the color image (4) is oil-stained. Thus, it functions to slightly increase the reflection density of the first print area (10). From the above, the first print region (10) is visualized with a color obtained by subtractively mixing the color image (4) and the permeation image (5).

  On the other hand, under the transmitted light, the color itself of the first print area (10) does not change, but the lightness of the first print area (10) greatly increases due to the penetration component of the penetration image (5). The penetrating component contained in the penetrating ink is made of a resin close to the refractive index (1.49) of the cellulose fiber constituting the paper, and when printed on the base (2), the inside of the base (2) It fills the gap between the cellulose fibers and fills it with a penetrating component (resin). In this way, by forming a uniform space without a change in refractive index inside the paper, it becomes possible for light that has been refracted at the boundary between the cellulose fiber and the gap to travel straight ahead and transmit, As a result, the amount of transmitted light is increased, resulting in an effect that looks bright. On the other hand, the colored ink contains a color material. This color material functions to absorb light. As the light is absorbed, it cannot be transmitted through the paper. As a result, the amount of light that enters and passes through is reduced, resulting in the effect of appearing dark.

  Since the amount of light whose transmitted light amount is increased by the penetrating component and the amount of light whose transmitted light amount is decreased by the color material can be controlled to adjust the balance, the transmitted light amount that passes through the first printing region (10). And the amount of transmitted light passing through the substrate (2) can be made equal to the brightness of the substrate (2) and the printed image (3). In the conventional colored penetrating ink, since the hue of the substrate (2) and the hue of the printed image (3) are different, the printed image (3) is transferred to the substrate (2 by the difference in hue even if the lightness matches. ) And the like, and the effect that the image disappeared completely under transmitted light could not be obtained. In the present invention, the hue of the substrate (2) and the hue of the first printing region (10) are the same hue, so that the first printing region (10) and the substrate (2) under transmitted light. When the lightness of the ink is matched, the color becomes the same as that of the base material (2), and the first printing region (10) is visually lost. In the present invention, the disappearance effect of the first print area (10) is realized by the above principle.

  In addition, when the base material (2) is white, the colored ink has the same white hue as the base material (2) (in this specification, white and black achromatic colors are also considered as one hue). In addition, a color having a lightness lower than the color of the base material (2), that is, a gray color (black if the lightness is extremely lowered) may be used. In addition, the color of the first printing region (10) is not necessarily just lighter than the color of the base material (2), and it is necessary to adjust it to an appropriate lightness in accordance with the rate of increase in transmittance due to the penetrating component. There is. As an example, when the first printing region (10) is formed using a penetrating ink having a general performance in offset printing as the penetrating component, the lightness L * is 60 or less and the reflection density is 0.5 or more. Since the first print area (10) does not disappear completely under transmitted light, it is necessary to avoid the lightness below this. Desirably, the brightness L * is 70 or more and the reflection density is 0.3 or less. In addition, if the image is too light, an image that is visible under reflected light cannot be formed. Therefore, it is necessary to set the lightness L * 95 or less and the reflection density to 0.05 or more, and desirably the lightness L * is 90 or less and the reflection density is 0. .1 or more is good.

  In addition, the color of the first print area (10) is not determined only by the color of the color image (4) formed with the color ink containing the color material, and the color of the penetration image (5) is also taken into consideration. There is a need. The penetrating ink itself is basically colorless and transparent, but when printed, the penetrating component in the ink penetrates the base material (2) to form an oil stain with a darker base material (2). Is done. Although this oil stain has a light color, it has a visible color difference as compared with the base material (2), and thus has a visible effect on the color of the first printing region (10). . Specifically, by superimposing the colored image (4) and the penetrating image (5), the brightness is slightly lower than the color of the colored image (4) alone. For this reason, when the color of the first print area (10) is strictly set, the color obtained by subtractively subtracting the color of the colored image (4) and the color of the penetration image (5) is always used as a base. Need to think about. If it is desired to design the first print area (10) with a reflection density of 0.15, the color density of the colored image (4) is 0 if the reflection density of the penetrating image (5) reaches about 0.02. It is necessary to design a color that stops at .13.

  Here, a specific definition of the first print area (10) will be described. As shown in FIG. 4, the image (4A) formed with the colored ink and the image (5A) formed with the penetrating ink are images of completely different shapes, and the two images partially overlap each other. If so, the area where the two images overlap can be considered as the first print area (10). Of the image (4A) formed with colored ink, the image forming the first printing area (10) is defined as a colored image (4), and the image (5A) formed with penetrating ink is used. Of these, the image forming the first print area (10) is referred to as a penetration image (5). Note that the image (4A) and the image (5A) that are not overlapped are regarded as a modification portion adjacent to the first print area (10). In addition, as a matter of course, the first printing region (10) has the same hue as the base material (2) and a lightness lower than that of the base material (2), and is invisible under transmitted light. It is necessary to satisfy the effect of becoming.

  Note that the effect of disappearance of the first print region (10) depends on the state of light in the observation environment because transmitted light is used. As a matter of course, the disappearance effect increases when strong light is used as transmitted light, but the disappearance effect decreases when the light is weak. In addition, when the surface on which the printed image (3) is formed on the base material (2) is the front side and the opposite side is the back side, the disappearance effect of the first printing region (10) is transmitted light from the back side of the printed matter. It is not only affected by the intensity of the incident light, but also affected by the intensity of the light incident on the printed surface. In order to explain each influence concretely, the figure which observes the forgery prevention printed matter (1) of this invention in a specific environment in FIG. 5 is shown.

  FIG. 5 is a diagram in which the effect of the anti-counterfeit printed matter (1) of the present invention is visually recognized using the light table (9) in an environment according to an actual office. If the lightness L * of the first printing region (10) in the forgery-preventing printed matter (1) is about 85 to 80, the first printing region (10) of the present invention is counterfeited from the light source (6R). If the light (8R) incident on the front side of the prevention printed matter (1) is in a dim environment with an illuminance of 10 lx or less, the transmitted light (8T) at the table top of the light source (6T) of the light table (9) has an illuminance of 1000 lx or more. If there is, disappearance effect will occur. In an environment where the light incident on the front side (8R) according to the brightness on a normal office desk has an illuminance of about 300 lx, the illuminance of 2000 lx or more in the transmitted light (8T) is required to completely erase the image. Is required. In a very bright environment where the light incident on the front side (8R) exceeds an illuminance of 600 lx, the transmitted light (8T) needs an illuminance of 3500 lx or more to completely erase the image. As described above, the illuminance of the transmitted light (8T) necessary for erasing the image changes according to the illuminance of the light (8R) incident on the front side. Basically, when light having an illuminance of 3500 lx or more is used as transmitted light, it is possible to reliably determine authenticity in an environment according to a general office.

  The illuminance of 3500 lx is a general value as the illuminance at the table top of a commercially available light table, and by using such a light table, it is possible to reliably determine authenticity. In addition, this level of illuminance is obtained at a distance of about 20 to 30 cm from a general fluorescent lamp in an office, and a method of bringing the anti-counterfeit printed matter (1) close to this distance against the fluorescence of the ceiling, etc. It may be used to determine authenticity. If the ceiling is high and the distance to the fluorescent lamp is long, it is difficult to bring the anti-counterfeit printed matter (1) close to the desk. Prepare a general desk light on the desk and bring the anti-counterfeit printed matter (1) close to it. With this, authenticity can be reliably determined.

  If the above-described conditions cannot be satisfied, the lightness of the first print area (10) may be designed to be slightly high (reflection density is low). In addition, since the brightness level of the first print area (10) is in proportion to the disappearance effect, it disappears by increasing the brightness of the first print area (10) even in an environment without sufficient illuminance. An effect can be obtained. For example, even if the first print area (10) formed at a brightness of about 85 under a certain illumination environment does not disappear under transmitted light, if the brightness of the first print area (10) is increased to a brightness of about 90, it is almost In this case, the first print area (10) can be lost under transmitted light.

  “Observation under reflected light” in the present invention refers to a situation where the observer's viewpoint is in an area where there is almost no specular reflection light and the anti-counterfeit printed matter (1) is observed under visible light. In the present invention, “observation under transmitted light” indicates a situation in which the observer's viewpoint is in the area under transmitted light and the anti-counterfeit printed matter (1) is being observed.

  In addition, the lightness in this specification refers to the brightness of a color, and when it is high, it is bright, and when it is low, it is dark. Saturation refers to the degree of color vividness. In addition, “color” in the present invention represents a color including the concept of hue, saturation, and lightness, and “hue” refers to a color aspect such as red, blue, and yellow. Specifically, the intensity distribution of a specific wavelength in the visible light region (400 to 700 nm) is shown. In this specification, white and black are also regarded as one hue. The “same hue” in the present invention means that the colors of red, blue, and yellow are the same in the two colors, and the distribution of the intensity of the wavelength in the visible light region has a correlation in the two colors. For this reason, in this specification, even if it is an achromatic color such as white, gray, and black, there is a correlation in the intensity distribution of the wavelength in the visible light region, and therefore the same hue.

  The penetrating component in the present invention refers to a component that functions to increase the transmittance of the printing region by penetrating into the paper during printing. Specifically, the refractive index of cellulose (1.49) Refers to resin, wax, animal and vegetable oils, etc.

  Further, the “penetrating ink” in the present invention refers to an ink that contains the aforementioned penetrating component and is generally sold as a watermark ink. Examples of such ink include T & K TOKA's best one watermark ink, T & K TOKA's UV watermark ink, Teiko Ink unimark, Toyo Ink SMX watermark ink, Joint ink E2 varnish, and the like. Moreover, if it is transparent and has a low viscosity, even an ink similar to a general gloss varnish or overprint varnish has a certain watermark effect and can be used as a penetrating ink.

  In addition, for the purpose of determining the occurrence of reprinting and printing defects in penetrating inks or for the purpose of improving authenticity discrimination, luminescent pigments and luminescent dyes such as fluorescent pigments, fluorescent dyes, phosphorescent pigments and phosphorescent pigments Even if functional materials such as an infrared absorbing material and an infrared reflecting material are added, there is no problem.

  The printing method of the printed image (3) formed on the anti-counterfeit printed matter (1) of the present invention is not particularly limited, and offset printing, flexographic printing, gravure printing, intaglio printing, screen printing, or the like may be used. it can.

  In the first embodiment, the print image (3) is composed of only the first print area (10). However, the authenticity determination can be made by combining the first print area (10) and another image element. The anti-counterfeit printed matter (1) with improved properties and visibility may be formed. The specific method will be described below as a second embodiment.

(Second embodiment)
FIG. 6 shows an anti-counterfeit printed matter (1 ′) according to the second embodiment. The forgery-preventing printed matter (1 ′) is formed by forming a printed image (3 ′) having a color different from that of the base material (2 ′) on the base material (2 ′).

  FIG. 7 shows an outline of the configuration of the print image (3 ′). The print image (3 ′) in the second embodiment includes the first print area (10 ′) having the disappearance effect and the second print area (10 ′) having no disappearance effect adjacent to the first print area (10 ′). It has a print area (11 '). As long as the second printing region (11 ′) is an image formed without containing penetrating ink, there are no restrictions on the constituent materials and the forming method. The two images are not particularly limited as long as they are adjacent to each other, but if the colors of the two images are the same color, or if the two images are combined to represent significant information, This is desirable because the effect when observed under transmitted light can be easily discriminated and the authenticity is improved. In addition, although the 1st printing area | region (10 ') and 2nd printing area | region (11') which comprise the printing image (3 ') shown in FIG. 7 are not in the adjacent state, as shown in FIG. In the present specification, it is assumed that an image of two regions is included in the adjacent concept as long as the image represents one piece of significant information in close proximity. Here, as an example of the second embodiment, the two images of the first print area (10 ′) and the second print area (11 ′) constituting the print image (3 ′) have the same color. In addition, an example in which two images are combined to represent information on cherry blossom petals will be described.

  The print image (3 ′) is composed of a color image (4 ′) formed with a color ink containing a color material, a color composite image (12 ′) having a second print area (11 ′), and a penetrating ink. It is formed by superimposing the formed penetration images (5 ′). The colored image (4 ′) and the penetrating image (5 ′) have the same shape. In constructing the print image (3 ′), the color image (4 ′) and the penetrating image (5 ′) are printed in a positional relationship.

  The two images of the first print area (10 ') and the second print area (11') in the print image (3 ') are in the same color relationship, but the color image in the color composite image (12') The color of (4 ′) is slightly different from the color of the second print area (11 ′). Specifically, it is necessary to design the color of the colored image (4 ′) slightly higher in brightness than the color of the second print area (11 ′). This is because, as described in paragraph (0034), the permeation image (5 ′) is also visualized as an image having a certain density, and the brightness decreases when the permeation image (5 ′) is overlaid. This is because it is necessary to design the color of the colored image (4 ′) in advance.

  FIG. 8 shows the effect of the anti-counterfeit printed matter (1 ′). As shown in FIG. 8 (a), when the anti-counterfeit printed matter (1 ′) is observed under reflected light, the petal of cherry blossoms composed of a first printing area (10 ′) and a second printing area (11 ′). A printed image (3 ′) representing the image is visually recognized. On the other hand, as shown in FIG. 8B, when the anti-counterfeit printed matter (1 ′) is observed under transmitted light, the first region (10 ′) of the printed image (3 ′) is the base material (2 ′). ), And the color is completely disappeared and only the second print area (11 ′) having no disappearance effect is visually recognized. As described above, the anti-counterfeit printed matter (1 ′) according to the second embodiment is characterized in that the pattern visually recognized by the reflected light and the transmission effect is changed.

  The reason for forming the print image (3 ′) by combining the first print area (10 ′) and the second print area (11 ′) is as follows. Although the first printing region (10 ′) has an excellent disappearance effect, the effect changes depending on the amount of light in the observation environment as described above. That is, when there is direct sunlight having an illuminance suitable for the observation environment, a light source such as a fluorescent lamp or a light table in a general office, the first printing region (10 ' ) Disappears completely, but only indirect lighting, and in a dark room where adequate illuminance cannot be ensured, although it varies slightly depending on its density, it may not disappear completely. In order to cope with the case where the effect is influenced by the illumination conditions of the observation environment in this way, by arranging the second print area (11 ′) paired with the first print area (10 ′) in the vicinity. The effect can be relativized. As a result, even if the first print area (10 ′) does not completely disappear in a dark room with only indirect illumination, the color changes to a lighter color than the second print area (11 ′). By confirming the above, it is possible to make a reliable authenticity determination. As described above, the first print region (10 ′) can be used as a part of the pair image as in the conventional technique. Further, even in the case of such a printed image (3 ′), the effect that the image changes lightly is higher than that of the printed image (3 ′) formed using the conventional color penetrating ink. Since the effects can be visualized more relativistically, the authenticity discrimination ability is higher than that of the conventional type printed image (3 ′).

  The second embodiment is an example in which the colored image (4 ′) and the second print area (11 ′) are formed with the same ink from the viewpoint of improving productivity. On the other hand, the colored image (4 ′) and the second print area (11 ′) may be formed with different inks. In this case, if the second print area (11 ′) has a particularly low light-transmitting characteristic, the contrast between the first print area (10 ′) and the second print area (11 ′) at the time of transmission. And the disappearance effect of the first print area (10 ′) is relatively emphasized, which is more desirable.

  As a material that can reduce the light transmittance of the image, specifically, an ink containing a metal pigment with high light blocking properties such as titanium dioxide, iron oxide, zinc oxide, aluminum oxide, An ink containing silicon dioxide, calcium carbonate, or the like can also be used. Or you may make light transmittance low by printing with a thick film thickness using the general ink which does not contain a special metal pigment.

  Only the form which forms two images of the 1st printing field (10 ') and the 2nd printing field (11') on the one side surface of a substrate (2 ') like the example of a 2nd embodiment. Instead, the first printing region (10 ') is formed on the surface of the base material (2'), and the first printing region (10 ') on the back surface of the base material (2') is sandwiched at the same position. If the second print area (11 ′) is formed, only the first print area (10 ′) can be seen under reflected light, and only the second print area (11 ′) present on the back surface can be seen under transmitted light. It is possible to adopt a form having a so-called image change effect. In this case, if the second print area (11 ′) is the same color as the base material (2 ′), the presence of the second print area (11 ′) is not known when observed from the back side, and it is more desirable because it functions as a latent image. .

  As described above, the configuration of the anti-counterfeit printed material including the printed image according to the present invention can take various forms. Hereinafter, examples of a printed matter provided with a specifically produced print image will be described in detail in accordance with the above-described embodiment for carrying out the invention, but the present invention is not limited to this example.

  The present example is an anti-counterfeit printed matter (1 ′) having the form described in the second embodiment, and will be described with reference to FIGS. FIG. 6 shows an anti-counterfeit printed matter (1 ′) in the example. The anti-counterfeit printed matter (1 ′) is formed by forming a gray printed image (3 ′) on a white substrate (2 ′). For the base material (2 ′), general white fine paper (Shiraoi Nippon Paper Industries Co., Ltd.) was used.

  As shown in FIG. 7, the print image (3 ′) has the same color as the first print area (10 ′) and the first print area (10 ′) which are formed of colored ink and penetrating ink. It consists of a second print area (11 ') with a gray color. This print image (3 ′) is composed of an overlay of a colored composite image (12 ′) and a penetration image (5 ′). The color composite image (12 ′) is composed of a color image (4 ′) and a second print area (11 ′). The color image (4 ′) has a halftone dot area ratio of 10%, and the second print area (11 ′) Is a dot area ratio of 20%. In order to form this colored composite image (12 ′), black ink (Best One Perfect Black M-HS manufactured by T & K TOKA) was printed by a wet offset printing method. Also, the penetrating image (5 ′) has a halftone dot area ratio of 100%, and the same wet offset printing method is used so that it overlaps the colored image (4 ′) using penetrating ink (made by T & K TOKA Co., Ltd.). Printed. As a result, the reflection density of the black component in the first print area (10 ′) is 0.16, the lightness L * is 80, and the reflection density of the black component in the second print area (11 ′) is also 0.16. The lightness L * was also 80.

  The effect of the anti-counterfeit printed matter (1 ′) produced with the above configuration will be described below with reference to FIG. In this embodiment, in a general office environment with an illuminance of about 300 lx, where there are two 40 W general fluorescent lamps on the ceiling directly above about 1 m, an anti-counterfeit printed matter is placed on a light table with an illuminance of about 3500 lx on the table top. (1 ') was arranged and observed. As shown in FIG. 8 (a), when the anti-counterfeit printed matter (1 ′) is observed under reflected light, a gray print consisting of a first print region (10 ′) and a second print region (11 ′) A printed image (3 ') representing the cherry blossom petals was visible. On the other hand, as shown in FIG. 8B, when the anti-counterfeit printed matter (1 ′) is observed under transmitted light, the first printing region (10 ′) of the printed image (3 ′) is the base material (2 ') And the color disappeared completely and only the second print area (11') was visually recognized as dark gray. As described above, it was confirmed that the anti-counterfeit printed matter (1 ′) of the present invention changes the pattern visually recognized under reflected light and through the transmission effect.

1, 1 ′ anti-counterfeit printed matter 2, 2 ′ base material 3, 3 ′ printed image 4, 4 ′ colored image 4A image formed with colored ink 5, 5 ′ penetrating image 5A image formed with penetrating ink 6R, 6R 'light source 6T, 6T' light table light source 7 'observer's viewpoint 8R light incident on the front side 8T transmitted light 9 light table 10, 10' first print area 11 'second print area 12' colored composite image

Claims (3)

A printed image having a first printing region having a color having the same hue as that of the base material under reflected light and a color having a lightness lower than the color of the base material on at least a part of the base material having light transmittance. The first printing area is formed by laminating a penetrating image formed with an ink containing a penetrating component and a colored image formed with a colored ink not containing the penetrating component. The forgery-preventing printed matter, which is visually recognized by a difference in brightness from the base material under reflected light and cannot be visually recognized in the same color as the base material under transmitted light. The printed image has a second print area that is adjacent to the first print area and is formed in the same color as the first print area under reflected light by the ink that does not include the penetrating component. Under the transmitted light, the first print area is not visible because it is the same color as the base material, and only the second print area is due to the difference in the amount of transmitted light between the base material and the second print area. The anti-counterfeit printed matter according to claim 1, which is visually recognized. The forgery-preventing printed matter according to claim 1 or 2, wherein the lightness L * of the first printing region is 70 or more and 90 or less.

Images