JP2017065185A - Forgery preventive printed matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a forgery preventive printed matter employing such technology that different images appear under diffused reflection light and specular reflection light, in which visibility of images under both of the reflection light is improved.SOLUTION: The forgery printed matter includes layers of a first image formed of a colored ink having a hue different from that of a substrate and a second image formed of a brilliant ink having the same hue as that of the colored ink. On a basis of gradations of first significant information appearing under diffused reflection light and of second significant information appearing under specular reflection light, the first image is divided into first significant information and second significant information by differentiating densities while gradations are not reversed; and the second image is divided by differentiating densities into first significant information where the gradation is not reversed and second significant information where the gradation is reversed. The first significant information and the second significant information are formed with identical shapes, sizes and locations.SELECTED DRAWING: Figure 2

Description

  In the field of security printed matter such as banknotes, passports, securities, identification cards, cards, and passports that require an anti-counterfeit effect, the present invention provides images that can be observed depending on the angle of incident light. This is related to anti-counterfeit printed matter that changes.

  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. As one of the anti-counterfeiting techniques for preventing such duplication and counterfeiting, there are many ones to which an optical security element typified by a hologram that changes an image depending on a printed matter or an observation angle has been attached.

  However, unlike conventional anti-counterfeiting technology, which is formed by printing with ink, holograms are formed using complex manufacturing processes and special materials, making them more difficult to manufacture compared to conventional anti-counterfeit prints. It is time consuming and extremely expensive. Therefore, special light-reflecting powders such as metal ink, interference mica, oxidized flake mica, pigment-coated aluminum flakes, and optically changing flakes are blended in inks and paints, By using a complicated halftone dot configuration, a forgery-preventing printed matter that can be formed by a general printing method, which realizes an image change similar to a hologram, has appeared.

  While the applicant uses general and relatively inexpensive materials and simple printing means, the information recognized by the human eye at a specific part in the printed material at a specific observation angle is the observation angle. An invention relating to an information carrier for preventing counterfeiting that changes to completely different information by changing the value of the information has already been filed (see, for example, Patent Document 1, Patent Document 2, Patent Document 3, and Patent Document 4).

Japanese Patent No. 3398758 Japanese Patent No. 4604209 Japanese Patent No. 5358819 Japanese Patent No. 5245102

  In the techniques described in Patent Document 1 to Patent Document 4, an image that has been viewed under diffuse reflection light disappears under specular reflection light, and at the same time, an image that is completely different from the image that has been viewed until then appears. This is a technology that excels in the so-called image change effect. The effect of disappearing the image viewed under diffuse reflected light is that the image formed with glittering ink is specularly reflected and the brightness increases and the whole image becomes pale, and the gradation of the entire image is compressed. This is caused by the fact that it cannot be caught visually. However, when it is formed on a substrate having high smoothness such as coated paper or art paper, the image that has been visually recognized under diffuse reflection light may not be completely lost.

  The above problem will be described in detail with reference to FIG. In the printed matter shown in FIG. 11, the letter “A” of the alphabet is visually recognized under diffuse reflection as shown in FIG. 5, and the letter “B” of the alphabet appears under regular reflection. Assume that the designed information carrier for preventing counterfeiting is described in Patent Documents 1 to 4. In this case, when a general fine paper or fine coated paper is used as a base material, if the design is appropriate, as shown in FIG. 11A, the alphabet “ The letter “A” disappears completely under specular reflection, and only the letter “B” of the alphabet is visible.

  On the other hand, when the anti-counterfeit information carrier described in Patent Documents 1 to 4 is formed using a highly smooth paper such as coated paper or art paper as a base material, even if the design is appropriate, FIG. As shown in (b), the letter “A” of the alphabet that was visually recognized under diffuse reflected light does not disappear even under regular reflected light, and the gradation under diffuse reflected light is negative-positive inverted. (In this example, a negative state), it may appear overlapping the letter “B” of the alphabet. Specifically, in an area other than the image that appears under specular reflection light, that is, in an area other than the letter “B” of the alphabet, an image that has been viewed under diffuse reflection light, that is, the letter “A” of the alphabet Appears to be negative-positive reversed.

  This is because papers with high smoothness such as coated paper and art paper generally have high glossiness, and the amount of light reflected from the image formed with glittering ink is added to the reflected light from the substrate. And is significantly larger than the case of using high-quality paper as a base material. This phenomenon of increasing the amount of reflected light itself is desirable because it greatly contributes to the image disappearance effect. However, since paper with high smoothness has a flat substrate surface, the image formed with glittering ink is also flattened. As a result, reflected light generated from the image does not spread widely. , Sharply extend to a limited angle range. For this reason, the strong reflected light of the area formed with high dot area ratio by the glitter ink and the weak reflected light amount of the area formed with low dot area ratio are respectively in the space where the observer's viewpoint exists. As a result, it is considered that the gradation of the image visually recognized under the diffuse reflected light does not completely disappear.

  Note that the gradation of the image viewed under diffuse reflected light becomes negative / positive inversion under regular reflected light because the amount of reflected light in areas with high area ratios (dark areas) increases. This is because the amount of reflected light in a region where the area ratio is low (light-colored region) is reduced, the brightness is lowered, and the density is inverted.

  On the other hand, when high-quality paper or the like is used as a base material, the surface of the base material is not flat and is disturbed by fine irregularities, so reflected light generated from the image tends to spread widely over a wider range, and as a result is strong It is thought that the mixed tone of reflected light and weak reflected light increases the tendency of the gradation of the image viewed under diffuse reflected light to disappear (however, in the case of fine paper, the base material surface is large) Because it is distorted, the amount of reflected light generated from an image formed with glittering ink is also suppressed to be lower than that of coated paper, so that the visibility of an image appearing under regular reflected light is reduced.

  As mentioned above, it is actually possible to print more delicately by using a substrate with high smoothness such as coated paper or art paper than paper with low smoothness such as fine paper. The latent image also has high visibility and excellent gradation expression, so the total performance is much higher, but the image that was visible under diffuse reflection as described above does not disappear completely There is a problem when using a base material with high smoothness in one point that it may appear in a negative-positive inverted state.

  Furthermore, regarding the technique of Patent Document 1, the luster material constituting the first print image and the color material constituting the second print image are different in hue, so that they are originally visually recognized in the observation under diffuse reflected light. There is a problem in that the second print image that cannot be seen is visible, and the second print image is configured with a sparse area ratio, so the visibility of the second print image that appears under specular reflection light is low. There was a problem of being low.

  The techniques described in Patent Document 2 and Patent Document 3 are techniques for forming an anti-counterfeit printed material by superimposing a glittering material and transparent ink. Unlike the technique of Patent Document 1 using a color material for forming a latent image. However, since the ink for forming the latent image is transparent, there is no need for color adjustment in the first place, and the latent image is not visualized under diffuse reflected light, and the technology has excellent image switchability. Since transparent ink that cannot be visually observed is used, there has been a problem that it is difficult to control print quality during production.

  As a countermeasure for this, use transparent light-emitting ink that is a mixture of transparent ink and UV-excited light-emitting pigment, and irradiate UV light during printing to determine whether the transparent ink is printed without problems. Was common. However, when such measures are used, quality control at the time of manufacture is possible, but the structure of the latent image can be easily grasped by looking at the luminescent image that appears during UV irradiation. May give a clue to the structure of anti-counterfeiting technology, and there has been a problem regarding resistance to forgery.

  Furthermore, the technique described in Patent Document 4 is configured such that two images are formed using a glittering material and a colored ink having the same color as the glittering material as a pair ink, and the optical properties of the two equal color inks under specular reflection light. It is a technology that realizes the effect of changing the image by utilizing the difference in characteristics, but each image composed of two inks fits so that they do not overlap each other, and is printed with the highest degree of difficulty called “tweeping” When alignment is required and even a slight misalignment occurs, the latent image is visualized. Although the anti-counterfeiting effect was very high, there was a problem that a high-precision printing machine and a skilled operator were necessary for the production.

  The present invention aims to solve the above-described problems, and forms a colored ink and a glittering ink having the same hue as the colored ink as a pair ink, and the image changes under diffuse reflected light and regular reflected light. Even if the printed image has an effect, and the gradation expression range of the image that can be observed under diffuse reflected light is designed to be wide, the brightness is not increased and the image that can be observed under regular reflected light is not affected. To provide anti-counterfeit printed matter having a high image change effect.

  The present invention comprises, on at least a part of a substrate, a printed image that exhibits first significant information under diffusely reflected light and second significant information under specularly reflected light. The first significant information that appears under diffuse reflection, consisting of a first image formed with colored inks with different colors and a second image formed with glitter ink with the same hue as the colored ink When the gradation of the second significant information that appears under regular reflection light is used as a reference, the first image is the first significant information in a state where each gradation is not inverted by making the shades different. The second image is classified into the second significant information, and the second image has different gray levels so that the first significant information in the state where the gradation is not reversed and the second significant information in the state where the gradation is reversed. Divided into information, the first of each of the first image and the second image Significant information and second significant information are formed in the same shape, size, and arrangement position, the first significant information can be visually recognized under diffuse reflected light, and the first significant information disappears under regular reflected light. Thus, the anti-counterfeit printed matter is characterized in that only the second significant information can be visually recognized.

  The printed image of the anti-counterfeit printed matter of the present invention is a third image laminated between the first image and the second image with an ink having at least one of light / dark flip-flop property and color flip-flop property. The third image is divided into a pattern part and a background part by arranging the raised convex lines in a line, and the arrangement direction of a part of the line-shaped convex lines is different. The third significant information is formed, and the third significant information can be further visually recognized in a region where diffuse reflection light and regular reflection light are mixed.

  Furthermore, the forgery-preventing printed matter of the present invention is characterized in that the difference between the maximum and minimum halftone dot area ratios of the second image exceeds 50%.

  The anti-counterfeit printed matter of the present invention is designed so that the brightness of the first significant information that can be observed under diffuse reflected light is designed to be wide, and the lightness does not increase excessively even in dark areas. Since the second significant information that can be observed is not affected, the image change effect is high.

  In the observation under diffuse reflected light as in Patent Document 1, the second printed image (second significant information referred to in the present invention) that should not be visually recognized is not visually recognized. In addition, since the transparent ink as in the prior art described in Patent Document 2 and Patent Document 3 is not used, there is no need to emit and manage the latent image as in the prior art, and the image formed by the colored ink is not necessary. Quality should be controlled visually. Therefore, when a print image is formed by overlapping two images, it is difficult to see the configuration, and the resistance to forgery is high.

  The two images constituting the forgery-preventing printed material according to the present invention have a fixed positional relationship of overlapping portions, and therefore basically require a certain printing accuracy. However, since there is no problem if the inks that make up each other overlap, the redundancy of printing is increased by thickening the outline of the image and slightly overlapping the two images, as in normal printing operations. Can be secured. Therefore, unlike the prior art described in Patent Document 4, it is not necessary to fit the images together by complete tweezers, and since high printing accuracy is not required, manufacturing is easy.

  The anti-counterfeit printed matter formed by the above method is excellent in cost performance because it can be manufactured by offset printing, which is a highly productive printing method, and even if the latest digital equipment is used, it is possible to realize the switch effect Since it is impossible, it has an excellent anti-counterfeit effect.

The forgery prevention printed matter in this invention is shown. The outline | summary of a structure of the forgery prevention printed matter in this invention is shown. FIG. 3 shows a schematic diagram of a second image density calculation method according to the present invention. The layer structure of the forgery prevention printed matter in this invention is shown. The effect of the forgery prevention printed matter in this invention is shown. The forgery prevention printed matter in this invention is shown. The outline | summary of a structure of the forgery prevention printed matter in this invention is shown. The structure of the 3rd image in this invention is shown. The layer structure of the forgery prevention printed matter in this invention is shown. The effect of the forgery prevention printed matter in this invention is shown. The effect in a prior art 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)

  First, the present invention will be described with reference to the drawings. In FIG. 1, the forgery prevention printed matter (1) in this invention is shown. The anti-counterfeit printed matter (1) has a printed image (3) having a color different from that of the base material (2) on the base material (2). The image shown in FIG. 1 (a) is an image that can be seen in the printed image (3) under diffuse reflected light, and the image shown in FIG. 1 (b) is a printed image at an observation angle where specularly reflected light is dominant. It is an image visible in (3). As shown in FIG. 1A, the printed image (3) shows the first significant information (9) under diffuse reflected light. The first significant information (9) in the present embodiment is the letter “A” in the positive alphabet in which the character portion appears darker than the surroundings.

  As shown in FIG. 1B, the printed image (3) shows the second significant information (10) at the observation angle where the regular reflection light is dominant. In the present embodiment, the second significant information (10) is the letter “B” in the positive alphabet in which the character portion appears darker than the surroundings. The significant information referred to in the present invention is not limited to the aforementioned alphabet, and is not particularly limited as long as it can be recognized as information such as characters, symbols, and patterns.

  The print image (3) is formed by combining two images as shown in FIG. The two images are the first image (4) and the second image (5). First, the first image (4) will be described.

  In the first embodiment, the first image (4) includes first significant information (9) and second significant information (10) in a state where the gradation is not inverted. In the present embodiment, the first significant information (9) is the letter “A” in the positive state, and the second significant information (10) is the letter “B” in the positive state. The first significant information (9) and the second significant information (10) in the first image (4) are in a state where the gradation is not inverted, that is, in the positive state alphabets “A” and “B” "Is included. In this specification, “the state where the gradation is inverted” and “the state where the gradation is not inverted” are the first significant information (9) visually recognized under diffuse reflected light. The gradation of the second significant information (10) visually recognized under reflected light is defined as a reference. That is, in the present invention in which the first significant information (9) visually recognized under diffuse reflected light is in a positive state, the negative state is referred to as “a state where the gradation is reversed”, and the positive state is referred to as “positive state”. It is defined as “a state in which the gradation is not inverted”. The same applies to the second significant information (10).

  First, the shade design of the print image (3) will be described. If the design value of the difference in shading in the printed image (3) is large, the visibility of the first significant information (9) under the diffuse reflected light is improved, but conversely the specularly reflected light is dominant at the observation angle. One significant information (9) may not be completely lost. For this reason, it is necessary to provide a certain restriction on the density difference in the printed image (3). This is unclear because it is affected by the performance of the glitter ink used in the second image (5), but the difference in density (the difference between the maximum reflection density and the minimum reflection density) in the printed image (3). ) Exceeds 1.0 in the reflection density of the main color component, the first significant information (9) may be lost under specular reflection light, no matter how bright ink having excellent optical characteristics is used. Disappear. From the above, the density difference in the printed image (3) needs to be 1.0 or less in terms of reflection density. When the difference in shading is 1.0 or less in the reflection density, the remarkable effect was found to be 0.75 or less from the results of a plurality of levels. Similarly, since the disappearance effect of the first significant information (9) at the observation angle where the specular reflection light is dominant is dramatically reduced, the substrate (2) is visually observed in the printed image (3). It is necessary to avoid providing a completely exposed area as large as possible. The above is the outline of the configuration of the print image.

  Next, the configuration of the first image (4) will be described. In the first image (4), there are positive letters “A” and “B”, but in a region where “A” and “B” overlap, the second significant information ( 10), and the density of the letter “B”. That is, in the first image (4), the letter “A” as the first significant information (9) is only in an area where the letter “B” as the second significant information (10) does not exist. Be placed.

  The shading of the first image (4) will be described. First, since the first image (4) needs to be completely hidden in the shade of the print image (3), the maximum reflection density of the first image (4) is the print image (3). It is necessary to make it below the minimum reflection density. Further, the density of the first significant information (9) in the first image (4) is lower than the density of the second significant information (10) in the first image (4), and The density needs to be lower than the density of the first significant information (9) in the second image (5). When the density of the first significant information (9) in the first image (4) is higher than the above-mentioned restriction, the gradation of the first significant information (9) is not inverted under specular reflection light. It must be avoided because it is visualized in a state and is viewed at the same time as the first significant information (9).

  In the example of the first embodiment, in the first image (4), the background areas other than the letters “A” and “B” in the alphabet are formed as white areas with zero density. The configuration of the first image (4) is not limited to this, and the background may have a certain density. When a constant density is given to the background, the visibility of the second significant information (10) under specular reflection light is slightly reduced, but most of the printed image (3) is overlapped by two inks. Therefore, even if there is a problem in the color matching properties of the two inks used, the color matching properties can be improved by superimposing the inks in the printed image (3). That is, it can be said that the configuration in which a constant density is given also to the background of the first image (4) is a form in which the effect is slightly reduced and the manufacturability is improved. However, even when a certain density is applied to the background of the first image (4), if the density of the letters “A” and “B” in the alphabet is exceeded, the first significant information (9) and Since the second significant information (10) and the negative / positive are reversed, it is necessary to stop at a density at which the negative / positive is not reversed even when the density is applied to the background.

  In the present specification, the term “positive” means that, in the example in which characters and patterns exist separately from the background, as in the example of the first embodiment, the characters and patterns are dark, In the example where characters and patterns exist separately from the background, `` negative '' means a light and dark composition with a light background and a dark background. Point to.

  Also, unlike the case where characters, patterns, etc. exist separately from the background, in the case of a configuration where the entire image has gradation like a landscape photo, “positive” means the original scenery taken In the same state as the light and shade, the composition of light and shade is shown, and “negative” means the composition of light and shade in the state where the light and shade of the original landscape is inverted.

  In the first image (4), in order to form the first significant information (9) and the second significant information (10), the first image (4) is divided by making the shades different. Note that the method of varying the shade can be achieved by a known technique, for example, by varying the dot area ratio, the printed film thickness, or using a color material having a different shade. .

  The first image (4) is formed with a colored ink having a color different from that of the substrate other than the transparent substrate. The color of the first image (4) can be any color. This colored ink needs to have a difference in reflectance under the specular reflection light from the glitter ink used in the formation of the second image (5). This is an indispensable requirement for causing the second significant information (10) to appear under regular reflection light and for improving its visibility. Since the glitter ink is basically a highly reflective ink, it is desirable that the colored ink for forming the first image (4) should have a lower reflectance than the glitter ink. The visibility of the second significant information (10) is enhanced. It can be said that the mat is desirable as much as possible.

  The first image (4) may be formed by any printing method such as offset printing, flexographic printing, relief printing, gravure printing, intaglio printing, or screen printing. The above is the description of the first image (4).

  Next, the second image (5) will be described. The second image (5) includes first significant information (9) in a state where the gradation is not inverted and second significant information (10) in a state where the gradation is inverted. That is, the example of the first embodiment includes a letter “A” in the positive state and a letter “B” in the negative state. The shade design of the second image (5) is slightly more complicated than the first image (4), and the density of each region is the same as that of the first image (4) from the density of the printed image (3). It is constructed by subtracting the density of the area. The final method of specific concentration will be described later.

  In the present specification, “light / dark” means that a specific color is distributed at various color densities (reflection densities) in an arbitrary image, and is synonymous with gradation. When expressing the color density of a specific point of the image, it is simply described as color density, density, or reflection density.

  The second image (5) needs to be formed with a glittering ink having the same hue as the colored ink used in the formation of the first image (4). This is because when the printed image (3) is finally formed, the first image (4) and the second image (5) and the respective second significant information (10) are fitted together, The first significant information (9) overlaps and the two images are combined, so that the second significant information (10) becomes invisible and concealed under diffuse reflected light. For this purpose, in a state where the first image (4) and the second image (5) are combined, it is necessary that the respective predetermined regions have the same color.

  Of these colors, the brightness can be controlled by adjusting the halftone dot area ratio at the time of plate design and the ink film thickness at the time of printing, but at least the two inks are the same at the ink design stage. If it does not have a hue, it is impossible to have the same color when the two images are fitted together. For this reason, it is necessary to have the same hue as the colored ink that forms the first image (6) and the glitter ink used in the formation of the second image (5).

  In the present invention, “the first image (4) and the second image (5) are combined” means that some areas (first significant information (9)) overlap, Another partial area (second significant information (10)) is fitted together to indicate a state in which the first image (4) and the second image (5) are printed together. Therefore, the first significant information (9) of the first image (4) and the first significant information (9) of the second image (5) have the same shape, size and arrangement position, and similarly, The second significant information (10) of the first image (4) and the second significant information (10) of the second image (5) also have the same shape, size, and arrangement position. Therefore, when the first image (4) and the second image (5) are stacked, the first significant information (9) and the second significant information (10) are fitted together.

  Specifically, if the first image (4) is formed of gray or black ink, the second image (5) may be silver glitter ink, and the first image (4). Is formed with yellow or orange colored ink, the second image (5) may be gold glitter ink.

  The glitter ink is an ink containing a glitter material having a characteristic of strongly reflecting light in the ink. As inks that are commercially available as offset inks, there are silver inks and gold inks called metallic inks, and pearl inks containing special pearl pigments may be used. In addition, there is no problem even if a color pigment is mixed in addition to the glittering material. There is no problem even if the color of the color pigment is any color such as black, red, blue or yellow. However, when an excessive amount of pigment is mixed, even if the second image (5) is formed in the range of the appropriate halftone dot area ratio, the gradation expression area is too widened under regular reflection light. In this observation, an event occurs in which the second image (5) does not completely disappear. Therefore, in the case of mixing any of the colored pigments, it is desirable to keep the amount within a range that does not exceed a half of the blending ratio of the glittering material in the ink.

  The aforementioned glittering material may be a general metal powder pigment such as aluminum powder, copper powder, zinc powder, tin powder, brass powder, or iron phosphide. Further, general pearl pigments such as iris pearl pigments and scale pigments, functional pigments such as glass flake pigments and cholesteric liquid crystal pigments may be used.

  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. Yes, specifically, the intensity distribution of a specific wavelength in the visible light region (400 to 700 nm) is shown. In the present invention, “the hue is the same” means that the colors of red, blue, and yellow are the same in the two colors, and the wavelength intensity distribution in the visible light region has a correlation in the two colors. . In the present invention, achromatic colors such as “white”, “ash”, and “black” are considered to belong to one same hue.

  Here, the structure of the light and shade of the second image (5) will be described. The shade of the second image (5) is the shade of the first image (4) superimposed at the same position from the shade of the first significant information (9) indicated by the printed image (3) under diffuse reflected light. Determined by subtracting. As an example, specific images and numerical values are shown in FIG.

  The first significant information (9) shown in the printed image (3) under diffuse reflected light is a binary image expressed by two shades of a dark portion and a light portion, and the printed image (3) under regular reflected light. Similarly, the second significant information (10) represented by) will be described as an example of a binary image expressed by two shades of a dark portion and a light portion.

  Here, the dark part (3A) representing “A” of the first significant information (9) in the printed image (3) is 1.0 in reflection density, and the light part (3Back) constituting the other background is The dark portion (4A) having a reflection density of 0.5 and showing the first significant information (9) of the first image (4) has a reflection density of 0.2 and the second significant information (10). It is assumed that the dark portion (4B) that expresses the reflection density is 0.5, and the other light portion (4Back) that expresses the background is 0 in the reflection density. In this case, since the density of the second image (5) is obtained by subtracting the density of the first image (4) formed in the same area from the printed image (3), the second image (5) ) In the region overlapping the light portion (4Back) forming the background of the first image (4), that is, the region (5Back) representing the background other than the characters “A” and “B” Since the reflection density of the light part (4Back) of (4) is 0, the reflection density of the printed image (3) is inherited as it is.

  That is, the area (5Back) showing the background other than the characters “A” and “B” has a reflection density of 0.5. On the other hand, the region (5B) showing only the letter “B” (4B) of the alphabet in the second image (5) has a reflection density of 0.5 from the background (3Back) of the printed image (3). The reflection density obtained by subtracting the reflection density of 0.5 of the letter “4” (4B) of the alphabet of one image (4), that is, the reflection density is 0.

  Further, the region (5A) showing only the letter “A” of the alphabet of the second image (5) is obtained from the reflection density 1.0 of the region (3A) showing “A” in the printed image (3). The reflection density of 0.8 is subtracted from the reflection density of 0.2 in the area (4A) showing only “A” in the first image (4). Finally, the region (5AB) in which the alphabets “A” and “B” of the second image (5) overlap is the reflection density 1 of the region (3A) representing “A” in the printed image (3). The reflection density of 0.5 is subtracted from the reflection density of 0.5 in the area (4A) showing only “B” in the first image (4) from 0.0.

  The shade of the second image (5) is determined by the above calculation. The first significant information (9) and the second significant information (10) are both binary images. However, the present invention is not limited to this. Without any problem, the color density can be calculated by the same method and the shade can be designed. These shade designs are not calculated as described above, and there is no problem even if they are automatically performed during image processing using image software. As described above, the density of the first significant information (9) in the printed image (3), and the density of the first significant information (9) and the second significant information (10) in the first image (4). Is determined, the shade of the second image (5) is automatically determined. The above is the description of the shade structure of the second image (5).

  Regarding the design of the area ratio of the second image (5), basically, the greater the difference between the maximum area ratio and the minimum area ratio, the visibility and regular reflection of the first significant information (9) under diffuse reflection light. Since the visibility of the second significant information (10) under light is improved, it is desirable that the difference in the area ratio in the second image (5) is large. For this reason, the difference between the maximum area ratio and the minimum area ratio of the area ratio of the second image is desirably greater than at least 50%, and more desirably 75%. The above is the description of the second image.

  Next, the stacking order of the first image (4) and the second image (5) will be described with reference to FIG. As shown in FIG. 4A, the anti-counterfeit printed matter (1) of the present invention prints the second image (5) on at least a part of the substrate (2), and then the first image (4). ) Or after printing the first image (4) on at least a part of the substrate (2) as shown in FIG. 4 (b), the second image (5) is printed. The image may be printed, and the effect of changing the image appears if they are combined regardless of the printing order of the first image (4) and the second image (5).

  In particular, in the configuration in which the background (4Back) other than “A” and “B” of the first image (4) as in the first embodiment is white (with an area ratio of 0%), which image is the top image. However, there is almost no difference in effect. On the contrary, when the background (4Back) other than “A” and “B” of the first image (4) has a constant color density, it is more effective to use the configuration of FIG. is there. This is because the light incident on the second image (5) is not hindered by the first image (4). As described above, it is desirable to properly use the stacking order according to the configuration.

  As the positional relationship of printing, the first significant information (9) of the two images of the first image (4) and the second image (5) is accurately superimposed, and the second significant information (10 ) Are required to be fitted accurately. However, for the purpose of ensuring the redundancy of printing, there is no problem even if an overlap portion is provided in the contour portions of the first significant information (9) and the second significant information (10).

  The effect of the forgery prevention printed matter (1) produced with the above structure is demonstrated using FIG. The positional relationship among the light source (6), the anti-counterfeit printed matter (1), and the observer (7) is shown in FIG. 5A as an observation angle where the diffusely reflected light is dominant (the incident angle of light incident on the printed matter). (Α) and the angle at which the reflection angle connecting the observer and the printed material is greatly different (in this example, 0 degrees)), the observer is given the alphabetic character “9” as the first significant information (9). The letter “A” is visible. Under the diffuse reflected light, the letter “B” of the alphabet which is the second significant information (10) cannot be visually recognized.

  On the other hand, the anti-counterfeit printed matter (1) is obtained as shown in FIG. 5 (b) by using the angle at which specular reflection light is dominant (the angle (α) of light incident on the printed matter, When observed within an angle range in which the reflection angle (β) is approximately the same value), the letter “A”, which is the first significant information (9) indicated by the first image (4), is completely And the letter “B” as the second significant information (10) is visually recognized. In this technique, even if the base material (2) is a coated paper, the first significant information (9) does not appear in the negative-positive reversal under regular reflection light, which was the conventional technique, It has the effect of disappearing completely visually.

  The basic principle of changing two images of the present invention is as follows. The first significant information (9) is visually recognized by the difference in light and shade in the printed image (3) at the observation angle where the diffuse reflected light shown in FIG. 5 (a) is dominant. The first image (4) and the second image (5) are combined so that the second significant information (10) is concealed in the light and shade of the first significant information (9). Since it is designed, the presence of the second significant information (10) is not visually recognized under diffuse reflected light, and the first significant information in the printed image (3), which is a composite image of the two images. Only (9) is visually recognized by the shade of a specific hue.

  On the other hand, at the observation angle where specular reflection light is dominant as shown in FIG. 5B, the second image (5) in the printed image (3) reflects light very strongly. The image (4) hardly reflects (it does not change from the state of reflection under diffuse reflection). The reflected light produced by specularly reflecting the incident light of the first image (4) composed of glittering ink is extremely strong, so that the observer cannot grasp the intensity of the reflected light amount. As a result, the entire image can be recognized only when it emits strong light (when formed on coated paper, the first significant information (9) is visually recognized in a negative / positive inverted state).

  For this reason, while the second image (5) is visually lightly changed under specular reflection light, the light and shade is compressed, while the light and shade of the first image (4) is not changed. For this reason, in the first image (4), the second significant information (10) formed by the colored ink in a relatively darker shade is visualized by the difference in brightness from the surrounding area. Of the first image (4), the first significant information (9) formed by coloring ink in a relatively light shade is the first significant information (9) of the second image (5) and its Compete with each other. Originally, the first significant information (9) of the second image (5) has the highest brightness under specular reflection light, and in some cases, negative / positive reversal under specular reflection light is viewed by an observer. However, it is canceled by the shade of the second significant information (10) of the first image (4), and disappears completely under specular reflection light. Even if the first significant information (9) does not disappear completely, the contrast is extremely small as compared with the conventional technique, and an effect is produced. As a result of the above, the second significant information (10) is visually recognized under regular reflection light. This is the principle by which an image change effect occurs in the forgery-preventing printed material (1) of the present invention.

  As described above, according to the configuration of the present invention, the first significant information (9) is assigned to each of the two images, and is configured by superimposing them. For this reason, the first significant information (9) can be formed darker than in the prior art, and even though it is formed darker, it disappears without appearing in negative-positive reversal under regular reflection light. For this reason, while the visibility of the 1st significant information (9) under diffuse reflection light improves remarkably, the visibility of the 2nd significant information (10) under regular reflection light also improves two effects. Can be obtained at the same time.

  In the present invention, the angle where the diffusely reflected light is dominant refers to an angle where there is almost no specularly reflected light and the ratio of the diffusely reflected light is extremely large. On the other hand, the angle where the regular reflection light is dominant refers to an angle where the diffuse reflection light is extremely small and the ratio of the regular reflection light is very large.

  As described in the problem to be solved by the invention, when synthesizing the first image (4) and the second image (5), the outlines of the boundary portions of the respective images are thickened to overlap the two images. By doing so, the redundancy of printing can be ensured. The appropriate range of the two images of the first image (4) and the second image (5) varies depending on the color density of the glitter ink and the colored ink itself. Even if an overlapping area of about 2 mm is provided, the visibility is hardly affected.

  Luminescent pigments such as fluorescent pigments, phosphorescent pigments and phosphorescent pigments, IR absorbing pigments, photochromic pigments, temperature indicating materials, thermochromic materials and other functional materials may be added to each ink. In this case, in addition to the image switching effect Various functionalities can be added.

  The printing method of the anti-counterfeit printed material in the present invention can be formed by any printing method such as offset printing, flexographic printing, letterpress printing, gravure printing, screen printing, intaglio printing, and the like. In addition, if it is possible to use metal ink, it can be formed by various digital output machines such as IJP, laser printers, sublimation printers, etc. In this case, so-called variable printing that changes the information of one output item. Can be implemented.

  In the present embodiment, the alphabet which is a binary image is used for the first significant information (9) and the second significant information (10). However, the present invention is not limited to this. Alternatively, a multi-tone image such as a picture may be used.

Subsequently, as a second embodiment, a third image (8 ′) constituted by a streaked image line is arranged between the first image (4 ′) and the second image (5 ′). An example will be described. In this case, not only the first significant information (9) and the second significant information (10) can be visually recognized under diffuse reflection light and regular reflection light, but also in an angular range in which diffuse reflection light and regular reflection light are mixed. The third significant information (11) can be visually recognized, and a more excellent change effect can be exhibited. This will be specifically described below.
(Second embodiment)

  First, the forgery prevention printed matter (1 ') of the second embodiment is shown in FIG. The anti-counterfeit printed matter (1 ') has a printed image (3') having a color different from that of the substrate (2 ') on the substrate (2'). The image shown in FIG. 6A is an image that can be seen in the printed image (3 ′) under diffuse reflection light, and the image shown in FIG. 6B is an observation in which diffuse reflection light and regular reflection light are mixed. The image that is visible in the printed image (3 ′) at an angle and that is shown in FIG. 6C is an image that is visible in the printed image (3 ′) under specular reflection light. As shown in FIG. 6A, the printed image (3 ') shows the first significant information (9) under diffuse reflected light.

  In the present embodiment, the first significant information (9) is the letter “A” in the positive alphabet in which the character portion is darker than the surroundings. Further, as shown in FIG. 6B, the printed image (3 ') shows the third significant information (11) at the observation angle where the diffuse reflection light and the regular reflection light are mixed. In the present embodiment, the third significant information (11) is the letter “C” in the positive and negative alphabets. Finally, as shown in FIG. 6C, the printed image (3 ') shows the second significant information (10) under regular reflection light. The second significant information (10) in the present embodiment is the letter “B” in the positive alphabet, in which the character portion appears darker than the surroundings.

  The print image (3 ') is formed by combining three images as shown in FIG. The three images are a first image (4 '), a second image (5'), and a third image (8 '). Note that the density configuration of the printed image, the configuration, density, material, production method, and the like of the first image (4 ′) and the second image (5 ′) are the same as in the first embodiment. The description is omitted, and the third image (8 ′) will be specifically described here.

  The configuration of the third image (8 ') will be described with reference to FIG. The third image (8 ') is constituted by a set of image lines having a bulge. Specifically, the pattern includes a pattern portion (8A ') in which the third significant information (11) appears in a positive state and a background portion (8B') in which the third significant information (11) appears in a negative state.

  The pattern portion (8A ′) is arranged in a line shape in the first direction (S1 direction in the figure) with the convex image line having a bulge having the image line direction in the second direction (S2 direction in the figure). Thus, the background portion (8B ′) has a protruding image line having a bulge having an image line direction in the first direction (direction S1 in the figure) and in the second direction (direction S2 in the figure). It is arranged in a line. The convex lines constituting the pattern portion (8A ') and the background portion (8B') do not overlap each other.

  In the present invention, “arranged in a line” means a state in which a plurality of convex image lines are arranged in the same direction. Desirably, the pitches of the plurality of projected image lines arranged are regularly arranged at the same pitch, but are not limited to the same pitch.

  The pattern portion (8A ') and the background portion (8B') may be basically formed with the same line area ratio, or may be formed with different line area ratios. However, when a colored ink other than transparent or translucent is used to form the third image (8 ′), the pattern area (8A ′) and the background area (8B ′) have the same line area ratio. It is necessary to form with. This is to prevent the third significant information (11) included in the third image (8 ') from being visualized under diffuse reflected light.

  The third image (8 ') may be formed by any method as long as the third image (8') is composed of an image line having a bulge. That is, any printing method such as flexographic printing, letterpress printing, gravure printing, intaglio printing, and screen printing, which are printing methods capable of forming a certain bulge, may be used. The height of the bulge needs to be at least 2 μm, and is preferably 5 μm or more.

  The third image (8 ') may be formed in any color as long as it has light transparency. It may be transparent, translucent or colored. However, it should not have such a light blocking property that the incident light is completely absorbed or reflected so that the underlying image cannot be seen.

  Further, it is desirable that the third image (8 ') has a color flip-flop property or a light-dark flip-flop property. Color flip-flop property refers to a characteristic that changes to a hue different from the hue under diffuse reflected light under specular reflection light, and light and dark flip-flop property changes the lightness from the color under diffuse reflected light under regular reflected light. Refers to characteristics. Any of these characteristics is preferable because the color change when the second significant information (10) or the third significant information (11) appears increases and the color expression becomes richer.

  As a method for imparting color flip-flop properties, common pearl pigments such as iris pearl pigments and scaly pigments, glass flake pigments, and cholesteric liquid crystals are used in the ink that forms the third image (8 ′). It is desirable to mix functional pigments having color flip-flop properties such as pigments. Also, the easiest way to provide bright and dark flip-flops is to use a glossy medium. In addition, a general metal powder pigment such as aluminum powder, copper powder, zinc powder, tin powder, brass powder, or iron phosphide may be mixed to such an extent that the permeability is not lost.

  In addition, functional materials such as fluorescent pigments, phosphorescent pigments, phosphorescent pigments and other light-emitting pigments, IR-absorbing pigments, photochromic pigments, temperature indicating materials, and thermochromic materials may be added to the ink that forms the third image (8 ′). In this case, various functionalities can be added in addition to the image switching effect. The above is the description of the third image (8 ').

  Next, the stacking order of the first image (4 '), the second image (5'), and the third image (8 ') in the second embodiment will be described with reference to FIG. As shown in FIG. 9A, the anti-counterfeit printed matter (1 ′) of the present invention prints the second image (5 ′) on the substrate (2), and then displays the third image (8 ′). After printing, the first image (4 ′) may be printed, or after printing the first image (4 ′) on the substrate (2) as shown in FIG. The third image (8 ′) may be printed, followed by the second image (5 ′).

  That is, if the first image (4 ') and the second image (5') are combined regardless of the printing order with the third image (8 ') interposed therebetween, an image change effect is exhibited. In the second embodiment, in the laminated state of FIG. 9B, the third significant information (11) appearing in the angle region where the diffuse reflection light and the regular reflection light are mixed, and under the regular reflection light. Since the visibility of the 2nd significant information (10) which appears appears, it is more desirable. This is because the reflectance of the second image (5 ') is increased by the third image (8'). However, a sufficient effect is produced even in the stacking order of FIG. Since others are the same as those of the first embodiment, they are omitted.

  The effect of the anti-counterfeit printed matter (1 ') produced with the above configuration will be described with reference to FIG. When the positional relationship among the light source (6 ′), the anti-counterfeit printed matter (1 ′), and the observer (7 ′) is observed at an observation angle where diffuse reflected light is dominant as shown in FIG. The observer visually recognizes the letter “A” of the alphabet as the first significant information (9). Under diffuse reflection, the letter “B” of the alphabet as the second significant information (10) and the letter “C” of the alphabet as the third significant information (11) cannot be visually recognized.

  On the other hand, the anti-counterfeit printed matter (1 ′) is obtained by changing the angle at which the diffuse reflected light and the regular reflected light are mixed (the angle (α) of the light incident on the printed matter) and the observer (7 ′) as shown in FIG. ) And the printed material (1 ′), the first significant information (9) indicated by the first image (4 ′) is observed in an angle range where the reflection angle (β) is a close value. The character “A” is completely disappeared, and the character “C” as the third significant information (11) is visually recognized. The letter “C” is negative-positive inverted as the angle of incident light changes.

  Finally, when the specularly reflected light is observed at a dominant angle, “A” which is the first significant information (9) indicated by the first image (4 ′) and the third image (8). The character “C”, which is the third significant information (11) represented by “), disappears completely, and the character“ B ”, which is the second significant information (10), is visually recognized. In the present technology, even if the base material (2 ′) is coated paper, the first significant information (9) does not appear in the negative / positive inversion under the regular reflection light as in the conventional technology. It has the effect of disappearing completely visually. The above is the effect of the present invention.

  Subsequently, the principle of the above-described effect will be described. The first significant information (9) is visually recognized by the difference in light and shade in the printed image (3 ') at the observation angle where the diffuse reflected light is dominant as shown in FIG. The first image (4 ′) and the second image (5 ′) are combined so that the second significant information (10) is concealed in the shade of the first significant information (9). Since the shade is designed, the presence of the second significant information (10) is not visually recognized under diffuse reflected light, and the third image (8 ') is colorless, transparent, translucent, or colored. Even in this case, since the area ratio of the pattern portion (8A ′) and the background portion (8B ′) is the same line drawing design, it is invisible in this angle region. Therefore, in the printed image (3 '), only the first significant information (9) is visually recognized by the shade of a specific hue.

  At the observation angle where diffuse reflection light and regular reflection light are mixed as shown in FIG. 10B, the three-dimensional structure of the object is most emphasized. Of the printed image (3 ′), only the third image (3 ′) is composed of a raised image line, and the amount of reflected light varies depending on the direction of each image line of the raised image line at this observation angle. As a result, the third significant information (11) appears. Since the image line close to the relationship in which the incident light and the image line direction are parallel reflects light more strongly, the pattern portion (8A ′) shines strongly or the background portion (8B ′) depends on the angle of the incident light. The intensity of the light changes, and the negative / positive inversion effect of the image is produced. At this observation angle, the second significant information (10) may be visualized, but the contrast is relatively very small compared to the contrast of the third significant information (11). Only significant information (11) is visually recognized.

  At the observation angle where the regular reflection light is dominant as shown in FIG. 10C, the difference in the reflectance of the material constituting each image is emphasized more than the three-dimensional structure of the object. Therefore, as in the first embodiment, the second image (5 ′) and the third image (8 ′) reflect light very strongly, but the first image (4 ′) hardly reflects. As a result, the second significant information (10) is visually recognized. This is the principle that an image change effect occurs in the forgery-preventing printed matter (1 ') of the present invention.

  In the present invention, the “observation angle in which diffusely reflected light and specularly reflected light are mixed” is different from an angle in which diffusely reflected light is dominant or an angle in which specularly reflected light is dominant. Refers to an angular region where the same degree exists.

  Hereinafter, examples of the anti-counterfeit printed matter (1) specifically produced according to the embodiment for carrying out the invention will be described in detail, but the present invention is not limited to these examples.

  Example 1 of the present invention will be described with reference to FIGS. 1 to 5 as in the first embodiment. In Example 1, white coated paper (Espricoat FM manufactured by Nippon Paper Industries Co., Ltd.) was used as the base material (2).

  The first image (4) is printed with a gray matte colored ink (UVL special training P420C matte gray, manufactured by T & K TOKA), and the second image (5) is a silver ink (UV No. .3 Silver Co., Ltd. was used for printing. The two images were combined in the stacking order shown in FIG. 4B to form a printed image (3). The density of each image was the density shown in FIG. The gray matte colored ink had a reflection density of about one-third that of silver ink.

  FIG. 5 shows the effect of the anti-counterfeit printed matter (1) of the present invention. FIG. 5A is an image observed when the observer observes the anti-counterfeit printed matter (1) under diffuse reflected light. In the printed image (3), the first significant information (9 The letter “A” of the alphabet is visually recognized. On the other hand, as shown in FIG. 5B, when the observer observes the anti-counterfeit printed matter (1) at a specific observation angle where the regular reflection light is dominant, “A” is displayed from the printed image (3). The character “B” of the alphabet which is the second significant information (10) was visually recognized instead. At this time, the letter “A”, which is the first significant information (9) as in the prior art, did not appear in the negative / positive inversion.

1, 1 'anti-counterfeit printed matter 2, 2' base material 3, 3 'printed image 4, 4' first image 5, 5 'second image 6, 6' light source 7 observer's viewpoint 8 'third Image 8A 'Pattern part 8B' Background part 9 First significant information 10 Second significant information 11 Third significant information

Claims (3)

At least a part on the substrate is provided with a printed image that exhibits the first significant information under diffuse reflected light and the second significant information under specular reflected light,
The printed image is formed by laminating a first image formed with a colored ink having a color different from that of the substrate and a second image formed with a glitter ink having the same hue as the colored ink,
Based on the gradation of the first significant information that appears under the diffuse reflected light and the second significant information that appears under the regular reflected light,
The first image is divided into first significant information and second significant information in a state where each gradation is not inverted by making the shades different,
The second image is divided into the first significant information in a state where the gradation is not inverted and the second significant information in a state where the gradation is inverted by making the shades different.
The first significant information and the second significant information of each of the first image and the second image are formed with the same shape, size, and arrangement position,
The forgery-preventing printed matter, wherein the first significant information is visible under diffusely reflected light, and the first significant information is lost and only second significant information is visible under regular reflected light. The printed image includes a third image laminated between the first image and the second image with an ink having at least one of light-dark flip-flop property or color flip-flop property,
The third image is divided into a pattern portion and a background portion by arranging raised convex lines in a line, and the arrangement direction of a part of the line-shaped convex lines is different. Is formed with significant information,
The forgery-preventing printed matter according to claim 1, wherein the third significant information can be further visually recognized in an area where diffuse reflection light and regular reflection light are mixed. The forgery-preventing printed matter according to claim 1 or 2, wherein the difference between the maximum and minimum halftone dot area ratio of the second image exceeds 50%.

Images