JP2009202570A - Image forming body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide forgery-preventive printed matter having a high level of freedom in design, allowing for the incorporation of a latent image into a color design and with the latent image hardly visible not only to the naked eye but even through a highly efficient scanner, with difficulty for forging or copying, having a high forgery-preventive effect and capable of easily performing a true/false judgement through the use of an examination device. <P>SOLUTION: The image forming body having a high level of design freedom, allowing for the incorporation of latent images into a color design and having a high forgery-preventive effect is provided in which an image is formed by halftone dots and in which the image includes a non-latent image section with halftone dots of uniform pitches being formed and a latent image section with halftone dots being shifted by about 1/2 pitch in relation to the pitch forming the non-latent image section. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is effective in preventing counterfeiting of securities such as banknotes, gift certificates, admission tickets, stock certificates, and printing media such as packages, product labels, and the like, and image formation for counterfeiting that is particularly difficult to copy by copying or scanning About the body.

  Countermeasures against counterfeiting are indispensable for securities such as gift certificates, admission tickets, cash vouchers, stock certificates, and claims. Conventionally, printed matter that can be read mechanically and optically as electronic data after use, such as gift certificates, printed matter that makes counterfeiting and forging more difficult, and does not interfere with design and appearance, or color Printed products that have been provided with anti-counterfeit measures such as printed materials that are difficult to be copied by a copy or a scanner are widely used in the market.

  As one of the printing application technologies that make counterfeiting and forging more difficult, for example, the pitch is approximately ½ pitch between the latent image portion and non-latent image portion of many lines (striped parallel lines with the same pitch). When a line film of the same shape as this line is superimposed on the printed matter that has been shifted, the part (latent image) where the line is shifted becomes visible as a pattern. In addition, there is a method that uses a technique to create a latent image by shifting a sequence of neatly arranged halftone dots. When overlapping halftone dot films with the same pattern, the part where the halftone dots are shifted (latent image) is used as a pattern. Visible.

However, in the method using this technology, the pattern itself is relatively simple, so the latent image pattern is easy to be detected by operations such as image enlargement, and can be easily created by those who have some knowledge and technology. Therefore, there was a problem in terms of preventing forgery. As a countermeasure, for example, Patent Document 1 discloses several types of latent lines with line patterns configured by using several types of line pitches and several types of line angles on an image forming sheet such as a single printing sheet. A technique is disclosed that requires a line sheet for visualization (for authenticity determination) in which two or more types of line patterns are formed to determine the authenticity of an image formed body by forming an image.
JP 2007-15120 A

  However, the configuration of Patent Document 1 is more complicated and difficult to forge and duplicate compared to the above-described technology, but due to the high performance of scanners and the like, fine latent image patterns can be visually recognized and forged. There is also a possibility of becoming.

  The present invention has been made in order to solve the above-mentioned problems, and the problem is that the degree of freedom of design is high, the latent image can be incorporated into the color design, and the latent image is of course the naked eye. It is an object of the present invention to provide an anti-counterfeit printed matter that is difficult to be seen even with a high-performance scanner, has a high anti-counterfeit effect, and is difficult to forge and duplicate.

  In order to solve the above-described problems, the present invention provides an image forming body in which an image composed of a latent image portion and a non-latent image portion is formed on a substrate, and the non-latent image portion is a halftone dot having a uniform pitch. The latent image portion is composed of halftone dots shifted by about ½ pitch with respect to the halftone dots of the non-latent image portion.

  In addition, the present invention is the image forming body including the plurality of latent image portions having different directions in which the halftone dots are shifted by approximately ½ pitch with respect to the halftone dots of the non-latent image portions.

  The present invention is the image forming body, wherein the image is formed of a plurality of color halftone dots having different halftone dot angles.

  In addition, the present invention is an image forming body characterized in that there are a plurality of regions having different halftone dot pitches for forming the image.

  In addition, the present invention is an image forming body in which at least one color halftone dot is formed of fluorescent ink.

  Since the present invention is configured as described above, the following effects can be obtained.

  That is, according to the present invention, since the image is formed with halftone dots, the degree of freedom in design is high, and an image composed of multiple colors can be printed by shifting the halftone angle, so full-color printing is also possible. Further, it provides an image forming body in which the latent image is hardly visible with the naked eye compared with the case where the latent image is formed with a line, and is difficult to be visually recognized with a high-performance scanner or the like. It becomes possible.

  Hereinafter, an image forming body according to an embodiment of the present invention will be described in detail with reference to the drawings.

  In the image forming body according to the present invention, an image by halftone dots is formed, and the image is approximately ½ with respect to a non-latent image portion having a uniform pitch and a uniform pitch of halftone dots of the non-latent image portion. And a latent image portion having a pitch shift.

  FIG. 1 is an enlarged schematic diagram illustrating two-change latent images that respectively appear in two colors (for example, magenta and cyan) having different halftone dot angles, according to an embodiment of the image forming body of the present invention.

  FIG. 1A is an enlarged schematic view of halftone dots constituting an image as viewed from above. As shown by the halftone dots existing on the line indicating the pitch in the figure (which does not actually exist), the non-latent image portion composed of halftone dots having a uniform pitch, and the pitch with respect to the non-latent image portion is approximately And a latent image portion composed of halftone dots shifted by ½ pitch. An image is formed by a set of large and small halftone dots. The latent image portion may be formed in an arbitrary shape such as a character, a picture, a symbol, or a pattern.

  FIG. 1B is a schematic enlarged view of a state in which a verification tool on which a line pattern having the same pitch as the halftone dots of the image forming body is formed is superimposed on the image forming body, and FIG. FIG. 6 is a schematic enlarged view of a state in which a verification tool in which a halftone dot pattern having the same pitch as a halftone dot is formed is superimposed on an image forming body. A transparent film or the like is used as the base material of the verification tool.

  Since the image forming body of the present invention has the above-described configuration, it is possible to print in multiple colors by changing the dot angle, unlike the case of forming a latent image with a conventional line pattern. is there. Thus, since an image can be formed with a multicolor halftone dot pattern, the latent image portion is hardly visible in a normal state, and an image forming body with improved security can be provided. Note that a plurality of latent image portions may exist for each color, and design is possible freely.

  In addition to the halftone dots on which an image is formed with normal ink, the image forming body may be printed with fluorescent ink. In this case, although it cannot be visually recognized by normal visual observation, an image can be confirmed when it is applied to a dedicated light source, and when a verification tool is stacked, a latent image of fluorescence appears, which is captured by a color copy or a scanner. It is possible to further improve security. In addition, it can be printed over normal ink, and both latent images can be visually recognized due to its characteristics. Fluorescent inks are currently available in three colors, and using each one can expand the variation.

  FIG. 2 is another example of an embodiment of the image forming body of the present invention, and illustrates an image forming body having a plurality of latent image portions (here, two changes) that appear when the overlapping angle of the verification tool is changed. FIG.

  The image forming body shown in FIG. 2 has a latent image portion (1) in which the halftone dots are shifted by approximately ½ pitch in a certain direction (here, right side with respect to the halftone angle) with respect to the halftone dots of the non-latent image portion. (Next) 9 and a latent image portion (secondary) 10 in which halftone dots are shifted by approximately ½ pitch in another fixed direction (here, directly below the halftone angle). Thereby, when the angle at which the verification tool is stacked is changed, only the latent image portion 9 is visualized, and only the latent image portion 10 is visualized. Become a body.

  Further, as in the embodiment of the image forming body shown in FIG. 3, a plurality of latent images can be visualized at the same place by utilizing the characteristics of halftone dots.

  In the case of multi-color printing, this can be performed separately for each color, and an arbitrary number of colors can be incorporated. However, in consideration of the ease of discriminating a latent image, 2 for each color. In order to improve the visibility of the latent image portion when the image is visualized, the halftone dot of the two latent image portions should have a halftone dot angle with respect to the halftone dot of the non-latent image portion. As a reference, it may be shifted by 90 degrees in the horizontal and vertical directions. Thereby, in the case of four-color printing, a latent image that changes four colors × 2 changes = 8 can be formed, and an image forming body rich in various variations can be provided (see FIG. 6). Further, there may be a plurality of latent image portions having different directions for shifting the halftone dots.

  FIG. 4 is another embodiment of the image forming body according to the present invention, and FIG. 4A is an enlarged schematic view for explaining the image forming body in which a plurality of regions having different halftone dot pitches exist. . The image forming body includes regions 13 and 14 having different pitches.

  4B is an enlarged view of a state in which a verification tool on which a line pattern having the same pitch as the halftone dots forming the non-latent image portion included in the region 13 is superimposed on the image forming body of FIG. It is a schematic diagram. In FIG. 4B, the latent image formed in the region 13 is visualized, but the latent image formed in the region 14 cannot be confirmed.

  FIG. 4C is an enlarged view of a state in which a verification tool on which a line pattern having the same pitch as the halftone dots forming the non-latent image portion included in the region 14 is superimposed on the image forming body in FIG. It is a schematic diagram. In FIG. 4C, the latent image formed in the region 14 is visualized, but the latent image formed in the region 13 cannot be confirmed. In addition, as shown in FIG. 1, the verification instrument may be formed with a halftone dot pattern instead of a line pattern.

  In FIG. 4, the regions having different pitches are two regions. However, the present invention is not limited to this, and a plurality of regions can be formed, and the shape of the regions may be formed in an arbitrary shape. Further, even if the areas are different, there may be areas where a halftone dot pattern is formed at the same pitch, and it is possible to freely design an image forming body having a wide variety.

  Accordingly, it is necessary to prepare a plurality of verification instruments having different line patterns or halftone dot pitches, or verification instruments that completely match the image forming body region and the pitch formed on each. Even if the presence of the latent image is noticed, it is difficult to confirm all the latent images, so that even if some of the latent images are counterfeited / tampered, it is possible to reliably determine whether the images are forged.

  It is also possible to reduce the halftone dot pitch in some areas so that the image is crushed when trying to capture it with a color copy or a scanner. As an actual numerical value, when the number of halftone lines to be configured is 177 lines or more, it is difficult to confirm a latent image, and forgery is difficult.

  Next, a manufacturing method of an embodiment of the image forming body of the present invention will be described.

  Conventional printing-related equipment can be used to create an image with halftone dots used in the present invention, and a latent image is incorporated from data obtained by halftoning an image by normal plate making screening.

  First, image data incorporating a latent image is created. For example, a picture such as a photograph or an illustration into which a latent image is to be inserted is selected, and the number of lines (pitch or pitch) and angle (screen angle) to be used are set. Thereafter, four color separations are performed to obtain halftone dot data of K (black), M (magenta), C (cyan), and Y (yellow). At this time, the data format is not particularly limited.

  Next, a pattern, a character, a symbol, a pattern, or the like to appear as a latent image is selected, and a latent image mask is produced. As described above, it is possible to cause a latent image that changes two times for each color, but as an example, a two-change latent image of latent images 1 and 2 on a C (cyan) plate with a halftone dot angle set to 45 degrees, Assume that a total of four latent images, that is, two-change latent images of latent images 3 and 4, are put in an M (magenta) plate having a halftone dot angle set to 15 degrees. (See Figure 5)

  In this case, three data are required for the C (cyan) version. (1) As-is data obtained by four color separations, (2) Data obtained by adding the data of the latent image 1 to the data obtained by moving the halftone of the halftone used in the horizontal direction with respect to the halftone angle of 45 degrees. 3) The data of the latent image 2 is added to the data obtained by shifting the halftone pitch of the used halftone dot in the perpendicular direction (vertical direction) with respect to the halftone dot angle of 45 degrees. Making a plate.

  Similarly, the M (magenta) version also requires three pieces of data. (1) As-is data obtained by four color separations, (2) Data obtained by adding the data of the latent image 3 to the data obtained by moving the halftone of the used halftone in the lateral direction with respect to the halftone angle of 15 degrees. 3) The M (magenta) version is obtained by combining the three data of the data obtained by adding the data of the latent image 4 to the data obtained by shifting the halftone pitch of the used halftone dot in the perpendicular direction (vertical direction) with respect to the halftone dot angle of 15 degrees. Making a plate.

  As shown in FIG. 5, the halftone dots of the latent image portion and the non-latent image portion may not be complete halftone dots, but may be divided halftone dots depending on the design of the latent image portion. .

  The data of the K (black) plate (halftone dot angle of 60 degrees) and the Y (yellow) plate (halftone dot angle of 75 degrees) are made as they are obtained by the four-color plate. The above-described C, M, Y, and K plates can be overlaid to produce image data containing a latent image.

  In this example, the pitch of the halftone dots is 0.3 mm. The dot pitch is preferably 0.05 mm to 2.5 mm. If the pitch is less than 0.05 mm, it is difficult to reproduce the image due to the expansion and contraction of the base material and the registration accuracy of each color, and the image has a low contrast. On the other hand, if the pitch exceeds 2.5 mm, the shift of the halftone dot pattern of the latent image portion becomes easy to visually recognize, and the presence of the latent image is read and the forgery prevention effect is lowered. Although it depends on the complexity of the image used and the smoothness of the base material, it is generally recommended that the width of the light transmitting part and the light blocking part of the verification tool be 0.15 mm at a pitch of 0.3 mm. The The pitch deviation for forming the latent image portion can be used in the range of 1/4 to 3/4, but it can be used, but 1/2 is suitable for developing a latent image with high contrast. .

  The image forming body of the present invention uses the C, M, Y, and K plates made with the above-described data and uses the inks of the respective hues on the base material such as paper and plastic film to register the pattern. It is formed by printing together. Note that this is a case of four color separation, but the image forming body of the present invention is not limited to this, and may be four colors or less, and using special colors as in normal printing. Alternatively, a single or a plurality of fluorescent inks may be used.

  The substrate is not particularly limited, such as paper used for securities applications or paper media such as paperboard used in packages, plastics, etc., and can be widely applied to papers with printed matter and watermarks. The printing method can be selected as appropriate in consideration of the area of the pattern, the material of the base material, the quantity to be created, etc., and can also be performed by sheet-fed printing or rotary printing. Reproduction of halftone dots such as offset method or gravure method There is no particular limitation as long as it is a method that ensures the property.

  In addition to the printing method described above, the image forming body of the present invention can also be printed by on-demand printing using a copying machine. In that case, it is possible to print a latent image to be visualized separately on each printed matter, that is, to handle “variable data”. Thereby, for example, a sheet on which a latent image necessary for each individual is printed can be produced by direct mail or the like.

  Regarding on-demand printing methods, the latent image data made during normal printing can be used as it is on an on-demand printing machine, so it can be printed without using film or printing plate materials. Can be omitted.

  In the image forming body produced as described above, only images such as photographs and illustrations are visualized on the surface as it is. Here, by applying a verification tool in which a halftone dot or a line pattern having the same pitch as the halftone dot pattern is applied to the image forming body, it can be visually recognized by combining the pattern provided in the verification tool and the latent image portion. A latent image having various patterns, symbols, characters, patterns, etc. is visualized.

FIG. 3 is an enlarged schematic diagram illustrating an image forming body in which a latent image portion is formed in each of two colors according to an embodiment of the image forming body of the present invention. FIG. 6 is an enlarged schematic diagram illustrating two-change latent images that appear when the angle at which the verification tool is superimposed on one color is changed by 90 degrees in another embodiment of the image forming body of the present invention. It is an expansion schematic diagram explaining the case where the 2 change latent image shown in FIG. 2 is reproduced in the same location. FIG. 6 is an enlarged schematic diagram illustrating an image forming body in which two regions having different uniform halftone dot pitches exist in another embodiment of the image forming body of the present invention. It is a figure explaining the case where a 2 change latent image is put into 2 colors, cyan and magenta. It is a reference figure explaining the case where a 2 change latent image is put into four colors, cyan, magenta, yellow, and black.

Explanation of symbols

1 ... halftone dot (magenta)
2 ... halftone dot (cyan)
3 ... Verification tool (line film)
4 ... Verification tool (dot pattern film)
5. Latent image part (magenta)
6. Latent image part (cyan)
7 ... Visualized latent image (magenta)
8 ... Visualized latent image (cyan)
9 ... latent image part (primary)
10 ... latent image part (secondary)
11 ... Visualized latent image (primary)
12 ... Visualized latent image (secondary)
13... Region 13
14... Region 14
15 ... Visualized latent image (region 13)
16 ... Visualized latent image (region 14)

Claims (5)

An image forming body in which an image composed of a latent image portion and a non-latent image portion is formed on a substrate,
The non-latent image portion is composed of halftone dots having a uniform pitch, and the latent image portion is composed of halftone dots shifted by approximately ½ pitch with respect to the halftone dots of the non-latent image portion.   2. The image forming body according to claim 1, further comprising: a plurality of the latent image portions different in a direction in which the halftone dots are shifted by approximately ½ pitch with respect to the halftone dots of the non-latent image portion.   The image forming body according to claim 1, wherein the image is formed of halftone dots of different colors having different halftone dot angles.   4. The image forming body according to claim 1, wherein there are a plurality of regions having different pitches of halftone dots forming the image. 5.   The image forming body according to any one of claims 1 to 4, wherein at least one halftone dot is formed of fluorescent ink.