JP6564197B2 - Anti-counterfeiting form - Google Patents

Description

  The present invention relates to a forgery prevention form used for securities and certificates.

  Securities, certificates, and the like are generally printed with a background pattern or a color pattern on the background. For example, a line pattern arranged at a predetermined interval, a pattern in which a plurality of polygons or circles are arranged, and the like are known as such a background pattern and a chromatic pattern. Such a background pattern or a color pattern is not only a background design for securities and certificates, but also has a function to prevent forgery by a copying machine or the like. That is, when printing is performed by a copying machine, a so-called moiré image is generated due to a tint block pattern, a coloring pattern, or the like. Therefore, it is possible to determine whether the moiré image is a copy, and to prevent forgery by the copying machine. Here, the moiré image is an interference fringe generated when a line drawing such as a straight line or a curve constituting the above-described background pattern or chromatic pattern interferes with the scanning direction of the light irradiated by the copying machine.

  For example, Patent Document 1 has been proposed as a form applied to securities and certificates. In such a configuration, a line pattern in which a plurality of wavy lines are arranged at predetermined intervals is printed as a background.

Japanese Patent Laid-Open No. 11-32169

  By the way, if a background image such as a tint block or a color pattern is carefully observed, the form of a line drawing constituting the tint block or the color pattern can be visually recognized. For this reason, if the image pattern (structure) constituting the background image is relatively simple, the pattern can be easily obtained and there is a possibility that the pattern is forged relatively easily. For example, in the case of the above-described line pattern, a pattern in which a plurality of polygons or circles are arranged, etc., the straight lines and wavy lines constituting the lines and their intervals, or the size of the polygons and circles, etc. The structure is known relatively easily. And if the structure of the background image is known, it becomes possible to forge relatively easily based on this, so that the effect of preventing the forgery is reduced. Therefore, there is a demand for a configuration that makes it difficult to accurately know the structure of the background image even if the background image is visually recognized.

  The present invention is applied to securities, certificates, and the like, and provides a forgery prevention form that can suppress the acquisition of the structure of the background image as much as possible and improve the forgery prevention effect. It is what we propose.

  The present invention includes an information description area in which desired information is described on a paper surface, and a background image for preventing forgery is printed at least in the information description area. A straight line and / or a curve is constituted by a plurality of non-closed graphic elements that are regularly arranged so as not to form a closed region bounded by the line, and the non-closed graphic elements are continuous in a single stroke. It is a forgery prevention form characterized by comprising one or a plurality of continuous diagrams.

  Here, it is preferable that the continuous diagram is a region in which a background image is printed, and a plurality of non-closed graphic elements constituting the continuous diagram are substantially evenly continuous. Further, the background image may have a configuration including only a continuous diagram, or may include a configuration including not only a continuous diagram but also one or a plurality of secondary diagrams different from the continuous diagram. Further, in a configuration having a plurality of continuous diagrams, a configuration in which each continuous diagram is not in contact with each other is preferable, and in a configuration having a continuous diagram and a secondary diagram, each diagram is A configuration in which they are not in contact with each other is preferable. In addition, a configuration in which a region for printing a background image is filled with the background image is preferable.

  In such a configuration, the continuous diagram is formed of a plurality of non-closed graphic elements that do not form a closed region in a single stroke, and has a relatively complicated structure. Then, the non-closed graphic element regularly continues a straight line or / a curved line, so that a one-stroke continuous line diagram can be formed relatively easily and stably. By providing a continuous diagram of such a complicated structure in the background image, even if the continuous diagram is visually recognized for counterfeiting or the like, it is difficult to accurately know the structure of the continuous diagram. For this reason, the configuration of the present invention is difficult to accurately duplicate the same background image as compared to the above-described conventional simple pattern such as a line pattern or a pattern in which polygons are arranged. Therefore, according to the structure of this invention, it can suppress as much as possible that the structure of a continuous diagram is acquired, and the effect of preventing forgery improves.

  In the continuous diagram, the non-closed graphic element does not form a closed region. Therefore, the non-closed graphic element is constituted by a plurality of straight lines and / or curved lines such as vertical and horizontal directions and diagonal directions of the drawing. For this reason, during copying by the copying machine, each line direction of the non-closed graphic element and the scanning direction of the light emitted from the copying machine interfere with each other, and interference fringes (moire) are likely to occur. Due to the interference fringes, the configuration of the present invention is highly effective in preventing forgery by copying.

  In the forgery prevention form according to the present invention described above, a configuration is proposed in which the one-stroke continuous diagram is formed by a recursive curve. Here, as the recursive curve, for example, a Hilbert curve, a Gospar curve, a Koch curve, a Sherpinski curve, a Moore curve, a Lebak curve, and the like are preferably used. In the configuration including a plurality of continuous diagrams, the same recursive curve may be used, or different types of recursive curves may be used.

  In such a configuration, since the continuous diagram is a recursive curve formed by a rule for performing recursive processing (hereinafter referred to as a conversion rule), it is formed according to the regularity of the conversion rule. Such a continuous diagram is a complex structure that is non-contact except at least at the start and end points. Therefore, according to this structure, the forgery prevention effect mentioned above can be improved further. Further, since the continuous diagram is formed according to the conversion rule as described above, it can be set relatively easily according to the application of the form on which the background image is printed, and is accurate and stable according to the conversion rule. This makes it possible to print with high productivity.

  In the forgery prevention form of the present invention described above, the background image includes a plurality of continuous lines drawn in a single stroke, and at least one of the continuous lines is a recursive curve. A configuration is proposed in which at least one other continuous diagram is formed by parallel continuous lines that are continuous with the recursive curve at a predetermined interval. Here, as the recursive curve, for example, a Hilbert curve, a Gosper curve, a Koch curve, a Sherpinski curve, a Moore curve, a Lebak curve, and the like are preferably used as in the above configuration.

  In such a configuration, as described above, the recursive curve according to the conversion rule has a complicated structure that is non-contact except at least at the start point and the end point, and thus the forgery prevention effect can be improved. Further, since the parallel continuous lines are formed side by side with the recursive curve at a predetermined interval, a pseudo recursive curve is formed. Therefore, a parallel continuous line is also a complicated structure like a recursive curve, and exhibits the forgery prevention effect. Therefore, according to this structure, the forgery prevention effect concerning this invention mentioned above can be improved further. Furthermore, the recursive curve can be easily set as described above, and can be printed accurately and stably. A parallel continuous line parallel to the recursive curve can be set and printed in the same manner. Therefore, even in this configuration, the productivity is excellent.

  In the forgery-preventing form of the present invention described above, a one-stroke-shaped continuous diagram is formed with a missing line portion in which a straight line and / or a curve constituting the continuous diagram is partially disconnected at a predetermined portion. A configuration is proposed.

  According to such a configuration, since the missing line portion is provided, it is more difficult to accurately obtain the structure of the continuous diagram. Therefore, the forgery prevention effect of the present invention described above can be further improved.

  In the forgery prevention form of the present invention described above, a configuration is proposed in which the density of the background image is 5% or more and 50% or less in the region where the background image is printed.

  In such a configuration, if the density of the background image is 5% or more, the effect of hardly knowing the structure of the continuous diagram is sufficiently exhibited, while the density of the background image is 50% or less. For example, the structure of the continuous diagram can be sufficiently identified. Therefore, according to the present configuration, the above-described operational effect of the present invention that improves the forgery prevention effect can be properly exhibited.

  Note that the density of the background image is preferably 10% or more, and this makes it possible to more fully exhibit the effect that it is difficult to know the structure of the continuous diagram described above. Further, the density of the background image is preferably 30% or less, whereby the structure of the continuous diagram can be identified more clearly.

  As described above, the forgery-preventing form of the present invention comprises a plurality of non-closed graphic elements in which a straight line and / or a curved line are continuously arranged in a single stroke in a background image printed on a paper surface. Since the continuous diagram is provided, even if the continuous diagram of the background image is visually recognized for counterfeiting or the like, it is difficult to accurately know the structure of the continuous diagram. Therefore, according to the configuration of the present invention, the forgery prevention effect can be improved.

1 is a plan view of a forgery prevention form 1 of Example 1. FIG. It is the X section enlarged view in FIG. It is explanatory drawing which shows only the recursive curve 12 in the background image 11. FIG. It is explanatory drawing which decomposes | disassembles and represents the background image. 6 is a plan view of a forgery prevention form 31 according to Embodiment 2. FIG. It is the Y section enlarged view in FIG. It is explanatory drawing which shows only the recursive curve 33 in the background image 32. FIG. It is explanatory drawing which decomposes | disassembles and represents the background image. FIG. 10 is a plan view of a forgery prevention form 51 according to a third embodiment. It is the Z section enlarged view in FIG. It is explanatory drawing which shows only the recursive curve 53 in the background image 52. FIG. It is explanatory drawing which decomposes | disassembles and represents the background image. FIG. 10 is a plan view of a forgery prevention form 81 according to a fourth embodiment.

  Embodiments according to the present invention will be described according to the following Examples 1 to 4.

  FIG. 1 is a plan view showing an outline of a forgery prevention form 1 according to the first embodiment, and FIG. 2 is an explanatory view showing a background image 11 printed on the forgery prevention form 1. Here, the forgery prevention form 1 is suitably used for securities, certificates, and the like, and has an information description column 5 in which desired information is written on the surface. The information description field 5 constitutes an information description area according to the present invention.

The background image 11 is composed of one recursive curve 12 and a plurality of parallel continuous lines 13. As shown in FIG. 3A, the recursive curve 12 is formed according to the following conversion rule (1), and is a so-called Hilbert curve.
L = −RF + LFL + FR−, R = + LF−RFR−FL + (1)
Here, the tilt angle is “90 degrees”, and the initial value is “R”.

  Here, as the Hilbert curve of the recursive curve 12, a plurality of non-closed graphic elements 21 in which straight lines in the vertical direction and the horizontal direction are continuous are formed in a single stroke. And in the area 7 where the background image 11 is printed, the entire area 7 is drawn substantially evenly. More specifically, in the Hilbert curve of the present embodiment, a straight line is drawn in the vertical direction (or horizontal direction), a straight line is drawn in the horizontal direction (or vertical direction) inclined by 90 degrees from the end, and 90 degrees from the end. It is formed by repeatedly drawing a straight line in the vertical direction and a straight line in the horizontal direction so that a straight line is drawn in the vertical direction (or horizontal direction) inclined. Then, the direction of tilting by 90 degrees is set so that the straight lines do not intersect with each other except at the start and end of the straight lines. Thus, in the Hilbert curve, the non-closed graphic elements 21 constituting the Hilbert curve have a shape (a U-shape) that does not form a closed region with the straight line as a boundary. The Hilbert curve is drawn so as not to intersect from the start point to the end point so that a closed region with the straight line as a boundary is not formed.

  The parallel continuous line 13 is a continuous line of a vertical line and a horizontal line drawn at a predetermined interval from the recursive curve 12, and each of these straight lines is adjacent to the recursive line. Each of them is parallel to the straight line of the curve 12. In the first embodiment, two parallel continuous lines 13 are drawn on each of the inner and outer sides of the recursive curve 12, and the background image 11 is composed of one recursive curve 12 and four parallel continuous lines 13. Has been. The recursive curve 12 and the four parallel continuous lines 13 are all substantially equal in distance between adjacent lines and are not in contact with each other. Thereby, in the area 7 on which the background image 11 is printed, the background image 11 is drawn over the entire area 7, and the density of the background image 11 is substantially leveled. Specifically, the width and interval of each straight line of the recursive curve 12 and the parallel continuous line 13 are set so that the density of the background image 11 is about 20%.

  As described above, the Hilbert curve of the recursive curve 12 is drawn according to the conversion rule (1). In other words, the Hilbert curve is a regular series of vertical and horizontal straight lines. Further, since the parallel continuous line 13 is drawn in parallel with the recursive curve 12, a U-shaped non-closed graphic element 26 drawn in parallel with the non-closed graphic element 21 of the recursive curve 12 is drawn with a single stroke. In other words, the straight lines in the vertical direction and the horizontal direction are regularly continuous so as to be parallel to the recursive curve 12.

  The region 7 on which the background image 11 is printed has a substantially rectangular shape and includes the information description column 5 described above. That is, the background image 11 is printed so as to fill the entire information description column 5. In the first embodiment, the recursive curve 12 and a plurality of parallel continuous lines 13 constitute a continuous diagram of the present invention.

  Further, in the first embodiment, a missing line portion 15 in which a straight line constituting the recursive curve 12 is partially broken is formed at a predetermined portion of the recursive curve 12. A plurality of missing line portions 15 are provided, and their positions are set in advance. In the first embodiment, missing line portions 15 and 15 are respectively formed at the upper right position and the lower left position in the information description column 5.

  In the configuration of the first embodiment described above, the recursive curve 12 that constitutes the background image 11 is a one-stroke Hilbert curve that does not intersect from the start point to the end point and has a relatively complicated form. is there. And since the parallel continuous line 13 which comprises the background image 11 is parallel to the recursive curve 12, it is a comparatively complicated form similarly to this recursive curve 12. FIG. For this reason, the background image 11 has a relatively complicated structure due to the recursive curve 12 and the parallel continuous line 13, so that it is difficult to accurately know the structure even when viewed for counterfeiting or the like. . Furthermore, the fact that the density of the region 7 of the background image 11 is set as described above also enhances the effect that it is difficult to learn the structure described above. By printing such a background image 11, even when the background image 11 is visually recognized due to forgery or the like, it is possible to suppress as much as possible the accurate acquisition of the structure of the background image 11. Therefore, the effect of preventing counterfeiting is dramatically improved. Moreover, since the above-described missing line portions 15 and 15 are formed in the recursive curve 12, and it is difficult to know this accurately, the effect of preventing forgery is further improved. In addition, according to such a configuration, for example, even when forgery in which information different from the original information is cut and pasted in the information description column 5 described above, the background image 11 of the information description column 5 is accurately duplicated. Is extremely difficult, so that the counterfeit can be found relatively easily and reliably.

  Further, since the recursive curve 12 and the parallel continuous line 13 are composed of straight lines in the vertical direction and the horizontal direction as described above, when copying with a copying machine, the recursive curve 12 and the parallel continuous line 13 are compared with the scanning direction of the light of the copying machine. Interference fringes (moire) are likely to occur due to interference. Therefore, the effect of preventing forgery by the copying machine is also improved.

  Furthermore, since the recursive curve 12 is a Hilbert curve according to the conversion rule (1), various settings can be changed according to the use of the form. For example, the size of the region 7 of the background image 11 can be changed or the density of the region 7 can be changed by appropriately setting the dimensions of the straight lines in the vertical direction and the horizontal direction. Such size change and density change can also be performed by changing the distance from the parallel continuous line 13.

  The second embodiment is a forgery prevention form 31 in which the background image 32 includes a recursive curve 33 composed of a Sherpinski curve and a plurality of parallel continuous lines 34 parallel to the recursive curve 33. In the second embodiment, since the configuration is the same as in the first embodiment except that the background image 32 is different, the same components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

  The region 47 on which the background image 32 is printed has a substantially rhombus shape, and the background image 32 is printed so as to fill the entire information description column 5.

The recursive curve 33 constituting the background image 32 is a Sherpinski curve formed according to the following conversion rule (2).
L = + R−F−R +, R = −L + F + L− (2)
Here, the tilt angle is “45 degrees”, and the initial value is “L−F−L−F”.

  Here, as the Sherpinski curve, a plurality of non-closed graphic elements 41 in which straight lines in the vertical direction, the horizontal direction, and the diagonal direction are continuous are formed in a single stroke. More specifically, the shellpinski curve of the second embodiment includes a vertical (or horizontal) straight line, a horizontal (or vertical) straight line inclined 90 degrees from the end, and a vertical (or horizontal) direction. ) And a straight line in an oblique direction inclined by +45 degrees or −45 degrees from the end of the straight line. Thereby, the Sherpinski curves intersect only at the start point and the end point, and do not intersect between the start point and the end point. That is, in the non-closed graphic element 41 constituting this Sherpinski curve, a closed region having the straight line as a boundary is not formed.

  On the other hand, the parallel continuous line 34 is a continuous line of a vertical line, a horizontal line and an oblique line drawn with a predetermined interval from the recursive curve 33. , Which are parallel to the adjacent straight line of the recursive curve 33. In the second embodiment, one such parallel continuous line 34 is drawn outside the recursive curve 33 and two inside. Furthermore, a plurality of (for example, four) secondary continuous lines 35 having portions parallel to the parallel continuous lines 34 are drawn on the outer side of the outer parallel continuous lines 34, and the inner parallel continuous lines 34 are drawn. A plurality of polygonal secondary closing lines 36 (for example, three or four depending on the place to be drawn) forming a closed region are drawn further inside. Here, the secondary continuous line 35 and the secondary closed line 36 are drawn so as to fill an area 47 of the background image 32 where the recursive curve 33 and the plurality of parallel continuous lines 34 are not drawn, They are not in contact with each other and are not in contact with the recursive curve 33 and the parallel continuous line 34.

  The shellpinsky curve of the recursive curve 33 is a continuous line of vertical, horizontal, and diagonal directions according to the conversion rule (2), and the non-closed graphic element 41 is drawn in a single stroke. It consists of a plurality of consecutive. In addition, the parallel continuous line 34 is formed by a plurality of non-closed graphic elements 42 drawn in parallel with the non-closed graphic elements 41 constituting the recursive curve 33 in a single stroke. The straight lines in the direction, the horizontal direction, and the diagonal direction are regularly continuous so as to be parallel to the recursive curve 33.

  Also in the second embodiment, in the region 47 where the background image 32 is printed, the background image 32 is drawn over the entire region 47, and the density of the background image 32 is substantially leveled. ing. The recursive curve 33, the parallel continuous line 34, the secondary continuous line 35, and the secondary closed line 36 are drawn so that the density of the background image 32 is about 20%. In the second embodiment, the recursive curve 33 and the parallel continuous line 34 constitute a continuous diagram according to the present invention, and the secondary continuous line 35 and the secondary closed line 36 are so-called. A secondary diagram is constructed.

  Even in the second embodiment, the missing line portion 45 is formed at a predetermined portion of the recursive curve 33. Specifically, in the information description column 5, missing line portions 45 and 45 are formed at two locations, a central upper position and a central lower position, respectively.

  In the configuration of the second embodiment described above, the recursive curve 33 is a one-stroke shellpinski curve, which does not intersect except at the start point and the end point and has a relatively complicated form. The background image 32 has a parallel continuous line 34, a secondary continuous line 35, and a secondary closed line 36 in addition to the recursive curve 33, and thus has a more complicated structure. For this reason, it is difficult to accurately obtain the structure even when it is visually recognized. Further, by setting the density of the background image 32, the effect of making it difficult to know the structure of the background image 32 is enhanced. For this reason, the configuration of the second embodiment can suppress as much as possible the accurate acquisition of the structure of the background image 32, and the effect of preventing counterfeiting is dramatically improved. Further, as in the first embodiment described above, the missing line portions 45 and 45 further improve the effect of preventing forgery.

  In addition, since the recursive curve 33, the parallel continuous line 34, the secondary continuous line 35, and the secondary closed line 36 are constituted by straight lines in the vertical direction, the horizontal direction, and the diagonal direction, copying by a copying machine is possible. Interference fringes (moire) are more likely to occur.

  Thus, even in the configuration of the second embodiment, the same operational effects as those of the first embodiment can be obtained.

  The third embodiment is an anti-counterfeit form 51 in which the background image 52 includes a recursive curve 53 composed of a Gospar curve and a plurality of parallel continuous lines 54 parallel to the recursive curve 53. The area 67 on which the background image 52 is printed has a shape similar to a hexagon, and the background image 52 is printed so as to fill the entire area of the information description column 5. In the third embodiment, since the configuration is the same as in the first embodiment except that the background image 52 is different, the same components are denoted by the same reference numerals, and the description thereof will be omitted as appropriate.

The recursive curve 53 is a Gospar curve formed according to the following conversion rule (3).
L = L + R ++ R−L−−LL−R +, R = −L + RR ++ R + L−L−R−R
... (3)
Here, the tilt angle is “60 degrees”, and the initial value is “R”.

  Here, as the Gosper curve, a plurality of non-closed graphic elements 61 in which straight lines in the horizontal direction and the oblique direction are continuous are continuously formed in a single stroke. More specifically, the Gospar curve of the third embodiment is formed by repeatedly drawing a straight line in the horizontal direction and a straight line in the oblique direction inclined by +60 degrees or −60 degrees. Thereby, the Gospar curve does not intersect between the start point and the end point. That is, the non-closed graphic element 61 has a shape that does not form a closed region with the straight line as a boundary, and the recursive curve 53 is generally drawn so that a closed region with the straight line as a boundary is not formed.

  On the other hand, the parallel continuous line 54 is formed by continuously connecting the recurrence curve 53 and a horizontal straight line and an oblique straight line drawn at a predetermined interval, and each of these straight lines is adjacent to the recursion line 54. Each of them is parallel to the straight line of the curve 53. In the third embodiment, one parallel continuous line 54 is drawn on each of the inner and outer sides of the recursive curve 53. Furthermore, a plurality of (for example, two) secondary continuous lines 55 having portions parallel to the parallel continuous lines 54 are drawn on the outer side of the outer parallel continuous lines 54, and the inner parallel continuous lines 54 are drawn. A plurality of secondary closing lines 56 forming a closed region are drawn on the further inside. Here, the secondary continuous line 55 and the secondary closed line 56 are drawn so as to fill an area 67 in the background image 52 where the recursive curve 53 and the plurality of parallel continuous lines 54 are not drawn, They are not in contact with each other and are not in contact with the recursive curve 53 and the parallel continuous line 54.

  The Gospar curve of the recursive curve 53 is a line in which horizontal and oblique straight lines are regularly continued according to the conversion rule (3), and a plurality of the above-mentioned non-closed graphic elements 61 are continuously formed in a single stroke. Is. In addition, the parallel continuous line 54 is a plurality of non-closed graphic elements 62 drawn in parallel with the non-closed graphic element 61 constituting the recursive curve 53. In other words, the horizontal continuous line 54 is a horizontal line. The straight lines in the direction and the oblique direction are regularly continuous so as to be parallel to the recursive curve 53.

  Also in the third embodiment, in the area 67 where the background image 52 is printed, the background image 52 is drawn over the entire area 67, and the density of the background image 52 is substantially leveled. ing. The recursive curve 53, the parallel continuous line 54, the secondary continuous line 55, and the secondary closed line 56 are drawn so that the density of the background image 52 is about 20%. In the third embodiment, the recursive curve 53 and the parallel continuous line 54 constitute a continuous diagram according to the present invention, and the secondary continuous line 55 and the secondary closed line 56 are so-called. A secondary diagram is constructed.

  Also in the third embodiment, the missing line portion 65 is formed at a predetermined portion of the recursive curve 53. Specifically, missing line portions 65 and 65 are respectively formed at the left and right positions in the information description column 5.

  In the configuration of the third embodiment described above, the recursive curve 53 is a one-stroke gospar curve that does not intersect from the start point to the end point and has a relatively complicated form. The background image 52 has a parallel continuous line 54, a secondary continuous line 55, and a secondary closed line 56 in addition to the recursive curve 53, and thus has a more complicated structure. Even if it is visually recognized, it is difficult to know the structure accurately. Further, the effect of making it difficult to know the structure of the background image 52 is enhanced by setting the density of the background image 52. For this reason, the configuration of the third embodiment can suppress as much as possible the accurate acquisition of the structure of the background image 52, and the effect of preventing counterfeiting is greatly improved. Further, as in the first embodiment, the missing line portions 65 and 65 further improve the effect of preventing forgery.

  Further, since the recursive curve 53, the parallel continuous line 54, the secondary continuous line 55, and the secondary closed line 56 are constituted by straight lines in the horizontal direction and the oblique direction, interference fringes ( Moire) is more likely to occur.

  Thus, even in the configuration of the third embodiment, the same operational effects as those of the first embodiment described above can be achieved.

  The fourth embodiment is a forgery prevention form 81 in which a latent image 91 is formed on a recursive curve 83 and a plurality of parallel continuous lines 84 constituting a background image 82. Here, the recursive curve 83 is a Hilbert curve according to the conversion rule (1) as in the above-described first embodiment, and the parallel continuous line 84 is the inside and outside of the recursive curve 83 as in the above-described first embodiment. It is drawn parallel to the recursive curve 83 on both sides. That is, the recursive curve 83 of the fourth embodiment is obtained by continuing the same non-closed graphic element 21 (see FIGS. 2 and 3) as the recursive curve 12 of the first embodiment in a single stroke, and the parallel continuous lines of the fourth embodiment. Reference numeral 84 denotes a non-closed graphic element 26 (see FIG. 2) that is the same as the parallel continuous line 13 of the first embodiment and is continuous in a single stroke.

  The background image 82 is a predetermined part of the recursive curve 83 and the parallel continuous line 84, and the width of the straight line constituting each is approximately twice that of the other part, and the darkness of the straight line Thinner about half of the area. In this way, the latent image 91 indicating the characters “double” is formed on the background image 82. Although the latent image 91 has a straight line width approximately doubled, the darkness of the straight line is approximately half, so it is difficult to notice visually. On the other hand, when copying with a copying machine, since the darkness of the straight line becomes clear, a latent image 91 of “duplicate” appears clearly on the copied paper.

  Since the configuration of the fourth embodiment is the same as that of the first embodiment except that the latent image 91 is formed, the same components are denoted by the same reference numerals, and the description thereof is omitted as appropriate.

  In the configuration of the fourth embodiment, in addition to the same effects as the first embodiment described above, the original and the copied one are clearly differentiated by the latent image 91 that appears when the image is copied by a copying machine. Therefore, the effect of preventing forgery by copying is further improved.

  In the configurations of the first to fourth embodiments described above, the background image has a single recursive curve. However, as another configuration, a configuration having a plurality of recursive curves may be used. Similarly, the number of parallel continuous lines can be set as appropriate. Moreover, it is also possible to add a secondary continuous line, a secondary closed line, etc. to the structure of Example 1, 4 similarly to Example 2, 3.

  In the configurations of Examples 1 to 4 described above, the density of the background image can be set as appropriate within a range of 5 to 50%. Also, the number of missing line portions can be changed, and the missing line portions may be formed as parallel continuous lines.

  In the configurations of the first to fourth embodiments described above, the background image is printed on a part of the paper surface, but the background image can also be printed on the entire paper surface.

  Even in the configurations of the second and third embodiments, a latent image can be formed as in the fourth embodiment.

  In this invention, it is not limited to the Example mentioned above, About the structure other than the above-mentioned Example, it can change and implement suitably within the range of the meaning of this invention.

1,31,51,81 Anti-counterfeiting form 5 Information description column (information description area)
11, 32, 52, 82 Background image 12, 33, 53, 83 Recursive curve (continuous diagram)
13, 34, 54, 84 Parallel continuous lines (continuous diagram)
15, 45, 65 Missing line portion 21, 26, 41, 42, 61, 62 Non-closed graphic element

Claims (3)

The paper is provided with an information description area in which desired information is described, and a background image for preventing forgery is printed at least in the information description area,
The background image is drawn over the entire information description area,
Multiple plurality of straight lines and / or curves, so as not to form a closed region for the該線the boundary, in which a plurality of non-closed figure element configured continuously regularly, formed by continuous single stroke manner comprising a continuous diagram,
Among a plurality of continuous diagrams, at least one continuous diagram is formed by a recursive curve drawn over the entire area of the information description area, and at least one other continuous diagram is constant with an adjacent recursive curve. A forgery-preventing form characterized by being formed by parallel continuous lines that are parallel to each other at intervals . It has a continuous diagram consisting of a recursive curve that forms a missing line part that partially cuts a straight line and / or a curved line with respect to a graphic that consists of a plurality of non-closed graphic elements in a single stroke. The forgery prevention form according to claim 1, wherein the forgery prevention form is provided. 3. The forgery prevention form according to claim 1 , wherein the density of the background image is not less than 5% and not more than 50% in the area where the background image is printed.

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