JP7437013B2 - Anti-counterfeiting form - Google Patents

Description

The present invention relates to counterfeit prevention forms used for securities, certificates, and the like.

Anti-counterfeiting forms are known to be used for securities, certificates, etc., on which are printed anti-counterfeiting images consisting of a latent image that becomes visible when copied using a copying machine and a background formed around the latent image. It is being As such a forgery prevention image, for example, Patent Document 1 proposes a configuration in which one of the background and the latent image is formed by halftone dots, and the other is formed by parallel lines. Further, as another configuration, a configuration in which both the background and the latent image are formed by halftone dots or parallel lines is also well known.

In such conventional configurations, the size of halftone dots and the line width of parallel lines are set so that one of the background and the latent image is reproduced in the copy and the other is not reproduced, and the latent image is difficult to see in the original. The interval between halftone dots and the pitch of lines are set.
For example, as shown in FIGS. 6 and 7, in a configuration in which the background 6 is formed by halftone dots 9 and the latent image 105 is formed by parallel lines 111, the size of the halftone dots 9 is made small and the interval between the halftone dots 9 is A background 6 with a narrow line width and a latent image 105 with a thicker line width and a wider pitch of the line lines 111 are formed. With this configuration, while the latent image 105 is difficult to see on the original 101, when it is copied, the background 6 is not reproduced and the parallel lines 111 of the latent image 105 are reproduced, so that the latent image 105 is clearly visible. appear. Thereby, the copied material (not shown) and the original document 101 can be easily distinguished.

Special Publication No. 1-5835

By the way, in the conventional configuration of FIGS. 6 and 7 in which the background 6 is formed by halftone dots 9 and the latent image 105 is formed by parallel lines 111, since the pitch of the parallel lines 111 is wide, the background 6 and the latent image are At the boundary with 105, a region with locally low concentration may occur. To be more specific, in the latent image 105 made up of parallel lines 111 in which a plurality of straight lines 112 are arranged in parallel, as described above, the line width of the straight lines 112 is made thicker and the pitch is made wider. The number of straight lines 112 is reduced. Therefore, in the latent image 105, when a gap 113 between the straight lines 112 forming the parallel lines 111 is placed at the boundary with the background 6, the density locally decreases due to the gap 113, resulting in light and shade (Fig. 7). In such a conventional configuration, when the latent image 105 on the original document 101 is looked at, the shading becomes noticeable, and there is a possibility that the latent image 105 may be visually recognized.
This problem similarly occurs in a configuration in which the background is formed by lines and the latent image is formed by halftone dots. Furthermore, even if both the background and the latent image are formed by parallel lines, the same problem can occur if one has a wider line width and pitch than the other.

The present invention proposes an anti-counterfeit form that can prevent the latent image from being visually recognized by suppressing the occurrence of shading at the boundary between the latent image and the background.

The present invention provides a printed anti-counterfeiting image that includes a background and a latent image that is made visible by copying, and that at least one of the background and the latent image is composed of lines arranged in parallel at a predetermined pitch. In the anti-counterfeit form, one of the background and the latent image constituted by the parallel lines is formed by a rectangular unit drawing section provided along one direction, and a rectangular unit drawing section provided along one direction, and a rectangular unit drawing section provided along one direction, and a rectangular unit drawing section extending along the longitudinal direction of the unit drawing section. and a drawing line drawn in a unit drawing section, and is composed of a plurality of unit image blocks arranged in parallel in the width direction of the unit drawing section, and the line is formed by the drawing line of each unit image block. This is an anti-counterfeit form that is characterized by the fact that it has been authenticated.
Here, the unit image block includes a unit drawing section and a drawing line, and one of the background and the latent image is formed by a plurality of unit image blocks arranged in parallel in the width direction of the unit drawing section. It is something. Further, as the drawing line, a solid line, a broken line, a chain line (one-dot chain line, two-dot chain line, etc.), and a dotted line are preferably used. The drawing line is not limited to a straight line, but may be a wavy line or a broken line.

In this configuration, since the unit image block is a drawing line drawn in the longitudinal direction of the unit drawing section, one of the background and the latent image constituted by the unit image block is The unit image blocks have the same density, and the entire area is formed with uniform density. The one unit image block composed of a plurality of unit image blocks has the same density as the unit image block arranged at the boundary part with the other unit image block, so that the boundary part and the other unit image block have the same density. portions are formed at approximately the same concentration. Therefore, according to the configuration of the present invention, it is possible to suppress the occurrence of local shading at the boundary between the background and the latent image in the conventional configuration described above, and the latent image is visually recognized due to this local shading. This can be prevented.

In the forgery prevention form of the present invention described above, a configuration is proposed in which the unit image block is formed by drawing a drawing line in the center of the unit drawing section in the lateral direction.

In such a configuration, since the drawing line is drawn at the center in the transverse direction of the unit drawing section, the drawing line is biased to one side in the transverse direction in the unit image block arranged at the boundary part. It will not be installed. Thereby, the above-mentioned effect of the present invention of suppressing the occurrence of local shading at the boundary between the background and the latent image can be further improved.

As described above, in the anti-counterfeit form of the present invention, one of the background and the latent image formed by parallel lines is formed by a short unit image block in which drawing lines are drawn in the longitudinal direction of a rectangular unit drawing section. Since a plurality of them are arranged side by side in the hand direction, it is possible to suppress the occurrence of local shading at the boundary with the other. Therefore, according to the configuration of the present invention, it is possible to solve the above-mentioned problem of the conventional configuration in which the latent image is visually recognized due to the shading that occurs at the boundary between the latent image and the background.

FIG. 2 is an explanatory diagram showing a counterfeit prevention form 1. FIG. FIG. 5 is an explanatory diagram showing an enlarged part of the latent image 5. FIG. 3 is an enlarged view of the X section in FIG. 2. FIG. 5 is an explanatory diagram showing a unit image block 15 forming a latent image 5. FIG. FIG. 5 is an explanatory diagram showing a copy 51 obtained by copying the anti-counterfeit form 1; FIG. 2 is an explanatory diagram showing a counterfeit prevention form 101 with a conventional configuration. FIG. 2 is an explanatory diagram showing an enlarged part of a latent image 105 of a conventional configuration.

Embodiments according to the present invention will be described below with reference to the accompanying drawings.
FIG. 1 shows a counterfeit prevention form 1 according to an embodiment. On this anti-counterfeit form 1, an anti-counterfeit image 2 is printed over the entire paper surface. Such anti-counterfeiting form 1 is used for securities, certificates, etc., for example.

As shown in FIGS. 1 and 2, the anti-counterfeiting image 2 is composed of a latent image 5 consisting of the characters "COPY" and a background 6 around the latent image 5. A latent image 5 is formed by parallel lines 11, and a background 6 is formed by halftone dots 9.

Here, the halftone dots 9 constituting the background 6 are, as shown in FIG. and the interval.
On the other hand, the parallel lines 11 constituting the latent image 5 are, as shown in FIG. The pitch is set based on the pitch. In this embodiment, the straight line 12 is a solid line, and the straight line 12 corresponds to the drawing line according to the present invention.

The anti-counterfeiting image 2 includes the size and interval of the dot circles 9a constituting the halftone dots 9, and the size and spacing of the dot circles 9a constituting the halftone dots 9, so that the latent image 5 is difficult to visually recognize and only the latent image 5 is reproduced when copied by a copying machine. The line width and pitch of the straight lines 12 constituting the parallel lines 11 are respectively set. That is, the background 6 is formed by arranging a large number of dotted circles 9a with relatively small diameters in the vertical and horizontal directions at relatively narrow intervals. The latent image 5 is formed by straight lines 12 having a line width wider than the diameter of the dotted circle 9a arranged in parallel at a pitch wider than the interval between the backgrounds 6.
In this embodiment, the parallel lines 11 are provided along a direction at a predetermined angle (for example, 15 degrees) when characters of a latent image 5 to be described later are viewed from the front.

In the forgery prevention image 2 having such a configuration, the latent image 5 and the background 6 are made to have approximately the same density when viewed visually, so that the latent image 5 is difficult to be visually recognized. When the background 6 is copied by a general copying machine, the dot circles 9a constituting the halftone dots 9 of the background 6 have an extremely small diameter, so they are difficult to detect by scanning by the copying machine, and the background 6 is reproduced. cannot be expressed (not expressed at all or expressed indistinctly). On the other hand, the latent image 5 is easily detected by scanning by a copying machine because the straight line 12 of the parallel lines 11 has a thicker line width than the diameter of the dotted circle 9a. As a result, the parallel lines 11 are reproduced, and the latent image 5 is clearly expressed. When the anti-counterfeit form 1 is copied using a copying machine in this way, a copy background 56 in which the halftone dots 9 are not reproduced and a copy image 55 in which the parallel lines 11 are clearly reproduced are expressed, as shown in FIG. A copy 51 is generated, and the copy image 55 of the characters "COPY", which reproduces the latent image 5, is made visible.

Next, main parts of the present invention will be explained.
As shown in FIG. 4, the latent image 5 is composed of a plurality of rectangular unit image blocks 15 arranged along one direction (the predetermined angular direction of the parallel lines 11) arranged in a direction orthogonal to the one direction. It was formed by the establishment of The unit image block 15 is composed of a rectangular unit drawing section 16 along the one direction, and one of the straight lines 12 drawn on the unit drawing section 16, and the straight line 12 is arranged along the one direction. is drawn along. Each unit image block 15 (unit drawing unit 16) constituting the latent image 5 has a length in the longitudinal direction set to various values according to the shape of the latent image 5, while a length in the transverse direction is the same ( or approximately the same). That is, each unit image block 15 (unit drawing section 16) has a rectangular shape formed by various lengths in the longitudinal direction and lengths in the transverse direction that are the same (or substantially the same). Note that one direction is the longitudinal direction of the unit image block 15 and the unit drawing section 16, and the direction orthogonal to the one direction is the lateral direction of the unit image block 15 and the unit drawing section 16.

In this embodiment, the unit drawing section 16 is constituted by a rectangular area without an outline, and only the straight line 12 is printed within the area. This straight line 12 is printed at the center of the unit drawing section 16 in the lateral direction, extending in the longitudinal direction of the unit drawing section 16, and bisects the unit drawing section 16 in the lateral direction. Note that the regions on both sides of the straight line 12 in the lateral direction of the unit drawing section 16 are respectively referred to as non-drawing areas 17 and will be used in the following explanation.

Each character "COPY" in the latent image 5 is formed by arranging a plurality of unit image blocks 15 having different longitudinal lengths in parallel in the lateral direction, and the adjacent unit image blocks 15 The unit drawing units 16 are arranged side by side without any gaps. Then, an outline of each character is formed by both edges of the plurality of unit image blocks 15 constituting each character and side edges of adjacent unit drawing parts 16 that do not touch each other.

In each character of the latent image 5, the straight lines 12 of the plurality of unit image blocks 15 constituting each character are arranged in parallel to form the parallel lines 11, and the straight lines 12 of the adjacent unit image blocks 15 are arranged in parallel. The interval t is the pitch of the parallel lines 11. Between the adjacent straight lines 12, 12 of the line 11, two non-drawing areas 17, 17 are arranged with no gap in the transverse direction, and the interval t is the width of the non-drawing area 17 in the transverse direction. The length is twice the width plus the line width of the straight line 12 (in other words, it is equal to the width of the unit image block 15 in the lateral direction).
Here, as described above, the interval t is set according to the line width of the parallel lines 11 (straight lines 12) so that the latent image 5 and the background 6 have substantially the same density. The width in the width direction of the unit image block 15 is set by the width in the width direction of the non-drawing area 17 determined by this interval t and the line width of the straight line 12.

On the other hand, conventional configurations for comparison with the above-described embodiments are shown in FIGS. 6 and 7. The anti-counterfeit image 102 printed on the anti-counterfeit form 101 with the conventional configuration includes a latent image 105 consisting of the letters "COPY" similar to the above-mentioned embodiment, and a background 6 provided around the latent image 105. It is made up of. Here, in the forgery prevention image 102 having a conventional configuration, the background 6 is formed of halftone dots 9, and the size and interval of the dot circles 9a forming the halftone dots 9 are set as in the above-described embodiment. It is set. The latent image 105 is formed by parallel lines 111 as in the embodiment described above, and the line width and pitch (interval t) of the straight lines 112 constituting the parallel lines 111 are set in the same manner as in the embodiment. There is. As a result, the latent image 105 of the conventional configuration has approximately the same density as the latent image 5 of the embodiment described above, and the line width of the straight line 112 constituting the line 111 is thicker than the diameter of the dot circle 9a of the halftone dot 9. . This latent image 105 is formed by converting each character "COPY" into an outline using curved lines or straight lines of the same color or transparent color as the paper surface, and printing the parallel lines 111 inside the outline. Note that, similarly to the embodiment, the parallel lines 111 are provided along a direction at a predetermined angle (for example, 15 degrees) when the latent image 105 is viewed from the front.

Comparing the anti-counterfeiting form 1 of the embodiment and the anti-counterfeiting form 101 of the conventional configuration, it is found that in both cases, the latent images 5, 105 constituting the anti-counterfeiting images 2, 102 and the background 6 have approximately the same density visually. Therefore, when viewed from above, the latent images 5, 105 are inconspicuous and provide a desired camouflage effect. Furthermore, when these counterfeit prevention forms 1, 101 are copied using a general copying machine, the halftone dots 9 of the background 6 are not reproduced and the lines 11, 111 of the latent image 5, 105 are clearly shown in each copy. The latent image 5, 105 is made visible (see FIG. 5). This is because the dot circles 9a of the halftone dots 9 that make up the background 6 have an extremely small diameter, while the straight lines 12, 112 of the parallel lines 11, 111 that make up the latent images 5, 105 have thick line widths. This is because the straight line 12 is easy to detect and the point circle 9a is difficult to detect when the machine scans. These copies can be easily distinguished from the originals. Therefore, both of the anti-forgery forms 1 and 101 can be prevented from being forged by a copying machine.
On the other hand, in the forgery prevention image 102 of the conventional configuration, as shown in FIG. Low density portions (for example, portions of "C", "P", and "Y") may occur. That is, the width of the gap 113 arranged at the boundary portion is the distance t at the maximum, and as the width approaches the distance t, the concentration of the boundary portion decreases. If a gap 113 having a width substantially the same as the interval t is provided at this boundary portion, the shading will appear relatively clearly. When such an anti-counterfeit image 102 is watched, there is a possibility that a boundary portion with locally low density will stand out due to the difference in shading from the surrounding area, and the latent image 105 may be visually recognized. As described above, this conventional configuration has a problem in that the camouflage effect is reduced due to the shading that occurs at the boundary portion.
On the other hand, since the anti-counterfeiting image 2 of the embodiment is formed by arranging a plurality of unit image blocks 15 in parallel in the lateral direction as described above, the background image 2 as shown in FIGS. A unit image block 15 is arranged at the boundary between the latent image 6 and the latent image 5. Although the unit image blocks 15 have different lengths in the longitudinal direction, the line widths of the straight lines 12 and the widths of the unit drawing portions 16 in the lateral direction are the same, so they all have the same density. Therefore, no local shading occurs at the boundary portion. To be more specific, since the unit image block 15 of this embodiment has a straight line 12 drawn at the center in the transverse direction, no matter where the unit image block 15 is placed on the boundary, the relationship between the straight line 12 and the boundary is The interval is constant (=width of non-drawing area 17=t/2). Thereby, it is possible to stably prevent a reduction in density at the boundary portion, and to prevent the occurrence of local shading. Therefore, according to the configuration of this embodiment, even when the anti-counterfeit image 2 is watched, the boundary between the latent image 5 and the background 6 can be prevented from becoming conspicuous, and the desired camouflage effect can be stably achieved. can be demonstrated.

As described above, the configuration of this embodiment can suppress the occurrence of shading at the boundary portion of the latent image 5, and therefore can suppress the latent image 5 from being visually recognized when the anti-counterfeit image 2 is gazed at. It has an effect. Furthermore, as a matter of course, the anti-counterfeiting form 1 has a camouflage effect that makes the latent image 5 less noticeable when the anti-counterfeiting image 2 is viewed from above, and anti-counterfeiting by making the latent image 5 visible in the copied material. play the effect

The present invention is not limited to the embodiments described above, and it is possible to implement configurations other than the embodiments described above with appropriate changes within the scope of the spirit of the present invention.

For example, in the above-mentioned embodiment, the parallel lines 11 are configured by straight lines 12, but the parallel lines are not limited to this, and the parallel lines can also be configured by broken lines, dashed lines, dotted lines, or the like. Furthermore, it is also possible to use a wavy line or a broken line. Note that even in the case of configuring with wavy lines or polygonal lines, these wavy lines etc. are formed along the longitudinal direction of the unit drawing section.

Further, in the above embodiment, the latent image 5 is formed by a plurality of unit image blocks 15 and the background 6 is formed by halftone dots 9, but the present invention is not limited to this. For example, the latent image can be formed by halftone dots. However, it is also possible to configure the background with the unit image blocks. Alternatively, as in the embodiment, the latent image may be formed by unit image blocks, and the background may be formed by parallel lines. In this configuration, the parallel lines of the background are formed with different line widths, pitches, and angles from the parallel lines of the latent image. Furthermore, it is also possible to form the background by the unit image blocks and form the latent image by parallel lines set to different line widths, pitches, and angles from the background.

Further, in the above-mentioned embodiment, the unit image block 15 constituting the latent image 5 has a configuration in which the straight line 12 is disposed at the center of the unit drawing section 16 in the lateral direction. It is also possible to arrange it near one edge of the drawing section 16.
Furthermore, it is also possible to adopt a configuration in which a plurality of straight lines are arranged in each unit drawing section. In this case, each straight line may be arranged so that the unit drawing section 16 is divided into equal widths in the lateral direction by a plurality of straight lines. For example, the unit drawing section can be divided into three equal parts in the lateral direction by two straight lines. Further, it is also possible to adopt a configuration in which a double line is arranged in the unit drawing section.

Further, in the above embodiment, the unit image blocks 15 are arranged in parallel so that the longitudinal direction of the unit image blocks 15 is along a direction of 15 degrees when the character of the latent image 5 is viewed from the front. However, the present invention is not limited to this, and the longitudinal direction of the unit image block 15 can be changed as appropriate. For example, the unit image blocks 15 may be arranged in parallel so that the longitudinal direction of the unit image blocks 15 is along a 45 degree direction or a 60 degree direction when viewed from the front, or the longitudinal direction of the unit image blocks 15 may be arranged in parallel. The unit image blocks 15 may be arranged in parallel along the vertical or horizontal direction.

Further, in the above-described embodiments, the line width and pitch of the parallel lines forming the latent image can be changed and set as appropriate. Furthermore, the density of the latent image and the background can also be changed and set as appropriate. By setting the density of the latent image and the background, it is also possible to variously change the manner in which the latent image and the background are expressed in a copy. For example, the density of the latent image and the background may be set so that there is a relatively large difference in density between the image in which the latent image is reproduced and the image in which the background is reproduced in the copied material.

Further, in the above-described embodiment, the anti-forgery image 2 is printed on the entire paper surface of the anti-forgery form 1, but the invention is not limited to this, and the anti-forgery image may be printed on a part of the paper surface. Also good.

1 Anti-counterfeiting form 2 Anti-counterfeiting image 5 Latent image 6 Background 9 Halftone dots 110,000 lines 12 Straight line (image line)
15 Unit image block 16 Unit drawing section

Claims (1)

An anti-counterfeiting device printed with an anti-counterfeiting image comprising a background and a latent image made visible by copying, and at least one of the background and the latent image is composed of lines arranged in parallel at a predetermined pitch. In the ledger,
One of the background and the latent image constituted by the parallel lines,
It includes a rectangular unit drawing section provided along one direction, and drawing lines drawn on the unit drawing section extending in the longitudinal direction of the unit drawing section, and drawing lines arranged in the short direction of the unit drawing section. It is composed of multiple unit image blocks set up,
The line is constituted by the drawing lines of each unit image block,
Furthermore, each unit image block is formed by drawing a drawing line in the center of the unit drawing section in the lateral direction .