JP3268419B2 - Method for preparing copy-preventive pattern and printed matter thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a latent image which cannot be distinguished by the naked eye on a curvilinear aggregate pattern, and the latent image appears when printed by a copying machine in a printed matter which requires forgery or alteration prevention. And a printed matter thereof.

[0002]

2. Description of the Related Art Counterfeiting and falsification prevention are important factors in printed matter such as securities such as banknotes, stock certificates and bonds, various certificates and important documents. These countermeasures for counterfeiting and alteration of printed matter mainly use a method that uses a pattern that makes extensive use of geometric patterns for design, and if any means are applied to the printed matter, a latent image that can not be recognized visually will appear. There is such a method. Typical examples of the former include tint block, color pattern, and relief pattern, which are widely used in the design of securities prints, etc.Typical examples of the latter include latent image intaglio and color reproduction with a copying machine normally. There are functional inks, copy-proof images, etc. that are not applied. However, with the recent remarkable spread of color copying machines, there is a danger that crimes caused by forgery and falsification will increase, and the development of technology as a more effective countermeasure for forgery and falsification has been desired.

[0003] As countermeasures against forgery and alteration using the above-mentioned geometric pattern, there are a tint block, a colored pattern, a relief pattern and the like.
Basically, a pattern is constituted by a set of music objects having a constant image width. These patterns take into account the design properties of the printed matter, etc., can be counterfeited and prevent counterfeiting, making it difficult to produce the same pattern in a forged product by complicating the pattern, The role of counterfeiting prevention is enhanced by using colors that are difficult to reproduce with a plate making device or a copying machine, or by creating moiré for the scanning input and output of a copying machine and a scanner by making a complicated curved line. . In addition, the patterns are widely used worldwide in the design of securities prints and the like, and at the same time, have been used for a long time as prints having a monetary value such as banknotes, stock certificates, and bonds. It is an important pattern as a design that impresses luxury, securities such as banknotes, stock certificates, bonds, etc.
In the printed matter such as various certificates and important documents, the copy-forgery-inhibited pattern, the color pattern, the relief pattern and the like are indispensable in design. However, recently, with the advent of sophisticated photoengraving machines or copiers, sufficient forgery,
There is a disadvantage that it does not provide a falsification prevention effect.

[0004] When some means and action are applied to the printed matter, as a typical technique for producing a latent image which cannot be visually recognized, a copy protection image and a copy protection image are generally used. There is a series of techniques referred to. That is, the latent image applied to the printed matter appears by copying by the copying machine. In a printed material suitable for preventing forgery by such a copying machine, a latent image displaying characters composed of fine structural elements, for example, 85 lines and 30% halftone dots, is printed on the base paper surface using silver ink, and then printed. In a blank portion other than the latent image, coarser or denser than the latent image (for example, 150 lines 30)
%), And a printed matter containing a latent image suitable for preventing forgery by copying (Japanese Patent Application Laid-Open No. 57-20395). In addition, a latent image is printed with halftone dots on the surface of the paper, a background with the same density as the latent image is printed simultaneously with a line, and the decorative pattern on the top of the latent image including the background is light enough not to be reproduced by copying. By overprinting with a transparent ink, the surface of the printed matter is finished in a good appearance, and the pattern becomes invisible when copied.
A printed matter suitable for copy prevention (Japanese Patent Application Laid-Open No. Sho 60-7999), in which the background is reproduced and the latent image is not reproduced, and the density difference between the background and the latent image becomes obvious and it can be seen at a glance that the copy is a copy.
No. 1 gazette) and further has a latent image composed of halftone dots of 150 lines and 10%, and 50 to 60 dots on a white ground around the latent image.
Using a latent image plate having a background consisting of about 10% of lines, a deep color printing is performed on the surface of the paper, and a waveform pattern consisting of parallel lines forming a moire pattern when it interferes with the background lines. By applying a light-colored overprint that cannot be reproduced by a copier to the surface of the paper using an overprint plate equipped with a moiré pattern, a moiré pattern that distracts the naked eye is formed on the surface of the printed material. Since the latent image and the waveform pattern are not reproduced when the image is applied to a copying machine, only the background is reproduced. Therefore, the latent image is recognized separately from the background.
-87380) and the like.

[0005] In the printed matter disclosed in the above-mentioned publications and the like, a latent image is formed by the density of an image group (hereinafter referred to as a screen pattern) in which halftone dots or lines are continuously arranged at a fixed period, and the printed matter shown in FIG. As shown in 1), the pattern (2) on the entire printing surface is a screen pattern having a uniform density. When the printed matter (1) on which the latent image is applied is copied by a copying machine, the screen pattern (3) of the dense structure that is not reproduced and the screen pattern (4) of the rough structure that is reproduced are the copied matter of FIG. As shown in the pattern (2 ′) of the pattern (1 ′), a latent image of the screen pattern (3 ′) of the dense configuration that is not reproduced with respect to the screen pattern (4 ′) of the coarse configuration to be reproduced due to a density difference. The part is exposed so that it is obvious that it is a copy, but since the entire printed surface has a screen pattern with uniform density, the same printed surface can be seen with the naked eye. The above different screen patterns have a drawback that the presence of the latent image can be identified by the discrepancy due to the difference in screen shape and the interference part (5) with the boundary line of the latent image caused by the screen pattern. You. As a method for solving the above-mentioned drawbacks, all of the above publications and the like apply different patterns or light-colored transparent inks and light-colored overprints for cam-flagging the latent image, but the method is difficult to distinguish the latent image. Although this method is effective in that the number of steps is increased, it has a disadvantage that it is not economical.

Further, the inventors of the present invention disclose a latent image composed of a pattern such as a halftone dot or a line on the paper surface and a background around the latent image composed of a pattern different in density from the latent image.
In a printed matter printed simultaneously with colors, a latent image pattern on which the latent image is applied is not recognized by the naked eye. The printed matter suitable for copy prevention (Japanese Patent Application Laid-Open No. 4-170569) is used for cam-flagging the latent image. Other patterns, light-colored transparent inks, and even light-colored overprints without white circles or concentric circles that increase the dot percentage of the partial screen pattern relative to the entire screen pattern, etc. However, as described above, since all of the above-described conventional techniques apply a latent image by a screen pattern, the visual recognition of the latent image is easy. Since information such as written characters must play the role of a camouflage, it can be used only as a background pattern for documents, etc. , Or a single color print image line pattern itself subjected to the latent image on the free design of the pattern as Simon pattern, it is impossible to artistic prints with a decorative effect. Further, since the above-mentioned prior art methods must all be screen patterns composed of coarse and dense screens such as halftone dots or lines, securities such as banknotes, stock certificates, bonds, etc. that make heavy use of a tint block and a colorful pattern are used. There is a disadvantage that it is not suitable for use in existing products such as

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has been applied to various kinds of certificates and important documents requiring copy protection, as well as securities such as banknotes, stock certificates, and bonds. By applying a latent image, which is usually indistinguishable to the naked eye, to a curvilinear set pattern that can be applied, it does not require overprinting for cam flaring, and creates a copy protection pattern that has the effect of preventing forgery and falsification by a copying machine It is intended to provide a method and a printed material thereof.

[0008]

According to the present invention, a line drawing of a copy-preventing pattern comprises a line drawing of a portion where a latent image is not formed and a line drawing of a portion where a latent image is formed forming a curved aggregate pattern. Are arranged at regular intervals in the direction of the basic curve,
One object that is composed of fixed-period discontinuities consisting of objects of a predetermined shape with a constant object width in the direction perpendicular to the basic curve, and is continuous in the direction of the basic curve of the constant-period discontinuity of each part The length of one cycle consisting of the part and the non-image part is equal to each other,
Further, the image areas of the portions corresponding to the one period of the fixed-period discontinuity line of each portion are equal to each other. Further, a boundary line on the line drawing between the line drawing of the portion where the latent image is not applied and the line drawing of the portion where the latent image is applied is substantially perpendicular to the straight line tangent to the basic curve at the intersection of the basic curve and the outline of the latent image. The boundary line between the image area and the non-image area on the fixed-period discontinuity line of the part without the latent image and the part with the latent image, respectively, The straight line intersects a straight line that intersects at right angles with the straight line that contacts the basic curve at the intersection of the boundary between the drawing portion and the non-drawing portion.

[0009]

In a printed matter suitable for preventing forgery by a conventional copying machine, a latent image is formed by the density of a screen pattern such as halftone dots or lines, and the entire printed surface has a screen pattern having a uniform density. On the other hand, in the line drawing configuration of the present invention, a line drawing of a portion where a latent image is not formed and a line drawing of a portion where a latent image is formed to form a curved aggregate pattern are separated by a certain distance in the basic curve direction for each portion. Consists of fixed-period discontinuities consisting of objects of a predetermined shape with a constant image width in the direction perpendicular to the basic curve, arranged in the direction of the basic curve. The length of one cycle composed of one object part and the non-object part is equal to each other, and the image areas of the portions corresponding to the one cycle of the fixed-period discontinuity of each part are equal to each other. Copy protection pattern is composed That. That is, the line drawing of the portion where the latent image is not applied and the line drawing of the portion where the latent image is applied have the same image area as each other in the portion corresponding to the one cycle, and the printed matter on which the line drawing in which the expansion value and the like are added is printed. When observing the entire image, the observer will notice that the line drawing of the part where the latent image is applied and the line drawing of the part where the latent image is not applied are continuous in the direction of the basic curve, even though they are periodic breaks with different shapes. By recognizing the image as a single image, it is possible to make it impossible for the naked eye to identify the latent image at all. Also,
When a printed matter having the line drawing configuration of the present invention is copied by a copying machine, the fixed-period disconnection of the portion where the latent image is not applied is reproduced as it is, and the fixed-periodic disconnection of the portion where the latent image is applied is obtained from the resolution of the copier. When the copy is observed with the naked eye because it is not reproduced or the reproduction becomes defective, the line drawing of the part where the latent image is not applied is one continuous line in the direction of the basic curve despite the fact that it is a periodic break. Although it is recognized as an image line, the line image of the portion where the latent image is applied becomes unrecognizable, and a density difference occurs between the portion where the latent image is not applied and the portion where the latent image is applied, and the latent image appears. .

In addition, the boundary between the line drawing of the portion where the latent image is not applied and the line drawing of the portion where the latent image is applied is defined with respect to the straight line which is in contact with the basic curve at the intersection of the basic curve and the outline of the latent image. , And a straight line that intersects at a substantially right angle.In addition, the boundary line between the image area and the non-image area on the fixed-period discontinuity line of the part where the latent image is not applied and the part where the latent image is applied is defined as the basic curve and the fixed period. A straight line that intersects at a right angle with a straight line that is tangent to the basic curve at the intersection of the boundary between the image portion and the non-image portion on the broken line, and each boundary is formed according to the curve shape of the basic curve. Different angles can be given to the lines. Therefore, the boundary line between the line drawing of the portion where the latent image is not applied and the line drawing of the portion where the latent image is applied, and the image of the portion where the latent image is not applied and the portion where the latent image is applied on the fixed periodic discontinuity line The boundary line between the line part and the non-image part always changes depending on the curve shape of the copy protection pattern regardless of the outline of the latent image, and the line drawing of the part without the latent image and the line drawing of the part with the latent image Since the upper boundary line and the boundary line between the image area and the non-image area on the fixed-period discontinuity line of the part where the latent image is not applied and the part where the latent image is applied are not necessarily in the same direction as each other, the latent image Can be prevented from interfering with the outline of the image and the line drawing of the copy protection pattern, which effectively affects the invisibility of the latent image with the naked eye.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. The copy prevention pattern by the line drawing configuration of the present invention is
Originally, as shown in FIG. 3, a line drawing (6) of a portion where a latent image is not applied and a line drawing (7) of a portion where a latent image is applied are used. In order to show the configuration in more detail, a description will be given with reference to FIG. 4 on the assumption that the curved line drawing is a straight line. FIG. 4 is an enlarged view of a boundary portion of each line drawing on the assumption that a line drawing of a portion where a latent image is not applied and a line drawing of a portion where a latent image is applied are linearly continuous. Accordingly, the basic curve (8) and the latent image in FIG. 5 showing the line image configuration of the portion where the latent image is not applied and the portion where the latent image is applied when the copy protection pattern of the present invention is constituted by a curved line image. A straight line (11) tangent to the basic curve (8) at an intersection (10) with the contour (9) of the basic curve (8), and a portion where the basic curve (8) is not subjected to the latent image and a portion where the latent image is applied. A straight line (11) that is in contact with the basic curve (8) at an intersection (10 ′) of the boundary between the image portion and the non-image portion on the fixed-period break line is a basic curve (8) in FIG. ).

First, in FIG. 4, the image width in the direction perpendicular to the basic curve of the image portion of the fixed-period disconnection line at the portion where no latent image is applied is A, and the constant-periodic disconnection line at the portion where no latent image is applied. B is the length of the image portion in the direction of the basic curve, B is the length of the image portion in the direction perpendicular to the basic curve of the image portion of the fixed-period discontinuity line where the latent image is applied, and A is the portion where the latent image is applied. The length b in the basic curve direction of the image portion of the fixed-period discontinuity is denoted by b, and the length in the basic curve direction of the non-image portion of the fixed-periodic discontinuity portion where the latent image is applied is denoted by C. The expansion value (or contraction value) generated around the line portion is defined as χ ′. Here, in the case of printing the copy protection pattern by the line drawing configuration of the present invention, in order to obtain the effect of the present invention as described above, in order to obtain the effect of the present invention, the fixed-period disconnection line of the part where the latent image is not applied and the part where the latent image is applied Since the image area of the periodic break is an important factor, consider the change in the image width in the direction perpendicular to the basic curve and the image length in the basic curve direction in the image area during printing. Is preferred. On the printed matter, the image width in the direction perpendicular to the basic curve of the image portion (12) of the fixed-period discontinuity portion where the latent image is not applied is A + χ '+ χ', and the image portion (12)
Is B + χ ′ + χ ′, and the image width in the direction perpendicular to the basic curve of the image portion (13) of the fixed-period disconnection line at the portion where the latent image is formed is a + χ ′ + χ ′, The length of the image portion (13) in the direction of the basic curve is b + χ '+ χ'. In order to produce the functions and effects of the present invention, when a printed matter having the line drawing configuration of the present invention is copied by a copying machine, the periodic periodic disconnection of a portion where no latent image is formed is reproduced as it is due to the resolution of the copying machine. Since it is necessary that the periodic broken line in the portion where the latent image is applied is not reproduced or the reproduction becomes defective, (B + χ ′ + χ ′)> (b +
χ '+ χ'), and at the same time, the fixed-period discontinuity of the part where the latent image was not applied and the fixed-periodic discontinuity of the part where the latent image was applied seemed to be the same density. The image areas of portions corresponding to the one cycle of the periodic discontinuity line must be equal to each other. That is, in the line drawing configuration exhibiting the effects of the present invention, in the stage of line drawing design, the line width A in the direction perpendicular to the basic curve of the line portion (12) of the fixed-period discontinuity portion where the latent image is not applied is set. The image width a in the direction perpendicular to the basic curve of the image portion (13) of the fixed-period discontinuity line in the portion where the latent image is applied is given by: a = ｛A · B + (A + B) · (χ ′)
+ Χ ') + (χ' + χ ') ・ (χ' + χ ')｝ / (b +
関係 '+ χ')-(χ '+ χ') must be satisfied.

Further, the line drawing construction of the copy prevention pattern of the present invention is based on a line drawing of a portion where a latent image is not formed and a line drawing of a portion where a latent image is formed to form a curved aggregate pattern. Consisting of fixed-period disconnection lines consisting of objects of a predetermined shape with constant image width in the direction perpendicular to the basic curve, arranged at regular intervals in the curve direction, and fixed-period disconnection lines of each part The image area of the part corresponding to the one period of the fixed-period discontinuity of each part, in which the length of one cycle composed of one object part and the non-object part continuous in the basic curve direction is equal to each other Are equal to each other. On the printed matter, assuming that the length in the basic curve direction of the non-image portion of the fixed-period discontinuity line of the portion where the latent image is applied is C, the C shown in FIG. 4 is such that the latent image is not visually recognized by the naked eye, and It may be set in the range of 30 μm to 60 μm which is not resolved by the copying machine.

Further, in the conventionally disclosed printed matter for copy protection, since latent images are formed by the density of screen patterns at halftone dots or lines, etc., the latent image of each image forming the copy protection pattern is hidden. The direction of the boundary line on the object line between the part where the image is not applied and the part where the latent image is applied is regulated in the same direction at the boundary between the part where the latent image is not applied and the part where the latent image is applied. However, interference occurred due to the nature of the image, and the latent image was visually recognized.
As shown in FIG. 5, the line drawing configuration according to the present invention employs a method of increasing the invisibility of a latent image in a copy protection pattern, as shown in FIG. 5, on a line drawing of a portion where a latent image is not applied and a line drawing of a portion where a latent image is applied. The boundary line (15) is a straight line that intersects a straight line (11) tangent to the basic curve (8) at an intersection (10) between the basic curve (8) and the contour line (9) of the latent image,
At the same time, the boundary (1) between the image portion and the non-image portion on the fixed-period disconnection line of the portion where the latent image is not applied and the portion where the latent image is applied, respectively.
4) a straight line (11) tangent to the basic curve (8) at an intersection (10 ') between the basic curve (8) and the boundary line (14) between the image area and the non-image area on the periodic break. May be a straight line that intersects at a substantially right angle. By the way, FIG.
As shown in FIG. 5, when the boundary line (15) and the contour line (9) of the latent image are in the same direction, and the boundary line (14) is in one direction regardless of the basic curve (8), the present invention described above. Even if the line drawing design method is used, the boundary line (1
5) has a regularity in the same direction as the contour line (9) of the latent image and causes interference, and the boundary line (14) is in the same direction as the basic curve (8) depending on the location. Interference occurs due to regularity. On the other hand, in the present invention, as shown in FIG.
At the intersection of the basic curve (8) and the contour line (9) of the latent image, a straight line that intersects the straight line (11) tangent to the basic curve (8) at a right angle can be used. The boundary line (15) between the fixed-period disconnection line of the part and the fixed-periodic disconnection line of the part on which the latent image is applied, and the contour line (9) of the latent image can have no regularity in the same direction. Therefore, when a copy prevention pattern is printed using the line drawing configuration according to the present invention, the image portion (1
2) The image portion (1)
3), between the contour line (9) of the latent image and the boundary line (14) between the image portion and the non-image portion on the fixed-periodic discontinuity line of each of the portion where the latent image is not applied and the portion where the latent image is applied Can be prevented.

An embodiment of the present invention will be described in more detail.
Generally, a colored pattern is a pattern drawn on a mathematical function according to a design. Therefore, as a device for creating the pattern, a device for drawing by a mechanical operation such as a gear and a cam, and a two-dimensional drawing using a computer. Although there is an apparatus for drawing by a function on coordinates, in this embodiment, a commercially available computer
An example using a graphic design device (hereinafter referred to as CGS) will be described.

In the present invention, as described above, when designing a line drawing at the time of plate making in consideration of the expansion value (or shrinkage value) of an image line at the time of printing, the expansion value (or shrinkage value) is determined in advance by a test image. Investigated by line. As a test object, a printed matter (16) as shown in FIG. 7 having the form of a conventional colored pattern having an image width of 134 μm on the original plate for making a plate was prepared. This printed matter (16) uses commercially available coated paper (SK coat) as the paper, and determines the rheological suitability of the ink.
After performing offset printing with a commercially available offset ink (gray) having a viscosity of 99 poise and a tack value of 4.4, which is a general suitability, the printed pattern (17) of the printed matter (16)
As a result of measuring the object width of the object (18), the measured value was 150 μm.
It was found that the expansion value (or shrinkage value) χ ′ generated around the image when printing was 8 μm.

By using the expansion value of 8 μm generated around the image obtained by the test object, the basic curve of the image portion of the fixed-period discontinuity portion where no latent image is formed is formed by the line image configuration of the present invention. A printing plate was prepared for obtaining a colored pattern printed matter FIG. 8 having a printed image line width of 150 μm in a direction perpendicular to the above. First, using a commercially available CGS, a basic curve (8) consisting of a basic spline curve constituting a color pattern as shown in FIG. 9 is set on two-dimensional coordinates, and a latent image pattern (19)
Was arranged on a basic curve (8) consisting of a spline curve. The latent image pattern may be any character or figure as long as the printed matter of the present invention can be clearly identified by visual inspection when copied by a copier by an unskilled person. The boundary between the line image where the latent image is not applied and the line image where the latent image is applied is a partially enlarged view of the basic curve (8) composed of the spline curve and the outline (9) of the latent image pattern in FIG. It is formed at the intersection (10) of the contour line (9) of the latent image pattern and the basic curve (8) in FIG.

First, in the copy-prevention color pattern to be created in the present embodiment, the print image in the direction perpendicular to the basic curve of the image portion of the fixed-period disconnection line in the portion where the latent image is not applied in FIG. Set the line width to 150 μm, and
Was set to 134 μm by subtracting the expansion value 16 μm of the object in the object width direction, which was grasped by the test object described above. Next, in order to define a line drawing design of the portion on which the latent image is applied, that is, to define an image width a in the direction perpendicular to the basic curve of the image portion of the fixed-period discontinuity line of the portion on which the latent image is applied in FIG. The length b in the basic curve direction of the image portion of the fixed-period disconnection line in the portion where the latent image is applied, and the length C in the basic curve direction of the non-image portion of the constant-periodic disconnection line in the portion where the latent image is applied It is necessary to set. First, as for the length b + χ '+ χ' in the basic curve direction of the image portion of the fixed-period disconnection line of the portion where the latent image is provided on the printed matter, the latent image is not visually recognized by the naked eye, and is resolved by the copying machine. Since the output resolution of a general copying machine is assumed to be 400 dpi, one pixel is 64 μm. Therefore, a length of 64 μm or less is suitable as a measure of the length that is difficult to be resolved. Length b + χ '+ χ' is 4
It was set to 0 μm. Therefore, by subtracting the expansion value 16 μm of the image in the direction of the basic curve as grasped by the test image, b
Was set to 24 μm. Next, the length C in the basic curve direction of the non-image portion of the fixed-period discontinuity line of the portion on which the latent image is applied is 30 in a range where the latent image is not visually recognized by the naked eye and is not resolved by the copying machine.
μm to 60 μm are possible, but in this embodiment, 60 μm
And Accordingly, the length W in the direction of the basic curve of one period of the fixed-period discontinuity line between the portion where the latent image is not applied and the portion where the latent image is applied
Was 100 μm of 24 + 16 + 60. Further, when a printed matter having the line drawing configuration of the present invention is copied by a copying machine, the periodic power of the portion where no latent image is formed is reproduced as it is by the resolving power of the copying machine, and the fixed period of the portion where the latent image is formed is reproduced as it is. Since it is necessary that the broken line is not reproduced or the reproduction becomes defective, (B + χ ′ + χ ′)> (b +
χ '+ χ') must be satisfied, and 100> (B
+ Χ '+ χ')> 40 is an essential condition. Therefore, the length B in the basic curve direction of the image portion of the fixed-period discontinuity portion where no latent image is formed in the line image design is set to 64 μm, and B + χ ′
+ Χ 'was set to 64 + 8 + 8 of 80 μm. Therefore, when the image width A in the direction perpendicular to the basic curve of the image portion of the fixed-period discontinuity line where the latent image is not applied is set to 134 μm, when the set b and B are applied to the above calculation formula, a = $ 13
4 × 64 + (134 + 64) × (8 + 8) + (8 + 8)
× (8 + 8)｝ / (24 + 8 + 8) − (8 + 8), and an image width a of 284 μm was obtained in a direction perpendicular to the basic curve of the image portion of the fixed-period discontinuity portion where the latent image was formed.

Further, on the two-dimensional data, as shown in FIG. 11, the image portion (12 ') of the fixed-period discontinuity portion of the portion where no latent image is formed in the line drawing design stage, based on the numerical values obtained by the above formula. The image width A in the direction perpendicular to the basic curve of
34 μm, length B in the basic curve direction of the image area (12 ′)
Is 64 μm, and the image width a in the direction perpendicular to the basic curve of the image portion (13 ′) of the fixed-period discontinuity line where the latent image is applied is 2 μm.
84 μm, length b in the basic curve direction of the image area (13 ′)
A 24 μm, the periodic pattern discontinuity of the portion where the latent image is not applied and the periodic curve discontinuity of the portion where the latent image is applied and the length W in the basic curve direction of one cycle are 100 μm. Using a laser plotter, obtain a film master for plate making,
A printing plate was prepared using a commercially available positive type PS plate. Next, using the obtained printing plate, on a commercially available coated paper (SK coat),
A commercially available offset ink (gray) with a rheological suitability of 99 poise and a tack value of 4.4. The adjustment of the printing equipment is the same as general lithographic offset printing. Offset printing is performed without special adjustment. 8 were obtained.

When the printed matter shown in FIG. 8 is visually observed, the observer may notice that the line drawing of the portion where the latent image is applied and the line drawing of the portion where the latent image is not applied are fixed-period discontinuous lines having different shapes from each other. Regardless, by recognizing the image as a single continuous image in the direction of the basic curve, it is possible to make it impossible for the naked eye to identify the latent image at all. Therefore,
The observer cannot visually recognize the existence of the portion (20) provided with the latent image at all unless the user attempts to magnify the printed line drawing, and at first glance, the printed matter (21) having the colored pattern (21) provided with the latent image 22) looks the same printed matter as the printed matter (16) having the conventional colored pattern (17) of FIG.

FIG. 12 shows a copy (23) obtained by copying a printed matter having a color pattern of the present invention shown in FIG. 9 by a color copying machine (Canon Color Laser Copier 470). The part (25) provided with the latent image in FIG. 12 opposite to the part (20) provided with the latent image shown in FIG. Since only) is a recognizable line drawing, it was in the state of a visible image (25), and it was obvious at a glance that it was a duplicate using a copying machine. This makes it possible to determine the authenticity.

[0022]

According to the present invention, as described above, the latent image cannot be recognized at all by the naked eye, and when the image is copied by a copying machine, the portion on which the latent image is formed cannot be reproduced, and the latent image is visualized. Therefore, forgery and alteration by the copying machine can be prevented. In the color pattern of the present invention, since the latent image cannot be easily identified with the naked eye even in single-color printing, there is no need to dare overprint the camouflage pattern, and the color pattern can be used as a single-color tint pattern. it can. As a result, the present invention is a technology for preventing counterfeiting and falsification of securities such as banknotes, stock certificates, bonds, etc., and various certificates and important documents, which must be prevented from falsification and falsification by a copying machine. It is valid.

[Brief description of the drawings]

FIG. 1 is a pattern of a conventional copy prevention printed matter and a partially enlarged view of the pattern.

FIG. 2 shows a pattern of a copy of a conventional copy protection print and a partially enlarged view of the pattern.

FIG. 3 is a partially enlarged view of the copy preventing pattern of the present invention and the pattern.

FIG. 4 is an enlarged view of a boundary between a line drawing of a portion where a latent image is not applied and a line drawing of a portion where a latent image is applied;

FIG. 5 is a diagram showing a line drawing configuration of a portion where a latent image is not applied and a portion where a latent image is applied;

FIG. 6 shows that the boundary between the line image of the portion where the latent image is not applied and the line image of the portion where the latent image is applied is in the same direction as the outline of the latent image. Diagram showing the case where the boundary between the image area and the non-image area on each periodic break is set to one direction regardless of the basic curve

FIG. 7 is a conventional printed matter having a color pattern and an enlarged view of the pattern.

FIG. 8 is an enlarged view of a printed matter having a color pattern of the present invention and the pattern.

FIG. 9 is a diagram in which a basic curve and a latent image pattern constituting a color pattern are set.

FIG. 10 is a partially enlarged view of a basic curve and a latent image pattern constituting a color pattern;

FIG. 11 is a diagram illustrating a line drawing on two-dimensional data of a color pattern according to the present invention;

FIG. 12 is a copy of a printed matter provided with a colored pattern of the present invention and a partially enlarged view of the copied pattern.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Conventional printed matter for copy prevention 2 Pattern of the whole printed surface 3 Screen pattern of dense composition not reproduced on printed matter 3 'Screen pattern of dense composition not reproduced on copied matter 4 Screen pattern of coarse composition reproduced on printed matter 4 '' Coarse-structured screen pattern reproduced on the copy 5 Interference with the boundary line of the latent image 6 Line drawing of the part without the latent image 7 Line drawing of the part with the latent image 8 Basic curve 9 Outline of the latent image 10 Intersection point between basic curve and contour line of latent image 10 'Intersection point between basic line and boundary line between image area and non-image area on fixed-period line 11 Straight line tangent to basic curve 12 Area where no latent image is applied Image part of fixed-period disconnection line 12 'Image part of fixed-periodic discontinuity part where no latent image is applied 13 Image part of fixed-periodic disconnection part where latent image is applied 13' Image part of periodic breaks 14 Apply latent image The boundary between the image portion and the non-image portion on the fixed-period discontinuity line of the non-image portion and the latent image portion 15 The boundary line between the line image of the portion where the latent image is not applied and the line image of the portion where the latent image is applied 16 Printed matter with conventional colored pattern 17 Conventional colored pattern 18 Conventional colored pattern object 19 Latent image pattern 20 Latent image applied part 20 'Latent image applied part 21 Latent image applied Colored pattern 21 'Line drawing of a part without a latent image 22 Printed matter having a colored pattern with a latent image 23 Duplicate 24 Colored pattern of a duplicate 24' Line drawing of a colored pattern of a duplicate 25 Visualized A latent The image width in the direction perpendicular to the basic curve of the image portion of the fixed-period discontinuity line where no image is applied B The length of the image portion of the constant-periodic disconnection line where no latent image is applied in the basic curve direction C The length of the non-image area of the fixed-period discontinuity line in the part where the latent image was applied in the direction of the basic curve a. The width of the image in the direction perpendicular to the basic curve of the image portion of the fixed-period disconnection line of the part b The length of the image portion of the fixed-periodic disconnection line where the latent image is applied in the direction of the basic curve W The latent image is applied The length of one cycle of the periodic cutoff line in the part where there is no part and the periodic cutoff line of the part where the latent image was applied in the direction of the basic curve χ 'The expansion value (or contraction value) generated around the image

Claims (12)

(57) [Claims] 1. A line drawing of a portion where a latent image is not formed and a line drawing of a portion where a latent image is formed forming a curved aggregate pattern are arranged at regular intervals in the direction of a basic curve for each portion. One object that is composed of fixed-period discontinuities consisting of objects of a predetermined shape with a constant object width in the direction perpendicular to the basic curve, and is continuous in the direction of the basic curve of the constant-period discontinuity of each part Wherein the lengths of one cycle comprising a portion and a non-image portion are equal to each other, and the image areas of portions corresponding to the one cycle of the fixed-period discontinuity of each portion are equal to each other. How to create a pattern. 2. A line drawing of a portion where a latent image is not formed and a line drawing of a portion where a latent image is formed forming a curved aggregate pattern are arranged at regular intervals in a basic curve direction for each portion. One object that is composed of fixed-period discontinuities consisting of objects of a predetermined shape with a constant object width in the direction perpendicular to the basic curve, and is continuous in the direction of the basic curve of the constant-period discontinuity of each part Wherein the lengths of one cycle comprising a portion and a non-image portion are equal to each other, and the image areas of portions corresponding to the one cycle of the fixed-period discontinuity of each portion are equal to each other. Printed matter with a pattern. 3. A boundary line on a line drawing between a line drawing of a portion where a latent image is not applied and a line drawing of a portion where a latent image is applied is defined by a line tangent to the basic curve at an intersection of the basic curve and the outline of the latent image. , And a straight line that intersects at a substantially right angle.In addition, the boundary line between the image area and the non-image area on the fixed-period break line of the part where the latent image is not applied and the part where the latent image is applied is the basic curve and the fixed period. 2. The anti-copying pattern according to claim 1, wherein the straight line intersects a straight line at a right angle to a straight line tangent to the basic curve at an intersection of an image portion on the discontinuity and the boundary line of the non-image portion. How to make. 4. A boundary line between a line drawing of a portion where a latent image is not applied and a line drawing of a portion where a latent image is applied is different from a straight line tangent to the basic curve at the intersection of the basic curve and the outline of the latent image. , And a straight line that intersects at a substantially right angle.In addition, the boundary line between the image area and the non-image area on the fixed-period break line of the part where the latent image is not applied and the part where the latent image is applied is the basic curve and the fixed period. 3. The copy protection pattern according to claim 2, wherein the straight line intersects a straight line at a right angle to a straight line that is tangent to the basic curve at an intersection of an image portion on the broken line and the boundary line of the non-image portion. Printed matter. 5. The method according to claim 1, wherein the curvilinear aggregate pattern is a tint block or a color pattern. 6. The printed matter having a copy protection pattern according to claim 2, wherein the curved aggregate pattern is a tint block or a color pattern. 7. The method according to claim 3, wherein the curvilinear aggregate pattern is a tint block or a color pattern. 8. The printed matter having a copy protection pattern according to claim 4, wherein the curved aggregate pattern is a tint block or a color pattern. 9. The method according to claim 1, wherein the curved aggregate pattern is a relief pattern. 10. The printed matter having a copy protection pattern according to claim 2, wherein the curved aggregate pattern is a relief pattern. 11. The method according to claim 3, wherein the curved aggregate pattern is a relief pattern. 12. The printed matter having a copy protection pattern according to claim 4, wherein the curved aggregate pattern is a relief pattern.