JPH09136479A - Method for preparing copy-preventive pattern and printed matter thereof - Google Patents

Abstract

(57) Abstract: The present invention relates to a printed matter in which a set of curved lines is provided with a latent image that cannot be generally recognized by the naked eye, and a method for producing the printed matter. The printed matter of the present invention is intended to provide a forgery and alteration prevention effect of securities such as banknotes, stock certificates and bonds, various certificates and important documents by a copying machine. According to the present invention, in a set pattern of curved lines, a part without a latent image is represented by a single line, a part with a latent image is represented by two or more lines, and a part with a latent image is represented by two or more lines. The part which is not latent image is branched so that the total line width of all the image lines of is equal to the line width of the image line of one line without latent image And the boundary line on the image line of the latent image is a straight line that intersects at a right angle with the straight line that touches at the intersection of the basic curve forming the pattern and the contour line of the latent image. In an image line that is a set of two or more lines of a part, at the portion where the image lines of each set intersect, the image line of either one of the image lines of each set is Deleted within the range between the strokes of one set of strokes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a latent image, which is usually invisible to the naked eye, to a collection pattern of curved lines, and in a printed matter requiring forgery and alteration prevention, the latent image is not reproduced when copied by a copying machine. The present invention relates to a method for producing a developed copy protection pattern 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 are a tint block pattern, a color pattern, and a relief pattern, which are widely used in the design of printed matters such as securities. The latter representative example is a latent image intaglio, and colors are normally reproduced by a copying machine. There are functional inks and copy protection lines that are not protected. 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.

Countermeasures against forgery and alteration using the above-mentioned geometric pattern include a tint block, a color pattern, and a relief pattern.
Basically, a pattern is composed of a set of curved strokes having a constant stroke 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, etc., and at the same time, they have been used for a long time as patterns of printed matter with monetary value such as banknotes, stocks, bonds, etc. However, in general, it is an important pattern as a design that impresses with luxury. Therefore, banknotes,
In printed matters such as securities such as stock certificates and bonds, various certificates and important documents, a tint block, a color pattern, a relief pattern and the like are indispensable in terms of design. However, there is a drawback in that the advent of photoengraving apparatuses or copiers with advanced functions has not provided sufficient counterfeiting and alteration prevention effects recently.

[0004] Further, when some means and action are applied to the above-mentioned printed matter, as a typical technique of a method of displaying a latent image which could not be visually recognized, a copy protection image is generally called. There are a series of techniques. That is, the latent image applied to the printed matter appears by copying with a copying machine. In such a printed matter suitable for preventing forgery by a copying machine, for example, 85 lines 3 are printed on the surface of the base paper.
A latent image on which characters composed of fine constituent elements, which are 0% halftone dots, is displayed is printed using silver ink, and then, in a blank portion other than this latent image, a coarser or denser area (for example, 150 lines 30).
%) Printed with a halftone dot and a printed pattern such as a tint pattern or a tint pattern on the upper surface of the latent image, which is suitable for preventing forgery by copying (JP-A-57-20395). In addition, a latent image is printed on the surface of the paper with halftone dots, a background with the same density as the latent image is printed simultaneously with a line, and a decorative pattern on the upper surface of the latent image including the background is of a light color that is not reproduced by copying. By overprinting with transparent ink, the surface of the printed matter is finished in a good appearance, and when copied, the pattern disappears, the background is reproduced and the latent image is not reproduced, and the density difference between the background and the latent image becomes obvious. A printed material suitable for copy prevention, which can be seen at a glance as a copied material (Japanese Patent Laid-Open No. 60-79991).
Gazette), which further comprises a latent image consisting of 150 lines and 10% halftone dots, and 50 to 60 lines 1 on the white ground around the latent image.
Using a latent image plate with a background consisting of about 0% lines
A dark color is printed on the surface of the paper, and an overprint plate with a wavy pattern consisting of parallel lines that forms a moire pattern when it interferes with the background lines is used. Overprinting creates a moire pattern on the surface of the printed matter that is dazzling to the naked eye, making it difficult to identify the presence of a latent image.When applied to a copier, the latent image and waveform pattern are not reproduced, but only the background is reproduced. As a result, the latent image is recognized as distinguished from the background, and a latent image cam-image method for preventing copy in printed matter (Japanese Patent Laid-Open No. 60-8738).
No. 0) and the like are disclosed.

In each of the printed materials according to the above publications, a latent image is formed by the density of image lines (hereinafter, referred to as a screen pattern) in which dots and lines such as lines are continuously arranged at a constant cycle. The pattern (2) on the entire printed surface as shown in the printed matter (1) is a screen pattern having a uniform density. When the printed matter (1) provided with the latent image is copied by a copying machine, the dense screen pattern (3) which is not reproduced and the coarse screen pattern (4) which is reproduced are the copied matter of FIG. As shown in the pattern (2 ') of 1'), the latent image portion of the screen pattern (3 ') of the dense structure which is not reproduced is displayed in contrast to the screen pattern (4') of the coarse structure which is reproduced due to the density difference. Although it is made clear so that it is a copy, it is a screen pattern with uniform density over the entire printing surface. Therefore, there is a drawback that the existence of the latent image can be identified by the sense of distinction due to the difference in the screen shape and the interference portion (5) with the boundary line of the latent image caused by the screen pattern. As a method for solving the above-mentioned drawbacks, all of the above-mentioned publications and the like provide different patterns, light-colored transparent ink, and light-color overprinting in order to camouflage the latent image, but the method is difficult to identify the latent image. However, it has the drawback of increasing the number of steps and not being economical.

Further, the inventors of the present invention simultaneously print, with one color, a latent image having a pattern of halftone dots or lines on the surface of the paper and a background having a pattern having a different density from the latent image around the latent image. In the printed matter, the latent image pattern provided with the latent image is not discernible by the naked eye, and as a printed matter suitable for copy prevention (JP-A-4-170569), another pattern for camouflaging the latent image or A method of camouflaging with a light-colored transparent ink, and without performing light-color overprinting, with a white circular pattern or a concentric pattern with an increased dot percentage of the partial screen pattern with respect to the entire screen pattern. I have already applied,
As described above, in each of the above-mentioned conventional techniques, the latent image is easily visible because the latent image is formed by the screen pattern.
In the case of a single-color printed matter, the information such as characters to be overwritten separately on the printed matter must play the role of camouflage, so it can only be used for the tint block pattern that forms the background of documents, etc. It is impossible to make the line pattern itself into a freely designed pattern such as a sill pattern, or to make an artistic printed material with a decorative effect. Furthermore, since all of the above-mentioned conventional methods must be screen patterns consisting of dots and lines such as lines and the like, and the density of lines and lines, a tint block, a stipple pattern, such as banknotes, stock certificates, bonds, etc. It has a drawback that it is not suitable for use in existing products such as securities.

[0007]

Therefore, the applicant of the present application is
In order to solve the above-mentioned drawbacks, as a method of increasing the non-visibility of a latent image in a copy protection pattern, a portion without a latent image is represented by one line, and a portion with a latent image is represented by two or more lines. The image line of two or more lines in the portion on which the latent image is applied has a total image line width of the image lines of two or more lines equal to the image line width of the image line of one line on which the latent image is not applied, and The boundary line between the non-latent image part and the non-latent image part is the intersection of the basic curve and the latent image contour line that form the copy protection pattern. Proposes a method for producing a copy-preventing pattern having a drawing structure that intersects at a right angle with a straight line in contact with a basic curve and a printed matter thereof (Japanese Patent Application No. 6-206140). According to this method of creating a copy-preventive pattern, the boundary line between the image line of the portion not subjected to the latent image and the image line of the portion subjected to the latent image and the contour line of the latent image do not have regularity in the same direction. Therefore, interference can be prevented, and it is not necessary to camouflage the latent image, and it can be used for existing products.
The present invention is a further improvement of the above-mentioned method of creating a copy protection pattern, and can be applied to securities such as banknotes, stock certificates, bonds, etc., including various certificates and important documents requiring copy protection. By providing a latent image that is not normally visible to the naked eye on a set pattern of curved lines, overprinting for cam framing is not required, and a method of creating a copy prevention pattern having a forgery / alteration prevention effect by a copying machine and its It provides printed matter.

[0008]

[Means for Solving the Problems] The means for solving the above problem is that, in the above-mentioned image line construction, a collective pattern of curved image lines includes one line for a portion without a latent image and two or more lines for a portion with a latent image. An image with two or more lines in the latent image is represented by a line, and the total line width of the lines with two or more lines is the image of one line of the line without the latent image. It is characterized by branching from a single line that is equal to the width and has no latent image. Furthermore, the boundary line on the image line between the part without the latent image and the part with the latent image is a straight line tangent to the basic curve at the intersection of the basic curve and the contour line of the latent image, which constitutes the collective pattern of the curved lines. ,
It is characterized by being a straight line that intersects at a substantially right angle. Furthermore, in an image line that is a set of two or more lines of the latent imaged part, one of the image lines of each set is a part where the image lines of each set intersect. It is characterized in that the image lines of the group of No. 2 are deleted within the range between the image lines of the other set of image lines to prevent the density increase of the image lines occurring at the intersecting portions.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION A printed matter suitable for preventing forgery by a conventional copying machine is provided with a latent image due to the density of screen patterns such as halftone dots or lines, so that the entire printed surface becomes a screen pattern having a uniform density. On the other hand, the streak structure of the present invention is a curved streak forming a collective pattern, a part without a latent image is represented by one line, and a part with a latent image is represented by two or more lines. The image line of two or more lines in the portion on which the latent image is applied has a total image line width of the image lines of two or more lines equal to the image line width of the image line of one line on which the latent image is not applied, and The copy-preventing pattern is constituted by an image line which is branched from the single-line image line on which the latent image is not applied. Therefore, when the printed matter on which the copy-preventing pattern of the present invention is printed with a change in printing, that is, an expansion value is taken into consideration, is observed as a whole, the observer observes that the latent image portion has two or more lines. Despite this, it is possible to make the latent image indistinguishable by the naked eye by extending the portion without the latent image, that is, by recognizing it as if it were a single-line drawing line. ing. Therefore, when a printed matter having the image line structure of the present invention is copied by a copying machine, a single line image line of a portion without a latent image is reproduced due to the resolution of the copying machine, and a double line of a portion with a latent image is reproduced. The above-described image lines are not reproduced, or due to poor reproduction, a density difference occurs between a portion with a latent image and a portion without a latent image, and a latent image is developed.

Further, the boundary portion on the image line between the portion on which the latent image is not formed and the portion on which the latent image is formed, that is, the boundary line on the image line is at the intersection of the basic curve forming the copy protection pattern and the outline of the latent image. By forming a straight line that intersects with a straight line that is in contact with the basic curve at a substantially right angle, the intersections have different angles according to the curve shape of the basic curve. Therefore, the boundary line on the image line between the non-latent imaged portion and the latent imaged portion is constantly changed by the curved shape of the copy protection pattern regardless of the latent image contour line, and the latent imageless portion and the latent image are not changed. Since the boundary lines of the shaded portions are not in the same direction, it is possible to prevent the contour line of the latent image and the image line of the copy protection pattern from interfering with each other, which effectively acts on the non-visibility of the latent image by the naked eye.

Further, in the image lines which are a set of two or more lines of the latent imaged part, in the part where the image lines of each set intersect, the image lines of each set are By deleting the image lines of either one of the groups within the range between the image lines of the image lines of the other set, when the copy protection pattern of the present invention is viewed as a whole, the latent image in the pattern is eliminated. In the part where two or more lines of the imaged part intersect with each other, even if it seems that there is a part intersecting the curved line, the part where the latent image is actually applied In (1), since either one of the drawing lines is deleted inside the drawing lines, there is no intersection (overlap) between the drawing lines. Therefore, it is possible to prevent the density of the image lines from increasing at the intersection of the image lines. As a result, when a printed matter having the image streak structure of the present invention is copied by a copying machine, the image of a single line without a latent image is reproduced due to the resolving power of the copying machine. Image lines larger than the main line are not reproduced, or due to poor reproduction, not only a density difference occurs between the latent image area and the non-latent image area, but also between the image areas of the latent image area. For the intersecting (overlapping) portion, one of the image lines is deleted inside the image line, so that the portion corresponding to the apparent intersection of the portions is not reproduced in the same manner without increasing the density. Alternatively, due to poor reproduction, the latent image is more clearly developed and becomes a visible image without hindering the development of the latent image.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The drawing line construction of the copy protection pattern of the present invention will be described with reference to the drawings. The copy protection pattern according to the streak structure of the present invention is
Originally, as shown in FIG. 3, it is composed of the curved line of the image line (6) of the part without the latent image and the image line (7) of the part with the latent image. In order to make the line configuration more detailed, description will be given with reference to FIG. 4 assuming that the curved line is a direct line. Fig. 4 shows the drawing lines of the part without the latent image.
It is the figure which expanded the boundary part on each drawing line, assuming that the drawing line of the part which gave the latent image intersects with a straight line. Therefore, when the copy protection pattern of the present invention is composed of curved lines, the basic curve forming the basic pattern forming the pattern in FIG. 5 showing the line drawing structure of the part without the latent image and the part with the latent image. At the intersection (10) of (8) and the contour line (9) of the latent image, the straight line (11) tangent to the basic curve (8) is the same as the basic curve (8) in FIG.

First, in FIG. 4, the sum of the image widths of the image lines (13) of two or more lines in the portion where the latent image is formed is the image line of the image line (12) of one line where the latent image is not formed. In order to make the width equal to the width, at the stage of drawing line design, the drawing line width of the part where the latent image is not applied is A, and the drawing line width of two or more lines of the part where the latent image is applied is one line drawing width each. a, where n (two in FIG. 4) is the number of branches of the image lines in the latent imaged area, a = A / n. However, in the case of printing a copy protection pattern according to the image line construction of the present invention, the effect of the present invention is exerted as described above because the image lines used in the non-latent image portion and the latent image portion are obtained. Since it depends on the width, it is preferable to consider a change in the line width during printing. That is, in the case of designing an image line in which the influence on the image line width at the time of printing is taken into consideration, the expansion value (or contraction value) generated on one side of the image line at the time of printing as shown in FIG. When this is done, the image width of the image line (12) in the portion where the latent image is not applied on the printed matter is A +
χ '+ χ', and the image width of each image line (13) of the latent imaged portion on the printed matter is a + χ '+ χ'
In the image line configuration that achieves the effect of the present invention, the image line width A of a single line without a latent image and the image line width a of each of two or more lines with a latent image are , A = {A-
It suffices to satisfy the relationship of (χ '+ χ') (n-1)} / n.

Next, in the streak structure of the copy protection pattern of the present invention, two or more streak lines of the latent image-bearing portion are branched from one line of the non-latent image-bearing portion. The spacing between the image lines of each image line (13) of the latent imaged portion on the printed matter (ie,
When S is the inner edge), S shown in FIG. 4 may be set to 30 μm to 60 μm in a range in which the latent image is not visually recognized by the naked eye and is not resolved by the copying machine.

Next, when the copy-preventing pattern of the present invention is used as a printed matter, when two or more lines of the latent image-bearing part are visually observed, they are continuous with one line of the non-latent image-bearing part. It looks like a single line. In order to design the image line (7) of the latent image-applied portion that branches from the image line (6) of the non-latent image shown in FIG. 3, the image line is drawn from the basic curve (8) shown in FIG. At the stage of designing, the distance to the latent image curve (14) that forms the center of the drawing width a of the outermost latent image portion and the two adjacent latent image curves (14) It is necessary to obtain the distance between the latent image curves (14), and the distance from the basic curve (8) to the outermost latent image curve (14) is W ', and each adjacent latent image curve (14) When the distance between the two is W, the visible image of the above-mentioned copy-preventing pattern printed product of the present invention can be seen as a continuous single line. The positional relationship of the image lines (12) in the part where the latent image is not applied is W ′ =
{(N-1) (S + χ '+ χ' + a)} / 2 and W = 2
By obtaining W '/ (n-1), a copy-preventing pattern and a printed matter having a high copy-preventing effect can be obtained.

Further, as a method for enhancing the non-visibility of the latent image in the copy-preventing pattern of the present invention, in the copy-preventing printed matter disclosed hitherto, the dots and lines of halftone dots or lines are hidden by the density of the screen pattern. Since the image is applied, the direction of the boundary line on the image line between the non-latent image part and the latent image part of each image line forming the copy protection pattern is the same as the non-latent image part. At the boundary of the portion where the latent image is applied, interference occurs due to the regularity in the same direction, and the latent image is visually recognized, which is one factor that forces the use of the camouflage pattern. However,
As shown in FIG. 5, the streak structure of the present invention is such that the boundary line (15) on the streak line between the non-latent imaged portion and the latent imaged portion is
At the intersection (10) of the basic curve (8) constituting the copy protection pattern and the contour line (9) of the latent image, it intersects with the straight line (11) in contact with the basic curve (8) at a right angle.
That is, as shown in FIG. 6, even when the above-described image line designing method of the present invention is used, the image line (12) of the part where the latent image is not applied and the image line () of the part where the latent image is applied ( Since the boundary line (15) of 13) has regularity in the same direction as the contour line (9) of the latent image, as shown in FIG. 7, it is an image area of a portion where the latent image is not originally applied. (B) and (C), which is the image area of the portion on which the latent image is originally applied, should be the same as the image area of the portion on which the latent image is applied, and (C) area By designing the drawing lines so as to be the same as the drawing lines of the portion where the latent image is not applied, as shown in FIG.
5) is a straight line that intersects the straight line (11) in contact with the basic curve (8) at a substantially right angle at the intersection of the basic curve (8) and the contour line (9) of the latent image. The boundary line (15) between the image line (12) and the image line (13) of the latent image portion and the latent image contour line (9) have no regularity in the same direction. Therefore, when a copy protection pattern is printed using the image line construction according to the present invention, the image line of the portion where the latent image is formed (13) and the image line of the portion where the latent image is not formed (1
The interference between 2) and the contour line (9) of the latent image can be prevented.

Next, as a method of more clearly visualizing the manifestation of the latent image at the time of copying the copy protection pattern of the present invention, as shown in FIG.
3), that is, in a set of two or more lines, one set is formed at an intersection (10 ') at a portion where the latent image curves (14) of the set (13) intersect each other. For each of the lines (13) of one of the lines (13), the image line (13) of the other set is the line (1) of one set.
3) When located within the range between the image lines, the inside of the space between the image lines of the other set of image lines (13) is deleted only at that portion, so that the copy protection pattern of the present invention is entirely removed. When it is seen, even if it seems that there is a part where two or more lines in the pattern where the latent image is applied intersects with each other, it is actually applied with the latent image. In the part, there is no intersection (overlap) between the drawing lines. Therefore, it is possible to prevent an increase in the density of the image line generated at the intersecting portion. That is, normally, when the pattern is created, as shown in FIG. 6, the image lines (13) of the portion on which the latent image is applied are completely crossed, but as shown in FIG. Line (1
3) At the intersection (10 ') where the parts are about to intersect,
The drawing area (13) of either one of the above-mentioned drawing lines (13) for each set is positioned within the range between the drawing lines of the drawing line (13) of the other set ( D) is deleted. In the description of the present embodiment, the upper image line is deleted at the intersection of the image lines of each set of the latent image-provided portion, but the present invention is not limited to the above-described embodiment, and Since only one of the lines may be deleted, the lower line may be deleted. As a result, when a printed matter having the image streak structure of the present invention is copied by a copying machine, the image of a single line without a latent image is reproduced due to the resolving power of the copying machine. Image lines larger than the main line are not reproduced, or due to poor reproduction, not only a density difference occurs between the latent image area and the non-latent image area, but also the intersection of the image areas of the latent image area ( (Overlap) deletes one of the strokes inside the strokes, so the portion corresponding to the apparent intersection is not reproduced in the same way without increasing the density, or due to reproduction failure. Further, it is possible to more clearly express the latent image without inhibiting the development of the latent image.

The embodiment of the present invention will be described in more detail.
Generally, a color pattern is a pattern drawn on a mathematical function according to a design, and therefore, as a device for creating the pattern, a device for drawing by a mechanical operation of a gear, a cam or the like, and a two-dimensional computer There is a device for drawing by a function on coordinates, but in the present embodiment, a commercially available computer graphic design device (hereinafter referred to as CGS).
An example using will be described.

In the present invention, as described above, the expansion value (or contraction value) of the image line at the time of printing is taken into consideration, and the expansion value (or contraction value) is tested in advance when designing the image line at the time of plate making. It was investigated with a streak. As a test image, a printed matter (16) as shown in FIG. 8 having a conventional color pattern pattern having an image width on the plate making film original plate of 100 μm was prepared. In this printed matter (16), commercially available coated paper (SK coat) is used as the paper, and the rheological suitability of the ink is
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, a color pattern (17) of the printed matter (16)
As a result of measuring the line width of the image line (18) of 116 μm, the expansion value of the entire image line is 16 μm, and the expansion value (or the contraction value) generated on one side of the image line when printing is performed.
It was found that χ'is 8 μm.

By using the value of the expansion value of 8 μm generated on one side of the image line obtained by the test image line, by the image line construction of the present invention, a print pattern width of 116 μm in the print line width of the portion where the latent image is not applied A printing plate was prepared for obtaining the printed matter FIG. First, a commercially available CGS is used to set a basic curve (8), which is a basic spline curve constituting a color pattern pattern drawing line as shown in FIG. 10, on a two-dimensional coordinate, and a latent image pattern (19) is set.
Were arranged on a basic curve (8) consisting of a spline curve. The latent image pattern may be in the form of characters or figures as long as it can be clearly identified by visual inspection when the printed matter of the present invention is reproduced by an inexperienced person by a copying machine. The drawing of the image line of the part where the latent image is not applied and the image line of the part where the latent image is applied are created by partially enlarging the basic curve (8) consisting of the spline curve in FIG. 10 and the boundary part (9) of the latent image pattern. The latent image pattern (1
This is done at the intersection (10) between the area 9) and the basic curve.

First, since the print line width of the copy-preventing color pattern to be created in this embodiment is 116 μm,
Assuming that the print line width opposite to the basic curve (8) is 116 μm, the line width in the image line design is 100 obtained by subtracting the expansion value 16 μm of the entire print image line grasped by the test line described above.
It was set to μm. Next, the drawing line design of the part with the latent image,
That is, the image width a of the latent image-applied portion in FIG. 4 and the positional relationship between the image line 12 of the non-latent image portion and the image line 13 of the latent image portion are defined. It is necessary to set the distance W'from the basic curve (8) to the latent image curve (14), and as described above, they are a = {A-
(Χ '+ χ') (n-1)} / n and W '= {(n-
1) (S + χ '+ χ' + a)} / n.

However, the number of lines n in the portion where the latent image is formed is n
And the space S between the latent image and the latent image is
It is necessary to set in advance. First, in setting the number n of lines of the latent image, it is necessary that the latent image is not visible to the naked eye and is not resolved by the copying machine. Since the width of one line is 64 μm per pixel when the output resolution of a general copying machine is 400 dpi, 64 μm or less is suitable as a guideline for the line width that is difficult to be resolved. Since the printed line width of the printed matter is set to 116 μm as described above, the number n of image lines in the latent image formed portion is set to n = 2 from the relation of 116 μm / 64 μm. Next, the interval S between the image line of the latent image-formed portion and the image line of the latent image-formed portion is 30 μm in a range in which the latent image is not visually recognized by the naked eye and is not resolved by a copying machine.
Although it can be up to 60 μm, it is set to 50 μm in this embodiment. Applying the set n and S to the above formula, a
= {100− (8 + 8) (2-1)} / 2, and the image width of one of the latent imaged portions is 42 μm, and the distance W from the basic curve (8) to the latent image curve (14) is W. 'Is W' =
With {(2-1) (50 + 8 + 8 + 42)} / 2, 54 μ
Since m is obtained, the latent image curve (14) of the region (19) of the portion to be subjected to the latent image of FIG. 12 in CGS is the basic curve (8) which is a spline curve on the boundary line (9) of the latent image. Based on the intersection point (10) of (4), it was set at a position widened to both sides by 54 μm as indicated by W ′ with respect to the basic curve (8).

Next, in the latent image curve (14) shown in FIG. 12, that is, in the image line which is a set of two lines, the intersection (10) of the portions where the latent image curves (14) of each set intersect each other. ')
Then, for each set of latent image curves (14), the latent image curve (14) of the other set is applied to the latent image curve (1) of the other set.
To delete 4) within the range between the lines of the latent image curve (14) of one set, cut the line of the other set on the intersection (10 ') and Delete the latent image curve (14). As a result, it is possible to create a state in which there is no intersection (overlap) between the image lines in the latent imaged portion.

Further, according to the numerical values of the drawing width obtained by the above formula and the drawing width of the portion where the latent image is applied, the latent value opposite to the basic curve (8) is set on the two-dimensional data as shown in FIG. The image width A of the image line (12 ') in the non-image area is 100μ
m, the latent image curve (1
4) A striated pattern in which the image width (a) of the image line (13 ′) of the portion opposite to 4) is 42 μm is used to obtain a film master plate for plate making using a commercially available laser plotter, and a commercially available positive type A printing plate was prepared with a PS plate. Next, using the obtained printing plate, a commercially available offset ink (gray) having a viscosity of 99 poise and a tack value of 4.4 on a commercially available coated paper (SK coat) was used as a printing device. The adjustment was the same as that of general lithographic offset printing, and offset printing was performed without special adjustment to obtain the printed matter of FIG.

When the printed matter shown in FIG. 9 is visually observed, the image line of the portion where the latent image is not formed is double although the image line (20 ') of the portion where the latent image is formed is two lines to the observer. (2
1 ') is extended, that is, it is recognized as if it is a single line. Therefore, the observer cannot see the existence of the latent imaged portion (20) at all unless he / she attempts to magnify the printed image line, and at first glance, the latent imaged iris pattern (21) is seen. The printed matter (22) possessed looks the same as the printed matter (16) having the conventional color pattern (17) of FIG. 8.

FIG. 14 shows a duplicate (23) obtained by duplicating FIG. 9 of the printed matter having the color pattern of the present invention by a color copying machine (Canon Color Laser Copier 470). A latent image portion (2) shown in FIG. 14 opposite to the latent image portion (20) shown in FIG.
5) becomes unreproducible by the copying machine, and a grayscale difference is generated from the image of the single line of the portion (21 ') not subjected to the latent image in the partially enlarged view of FIG. 9, and the latent image becomes a duplicate (FIG. 14). Since only the image line (24 ') of the portion where the latent image is not applied is recognizable from the striated pattern (24), the image is in the state of the visible image (25), which means that it is a duplicate using a copying machine. It was obvious. This makes it possible to discriminate between true and false.

[0027]

As described above, according to the present invention, the latent image cannot be discerned by the naked eye, and when the image is copied by a copying machine, the latent image portion cannot be reproduced and the latent image is visualized. Furthermore, in the curved image lines of the portion where the latent image is applied, at the portion where the image lines of each set intersect (overlap), the image line of either one of the image lines of each set is Since it is deleted inside the line between the lines of the set of lines, there is no intersection (overlap) between the lines in the part where the latent image is applied, so the density is not high, Similarly, the portion corresponding to the intersection also becomes unreproducible, and the latent image can be expressed more clearly without hindering the development of the latent image, which is effective for the forgery and alteration prevention effect by the copying machine. is there. In addition, since the latent image of the chromatic pattern of the present invention cannot be easily identified with the naked eye even in monochromatic printing, it is not necessary to overprint the camouflage pattern, and the chromatic pattern can be used as a monochrome tint pattern. In addition, it is possible to use printed materials that use other types of forgery prevention measures such as moire patterns in the background pattern and color patterns on the same drawing line. Banknotes, stock certificates, bonds, etc. that must prevent forgery and alteration by a copying machine are also possible. It is effective as a technology for preventing forgery and alteration of securities, various certificates and important documents by copying machines.

[Brief description of the drawings]

FIG. 1 shows a pattern of a conventional copy-preventing printed matter and a partially enlarged view of the pattern.

FIG. 2 shows a pattern of a conventional copy-preventing printed matter and a partially enlarged view of the pattern.

FIG. 3 shows a copy protection pattern of the present invention and a partially enlarged view of the pattern.

FIG. 4 is an enlarged view of a boundary portion between a portion without a latent image and a portion with a latent image.

FIG. 5 is a diagram showing an image line configuration of a portion on which a latent image is not applied and a portion on which a latent image is applied.

FIG. 6 is an explanatory diagram of a boundary portion between a portion without a latent image and a portion with a latent image.

FIG. 7 is an explanatory diagram of a boundary portion between a portion without a latent image and a portion with a latent image.

FIG. 8 shows a printed matter having a conventional color pattern and an enlarged view of the pattern.

FIG. 9 shows an enlarged view of a printed matter having a color pattern of the present invention and the pattern.

FIG. 10 shows a diagram in which a basic curve and a latent image pattern that form the basis of a striated pattern drawing line are set.

FIG. 11 is an enlarged view in which a basic curve and a latent image pattern that form the basis of a striated pattern drawing line are set.

FIG. 12 shows a diagram in which a latent image curve is set in the color pattern of the present invention.

FIG. 13 is a drawing line configuration diagram on the two-dimensional data of the color pattern of the present invention.

FIG. 14 is a partially enlarged view of a duplicate of a printed matter on which the colored pattern of the present invention is applied and the pattern.

[Explanation of symbols]

1 Conventional Copy Protection Printed Material 2 Pattern on Entire Printed Surface 3 Non-Reproduced Dense Structured Screen Pattern on Printed Material 3 ′ Non-Regenerated Densely Configured Screen Pattern 4 Regenerated Coarsely Configured Screen Pattern on Printed Material 4 'Coarsely constructed screen pattern reproduced on copy 5 Interference with boundary line of latent image 6 Image line of non-latent image part 7 Image line of latent image part 8 Basic curve 9 Latent image Contour line 10 Intersection of basic curve and latent image contour line 10 'Intersection point of one latent image curve and other latent image curve 11 Straight line in contact with basic curve 12 Image line of non-latent image 12' Latent image Image line of non-applied area 13 Image line of latent image area 13 'Image line of latent image area 14 Latent image curve forming the center of each image line width of latent image area 15 Latent image Apply the streak and latent image of the part that is not Boundary line of partial image lines 16 Printed matter having a conventional color pattern 17 Conventional color pattern 18 Line of color pattern of a conventional print 19 Latent image pattern 20 Latent image portion 20 ' Streaked part 21 Streaked pattern with latent image 21 'Streaked part without latent image 22 Printed product with latent image applied stylus 23 Duplicate 24 Duplicate crest pattern 25 Visible image A The image width of the part where the latent image is not applied B The image area of the part where the latent image is applied C The image area of the part where the latent image is not applied D The image area where the part where the latent image is applied is deleted a The latent image Each drawing width of two or more drawing lines of the applied part n The number of branched lines of the drawing of the latent image χ'Expansion value (or contraction value) generated on one side of the drawing S Latent image The distance between the inner edges of the lines of the marked part W The distance between the adjacent latent image curves W'Basic Distance from curve to latent image curve

Claims (12)

[Claims] 1. A set pattern of curved lines is represented by a single line for a portion without a latent image and two or more lines for a portion with a latent image, and two or more lines for a portion with a latent image. The line width of the line is equal to the line width of the line of the single line where the latent image is not applied, and the line width of the line of two or more lines is equal to the line width of the line where the latent image is not applied. In an image line that is branched and further has a set of two or more lines of the latent image-applied portion, at a portion where the image lines of each set intersect with each other, A method for creating a copy protection pattern, characterized in that the image lines of either one of the groups are deleted within the range between the image lines of the image lines of the other group. 2. A set pattern of curved lines is represented by a single line for a portion without a latent image and two or more lines for a portion with a latent image, and two or more lines for a portion with a latent image. The line width of the line is equal to the line width of the line of the single line where the latent image is not applied, and the line width of the line of two or more lines is equal to the line width of the line where the latent image is not applied. In the image line that is branched as an image line that takes into account changes during printing, and is a set of two or more lines of the portion on which the latent image is applied, at the portion where the image lines of each set intersect with each other. , A copy protection pattern characterized in that either one of the groups of the above-mentioned image lines is deleted and printed within a range inside the image lines of the other set of image lines. Printed matter having. 3. A boundary line on the image line between the non-latent imaged portion and the latent imaged portion is in contact with the basic curve at the intersection of the basic curve forming the aggregate pattern of the curved image lines and the latent image contour line. The method for producing a copy protection pattern according to claim 1, wherein the straight line intersects the straight line at a substantially right angle. 4. A boundary line on an image line between a portion without a latent image and a portion with a latent image is in contact with the basic curve at an intersection of a basic curve forming a collective pattern of curved lines and a contour line of the latent image. A printed matter having a copy-preventing pattern according to claim 2, wherein the printed line is a straight line that intersects the straight line at a substantially right angle, and is further printed with consideration given to changes during printing. 5. The method for producing a copy protection pattern according to claim 1, wherein the set pattern of the music lines is a tint block pattern or a color pattern pattern. 6. The printed matter having a copy protection pattern according to claim 2, wherein the collective pattern of the curved lines is a tint block pattern or a color pattern pattern. 7. The method of creating a copy protection pattern according to claim 3, wherein the collective pattern of the curved lines is a tint block pattern or a color pattern pattern. 8. The printed matter having a copy protection pattern according to claim 4, wherein the collective pattern of the curved lines is a tint block pattern or a color pattern pattern. 9. The method for producing a copy protection pattern according to claim 1, wherein the set pattern of the curved lines is a relief pattern. 10. The printed matter having a copy protection pattern according to claim 2, wherein the collective pattern of the curved lines is a relief pattern. 11. The method for producing a copy protection pattern according to claim 3, wherein the set pattern of the curved lines is a relief pattern. 12. The printed matter having a copy protection pattern according to claim 4, wherein the set pattern of the curved lines is a relief pattern.