Printed matter and authenticity determination method

Abstract

To provide a printed matter capable of being produced at a low cost by using only a general printing process not limited to a hue change which a material has.SOLUTION: A printed matter obtained by printing a plurality of image lines on a printing substrate is such that: each of the plurality of image lines has a height from the printing substrate, which is maximum in a central part in the line width orthogonal to the orientation direction, and minimum in both ends in the line width; each of the plurality of image lines has a cross-sectional shape swelling from both ends to the central part in the line width direction; the plurality of image lines belong to any group in a plurality of image line groups comprising image lines in which a gap between the adjacent image lines in the line width direction, and their line widths and orientation directions are the same; and one or more image line groups having an orientation direction different from that of the other image line group exist in the plurality of image line groups.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to printed matter that requires anti-counterfeiting effect and is applicable to, for example, banknotes, passports, securities, identification cards, cards, travel tickets, etc., and to a method for determining the authenticity of such printed matter. [Background technology]

[0002] With the recent development of digital devices such as scanners, printers, and color copiers, it has become possible to easily create elaborate copies of printed materials. In order to prevent such copying and counterfeiting, counterfeit prevention technology is needed. Among the above-mentioned counterfeit prevention technologies, there is a particular need for counterfeit prevention technology such as watermarks and holograms that does not require tools and can be used by anyone who holds a printed material to determine its authenticity.

[0003] One type of anti-counterfeiting technology that does not require such tools and can be used by anyone to distinguish authenticity is the use of optically variable inks that contain functional pigments that change color when light is reflected. Images printed using these inks change color when light is reflected, so discriminators can determine the authenticity of printed materials by checking the color change. Representative examples of optically variable inks include pearl ink and OVI (Optical variable Ink), which are used on banknotes. The former changes the image from clear to pink at a specific reflection angle, and the latter changes from blue-green to purple, etc.

[0004] As an advanced technology for the color change of these optically changing inks, for example, Patent Documents 1 and 2 disclose inks that contain optical interference pigments and have a color shift effect or light / dark flip-flop properties or color flip-flop properties, which are arranged in a kamaboko or embossed pattern and the viewing angle and embossing gradient angle are changed, so that at a certain reflection angle, the color of a certain area in a printed image gradually changes from one color to a different color, and the color change in this area can also be controlled by changing the reflection angle, causing it to appear to move. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4967569 [Patent Document 2] Patent No. 5967651 Summary of the Invention [Problem to be solved by the invention]

[0006] However, although the techniques described in Patent Documents 1 and 2 can provide color-changing printed matter, they utilize the effect caused by the optical properties of a specific functional pigment contained in the ink, and in order to bring out that effect, it is necessary to have a three-dimensional structure such as a kamaboko-shaped raised shape or embossed processing on the base. This requires a dedicated manufacturing device to obtain the three-dimensional shape, and the manufacturing process is complicated and expensive.

[0007] The present invention has been made in consideration of these circumstances, and its first object is to provide a printed matter that can be produced at low cost using only general printing processes that are not limited by the color changes inherent to the material.

[0008] A second object of the present invention is to provide an authenticity determining method that can easily determine the authenticity of such printed matter. [Means for solving the problem]

[0009] In order to achieve the above object, the present invention takes the following measures.

[0010] That is, a first aspect of the present invention is a printed matter having a plurality of image lines printed on a printing substrate, wherein the height of each of the plurality of image lines from the printing substrate is greatest at the center of the line width perpendicular to the orientation direction and is smallest at both ends of the line width, each of the plurality of image lines has a cross-sectional shape that rises from both ends toward the center in the line width direction, each of the plurality of image lines belongs to one of a plurality of image line groups consisting of image lines having the same gap with adjacent image lines in the line width direction, line width, and orientation direction, and the plurality of image line groups includes at least one image line group having an orientation direction different from the other image line groups.

[0011] A second aspect of the present invention is a printed matter according to the first aspect, in which the line width is greater than 0.0 mm and less than 0.5 mm, the height from the printing substrate at the center is greater than 0.0 mm and less than 0.01 mm, and the cross-sectional shape is an arc that is highest at the center and lowest at both ends.

[0012] A third aspect of the present invention is the printed matter according to the first aspect, wherein in each group of images, the gap is 0.0 mm or more and 0.5 mm or less.

[0013] A fourth aspect of the present invention is a printed matter according to the first aspect, in which the plurality of image groups includes at least one image group that has the same line width and gap as any one of the plurality of image groups but has a different orientation direction.

[0014] A fifth aspect of the present invention is a printed matter according to the first aspect, in which the plurality of image groups includes at least one image group that has the same orientation direction as any one of the plurality of image groups but differs in at least one of the line width and the gap.

[0015] A sixth aspect of the present invention is a printed matter according to the first aspect, wherein the plurality of image groups includes at least one image group in which the image lines are arranged in a line pattern, a curved pattern, a concentric circle pattern, or a pattern formed by a combination of any of these patterns.

[0016] A seventh aspect of the present invention is a printed matter according to the first aspect, in which a latent image is embedded that is determined based on the number of multiple image groups, the placement position and area of ​​each image group on the printing substrate, the line width, gaps, and orientation direction of the images in each image group.

[0017] An eighth aspect of the present invention is the printed matter according to the seventh aspect, in which the image is formed with a transparent or opaque ink.

[0018] A ninth aspect of the present invention is a printed matter according to the eighth aspect, wherein the plurality of image groups includes at least one image group in which all of the image lines are formed with ink of the same color.

[0019] A tenth aspect of the present invention is a printed matter according to the eighth aspect, wherein the plurality of image groups includes at least one image group including image lines formed with inks of different colors.

[0020] An eleventh aspect of the present invention is a printed matter according to the tenth aspect, in which gloss and hue are imparted to the latent image by a combination of different colors in a group of images including images formed with inks of different colors.

[0021] A twelfth aspect of the present invention is a method for determining the authenticity of a printed matter described in the first aspect, which determines the authenticity of a printed matter based on an image that appears on the printed surface while the printed matter is rotated while the printed surface on which the image lines are printed is kept facing the illumination light from a fixed light source.

[0022] A thirteenth aspect of the present invention is the method for determining authenticity according to the twelfth aspect, wherein the image changes in response to the print being rotated.

[0023] A fourteenth aspect of the present invention is a method for determining authenticity according to the thirteenth aspect, in which a printed matter is determined to be authentic if the image changes in a predetermined manner in response to the printing matter being rotated. Effect of the Invention

[0024] According to the present invention, it is possible to provide a printed matter that can be produced at low cost using only a general printing process, without being limited by the color change inherent to the material.

[0025] It is also possible to provide a method for easily determining the authenticity of such a printed matter. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 is a schematic plan view showing an example of a printed matter according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic cross-sectional view illustrating a part of the image line in FIG. [Diagram 3] FIG. 3 is a perspective view illustrating reflected light appearing on the surface of a printed matter according to the prior art. [Figure 4] FIG. 4 is a perspective view illustrating reflected light appearing on the surface of a printed matter according to an embodiment of the present invention. [Diagram 5] FIG. 5 is a diagram for explaining a mechanism for generating reflected light that appears on the surface of a printed matter according to an embodiment of the present invention. [Figure 6] FIG. 6 is a plan view showing an example of how a latent image embedded in a printed matter according to an embodiment of the present invention appears. [Figure 7] FIG. 7 is a plan view showing an example of how a latent image embedded in a printed matter according to an embodiment of the present invention appears. [Figure 8] FIG. 8 is a plan view showing an example of how a latent image embedded in a printed matter according to an embodiment of the present invention appears. [Figure 9] FIG. 9 is a conceptual diagram showing the principle of a printing device applied to printing of a printed matter according to an embodiment of the present invention. [Figure 10] FIG. 10 is a diagram showing each process up to when a printed matter is printed by the printing device shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] An embodiment of the printed matter according to the present invention will be described with reference to the drawings. The drawings are schematic, and the relationship between planar dimensions and the thickness ratio of each layer are different from the actual ones. The embodiments shown below are examples of configurations for embodying the technical idea of ​​the present invention, and the technical idea of ​​the present invention is not limited to the materials, shapes, structures, etc. of the components described below.

[0028] (Printed material) A printed matter according to an embodiment of the present invention will be described.

[0029] FIG. 1 is a schematic plan view showing an example of a printed matter according to an embodiment of the present invention.

[0030] FIG. 2 is a schematic cross-sectional view illustrating a part of the image line in FIG.

[0031] That is, the printed matter 1 according to this embodiment is formed by printing a large number of objects a, shown by solid lines in Fig. 1, on the surface of a printing substrate 2. The objects a are formed with transparent or opaque ink.

[0032] Each of the objects a belongs to one of a plurality of object groups a0 to a6, each of which has the same line width w, the same gap s between adjacent objects a in the line width direction, and the same orientation direction perpendicular to the line width direction. Note that the object groups a0 to a6 are merely examples, and it should be understood that the printed matter 1 of the present invention may include more or less object groups.

[0033] Among the multiple image groups a0 to a6, there is at least one image group in which all the images a are formed with the same color ink, and there may also be at least one image group including images a formed with inks of different colors.

[0034] As shown in Fig. 2, the height h of each object a from the printing substrate 2 is maximum (h2) at the center of line width w and minimum (h1, h3) at both ends of line width w, and each object a has a cross-sectional shape that rises in the line width direction (left-right direction in Fig. 2) from both ends having minimum heights h1, h3 toward the center having maximum height h2. In other words, the object a has an arc-shaped cross-sectional shape (kettle-boiled fish shape) in which the center is highest and both ends are lowest in the line width direction.

[0035] The line width w is greater than 0.0 mm and equal to or less than 0.5 mm, the maximum height h2 is greater than 0.0 mm and equal to or less than 0.01 mm, and the gap s is equal to or greater than 0.0 mm and equal to or less than 0.5 mm.

[0036] In the first image group a0, an image a is printed with a line width w, a gap s between adjacent images, and an orientation direction that are specific and constant for the image group a0. In the example shown in FIG. 1, the image a in the image group a0 is a straight line with an orientation direction of 135°. The orientation direction can be any direction within the range of 0° to 360° shown in FIG. 1. The first image group a0 also includes an area other than the second image groups a1 to a4, the third image group a5, and the fourth image group a6 described below.

[0037] In the second image groups a1 to a4, an image a is printed with a line width w, a gap s, and an orientation direction that are specific and constant for each image group a1 to a4. In the example shown in Fig. 1, the image a in image group a1 is a straight line oriented at 90°, the image a in image group a2 is a straight line oriented at 0°, the image a in image group a3 is a straight line oriented at 45°, and the image a in image group a4 is a straight line oriented at 135°. The orientation direction can be any direction within the range of 0° to 360° shown in Fig. 1, as in the case of the first image group a0.

[0038] The third image group a5 is printed with a number of images a oriented in a concentric circle. Within the image group a5, the line width w of the images a is specific and constant for the image group a5, and the gap s between adjacent images a in the radial direction of the circle is also specific and constant for the image group a5.

[0039] The fourth object group a6 is printed with a large number of curved objects a. Within the object group a6, the line width w of each object a is specific and constant for the object group a6, and the gap s between adjacent objects a is also specific and constant for the object group a6.

[0040] The image groups in the printed matter 1 include at least one image group in which the image lines a are arranged in a line pattern, a curved pattern, a concentric circle pattern, a wavy line pattern (not shown in Fig. 1), or a pattern formed by a combination of any of these patterns. In the printed matter 1 shown in Fig. 1, the image groups a0 to a4 are formed of the image lines a arranged in a line pattern, the image group a5 is formed of the image lines a arranged in a concentric circle pattern, and the image group a6 is formed of the image lines a arranged in a curved pattern.

[0041] Furthermore, in the printed matter 1, among the multiple image groups such as image groups a0 to a6, there is at least one image group that has an orientation direction different from the other image groups. In the printed matter 1 illustrated in Fig. 1, image group a0 and image group a4 have the same orientation direction, but the orientation directions of the other image groups a1 to a3 and a5 to a6 are all unique and different from the orientation directions of the other image groups.

[0042] Furthermore, in the printed matter 1, among the multiple image groups such as image groups a0 to a6, there is at least one image group that has the same orientation direction as one of the image groups but differs in at least one of the line width w and the gap s. In the printed matter 1 illustrated in Fig. 1, image group a0 and image group a4 have the same orientation direction and the line width w of image a is also the same, but the gap s of image a is different, with image group a4 being narrower.

[0043] A printed matter 1 configured in this manner can have embedded therein a latent image that is determined based on the length, width, number, and placement position on the printing substrate 2 of image groups such as image groups a0 to a6, as well as the line width w, gap s, and orientation direction of the image lines a in each of image groups a0 to a6.

[0044] In other words, the length, width, number, placement position on the printing substrate 2, line width w, gap s, and orientation direction of the image a in each of the image groups a0 to a6 can be determined according to the design of the latent image to be embedded.

[0045] Furthermore, by combining different colors in the image group including the image a formed with inks of different colors, it is possible to impart gloss and hue to the latent image.

[0046] As explained with reference to FIG. 2, the image line a has a kamaboko-shaped cross section, the line width w is greater than 0.0 mm and not greater than 0.5 mm, the maximum height h2 is greater than 0.0 mm and not greater than 0.01 mm, and the gap s is greater than 0.0 mm and not greater than 0.5 mm, which is also advantageous in imparting a glossy appearance and hue to the latent image.

[0047] FIG. 3 is a perspective view illustrating reflected light appearing on the surface of a printed matter according to the prior art.

[0048] 3(a) and 3(b) show printed matter 50 of a general planar structure according to the prior art, both of which are printed solidly, for example in black, using general halftone dots or the like, on a substrate 2. Fig. 3(a) shows, in a simplified manner, the reflected light seen in response to incident light from a light source 60 parallel to the Y direction on the printed matter 50, and Fig. 3(b) shows, in a simplified manner, the reflected light seen in response to incident light from a light source 60 parallel to the X direction on the printed matter 50.

[0049] As illustrated in FIG. 3(a), when light I is incident from a light source 60 parallel to the Y direction, reflected light R having a shape matching the shape of the light source 60 is recognized at a certain position.

[0050] Next, while keeping the position of the light source 60 fixed, the print object 50 is rotated 90° on the XY plane from the state shown in FIG. 3(a) to the state shown in FIG. 3(b).

[0051] Similarly, as illustrated in FIG. 3(b), when light I is incident from the light source 60 parallel to the X direction, reflected light R having a shape that matches the shape of the light source 60 is recognized at the same position on the printed matter 50.

[0052] In the printed matter 50 having a planar structure formed by halftone dots in this way, even if the orientation or position of the printing base material 2 is changed, only the same reflected light R is recognized, and the light and dark state does not change.

[0053] FIG. 4 is a perspective view illustrating reflected light appearing on the surface of a printed matter according to an embodiment of the present invention.

[0054] As described above, in the printed matter 1 according to the embodiment of the present invention, the object a having a kamaboko-shaped cross section is printed on the printing substrate 2, but for ease of explanation, the object a is shown as a black cylindrical shape in Fig. 4. Also, in the printed matter 1 according to the embodiment of the present invention, the object a oriented in different orientation directions is printed on the printing substrate 2, but for ease of explanation, the object a is oriented only in the X direction in the figure in Fig. 4.

[0055] FIG. 5 is a diagram for explaining a mechanism for generating reflected light that appears on the surface of a printed matter according to an embodiment of the present invention.

[0056] As shown in Fig. 4(a), when light I is incident on printed matter 1 from light source 60 in a direction parallel to the Y direction, reflected light R-1, R-2, ...Rn is generated near surface b-1 of object a-1, near surface b-2 of object a-2, ...near surface bn of object an (n is an arbitrary integer equal to or greater than 3), as shown in Fig. 5(a), and reflected light R is recognized from all objects. As a result, a viewer 70 sees linear reflected light R extending in a band in the orientation direction of object a (Y direction in the figure), as shown in Fig. 4(a).

[0057] Next, while keeping the position of the light source 60 fixed, the printed matter 1 is rotated 90° on the XY plane from the state shown in FIG. 4(a) to the state shown in FIG. 4(b), in the same manner as in FIG.

[0058] In this state, the direction of the incident light I from the light source 60 coincides with the orientation direction of the object a. In this case, as shown in FIG. 5(b), the incident light I from the light source 60 is reflected by the surface of the object a-1 and diffuses in the peripheral direction of the object a-1, and almost no reflected light R-1 reaches the observer 70. Similarly, for the objects a-2,...an, the incident light I-2,...In from the light source 60 is reflected by the surface of the objects a-2,...an and diffuses in the peripheral direction of the objects a-2,...an, and almost no reflected light R-2,...Rn reaches the observer 70. Therefore, the observer 70 visually recognizes a state in which there is no reflected light R, as shown in FIG. 4(b).

[0059] Thus, when the direction of the incident light I is 0°, the reflected light R at the object a is weakest when the orientation direction of the object a is 0°. The reflected light R is strongest when the direction of the incident light I and the orientation direction of the object a are perpendicular to each other at 90°. In other words, the reflected light R gradually becomes stronger as the orientation direction of the object a changes from 0° to 90° with respect to the direction of the incident light I, and conversely becomes weaker when the orientation direction exceeds 90°, being weakest at 180°. The change in the intensity of the reflected light R when the orientation direction of the object a changes from 180° to 270° with respect to the direction of the incident light I and the change in the intensity of the reflected light R when the orientation direction of the object a changes from 270° to 360° are similar to the change in the intensity of the reflected light when the orientation direction of the object a changes from 0° to 90° with respect to the direction of the incident light I and the change in the intensity of the reflected light when the orientation direction of the object a changes from 90° to 180°.

[0060] However, if the line width w of the image line a is greater than 0.5 mm, even if the image line is printed as a group of images, each image line a is visible separately, and is not recognized as a solid print state. The reflected light R is also recognized as a line, and therefore it is not possible to achieve the glossiness that would be obtained by uniform reflection from a solid surface.

[0061] Moreover, since it is recognized as the image a, the latent image is already recognized regardless of the presence or absence of the reflected light R.

[0062] Similarly, if the distance s between the image lines a is greater than 0.5 mm, each image line a will be visible regardless of its line width w, and it will not be possible to achieve the glossiness that would be obtained from a solid surface that reflects light evenly.

[0063] In this case as well, since it is recognized as the image a, the latent image is already recognized regardless of the presence or absence of the reflected light R.

[0064] Furthermore, if the maximum height h2 of the object a is greater than 0.01 mm, the object a and the unevenness of the base surface of the printing base material 2 will be recognized. In other words, since each object a will be visually recognized, a solid printing state will not be achieved, and it will be impossible to achieve the glossiness that would be achieved by a solid surface that reflects evenly.

[0065] In this case as well, since it is recognized as the image a, the latent image is already recognized regardless of the presence or absence of the reflected light R.

[0066] 6, 7, and 8 are plan views showing examples of how a latent image embedded in a printed matter according to an embodiment of the present invention appears.

[0067] In particular, Figure 6 shows a printed matter 1a including a second image group a1-a4 in which the image lines a are arranged in a line pattern, Figure 7 shows a printed matter 1b including a third image group a5 in which the image lines a are arranged in a concentric circle pattern, and Figure 8 shows a printed matter 1c including a fourth image group a6 in which the image lines a are arranged in a curved line pattern.

[0068] First, with reference to FIG. 6, a description will be given of how a latent image appears on a printed matter 1a including a second group of objects a1 to a4 in which the objects a are arranged in a parallel line pattern.

[0069] The printed matter 1a shown in Figure 6(a) corresponds to the upper half of the printed matter 1 shown in Figure 1, so duplicate explanation will be avoided, but the second image groups a1 to a4 are arranged in order from the left side of the figure on the printing substrate 2, and the first image group a0 is arranged around them, with the orientation direction of the first image group a0 being the 135° direction, and the orientation directions of the second image groups a1, a2, a3, and a4 being the 90° direction, 0° direction, 45° direction, and 135° direction, respectively.

[0070] The height direction angles of the light source 60 and the viewer 70 can be set to any positions where they do not overlap, and the light source 60 is fixed so as to illuminate the printed matter 1a from a direction of 270°. Meanwhile, the viewer 70 can view the printed matter 1a from any angle between 0° and 180° as shown in FIG. 6(a).

[0071] Figure 6(b) shows the state in which an observer 70 observes printed matter 1a from a viewing direction of 135°, Figure 6(c) from a viewing direction of 90°, Figure 6(d) from a viewing direction of 45°, and Figure 6(e) from a viewing direction of 0°.

[0072] In addition, in Figures 6(b) to (e), for the sake of convenience, the areas with the strongest reflected light are shown in white, areas with intermediate intensity in gray, and areas with the weakest reflected light in black.

[0073] In FIG. 6(b), the viewing direction of observer 70 is 135°, which is the same as the orientation direction of the first group of images a0, and the reflected light from image a is the weakest, so the first group of images a0 is represented in black.

[0074] On the other hand, the orientation direction of the image a in the second image groups a1 and a2 each has an absolute angle of 45° with respect to the viewing direction, and the reflected light from the image a is of medium intensity, so the second image groups a1 and a2 are represented in gray.

[0075] The orientation direction of the image a in the second image group a3 is at an angle of 90° to the viewing direction (i.e., perpendicular), and the reflected light from image a is strongest, so the second image group a3 is represented in white.

[0076] The orientation direction of the object a in the second object group a4 is the same as the viewing direction, and the reflected light from the object a is the weakest, so the second object group a4 is displayed in black.

[0077] In Fig. 6(c), the viewing direction of the observer 70 is 90°. Therefore, the orientation direction of the object a in the first object set a0 has an angle of 45° with respect to the viewing direction, and the reflected light from the object a has an intermediate intensity, so that the first object set a0 is represented in gray.

[0078] The orientation direction of the object a in the second object group a1 is the same as the viewing direction, and the reflected light from the object a is the weakest, so the second object group a1 is displayed in black.

[0079] The orientation direction of the object a in the second object group a2 is perpendicular to the viewing direction, and the reflected light from the object a is strongest, so the second object group a2 is displayed in white.

[0080] The orientation direction of the object a in the second object group a3, a4 has an angle of 45° with respect to the viewing direction, and the reflected light from the object a is of medium intensity, so the second object group a3, a4 are represented in gray.

[0081] In Fig. 6(d), the viewing direction of the observer 70 is 45°. Therefore, the orientation direction of the object a in the first object group a0 is perpendicular to the viewing direction, and the reflected light from the object a is strongest, so the first object group a0 is represented in white.

[0082] The orientation direction of the image a in the second image group a1, a2 is at an angle of 45° to the viewing direction, and the reflected light from the image a is of medium intensity, so the second image group a1, a2 are represented in gray.

[0083] The orientation direction of the object a in the second object group a3 is the same as the viewing direction, and the reflected light from the object a is the weakest, so the second object group a3 is displayed in black.

[0084] The orientation direction of the object a in the second object group a4 is perpendicular to the viewing direction, and the reflected light from the object a is strongest, so the second object group a4 is displayed in white.

[0085] In Fig. 6(e), the viewing direction of the observer 70 is 0°. Therefore, the orientation direction of the object a in the first object group a0 has an angle of 45° with respect to the viewing direction, and the reflected light from the object a has an intermediate intensity, so that the second object groups a1 and a2 are represented in gray.

[0086] The orientation direction of the object a in the second object group a1 is perpendicular to the viewing direction, and the reflected light from the object a is strongest, so the second object group a1 is displayed in white.

[0087] The orientation direction of the object a in the second object group a2 is the same as the viewing direction, and the reflected light from the object a is the weakest, so the second object group a2 is represented in black.

[0088] The orientation direction of the object a in the second object group a3, a4 has an angle of 45° with respect to the viewing direction, and the reflected light from the object a is of medium intensity, so the second object group a3, a4 are represented in gray.

[0089] Next, with reference to FIG. 7, the appearance of a latent image in a printed matter 1b including a third object group a5 in which the objects a are arranged in a concentric circle pattern will be described.

[0090] Printed matter 1b shown in Figure 7(a) corresponds to the lower left portion of printed matter 1 shown in Figure 1, so a duplicated explanation will be avoided, but in third object group a5, a large number of objects a are arranged concentrically in a clockwise orientation direction from 0° to 360°. Note that the line width w, gap s, and height h of the objects a are the same regardless of whether they are in first object group a0 or third object group a5.

[0091] Figure 7(b) shows the state in which an observer 70 views printed matter 1b from a viewing direction of 135°, Figure 7(c) from a viewing direction of 90°, Figure 7(d) from a viewing direction of 45°, and Figure 7(e) from a viewing direction of 0°.

[0092] In Figures 7(b) to (e), as in Figures 6(b) to (e), for convenience, the areas with the strongest reflected light are represented in white, areas of intermediate strength in grey, and areas with the weakest reflected light in black. However, in a configuration in which the objects a are arranged in concentric circles, such as the third object group a5, the light and dark areas appear in a gradational manner, rather than a clear change between light and dark as in the second object group a1 to a4 shown in Figures 6(b) to (e).

[0093] In Fig. 7(b), the viewing direction of the observer 70 is 135°, which coincides with the orientation direction of the first image group a0. Therefore, the reflected light from the image a of the first image group a0 is the weakest, and the first image group a0 is represented in black.

[0094] On the other hand, in the third object group a5, the reflected light from object a is weakest in the sector region centered at 45° and 225° in the figure, where the tangent direction of the arc of object a coincides with the viewing direction. In Fig. 7(b), this sector region is shown in black.

[0095] Conversely, the reflected light from object a is strongest in the sector centered at 135° and 315° in the figure, where the tangent direction of the arc of object a is perpendicular to the viewing direction. In Figure 7(b), this sector is shown in white.

[0096] In addition, in sectors centered at 0°, 90°, 180°, and 270° in the figure, where the tangent direction of the arc of object a intersects with the viewing direction at an absolute angle of 45°, the reflected light from object a has an intermediate intensity. In Fig. 7(b), these sectors are shown in gray.

[0097] In Fig. 7(c), the viewing direction of the observer 70 is 90° and the orientation direction of the first image group a0 intersects with the viewing direction at an absolute angle of 45°. Therefore, the reflected light from the image a of the first image group a0 is of intermediate intensity, and the first image group a0 is represented in gray.

[0098] On the other hand, in the third object group a5, the reflected light from object a is weakest in the sector region centered at 0° and 180° in the figure, where the tangent direction of the arc of object a coincides with the viewing direction. In Fig. 7(c), this sector region is shown in black.

[0099] Conversely, the reflected light from object a is strongest in the sectors centered at 90° and 270° in the figure, where the tangent direction of the arc of object a is perpendicular to the viewing direction. In Figure 7(c), these sectors are shown in white.

[0100] In addition, in the sector-shaped regions whose centers are 45°, 135°, 225°, and 315° in the figure, the reflected light from object a has an intermediate intensity. In Fig. 7(c), this sector-shaped region is shown in gray.

[0101] In Fig. 7(d), the viewing direction of the observer 70 is at 45°, which is perpendicular to the orientation direction of the first object group a0. Therefore, the reflected light from the object a of the first object group a0 is strongest, and the first object group a0 is represented in white.

[0102] On the other hand, in the third object group a5, the reflected light from object a is weakest in a sector region centered at 135° and 315° in the figure, where the tangent direction of the arc of object a coincides with the viewing direction. In Fig. 7(d), this sector region is shown in black.

[0103] Conversely, the reflected light from object a is strongest in the sector centered at 45° and 225° in the figure, where the tangent direction of the arc of object a is perpendicular to the viewing direction. In Figure 7(d), this sector is shown in white.

[0104] In addition, in the sector-shaped regions in which the tangent direction of the arc of object a is centered at 0°, 90°, 180°, and 270° in the figure, the reflected light from object a has an intermediate intensity. In Fig. 7(d), this sector-shaped region is shown in gray.

[0105] In Fig. 7(e), the viewing direction of the observer 70 is 0° and intersects with the orientation direction of the first image group a0 at an absolute angle of 45°. Therefore, the reflected light from the image a of the first image group a0 is of intermediate intensity, and the first image group a0 is represented in gray.

[0106] On the other hand, in the third object group a5, the reflected light from object a is weakest in the sector region centered at 90° and 270° in the figure, where the tangent direction of the arc of object a coincides with the viewing direction. In Fig. 7(e), this sector region is shown in black.

[0107] Conversely, the reflected light from object a is strongest in the sector centered at 0° and 180° in the figure, where the tangent direction of the arc of object a is perpendicular to the viewing direction. In Figure 7(e), this sector is shown in white.

[0108] In the sector-shaped regions whose centers are 45°, 135°, 225°, and 315° in the figure, the reflected light from the object a has an intermediate intensity. In Fig. 7(e), this sector-shaped region is shown in gray.

[0109] Next, with reference to FIG. 8, the appearance of a latent image in a printed matter 1c including a fourth object group a6 in which the objects a are arranged in a curved pattern will be described.

[0110] The printed matter 1c shown in Figure 8(a) corresponds to the lower right portion of the printed matter 1 shown in Figure 1, so we will avoid repeating the explanation, but the fourth image group a6 has a large number of images a formed with the same curve printed therein, and the image a has the same line width w, gap s, and height h regardless of whether it is in the first image group a0 or the fourth image group a6.

[0111] Figure 8(b) shows the state in which an observer 70 observes printed matter 1c from a viewing direction of 135°, Figure 8(c) from a viewing direction of 90°, Figure 8(d) from a viewing direction of 45°, and Figure 8(e) from a viewing direction of 0°.

[0112] In Figures 8(b) to (e), as in Figures 6(b) to (e), for convenience, the areas with the strongest reflected light are represented in white, areas of intermediate strength in grey, and areas with the weakest reflected light in black. However, in a configuration in which curved strokes a are arranged as in the fourth stroke group a6, there is no clear change between light and dark as in the second stroke group a1 to a4 shown in Figures 6(b) to (e), but rather light and dark appear in a gradational manner, as in Figures 7(b) to (e).

[0113] In Fig. 8(b), the viewing direction of the observer 70 is 135°, and the orientation direction of the first image group a0 coincides with the viewing direction of the observer 70. Therefore, the reflected light from the image of the first image group a0 is the weakest, and the first image group a0 is represented in black.

[0114] On the other hand, in the fourth object group a6, the reflected light from the object a is weakest in an area a6-1 around 135° where the tangent direction of the curved object a coincides with the viewing direction. This area a6-1 is shown in black in Figure 8(b).

[0115] In the fourth object group a6, the reflected light from the object a is strongest in a region a6-2 where the tangent direction of the curved object a is approximately 90° perpendicular to the viewing direction. This region a6-2 is shown in white in Figure 8(b).

[0116] In the fourth object group a6, the reflected light from the object a has a medium intensity in an area a6-3 other than the areas a6-1 and a6-2. In FIG. 8B, this area a6-3 is shown in gray.

[0117] Due to this mechanism, in the fourth group of images a6, when the observer's field of view direction is 90°, the locations of area a6-1 where the reflected light from image a is the weakest, area a6-2 where the reflected light is the strongest, and area a6-3 where the reflected light is of intermediate strength change, as shown in Figure 8(c), when the observer's field of view direction is 45°, and when the observer's field of view direction is 0°, as shown in Figure 8(d), and when the observer's field of view direction is 0°, as shown in Figure 8(e).

[0118] As explained above using Figures 6, 7, and 8, in the printed matter 1 of this embodiment, the printed line group is recognized as a solid print, and therefore a change in the intensity of reflected light is recognized as occurring on a surface, thereby giving the emerged latent image a metallic glossy appearance.

[0119] Furthermore, since the entire printed matter 1 is formed of the same image line a, when observed without reflected light it appears as a uniform solid print all over; however, when observed in a state where reflected light can be recognized, a latent image is revealed by light and dark as shown in Figure 6.

[0120] Furthermore, in the concentric image group a5 as shown in Figure 7(a), a fan-shaped reflected shape appears as shown in Figures 7(b) to (e), and when the direction of view is continuously shifted, a dynamic visual appearance can be obtained in which the fan-shaped shape also rotates around the center point.

[0121] Furthermore, in the case of the curved pattern image group a6 as shown in FIG. 8(a), a complex dynamic visual effect can be obtained in which the reflected light changes its shape and moves within the image group a6 as the viewing direction is continuously shifted, as shown in FIG. 8(b) to (e).

[0122] As described above, the printed matter 1 according to this embodiment has reflection characteristics in which reflected light is invisible when the viewing direction and the orientation direction of the object a are parallel, and reflected light is most intense when the viewing direction and the orientation direction of the object a are perpendicular, and thus can produce a latent image that changes in a complex manner with a metallic gloss as the viewing direction from the observer 70 and the direction of the incoming light I from the light source 60 change. Since it is extremely difficult to reproduce such a dynamic visual effect, the printed matter 1 according to this embodiment has excellent counterfeit resistance.

[0123] Moreover, the display of such a glossy latent image is obtained using ordinary color inks as an optical change resulting from the structure of two or more image groups, and does not depend on the optical properties of the functional material contained in the ink. Therefore, even if the pigment manufacturer does not sell a functional material that can achieve the effect, it can be easily achieved by using this printed matter, which has the effect of improving the freedom of color design.

[0124] Furthermore, with the printed matter 1 according to this embodiment, a latent image can be expressed with a wide range of changes, from simple changes to more complex and dynamic changes, simply by changing the composition of the image lines. Also, the printed matter 1 according to this embodiment does not require a dedicated production device or machine, and can be produced using an existing printing machine, so it is also excellent in cost performance.

[0125] When determining whether the printed matter 1 is genuine, the printed matter 1 is rotated while the printed surface on which the image line a is printed faces the light source 60, and a latent image appears on the printed surface in a predetermined pattern, which can be visually confirmed and the genuineness of the printed matter 1 can be easily determined on the spot without the need for special tools.

[0126] If it is a counterfeit product, even if it is rotated with the printed surface facing the light source 60, the latent image will not appear in the predetermined pattern, so it can be determined that it is a counterfeit product.

[0127] For example, consider a case in which white light is shone onto a genuine printed matter 1 from a position directly facing it, light reflected from the printed matter 1 is received, scan data corresponding to the image data is output to a processing unit, the processing unit generates print data from this scan data, and a printer unit prints based on the print data, thereby creating a counterfeit copied image.

[0128] In this case, the white light is applied as parallel light from a directly opposed position, so the image lines (a0, a1, a2, a3, a4, a5, a6) in the genuine printed matter 1 are all read and copied in the same state. Since this copied image is output in a solid printed state, even if the viewing direction is changed and the copied image is observed, the metallic luster as described above and the latent image are not expressed, so that it is possible to reliably determine that it is a counterfeit even if it is not obvious from the outside.

[0129] The optical effects associated with changes in the viewing direction or the direction of the light source 60, which are realized by the printed matter 1 according to this embodiment, cannot be reproduced even with the latest digital printing equipment. Therefore, this embodiment provides a technology that allows easy determination of authenticity by observation with the naked eye and makes counterfeiting difficult. Therefore, the printed matter 1 according to this embodiment can be suitably applied to security media that require anti-counterfeiting effects, such as banknotes, passports, securities, identification cards, cards, and travel tickets.

[0130] (Manufacturing method) Next, a method for producing a printed matter according to this embodiment will be described.

[0131] The printed matter 1 according to this embodiment is printed using a known printing method.

[0132] Therefore, printing methods include, but are not limited to, screen printing, screen offset printing, gravure printing, gravure offset printing, flexographic printing, and the like.

[0133] In addition, as the ink for forming image groups such as the first image group a0, the second image group a1, a2, a3, a4, the third image group a5, and the fourth image group a6, it is possible to use general-purpose inks such as oxidative polymerization inks, UV-curable inks, and photocurable resins.

[0134] Furthermore, pigments can also be used in the ink.

[0135] Specific pigments include, but are not limited to, metals, oxides such as titanium dioxide, zinc oxide, and iron oxide, hydroxides, sulfides, selenides, cobalt aluminate, ferrocyanides, chromates, sulfates, carbonates, silicates, phosphates, and carbon.

[0136] Specific organic pigments include, but are not limited to, carbon compounds, nitroso compounds, nitro compounds, azo compounds, lake pigments, phthalocyanine compounds, and condensed polycyclic materials.

[0137] The ink pigment may use light scattering particles.

[0138] Specific light scattering particles include, but are not limited to, acrylic resin, polystyrene, styrene-acrylic copolymer or crosslinked product thereof, melamine-formaldehyde condensate, urethane resin, polyester, silicone resin, fluorine particles, epoxy resin, and copolymers thereof.

[0139] Specific inorganic materials that can be used for the light scattering particles include, but are not limited to, clay compounds such as smectite, kaolinite, and talc; inorganic oxides such as silica, titania, alumina, silica alumina, zirconia, zinc oxide, barium oxide, and strontium oxide; inorganic carbonates such as calcium carbonate, barium carbonate, magnesium carbonate, and strontium carbonate; inorganic chlorides such as barium chloride and strontium chloride; inorganic sulfates such as barium sulfate and strontium sulfate; inorganic nitrates such as barium nitrate and strontium nitrate; inorganic hydroxides such as barium hydroxide, aluminum hydroxide, and strontium hydroxide; and glass.

[0140] The resin material can be appropriately mixed with solvents such as hydrocarbon solvents (petroleum naphtha, toluene, xylene, tetralin, turpentine oil, etc.), ester solvents (n-butyl acetate, methoxybutyl acetate, etc.), ketone solvents (MIBK, diacetone alcohol, cyclohexanone, isophorone, etc.), and polyhydric alcohol derivatives (methyl cellosolve, ethyl cellosolve, butyl cellosolve, cellosolve acetate, butyl cellosolve acetate, butyl carbitol, etc.).

[0141] Additives for the resin material are not limited, but may include vegetable oils, surfactants, wax swelling bodies, defoamers, leveling agents, slip agents, UV absorbers, plasticizers, curing accelerators, etc., which may be mixed appropriately. EXAMPLES

[0142] Next, examples of actually producing printed matter according to the embodiment of the present invention will be described below as examples.

[0143] FIG. 9 is a conceptual diagram showing the principle of a printing device applied to printing of a printed matter according to an embodiment of the present invention.

[0144] The printing apparatus may be a gravure offset printing apparatus 100 .

[0145] The gravure offset printing apparatus 100 includes a printing plate 101 made of an intaglio plate, a blanket 103 for ink transfer wrapped around a blanket cylinder 102, a doctor 106 for filling the printing plate 101 with ink 105, and a printing platen 111.

[0146] The printing plate 101 used was a metal flat plate measuring 100 mm wide x 100 mm long, with print pattern grooves 104 engraved by etching in the areas that would become the image lines.

[0147] Examples of image groups include a first image group a0, a second image group a1, a2, a3, a4, a third image group a5, and a fourth image group a6 shown in FIG.

[0148] In the first image group a0, the images a were arranged in a line pattern with a line width w of 0.03 mm, a gap s of 0.03 mm, and an orientation direction of 135°.

[0149] In the second image groups a1, a2, a3, and a4, the image groups a are also arranged in a line pattern with a line width w of 0.03 mm and a gap s of 0.03 mm. Although the line width w and gap s are the same, the orientation directions are different: 90° for image group a1, 0° for image group a2, 45° for image group a3, and 135° for image group a4.

[0150] In the third image group a5, the images a were arranged concentrically, with a line width w of 0.03 mm and a gap s of 0.03 mm.

[0151] In the fourth image group a6, the images a were arranged in a curved line, the line width w was 0.03 mm, and the gap s was 0.03 mm.

[0152] The blanket cylinder 102 was made of SUS304 and had a cylinder width of 220 mm and a diameter of 300 mm.

[0153] On the surface of the blanket cylinder 102, a blanket 103 made of a material mainly composed of silicone rubber, having a thickness of 0.9 mm, a hardness of 20°, a width of 200 mm and a length of 250 mm is fixed.

[0154] The blanket cylinder 102 is supported on a movable carriage (not shown), which is further supported on a platform (not shown).

[0155] The blanket cylinder 102 rolls the blanket 103 while pressing it against the printing plate 101, so that the ink 107 in the printing pattern grooves 104, which are recesses of the printing plate 101, is received on the surface of the blanket 103 as shown as ink 108. Thereafter, the blanket cylinder 102 then rolls the blanket 103 while pressing it against the printing substrate 110, so that the ink 108 is transferred to the surface of the printing substrate 110 as ink 109.

[0156] The printing substrate 110 was made of a transparent polyethylene terephthalate (PET) film measuring 150 mm wide x 150 mm long x 0.01 mm thick.

[0157] In this manner, the gravure offset printing apparatus 100 printed and formed the image groups a0 to a6 on the surface of the printing substrate 110. The image groups a0 to a6 were formed using cyan ink, which is a typical ink for offset printing.

[0158] Next, the process of printing a printed matter using such a printing device will be described in detail with reference to FIG.

[0159] FIG. 10 is a diagram showing each process up to when a printed matter is printed by the printing device shown in FIG.

[0160] First, as shown in FIG. 10(a), cyan ink 105 is applied to a printing plate 101 at a concentration of 0.5 g / cm 2 was supplied.

[0161] Next, as shown in FIG. 10(b), the position where the doctor 106 and the printing plate 101 contacted was set as the zero point of the doctor 106, and the doctor 106 was used to fill the printing pattern grooves 104 with ink 107 while scraping off the ink 105 at a position 0.5 mm closer to the printing plate 101 in the longitudinal direction from this zero point.

[0162] 10(c), the position where the printing plate 101 and blanket 103 come into contact is defined as the zero point of the blanket cylinder 102, and the position where the blanket cylinder 102 is moved 0.5 mm closer to the printing plate 101 from this zero point is defined as the position where the filled ink 107 of the printing plate 101 is received by the blanket 103, and the blanket cylinder 102 is rolled at a speed of 50 mm / sec at this position, so that the filled ink 107 of the printing plate 101 is received by the blanket 103. The received ink 107 is shown as ink 108 in FIG. 10(c).

[0163] Finally, as shown in Fig. 10(d), the position where the printing substrate 110 and the blanket 103 come into contact is set as the zero point of the blanket cylinder 102, and the position where the blanket cylinder 102 is moved 0.5 mm closer to the printing substrate 110 from this zero point is set as the position where the ink 108 received by the blanket 103 is transferred to the printing substrate 110, and the blanket cylinder 102 is rolled at a speed of 100 mm / sec at this position to transfer the ink 108 received by the blanket 103 to the printing substrate 110. The transferred ink 108 is shown as ink 109 in Fig. 10(d).

[0164] In this manner, printing of the image groups a0 to a6 on the printing substrate 110 is completed, and the printed matter 1 as shown in FIG. 1 is obtained.

[0165] Although the best mode for carrying out the present invention has been described above with reference to the attached drawings, the present invention is not limited to such a configuration. Within the scope of the technical idea of ​​the invention defined in the claims, a person skilled in the art may conceive of various modifications and alterations, and it is understood that such modifications and alterations also belong to the technical scope of the present invention. [Explanation of symbols]

[0166] 1,1a,1b,1c,1d Printed matter 2 Printing base material 50 Traditional Print 60 light source 70 Observer 100 Gravure offset printing equipment 101 Print Edition 102 Blanket Torso 103 Blanket 104 Printing pattern groove 105 Ink (supplied ink) 106 Doctor 107 Ink (filled ink) 108 Ink (Accepted Ink) 109 Ink (transferred ink) 110 Printing base material 111 Printing plate a Stroke a0,a1,a2,a3,a4,a5,a6 line group b surface h Height h1,h3 minimum height h2 Maximum height I Light entering R Reflected light s gap w Line width

Claims

1. A printed matter having a plurality of image lines printed on a printing substrate, The height of each of the plurality of image lines from the printing substrate is maximum at a center portion in a line width perpendicular to an orientation direction and is minimum at both ends in the line width, Each of the plurality of image lines has a cross-sectional shape that rises from both ends toward the center in a line width direction, each of the plurality of image lines belongs to any one of a plurality of image line groups each including image lines having the same gap between adjacent image lines in the line width direction, the same line width, and the same orientation direction; The printed matter, wherein the plurality of image groups includes at least one image group having an orientation direction different from the other image groups.

2. The line width is greater than 0.0 mm and less than or equal to 0.5 mm; The height from the printing substrate at the central portion is greater than 0.0 mm and is equal to or less than 0.01 mm; The cross-sectional shape is an arc shape having the highest point at the center and the lowest point at both ends. The printed matter according to claim 1.

3. In each group of images, the gap is equal to or greater than 0.0 mm and equal to or less than 0.5 mm. The printed matter according to claim 1.

4. Among the plurality of image groups, there is at least one image group having the same line width and the same gap as any one of the plurality of image groups, but having a different orientation direction. The printed matter according to claim 1.

5. Among the plurality of image lines, there is at least one image line that has the same orientation direction as any one of the plurality of image lines but is different from the image line in at least one of the line width and the gap. The printed matter according to claim 1.

6. Among the plurality of image groups, there is at least one image group in which the image groups are arranged in a line pattern, a curved pattern, a concentric circle pattern, or a pattern formed by a combination of any of these patterns. The printed matter according to claim 1.

7. a latent image is embedded, the latent image being determined based on the number of the plurality of image groups, the arrangement position and area of ​​each image group on the printing substrate, and the line width, gap, and orientation direction of the image in each image group; The printed matter according to claim 1.

8. The image is formed with a transparent or opaque ink. The printed matter according to claim 7.

9. Among the plurality of image groups, there is at least one image group in which all the image groups are formed with ink of the same color. The printed matter according to claim 8.

10. Among the plurality of image lines, there is at least one image line group including image lines formed with inks of different colors. The printed matter according to claim 8.

11. imparting gloss and hue to the latent image by a combination of different colors in the image group including the image lines formed with inks of different colors; The printed matter according to claim 10.

12. A method for determining authenticity of a printed matter according to claim 1, comprising: The authenticity determination method comprises: rotating the printed matter while keeping the printed surface side on which the image lines are printed facing an illumination light from a fixed light source; and determining whether the printed matter is authentic or counterfeit based on an image appearing on the printed surface.

13. The method according to claim 12 , wherein the image changes in response to the print being rotated.

14. The authenticity determination method according to claim 13 , further comprising determining that the printed matter is authentic if the image changes in a predetermined manner in response to the rotation of the printed matter.

Images