Printed material, authenticity determination method, and authenticity determination device

Abstract

To provide a printed material that allows for low-cost production without causing image complexity, while delivering a high anti-counterfeiting effect.SOLUTION: A printed material comprises an image comprising a plurality of portions printed on a substrate with light reflectivity, wherein the plurality of portions are each printed with ink having different light reflection properties.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to printed matter with security measures in place to prevent counterfeiting, such as securities such as bonds, checks, gift certificates, lottery tickets, and commuter passes, and to an apparatus and method for determining the authenticity of such printed matter. [Background technology]

[0002] Conventionally, securities such as bonds, checks, gift certificates, lottery tickets, and commuter passes often have machine-readable code marks such as barcodes and OCR characters. This machine-readable information is formed, for example, by using ink that absorbs infrared rays in the near-infrared region, such as carbon black, on the surface of a base material that reflects infrared rays in the near-infrared region.

[0003] In some cases, machine-readable information is printed on the securities as a bar code pattern code mark by utilizing the infrared reflectivity of white ink and the infrared absorptivity of black ink.

[0004] For securities having such a code mark, the code mark is read by irradiating the portion of the code mark with infrared rays and measuring the reflection intensity of the infrared rays reflected from that portion. In such cases, generally, in order to prevent unauthorized reading of the recorded information, a concealing layer that blocks visible light and transmits infrared rays is provided to cover the information, so that the information cannot be easily read visually under irradiation with visible light.

[0005] However, since infrared absorbing substances such as carbon black have light absorbing properties even in the visible light region, even if a concealing layer is formed, the information concealing locations can be identified at a glance, and the concealed information pattern can be easily mechanically read by an infrared information reading device, so that these substances remain insufficient as an effective means of preventing counterfeiting or alteration using copying, etc. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2006-213017 A [Patent Document 2] JP 2005-246719 A Summary of the Invention [Problem to be solved by the invention]

[0007] To solve the above problems, there is a technology in which code marks, etc. are printed using two or more types of infrared-absorbing printing ink or infrared-transparent printing ink with different spectral characteristics, and the image printed with the infrared-transparent printing ink is captured on a single black-and-white screen using two or more types of light sources or filters, and each image on the screen is read to determine authenticity.

[0008] However, when a code mark or the like is printed using two or more types of infrared-absorbing printing inks or infrared-transparent printing inks with different spectral characteristics and the image printed with the infrared-absorbing printing inks or infrared-transparent printing inks is captured on a single black-and-white screen to determine its authenticity, each of the images captured on the single screen must be read to determine its authenticity, which makes the image complicated and makes determining the authenticity extremely difficult.

[0009] Another method to solve the above problem is to print code marks, etc., using two or more types of infrared-absorbing printing inks with different spectral characteristics, and capture the images printed with the infrared-absorbing printing inks as a single color image to determine authenticity. However, with this authenticity determination technology, the concealed image can be faintly seen when observed under visible light, which can unintentionally damage the appearance. Images visible under visible light can be concealed by combining them with a medium, etc., but this has the disadvantage of being expensive.

[0010] The present invention has been made in consideration of the above circumstances, and aims to provide a printed matter with high anti-counterfeiting effect that can be produced at low cost without complicating the image, and an authenticity determination method and authenticity determination device that can reliably determine the authenticity of the printed matter. [Means for solving the problem]

[0011] In order to achieve the above object, the present invention takes the following measures.

[0012] The first aspect is a printed matter in which an image comprising multiple parts is printed on a light-reflective substrate, and each of the multiple parts is printed with an ink having different light-reflecting properties.

[0013] A second aspect is a printed matter of the first aspect, wherein the multiple portions include a first portion printed with a first ink and a second portion printed with a second ink different from the first ink, the first ink having a light reflectance higher than a predetermined value at a first wavelength or greater, the second ink having a light reflectance higher than a predetermined value at a second wavelength or greater, and the second wavelength being longer than the first wavelength.

[0014] A third aspect is a printed matter of the second aspect, wherein the plurality of portions further includes an Nth portion printed with an Nth ink, where N is an integer greater than or equal to 3, the Nth ink is different from any of the first through (N-1)th inks, the Nth ink has a light reflectance greater than a predetermined value at or above the Nth wavelength, and the Nth wavelength is longer than the (N-1)th wavelength.

[0015] A fourth aspect is a printed matter of the first aspect, in which the multiple portions include black portions (carbon black) printed with black ink and a first portion printed with a first ink different from the black ink, and the first ink has a light reflectance higher than a predetermined value that is higher than the light reflectance of the black ink at a first wavelength or longer.

[0016] A fifth aspect is a printed matter of the fourth aspect, wherein the plurality of portions further includes a second portion printed with a second ink different from both the black ink and the first ink, the second ink having a light reflectance higher than a predetermined value at or above a second wavelength, and the second wavelength being longer than the first wavelength.

[0017] A sixth aspect is a printed matter of the fifth aspect, wherein the plurality of portions further includes an Nth portion printed with an Nth ink, where N is an integer greater than or equal to 3, the Nth ink is different from any of the first through (N-1)th inks, the Nth ink has a light reflectance greater than a predetermined value at or above the Nth wavelength, and the Nth wavelength is longer than the (N-1)th wavelength.

[0018] A seventh aspect is the printed matter of the third aspect or the sixth aspect, in which, when irradiated with light, the light reflected from the first portion is brighter when the light is equal to or greater than the first wavelength than when the light is less than the first wavelength, the light reflected from the (N-1)th portion is brighter when the light is equal to or greater than the (N-1)th wavelength than when the light is less than the (N-1)th wavelength, and the light reflected from the Nth portion is brighter when the light is equal to or greater than the Nth wavelength than when the light is less than the Nth wavelength.

[0019] An eighth aspect is the printed matter of the seventh aspect, in which the visible light region is included in a wavelength region less than the first wavelength, and the first wavelength to the Nth wavelength are included in the infrared region.

[0020] A ninth aspect is a method for determining the authenticity of a printed matter of the third or sixth aspect, which involves irradiating light onto the printed matter, and identifying as the first part a portion where the reflected light from the printed matter is brighter when the reflected light is equal to or greater than the first wavelength than when the reflected light is less than the first wavelength, identifying as the (N-1)th part a portion where the reflected light is brighter when the reflected light is equal to or greater than the (N-1)th wavelength than when the reflected light is less than the (N-1)th wavelength, and identifying as the Nth part a portion where the reflected light is brighter when the reflected light is equal to or greater than the Nth wavelength than when the reflected light is less than the Nth wavelength, thereby identifying each of the first through Nth parts, and determining the authenticity of the printed matter based on the identification results.

[0021] A tenth aspect is a method for determining authenticity of the ninth aspect, in which, instead of determining the authenticity of the printed matter based on the identification results, each of the identified parts 1 through N is colored with a specified color and an image combining the colored parts is displayed.

[0022] An eleventh aspect is a device for determining authenticity of a printed matter of the third or sixth aspect, comprising a light source for illuminating the printed matter, N filters numbered from 1st to Nth, N imaging units numbered from 1st to Nth, an identification unit, and a determination unit, wherein the first filter removes light components less than a first wavelength from reflected light from the printed matter illuminated by the light source, the (N-1)th filter removes light components less than the (N-1)th wavelength from the reflected light, the Nth filter removes light components less than the Nth wavelength from the reflected light, the first imaging unit captures the light components that have passed through the first filter to obtain a first reflected image, and the (N-1)th imaging unit captures the light components that have passed through the (N-1)th filter to obtain a first reflected image. an Nth imaging unit captures the light component that has passed through the Nth filter to obtain an (N-1)th reflected image, an Nth imaging unit captures the light component that has passed through the Nth filter to obtain an Nth reflected image, an identification unit identifies a portion that appears brighter than other portions in the first reflected image as a first portion, a portion other than the (N-2)th or earlier portion that appears brighter than other portions in the (N-1)th reflected image as a (N-1)th portion, and a portion other than the (N-1)th or earlier portion that appears brighter than other portions in the Nth reflected image as a Nth portion, and a determination unit determines the authenticity of the printed matter based on the identification result by the determination unit.

[0023] A twelfth aspect is a printed matter authenticity determination device of the third or sixth aspect, comprising N types of light sources from 1st to Nth, an imaging unit, an identification unit, and a determination unit, wherein the first light source illuminates the printed matter with light of a first wavelength or more, the (N-1)th light source illuminates the printed matter with light of the (N-1)th wavelength or more, and the Nth light source illuminates the printed matter with light of the Nth wavelength or more, the imaging unit images the first reflected light reflected from the printed matter illuminated by the first light source to obtain a first reflected image, and images the (N-1)th reflected light reflected from the printed matter illuminated by the (N-1)th light source to obtain an (N-1)th reflected image. an identification unit identifies a portion that appears brighter than other portions in the first reflection image as the first portion, a portion other than portions prior to (N-2) that appears brighter than other portions in the (N-1) reflection image as the (N-1) portion, and a portion other than portions prior to (N-1) that appears brighter than other portions in the Nth reflection image as the Nth portion; and a determination unit determines the authenticity of the print based on the identification result by the determination unit.

[0024] A thirteenth aspect is an authenticity determination device of the eleventh aspect, which further includes a coloring unit, instead of a determination unit, that colors each of the first through Nth parts in a different color, and a display control unit that displays an image combining each of the parts colored by the coloring unit.

[0025] A fourteenth aspect is an authenticity determination device of the twelfth aspect, which further includes a coloring unit, instead of a determination unit, that colors each of the first through Nth parts in a different color, and a display control unit that displays an image combining each of the parts colored by the coloring unit. Effect of the Invention

[0026] According to the present invention, it is possible to realize a printed matter with high anti-counterfeiting effect that can be produced inexpensively without complicating the image, and an authenticity determination method and authenticity determination device that can reliably determine the authenticity of the printed matter. [Brief description of the drawings]

[0027] [Figure 1] FIG. 1 is a side cross-sectional view showing an example of a basic configuration of a printed matter according to an embodiment of the present invention. [Diagram 2] FIG. 2 is another cross-sectional side view showing an example of the basic configuration of a printed matter according to an embodiment of the present invention. [Diagram 3] FIG. 3 is a plan view showing an example of the printed matter shown in FIG. [Figure 4] FIG. 4 is a plan view showing an example of the printed matter shown in FIG. [Diagram 5] FIG. 5 is a diagram showing the reflectance characteristics versus wavelength of infrared reflective ink and black ink. [Figure 6] FIG. 6 is an enlarged view of the image in FIG. [Figure 7] FIG. 7 is a diagram showing an example of an image printed with carbon black. [Figure 8] FIG. 8 is a diagram showing an example of an image printed with the infrared reflective ink 1. [Figure 9] FIG. 9 is a diagram showing an example of an image printed with the infrared reflective ink 2. [Figure 10] FIG. 10 is a diagram showing an example of an image printed with the infrared reflective ink 3. [Figure 11] FIG. 11 is a diagram showing how each part of an image appears in each wavelength region. [Figure 12] FIG. 12 is a configuration diagram showing a first example of an authenticity determination device to which the authenticity determination method according to an embodiment of the present invention is applied. [Figure 13] FIG. 13 is a configuration diagram showing a second example of an authenticity determination device to which the authenticity determination method according to an embodiment of the present invention is applied. [Figure 14] FIG. 14 is a configuration diagram showing a modified example of the processing computer. [Figure 15] FIG. 15 is a diagram showing an example of a composite image in which different parts are colored with different colors. [Figure 16]FIG. 16 is a diagram showing an example of a composite image when two colors, one type of infrared reflective ink and carbon black, are used. [Figure 17] FIG. 17 is a plan view showing an image of a security print created as an example of a printed matter observed under visible light. [Figure 18] FIG. 18 is a plan view showing an image observed under infrared irradiation of the security print shown in FIG. [Figure 19] FIG. 19 is a perspective view showing an example of how a counterfeit security print appears. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. The drawings are schematic or conceptual, and the relationship between the thickness and width of each part, the size ratio between parts, etc. are not necessarily the same as the actual ones. Even when the same part is shown, the dimensions and ratios of each part may be different depending on the drawing. In this specification and each drawing, elements similar to those described above with respect to the previous drawings are given the same reference numerals, and detailed explanations and duplicated explanations are omitted as appropriate.

[0029] (Printed material) FIG. 1 is a side cross-sectional view showing an example of a basic configuration of a printed matter according to an embodiment of the present invention.

[0030] FIG. 2 is another cross-sectional side view showing an example of the basic configuration of a printed matter according to an embodiment of the present invention.

[0031] 1 and 2, the printed matter 10 has an image 12 including a plurality of parts printed on a light-reflective substrate 11. The light-reflective substrate 11 may be an infrared-reflective substrate 11. Therefore, in the following description, the substrate 11 will be described as an infrared-reflective substrate 11 as an example.

[0032] Furthermore, in the printed matter 10, the multiple portions that make up the image 12 are printed using multiple types of ink that have different light reflection characteristics.

[0033] As the multiple types of inks having different light reflecting properties, four types of inks can be used, as shown in Figure 1, consisting of infrared reflective inks 1, 2, and 3, and black ink 0. Black ink 0 can be, for example, carbon black.

[0034] As another example of multiple types of ink, two types of ink may be used, an infrared reflective ink 1 and a black ink 0, as shown in FIG.

[0035] Also, since black ink 0 is not essential, another example of multiple types of inks could be three types of ink consisting of infrared reflective inks 1, 2, and 3, without using black ink 0. Alternatively, yet another example of multiple types of inks could be two types of ink consisting of infrared reflective inks 1 and 2.

[0036] Furthermore, as an example of multiple types of ink, four or more types of infrared reflective inks may be used, with or without black ink 0.

[0037] FIG. 3 is a plan view showing an example of the printed matter shown in FIG.

[0038] FIG. 4 is a plan view showing an example of the printed matter shown in FIG.

[0039] FIG. 3 shows a picture of an image 12 printed with infrared reflective inks 1, 2, 3 and black ink 0 on an infrared reflective substrate 11 as in FIG.

[0040] FIG. 4 shows a picture of an image 12 printed with infrared reflective ink 1 and black ink 0 on an infrared reflective substrate 11 as in FIG.

[0041] As illustrated in FIGS. 3 and 4, the printed matter 10 may have characters 14 printed in black ink, for example, in a location separate from the image 12.

[0042] Next, the characteristics of the ink will be described.

[0043] FIG. 5 is a graph showing the reflectance characteristics versus wavelength for infrared reflective inks 1, 2, and 3 and black ink 0, with the horizontal axis representing wavelength (nm) and the vertical axis representing reflectance (%).

[0044] The reflectance of black ink 0 increases slightly with wavelength in the wavelength range shown in FIG. 5, but is generally low and does not exceed 20%.

[0045] On the other hand, the reflectance of infrared reflective ink 1, in the wavelength range shown in Figure 5, is as low as that of black ink 0 on the low wavelength side, but rises sharply at a wavelength just before 700 (nm) (first wavelength), increasing to about 80 (%), and then remains at about 80 (%) with almost no change.

[0046] In the wavelength range shown in Figure 5, the reflectance of infrared reflective ink 2 is as low as that of black ink 0 on the low wavelength side, but it rises sharply at wavelengths above 700 (nm) (second wavelength), increasing to about 80 (%), and then remains at about 80 (%) with almost no change.

[0047] In the wavelength range shown in Figure 5, the reflectance of infrared reflective ink 3 is as low as that of black ink 0 on the low wavelength side, but exceeds 700 (nm) and rises sharply at wavelengths (third wavelength) longer than the wavelength (second wavelength) at which infrared reflective ink 2 shows a rise, increasing to about 80 (%), after which it hardly changes, remaining at about 80 (%).

[0048] Thus, the reflectance of infrared reflective inks 1, 2, and 3 all have low values ​​in the visible light region, similar to that of black ink 0, but in the infrared region, they rise sharply at a certain wavelength and become significantly greater than the reflectance of black ink 0. The wavelengths at which this rise occurs are clearly different for infrared reflective inks 1, 2, and 3, and in the example shown in Figure 5, from the short wavelength side, the reflectance of infrared reflective ink 1 first rises at a first wavelength just before 700 (nm), then the reflectance of infrared reflective ink 2 rises at a second wavelength exceeding 700 (nm), and then the reflectance of infrared reflective ink 3 rises at a third wavelength on the longer wavelength side.

[0049] There is no limit to the number of types of infrared reflective inks that can be used, so long as each of the infrared reflective inks has the property that the reflectance rises sharply at wavelengths different from each other.

[0050] For example, consider a case where it is desired to use a fourth type of infrared reflective ink in addition to infrared reflective inks 1, 2, and 3. In this case, if the fourth type of infrared reflective ink has a reflectance characteristic of having a low reflectance on the low wavelength side, but a wavelength (fourth wavelength) that shows a sharp rise in reflectance on the longer wavelength side than the third wavelength in the infrared region, such a fourth type of infrared reflective ink can be used. Similarly, a fifth type of infrared reflective ink can be used if it has a reflectance characteristic of having a low reflectance on the low wavelength side, but a wavelength (fifth wavelength) that shows a sharp rise in reflectance on the longer wavelength side than the fourth wavelength in the infrared region. In this way, the number of types of infrared reflective inks that can be used can be increased.

[0051] FIG. 6 is an enlarged view of image 12 in FIG.

[0052] Image 12 is printed using black ink 0 and infrared reflective inks 1, 2, and 3, as shown in Figure 1. In other words, image 12 is formed by combining an image printed with black ink 0, an image printed with infrared reflective ink 1, an image printed with infrared reflective ink 2, and an image printed with infrared reflective ink 3.

[0053] Examples of images printed with each of these inks are shown in Figures 7, 8, 9, and 10. As mentioned above, black ink 0 can be carbon black, so in the following description, black ink 0 will also be referred to as carbon black 0.

[0054] FIG. 7 shows an image 12(0) printed with carbon black 0, FIG. 8 shows an image 12(1) of a portion (first portion) 13(1) printed with infrared reflective ink 1, FIG. 9 shows an image 12(2) of a portion (second portion) 13(2) printed with infrared reflective ink 2, and FIG. 10 shows an image 12(3) of a portion (third portion) 13(3) printed with infrared reflective ink 3.

[0055] As shown in Figure 6, image 12 shows cherries, bananas, and apples lined up close together, while Figure 7 shows image 12(0) of portion 13(0) of that state, which is represented by a line drawing using carbon black 0. Incidentally, portions printed with carbon black 0, which absorbs all wavelengths in the infrared range, are visible in all images in the infrared range. Therefore, as shown in Figure 7, it is possible to extract a reflected image of verification image 12(0) that is concealed in printed matter 10.

[0056] Also, Fig. 8 shows an image 12(1) of a first portion 13(1) showing cherries filled in with infrared reflective ink 1, Fig. 9 shows an image 12(2) of a second portion 13(2) showing a banana filled in with infrared reflective ink 2, and Fig. 10 shows an image 12(3) of a third portion 13(3) showing an apple filled in with infrared reflective ink 3. The infrared reflective inks 1, 2, and 3 also have low reflectance in the visible light region and therefore appear black due to the reflected light.

[0057] Image 12 shown in Figure 6 is a composite of these images 12(0),(1),(2), and (3). Image 12 has a low reflectance in the visible light region α as shown in Figure 11(a), and therefore appears black due to reflected light as shown in Figure 11(b).

[0058] However, when the wavelength of the reflected light is in region β, which is equal to or greater than the first wavelength in the infrared region, the reflectance of first portion 13(1) representing the cherry increases, and the reflected light from first portion 13(1) becomes brighter than when the wavelength is less than the first wavelength, that is, in the visible light region α. ​​As a result, the cherry appears white, as shown in Figure 11(c).

[0059] When the wavelength of the reflected light becomes higher and enters a region γ that is equal to or greater than the second wavelength in the infrared region, the reflectance of second portion 13(2) representing the banana increases, and the reflected light from second portion 13(2) becomes brighter than in region β, which is less than the second wavelength. As a result, in addition to the cherries, the banana also appears white, as shown in Figure 11(d).

[0060] When the wavelength of the reflected light becomes higher and enters region δ that is equal to or greater than the third wavelength in the infrared region, the reflectance of third portion 13(3) representing the apple increases, and the reflected light from third portion 13(3) becomes brighter than in region γ that is less than the third wavelength. As a result, the apple, in addition to the cherries and bananas, appears white, as shown in Figure 11(e).

[0061] By utilizing this characteristic, it is possible to determine the authenticity of a printed matter. Below, a method and an apparatus for performing authenticity determination using this characteristic will be described.

[0062] (Authenticity determination method and authenticity determination device) (First example) FIG. 12 is a configuration diagram showing a first example of an authenticity determination device to which the authenticity determination method according to an embodiment of the present invention is applied.

[0063] This authenticity determination device 30 is a device for determining the authenticity of a printed matter 10, and is equipped with an infrared irradiation light source 31 that illuminates the printed matter 10, N (in this example, three because the number of infrared reflective inks used in the printed matter 10 is three) cut filters 51-53, N-1 (in this example, two) beam splitters 54-55, N (in this example, three) imaging units 41-43, and a processing computer 60.

[0064] The processing computer 60 can be realized by a PC, a mobile terminal, etc., and although a detailed description of the hardware configuration is omitted, the receiving unit 61, the identifying unit 62, the determining unit 63, and the display control unit 64 are realized by cooperation between a processor and software. The receiving unit 61, the identifying unit 62, the determining unit 63, and the display control unit 64 are connected to one another via a bus 66. A display 65 is connected to the display control unit 64.

[0065] The infrared irradiating light source 31 irradiates the printed matter 10 with infrared rays. A portion of the infrared rays irradiating the printed matter 10 is reflected by the printed matter 10 and becomes reflected light R. The reflected light R is guided to the beam splitter 54. Since the higher the intensity of the reflected light R, the higher the accuracy of the authenticity determination, it is preferable to have a plurality of infrared irradiating light sources 31. Note that the number of infrared irradiating light sources 31 is not related to the number of infrared reflective inks used on the printed matter 10.

[0066] The beam splitter 54 is a 30R / 70T type beam splitter that reflects 30% of the reflected light R and transmits 70% of the reflected light R. Light R1, which is 30% of the reflected light R reflected by the beam splitter 54, is guided to the cut filter 51, and light R2, which is 70% of the reflected light R that transmits the beam splitter 54, is guided to the beam splitter 55.

[0067] The beam splitter 55 is a 50R / 50T type beam splitter that reflects 50% of the light R2 and transmits 50% of the light R2. Light R3, which is 50% of the light R2 reflected by the beam splitter 55, is guided to the cut filter 52, and light R4, which is 50% of the light R2 that transmits through the beam splitter 55, is guided to the cut filter 53. In this way, the reflected light R is split by the number of cut filters, that is, in this example, it is split into three, light R1, R2, and R3, and each of R1, R2, and R3 is guided to the cut filters 51, 52, and 53, respectively.

[0068] The cut filter 51 is a bandpass filter that removes light components less than a first wavelength from the light R1. As a result, the light R11 that passes through the cut filter 51 becomes light having a wavelength equal to or greater than the first wavelength, that is, light having a wavelength longer than that of the region α. ​​The light R11 is guided to the imaging unit 41.

[0069] The cut filter 52 is a bandpass filter that removes light components less than the second wavelength from the light R3. As a result, the light R31 that passes through the cut filter 52 becomes light having a wavelength equal to or greater than the second wavelength, that is, light having a wavelength longer than the region β. The light R31 is guided to the imaging unit 42.

[0070] The cut filter 53 is a bandpass filter that removes light components less than the third wavelength from the light R4. As a result, the light R41 that passes through the cut filter 53 becomes light having a wavelength equal to or greater than the third wavelength, that is, light having a wavelength longer than the region γ. The light R41 is guided to the imaging unit 43.

[0071] The imaging section 41 captures light R11, which is a light component that has passed through the band-pass filter 51, to obtain a first reflected image (for example, an image as shown in FIG. 11(c)).

[0072] The imaging section 42 captures the light R31 that is the light component that has passed through the band-pass filter 52, and obtains a second reflected image (for example, the image illustrated in FIG. 11(d)).

[0073] The imaging section 43 captures the light R41 that is the light component that has passed through the band-pass filter 53, and obtains a third reflected image (for example, an image as shown in FIG. 11(e)).

[0074] The first to third reflected images acquired by the imaging sections 41 to 43 are output from each of the imaging sections 41 to 43 to the processing computer 60 and received by the receiving section 61 of the processing computer 60.

[0075] The receiving unit 61 outputs the received first to third reflection images to the identifying unit 62 and the display control unit 64. As a result, the display control unit 64 causes the display 65 to display a first reflection image as shown in Fig. 11(c), a second reflection image as shown in Fig. 11(d), and a third reflection image as shown in Fig. 11(e).

[0076] On the other hand, the identification unit 62 identifies the portion 13(1) (cherries) that appears brighter than the other portions in the first reflected image (FIG. 11(c)) as the first portion. The identification unit 62 also identifies the portion 13(2) (banana) other than the first portion (cherries) that appears brighter than the other portions in the second reflected image (FIG. 11(d)) as the second portion. The identification unit 62 further identifies the portion 13(3) (apple) other than the portions before the second (cherries and banana) that appears brighter than the other portions in the third reflected image (FIG. 11(e)) as the third portion. These identification results are output from the identification unit 62 to the determination unit 63.

[0077] The identification result obtained by using an authentic printed matter 10 is known in advance. Therefore, the determination unit 63 determines the authenticity of the printed matter 10 based on the identification result by the identification unit 62. That is, if each of the portions 13(1)-(3) is correctly identified as known in advance, it is determined that the printed matter 10 is authentic.

[0078] On the other hand, when a counterfeit print is judged by the authenticity determination device 30, each of the portions 13(1) to (3) is not correctly identified, and therefore the print is judged to be not authentic.

[0079] (Second example) FIG. 13 is a configuration diagram showing an example of a second example of an authenticity determination device to which the authenticity determination method according to an embodiment of the present invention is applied.

[0080] This authenticity determination device 30A is a device for determining the authenticity of a printed matter 10, and is equipped with N types of infrared irradiation light sources 35-37 (in this example, three types because the number of infrared reflective inks used in the printed matter 10 is three) that illuminate the printed matter 10, a visible light range cut filter 32, an imaging unit 33, and a processing computer 60.

[0081] The processing computer 60 has the same configuration as that explained in FIG. 12, and therefore the explanation will be omitted.

[0082] The first type light source 35 illuminates the printed matter 10 with light having a first wavelength or longer, that is, light having a longer wavelength than the region α. ​​A portion of this light that illuminates the printed matter 10 is reflected by the printed matter 10 and becomes reflected light r1.

[0083] The second type light source 36 illuminates the printed matter 10 with light having a second wavelength or longer, that is, light having a longer wavelength than the region β. A portion of this light that illuminates the printed matter 10 is reflected by the printed matter 10 and becomes reflected light r2.

[0084] The third type light source 37 illuminates the printed matter 10 with light having a third wavelength or more, that is, light having a wavelength longer than that of the region γ. A part of this light that illuminates the printed matter 10 is reflected by the printed matter 10 and becomes reflected light r3.

[0085] These reflected lights r1, r2, and r3 are all guided to the visible light region cut filter 32.

[0086] The visible light region cut filter 32 removes the components of the visible light region α from the reflected light r1, r2, and r3. As a result, light r11 on the longer wavelength side than the region α, which is equal to or longer than the first wavelength obtained by removing the components of the visible light region from the reflected light r1, light r12 on the longer wavelength side than the region β, which is equal to or longer than the second wavelength obtained by removing the components of the visible light region from the reflected light r2, and light r13 on the longer wavelength side than the region γ, which is equal to or longer than the third wavelength obtained by removing the components of the visible light region from the reflected light r3, are guided to the imaging unit 33.

[0087] The imaging section 33 captures the light r11 to obtain a first reflected image, captures the light r12 to obtain a second reflected image, and captures the light r13 to obtain a third reflected image.

[0088] The first to third reflected images acquired by the imaging section 33 are output from the imaging section 33 to the processing computer 60 and received by the receiving section 61 of the processing computer 60.

[0089] The configuration of the processing computer 60 is the same as that described using Fig. 12, and similarly to the first example, the determination unit 63 determines the authenticity of the printed matter 10 based on the identification result by the identification unit 62. That is, if each of the portions 13(1) to (3) is correctly identified as known in advance, it is determined that the printed matter 10 is authentic.

[0090] On the other hand, when a counterfeit print is judged by the authenticity determination device 30A, the portions 13(1) to (3) are not identified, and therefore the print is judged to be not authentic.

[0091] The authenticity determination device 30A of the second example has multiple types of light sources, but differs from the authenticity determination device 30 of the first example in that it does not have a beam splitter. However, like the authenticity determination device 30 of the first example, it can determine whether or not the printed matter 10 is authentic.

[0092] (Modification of processing computer) Next, a modified example of the processing computer will be described.

[0093] FIG. 14 is a configuration diagram showing a modified example of the processing computer.

[0094] The processing computer 60A shown in FIG. 14 is applied in place of the processing computer 60 in the authenticity determination device 30 of the first example and the authenticity determination device 30A of the second example.

[0095] The processing computer 60A differs from the processing computer 60 in that it includes a coloring unit 67 instead of the determination unit 63. Therefore, in the following, the coloring unit 67 will be described to avoid duplication.

[0096] That is, the coloring unit 67 subtracts the reflected image information captured on the long wavelength side from the reflected image information captured on the short wavelength side, assigns color information to the remaining portion, and synthesizes a color image, thereby coloring each of the portions 13(1) to (3) identified by the identification unit 62 in a different color.

[0097] To explain this with reference to Figure 15, for example, the coloring unit 67 colors the portion 13(1) identified by the identification unit 62 in red as shown in Figure 15(a), the portion 13(2) in yellow as shown in Figure 15(b), and the portion 13(3) in green as shown in Figure 15(c). Then, the display control unit 64 causes the display 65 to display an image 70 in which the portions 13(1) to (3) colored by the coloring unit 67 are combined.

[0098] The display control unit 64 then controls the display 65 to display an image formed by combining the parts colored by the coloring unit 67. By viewing the display 65 on which the color image thus visualized, colored, and synthesized is displayed, the verification images 12(1)-(3) made of the three types of infrared-transparent printing inks can be distinguished, and at the same time, viewing the synthesized color image makes it easy to determine the authenticity of the printed matter.

[0099] As described above, according to this modified example, by viewing the composite color image 70 on the display 65, the user can easily and correctly visually determine whether the printed matter 100 is authentic.

[0100] In this case, since the user can visually determine whether the printed matter is genuine or not, there is no need for the determination unit 63 included in the processing computer 60. In other words, since the processing computer 60A can omit the determination unit 63 configured by a complex program, the program configuration can be simplified.

[0101] To enhance security, it is desirable for printed matter to be printed with three or more types of infrared-transparent printing ink. However, even if only one type of infrared-reflective ink is used, it is possible to recognize it as a color image by using it in two colors with carbon black.

[0102] FIG. 16 is a diagram showing an example of a composite image when two colors, one type of infrared reflective ink and carbon black, are used.

[0103] Portion 13(1) shown in Figure 16(a) shows cherries, similar to portion 13(1) shown in Figure 8. Portion 13(1) is printed with infrared reflective ink 1. Meanwhile, portion 13(0) showing the stem of the cherry is printed with carbon black. In this case, in the visible light region, the entire portion appears black as shown in Figure 16(a), but at a first wavelength or longer, i.e., at wavelengths in region β, portion 12(1) appears bright as shown in Figure 16(b).

[0104] The identification unit 62 identifies that the brightly-appearing portion 13(1) (cherries) is the portion printed with the infrared reflective ink 1, and that the rest is the portion printed with carbon black.

[0105] Then, the coloring unit 67 colors the identified portion 13(1) red, as shown in FIG. 16(c), and the display control unit 64 displays the portion 13(1) colored red by the coloring unit 67 in combination with the portion 13(0) printed black with carbon black on the display 65.

[0106] By visually viewing the display 65 showing the color image 70 that has been visualized, colored, and synthesized in this manner, the user can easily and correctly determine the authenticity of even a verification image consisting of one type of infrared-transparent printing ink 1 and carbon black.

[0107] (Application to security printing) An example of application of the above-mentioned printed matter, the authenticity of which can be determined by visual inspection by a user, to a security print will be described.

[0108] FIG. 17 is a plan view showing an image of a security print created as an example of the print according to the embodiment described above, observed under visible light.

[0109] The security print 100 has a verification image 110 printed thereon using three types of infrared absorbing printing inks 1, 2, and 3, and carbon black 0.

[0110] This verification image 110 appears black under visible light and has the same appearance as other black inks, so it can be applied naturally to the security print 100.

[0111] As described above, the reflected image information of the verification image 110 is captured individually under visible light and three types of infrared irradiation, four types of reflected image information are obtained, two types of images are compared from the short wavelength region images, bright areas displayed as white are extracted, and designated color information is added to each bright area. The verification image 110 can be confirmed based on one color image obtained by synthesizing the four images obtained in this way.

[0112] FIG. 18 is a plan view showing an image observed under infrared irradiation of the security print shown in FIG.

[0113] In the image shown in FIG. 18, bright areas that are displayed as white are observed as compared to the image shown in FIG.

[0114] A user can view this image and determine that if it is displayed correctly, the security print 100 is genuine; if not, the user can determine that it is not genuine, i.e., a counterfeit.

[0115] In addition, to enhance security, it is desirable to use three or more types of infrared-transmissive printing inks for the verification image 110, but it is also acceptable to print at least one type each of carbon black and infrared-reflective ink, as this will allow it to be recognized as a color image.

[0116] As described above, according to this embodiment, a highly secure printed matter can be provided and its authenticity can be easily determined, so that the present invention can be suitably applied to the security print 110. Moreover, this authenticity determination can be achieved inexpensively without damaging the appearance of the printed matter.

[0117] FIG. 19 is a perspective view showing an example of how a counterfeit security print appears.

[0118] The counterfeit security print 101 shown in Figure 19 is printed only with infrared absorbing ink, without using carbon black. When such a counterfeit security print 101 is tilted under visible light, the printed image is unintentionally visible due to reflection, making it easy to identify as a counterfeit. Furthermore, if infrared absorbing printing ink is applied to characters, they cannot be recognized as a single word, which impairs the design.

[0119] 17, the printed matter according to the embodiment of the present invention can be seamlessly incorporated into the design of the security print 100, allowing the verification image to be added while maintaining the design. In addition, even if the verification image is added to characters, it can be recognized under visible light without any sense of incongruity.

[0120] 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]

[0121] 0 Black Ink 1,2,3 Infrared reflective ink 10 Printed matter 11 Infrared reflective substrate 12 images 13 parts 14 characters 30,30A authenticity determination device 31 Infrared irradiation light source 32 Visible light cut filter 33 Imaging unit 35,36,37 light source 41, 42, 43 Imaging section 51,52,53 Cut filters, bandpass filters 54,55 Beam splitter 60,60A Processing computer 61 Receiving section 62 Specific part 63 Judgment section 64 Display control section 65 Display 66 Bus 67 Coloring section 70 Color Images 100 Securities Printing 101 Counterfeit securities 110 Verification image

Claims

1. An image including a plurality of portions is printed on a light-reflective substrate, Each of the plurality of portions is printed with ink having different light reflectance characteristics. printed matter.

2. the plurality of portions include a first portion printed with a first ink and a second portion printed with a second ink different from the first ink; the first ink has a light reflectance higher than a predetermined value at a first wavelength or longer; the second ink has a light reflectance higher than the predetermined value at a second wavelength or longer; The second wavelength is longer than the first wavelength. The printed matter according to claim 1.

3. The plurality of portions further includes an Nth portion printed with an Nth ink, where N is an integer of 3 or more; The Nth ink is different from any of the first to (N-1)th inks, The Nth ink has a light reflectance higher than the predetermined value at an Nth wavelength or longer, The Nth wavelength is longer than the (N-1)th wavelength. The printed matter according to claim 2.

4. the plurality of portions include a black portion printed with black ink and a first portion printed with a first ink different from the black ink, the first ink has a light reflectance higher than a predetermined value, which is higher than the light reflectance of the black ink, at a first wavelength or longer; The printed matter according to claim 1.

5. the plurality of portions further includes a second portion printed with a second ink different from both the black ink and the first ink; the second ink has a light reflectance higher than the predetermined value at a second wavelength or longer; The second wavelength is longer than the first wavelength. The printed matter according to claim 4.

6. The plurality of portions further includes an Nth portion printed with an Nth ink, where N is an integer of 3 or more; The Nth ink is different from any of the first to (N-1)th inks, The Nth ink has a light reflectance higher than the predetermined value at an Nth wavelength or longer, The Nth wavelength is longer than the (N-1)th wavelength. The printed matter according to claim 5.

7. When exposed to light, the reflected light from the first portion is brighter when the reflected light is equal to or greater than the first wavelength than when the reflected light is less than the first wavelength; the reflected light from the (N-1) portion is brighter when the wavelength is equal to or greater than the (N-1) wavelength than when the wavelength is less than the (N-1) wavelength; the reflected light from the Nth portion is brighter when the reflected light has a wavelength equal to or greater than the Nth wavelength than when the reflected light has a wavelength less than the Nth wavelength; The printed matter according to claim 3 or 6.

8. The visible light region is included in a wavelength region less than the first wavelength, The printed matter according to claim 7 , wherein the first wavelength to the Nth wavelength are included in the infrared region.

9. A method for determining authenticity of a printed matter according to claim 3 or 6, comprising: Irradiating the printed matter with light; Identifying, as the first portion, a portion in which the reflected light from the printed matter is brighter when the reflected light has a wavelength equal to or greater than the first wavelength than when the reflected light has a wavelength less than the first wavelength; Identifying a portion that is brighter when the reflected light has a wavelength equal to or greater than the wavelength of the (N-1) wavelength as the (N-1) portion, By identifying a portion where the reflected light is brighter when the reflected light has a wavelength equal to or greater than the Nth wavelength than when the reflected light has a wavelength less than the Nth wavelength as the Nth portion, Identifying each of the first through Nth portions; determining the authenticity of the printed matter based on the identification result; Authenticity determination method.

10. Instead of determining the authenticity of the printed matter based on the identification result, each of the identified first to Nth portions is colored with a designated color, and an image in which each of the colored portions is combined is displayed. The authenticity determination method according to claim 9.

11. The authenticity determination device for a printed matter according to claim 3 or 6, A light source that illuminates the printed matter; N filters numbered 1 through N; N imaging units numbered from first to Nth; A specific part; A determination unit, The first filter removes light components less than the first wavelength from the reflected light from the printed matter illuminated by the light source, the (N-1)th filter removes light components less than the (N-1)th wavelength from the reflected light, and the Nth filter removes light components less than the Nth wavelength from the reflected light, The first imaging unit captures an image of the light component that has passed through the first filter to obtain a first reflected image, the (N-1)th imaging unit captures an image of the light component that has passed through the (N-1) filter to obtain an (N-1)th reflected image, and the Nth imaging unit captures an image of the light component that has passed through the Nth filter to obtain an Nth reflected image, the identification unit identifies a portion displayed brighter than other portions in the first reflection image as the first portion, a portion other than the (N-2)th or earlier portion displayed brighter than other portions in the (N-1)th reflection image as the (N-1) portion, and a portion other than the (N-1)th or earlier portion displayed brighter than other portions in the Nth reflection image as the Nth portion; The determination unit determines authenticity of the printed matter based on a result of identification by the identification unit. Authenticity determination device.

12. The authenticity determination device for a printed matter according to claim 3 or 6, N types of light sources, numbered from first to Nth; An imaging unit; A specific part; A determination unit, the first light source illuminates the printed matter with light having a wavelength equal to or greater than the first wavelength; the (N-1)th light source illuminates the printed matter with light having a wavelength equal to or greater than the (N-1)th light source, and the Nth light source illuminates the printed matter with light having a wavelength equal to or greater than the Nth light source, the imaging unit images a first reflected light reflected from the printed matter illuminated by the first light source to obtain a first reflected image, images the (N-1)th reflected light reflected from the printed matter illuminated by the (N-1) light source to obtain an (N-1)th reflected image, and images the Nth reflected light reflected from the printed matter illuminated by the N light source to obtain an Nth reflected image; the identification unit identifies a portion that appears brighter than other portions in the first reflected image as the first portion, a portion other than the (N-2)th or earlier portion that appears brighter than other portions in the (N-1) reflection image as the (N-1) portion, and a portion other than the (N-1) or earlier portion that appears brighter than other portions in the Nth reflection image as the Nth portion; The determination unit determines authenticity of the printed matter based on a result of identification by the identification unit. Authenticity determination device.

13. a coloring unit that colors each of the first to Nth portions in a different color instead of the determination unit, The display control unit further includes a display control unit that displays an image in which the portions colored by the coloring unit are combined. The authenticity determination device according to claim 11.

14. a coloring unit that colors each of the first to Nth portions in a different color instead of the determination unit, The display control unit further includes a display control unit that displays an image in which the portions colored by the coloring unit are combined. The authenticity determination device according to claim 12.

Images