JP2006213017A - Infrared absorption printed matter and its reading method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an infrared absorption printed matter wherein reading of an information pattern by a third person is difficult, reading of the information pattern and at the same time, its truth or falsehood also can be judged, and to provide its reading method. <P>SOLUTION: In the infrared absorption printed matter comprising an infrared absorption layer formed by printing a specific information pattern on one side or both sides of a substrate having an infrared reflection property, and an infrared permeable layer printing formed by using an ink having an infrared permeability thereon, an infrared absorption peak wavelength of an infrared absorber contained in each specific component forming the information pattern of the infrared absorption layer of the printed matter, is constituted to be different. Further, when the information pattern of the printed matter is read, a light having a radiation peak on an almost same wavelength as the infrared absorption peak wavelength of each infrared absorber. Then a component of the information pattern corresponding to each infrared absorber is successively read, and those successively read components are joined by adding those successively read components to be read as one information pattern. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an infrared-absorbing printed material obtained by printing a predetermined information pattern using an ink containing an infrared absorber, and a method for reading the information pattern by irradiating it with predetermined light.

  Conventionally, in order to prevent counterfeiting and maintain confidentiality, a predetermined information pattern is printed and formed on one or both sides of a substrate having reflectivity with respect to infrared rays using ink containing an infrared absorber. Infrared-absorbing prints in which a layer that conceals or camouflages the information pattern is formed using colored (including white) ink that is transparent to infrared rays. According to this, the information pattern printed and formed on the substrate cannot be directly read with the naked eye, and unless the intensity of infrared rays reflected by irradiating light is optically detected by an infrared camera or the like, Since the information cannot be read, the security can be improved as compared with the case where a visible information pattern is formed with normal ink.

  In such infrared absorption printed matter, for example, carbon black can be used as an infrared absorber. Carbon black exhibits a strong absorption characteristic for light in a wide wavelength region, but has a strong absorption at a specific wavelength. It has no concealment and is very bad.

  Therefore, in Patent Document 1, an infrared absorption layer is formed on one surface side of a substrate, and a camouflage pattern layer that is visible with visible light is formed on one or the other surface side of the infrared absorption layer. In a printed matter, the infrared absorption layer is divided into a first region and a second region having different infrared absorption characteristics in a plan view, and the first region and the second region are difficult to visually recognize under visible light. It has been proposed to have a configuration including In this case, when an infrared absorption image is formed by the first region (first printing layer) and the second region (second printing layer) having different infrared absorption characteristics, the print density and the printing accuracy are small. Even if the infrared absorption image pattern can be recognized under visible light due to the difference, it is possible to conceal the infrared absorption image pattern under visible light by forming a camouflage pattern layer in addition to the first printing layer and the second printing layer. (See paragraph number 0012 in the document 1). According to the technique described in Patent Document 1, for example, both the first and second regions appear black under visible light, but when viewed through an infrared camera or the like, one region is black and the other region is white. It is possible to realize a printed matter that looks like this.

JP-A-10-244747 (paragraph numbers 0011 to 0016, paragraph number 0058, etc.)

  As described above, according to the infrared absorption printed matter described in Patent Document 1, the infrared absorption layer is composed of the first region and the second region having different infrared absorption characteristics in plan view, and these Not only is it difficult to distinguish the regions from each other under visible light, that is, it is difficult to visually recognize the region, but also a camouflage pattern layer is formed thereon, so that the region is formed by the first region and the second region. The concealability of visible infrared light image patterns (information patterns) under visible light can be improved.

  However, the difference in the infrared absorption characteristics between the first and second regions in this case is specifically attributed to the presence or absence of the concentration of the infrared absorbing pigment (infrared absorber) or the difference in concentration. However, the infrared image information pattern, which was difficult to visually recognize with visible light, is one type of light that includes infrared light that matches its infrared absorption characteristics. If only the light is irradiated, there is a problem that it can be read relatively easily using an optical device such as an infrared camera.

  Patent Document 1 discloses a method of reading an infrared absorption image pattern by using an infrared camera having a single type of LED having a predetermined peak emission wavelength in the infrared region as a light source and a visible light cut filter in a camera lens. A method for reading the entire infrared absorption image pattern composed of the first region (first printing layer) and the second region (second printing layer) at once is described (paragraph number 0058). In such a method, it cannot be determined whether the read infrared absorption image pattern is genuine (true) or fake (false). That is, if the shape of the infrared absorption image pattern read by the infrared camera based on the intensity of the reflected light when the printed material is irradiated with one type of infrared light is the same, it is a fake infrared absorption image pattern. Even so, as long as it is judged from the overall shape, the obtained infrared absorption image pattern must be judged to be genuine.

  The present invention addresses such problems, and an infrared absorption printed matter obtained by printing a predetermined information pattern using an ink containing an infrared absorber, and a reading method thereof, An object of the present invention is to provide an infrared-absorbing printed material that is relatively difficult to read and that can also determine its authenticity (authenticity) at the same time as reading an information pattern and a reading method thereof.

  In order to achieve the above object, the invention according to claim 1 of the present application prints a predetermined information pattern on one or both sides of a base material having reflectivity with respect to infrared rays using ink containing an infrared absorber. An infrared absorbing layer formed, and an infrared transmitting layer printed on the infrared absorbing layer using an ink having infrared transparency so that the presence of the infrared absorbing layer is difficult to see; In the infrared-absorbing printed material having the above-mentioned, the infrared absorbing material contained in each of the predetermined components forming the information pattern when viewed from the front surface side or the back surface side of the printed material (that is, in plan view) The infrared absorption peak wavelength is different. In other words, in the infrared absorption layer, infrared absorbers having different infrared absorption peak wavelengths are used for each predetermined component forming the information pattern.

  In this case, the infrared absorber contained in the infrared absorption layer preferably has an absorption peak in the near infrared region having a wavelength longer than 750 nm. This is because the wavelength region (invisible region) that is generally invisible to the human eye is from around 750 nm. Therefore, by using an absorber having an absorption peak in the wavelength region of 750 nm or more, the difference in light reflectance can be reduced. This is because it can be made invisible. Further, in order to effectively utilize the width of the near infrared region, that is, the invisible region, the lower end region of the invisible region is included.

  The invention according to claim 3 of the present application is configured as follows as a method for optically reading a predetermined information pattern printed on the printed matter by irradiating the infrared absorbing printed matter according to claim 1 with light. It is a thing.

  That is, the infrared printed matter has a light emission peak at the same number as the number of infrared absorbers assigned to the constituent parts of the information pattern and at substantially the same wavelength as the infrared absorption peak wavelength of each infrared absorber. The component part of the information pattern that is formed by the infrared absorber that absorbs light in the wavelength range and absorbs light in the wavelength region of the irradiated light has a lower infrared reflectance than other components Then, the constituent parts of the information pattern corresponding to the individual infrared absorbers are sequentially read, and these sequentially read constituent parts are added together and read as one information pattern.

  According to this method, an optical device such as an infrared camera is used by sequentially irradiating light having a light emission peak at substantially the same wavelength as the infrared absorption peak wavelength of the infrared absorber assigned to each component of the information pattern. Unless each component of the information pattern is read correctly and sequentially, it cannot be read as a single information pattern, so the optical characteristics of the infrared absorber assigned to each component of the information pattern and how to assign it are known. No third party can easily read the information pattern.

  In the invention according to claim 4 of the present application, one information pattern obtained by adding together the components sequentially read as described above is collated with an information pattern registered in advance, and the two match. It is determined that the information pattern is true only when In this case, the registration of the information pattern and the comparison with the read information pattern are performed using, for example, a memory, a control, which includes an optical device such as a required light source or an infrared camera, or is used in combination with these optical devices. This can be done in an information pattern reading apparatus incorporating a chip for use and control software.

  According to this method, for each predetermined component of the information pattern, the corresponding light is sequentially irradiated to accurately read all the components, and one information pattern obtained as a result of adding them is registered in advance. Since it is not determined to be a true information pattern unless it matches the read information pattern, it is possible to easily determine the authenticity of the read information pattern.

  In the invention according to claim 5 of the present application, an information pattern is formed in a predetermined area, and a portion that is a negative of the information pattern in the area is included in a predetermined component of the information pattern. The term “absorber” refers to a case where the reading method according to claim 3 is applied to reading of an infrared-absorbed print formed with inks containing infrared absorbers having different infrared absorption peak wavelengths. In this case, the component part (positive part) of the information pattern corresponding to each infrared absorber and the negative part are sequentially read, and these sequentially read parts are added together. The information pattern is determined to be true when the resulting area matches the predetermined area, and the information pattern is determined to be false when they do not match.

  According to this method, for each predetermined component (positive part) and negative part of the information pattern, corresponding light is sequentially irradiated to accurately read all the parts, and these are added together. As long as the resulting area does not match the predetermined area, it is not determined to be a true information pattern. For example, a predetermined component part of the information pattern, that is, a positive part, can be formed in the same manner as the real one by unauthorized means. As long as the negative part is not accurately formed using an ink containing an infrared absorber having predetermined optical characteristics, it is not determined to be a genuine information pattern, that is, a fake information pattern. It will be determined that. The authenticity of the read information pattern can be easily determined.

  In the invention according to claim 6 of the present application, in the method for reading an infrared absorbing printed matter as described above, when the component parts sequentially read are added to form one information pattern, there is a duplication of the component parts. It is determined to be a fake information pattern.

  According to this method, for example, in the case where a fake information pattern having a planar shape similar to a real information pattern is formed using infrared absorbing ink that absorbs in a wide range of the infrared region. When the sequentially read constituent parts are added to form one information pattern, the constituent parts are overlapped. Therefore, it can be easily determined that the read information pattern is not genuine, that is, fake. Thus, it is possible to determine the authenticity of the read information pattern more strictly.

  According to the infrared absorption printed matter of the present invention, since the infrared absorber having a different infrared absorption peak wavelength is used for each predetermined component part forming the information pattern of the infrared absorption layer, the third aspect of the present invention is provided. To the information printed on the information pattern unless all the constituent parts of the information pattern are read by an optical device such as an infrared camera by sequentially irradiating light corresponding to each infrared absorber in the manner described in 6 The pattern cannot be recognized correctly. In this way, it is possible to realize an infrared absorbing printed material and a reading method thereof, in which reading of an information pattern by a third party is relatively difficult.

  In particular, according to the inventions according to claims 4 to 6, the coincidence between the information pattern obtained as a result of adding the sequentially read components and the previously registered information pattern, and the information pattern sequentially read The read information pattern is genuine as long as it does not satisfy the predetermined conditions such as the matching of the area combining the component part and the negative part and the predetermined area, and the fact that there is no overlap in the component part of the sequentially read information pattern It is not determined that the information pattern is a fake information pattern. Thus, it is possible to determine not only the reading of the information pattern formed on the infrared absorption printed matter but also the authenticity.

  The method of the present invention can be used as a means for determining the reading and authenticity of a relatively simple information pattern such as a one-dimensional barcode, and also has more information than a one-dimensional barcode. It can also be suitably used for reading and authenticating a relatively complicated information pattern such as a two-dimensional code (for example, a QR code) or a mark that can be used.

  The information pattern to be read by the method of the present invention is recorded using an ink containing an infrared absorber on a substrate having infrared reflectivity, and the infrared absorber used for the ink in this case For example, those having an absorption peak in the wavelength region of 750 nm or more, particularly those having an absorption peak in the near infrared region of the wavelength of 750 to 1300 nm are preferable. Examples of such an infrared absorber (infrared absorbing dye) include naphthalocyanine-based, phthalocyanine-based, cyanine-based, and diimonium-based pigments. Among these, naphthalocyanine-based dyes are preferable because they are effective in terms of light resistance, but are not limited thereto.

  Examples of the ink for forming the infrared transmission layer include process color inks (C, M, Y, and K colors) used in normal offset and silk printing. The ink in this case needs to be made of non-carbon, but is not particularly limited otherwise. The reason for using non-carbon ink is that ink containing carbon black does not have a peak in the near-infrared region and absorbs almost all light.

  As an infrared reflective base material used for the infrared absorption printed matter of the present invention, for example, a white paper, a white film printed on a plastic film, or the like can be given. Examples of the plastic film in this case include polypropylene (PP), polyvinyl chloride (PVC), polyethylene terephthalate (PET), and synthetic paper. Although it is considered that there is an advantage of paper and film depending on the use of the finished product, which is not generally good, in the embodiment of the present invention to be described later, white paper was selected because of its low cost and ease of handling.

Examples of the present invention will be described below.
<Infrared absorbing print α>
As shown in FIG. 1 and FIG. 2, the information pattern P is divided into A and B regions on a base material having infrared reflectivity (manufactured by Hokuetsu Paper Co., Ltd .; N-W 360 g / m ² ) 2, and the absorption regions are different. Offset printing was performed by assigning each of A and B with an infrared absorbing ink (ink containing an infrared absorber). At this time, ink having an absorption peak at 925 nm was assigned to the area A, and ink having an absorption peak at 750 nm was assigned to the area B. Then, the infrared transmission layer 4 was formed by performing arbitrary design printing on the infrared absorption layer 3 composed of the A and B regions with a process color ink having transparency to infrared rays. In the infrared absorbing printed material α thus produced, it was difficult to confirm the information pattern P by visual observation.

  The specific contents of the infrared absorbing ink and the process color ink used for the infrared absorbing printed material α are as follows.

"Infrared absorbing dyes used for infrared absorbing inks assigned to A and B areas"
A area: YKR-5010 (naphthalocyanine dye) manufactured by Yamamoto Kasei Co., Ltd.
B region: Sanyo Dye, NC501 (Naphthalocyanine dye)

“Manufacturing method of each infrared absorbing ink (2 types)”
Infrared absorbing ink was prepared by dispersing 5 parts by weight of an infrared absorbing dye and 95 parts by weight of a UV resin (manufactured by TOKA: UV161 Medium S) for 10 minutes using a bead mill.

Process color ink
Indigo / Red / Yellow: TOKA, Best Cure UV 161 S Series Black: TOKA, Best Cure UV NVR Series

《Infrared absorbing printed matter β》
As shown in FIG. 3 and FIG. 4, an information pattern P is divided into A, B, and C regions on a base material having infrared reflectivity (made by Hokuetsu Paper Industries Co., Ltd .; N-W 360 g / m ² ) 2 to absorb regions. A, B, and C were assigned with different infrared absorbing inks, and offset printing was performed. At this time, an ink having an absorption peak at 1070 nm was assigned to the area A, an ink having an absorption peak at 870 nm (cyanine type) was assigned to the area B, and an ink having an absorption peak at 750 nm was assigned to the area C. . The infrared transmission layer 4 was formed by applying arbitrary design printing with process color ink having transparency to infrared rays from above the infrared absorption layer 3 composed of these A, B, and C regions. As a result, it was possible to make the information pattern P difficult to see. In the infrared absorbing printed material β thus produced, it was difficult to visually confirm the information pattern P.

  In addition, the infrared absorption pigment | dye in the infrared absorption ink used for the infrared absorption printed matter (beta) is as follows. In addition, the production method of each infrared absorbing ink and the specific contents of the process color ink are the same as in the case of the infrared absorbing printed matter α described above.

“Infrared absorbing dyes used in infrared absorbing inks assigned to A, B, C regions”
A region: Nippon Carlit Co., Ltd., CIR-1085 (diimonium dye)
B region: manufactured by Sumitomo Seika Co., Ltd., SD50-E04N (cyanine dye)
C region: Sanyo Dye Company, NC501 (Naphthalocyanine dye)

<Reading information pattern>
The above infrared absorption printed matter β was used as a reading object, and reading of the information pattern was attempted. As shown in FIG. 5, the information pattern reading apparatus used in this case is a CCD camera (manufactured by KEYENCE; CV-020) 10 and an infrared transmission filter (manufactured by Asahi Spectroscopic Co., Ltd.) attached to the front surface of the camera lens. LI0750, the spectral characteristics of which are shown in FIG. 6), and bandpass filters (manufactured by IR SYSTEME; center wavelength 750; (870, 910, 1069 nm) 15, 16, 17, a data processing device 20 including a personal computer (PC) to which an image signal from the CCD camera 10 is input, and output from the data processing device 20 The image data and judgment data are displayed on the screen based on the The monitor has a monitor (display means) 21 for displaying.

  Here, the data processing device 20 includes a calculation unit 20a in which a regular information pattern printed and formed on the infrared absorption print β is registered in advance, and a determination process as described later based on the output from the calculation unit 20a. And a determination unit 20b for performing the determination, and an output unit 20c for outputting a determination result by the determination unit to the monitor 16 or the like.

  Using the information pattern reading apparatus having such a configuration, each of the LEDs 12, 13, and 14 is sequentially pulsed with the infrared absorption printed material β as a reading object, and an image from the CCD camera 10 is read in synchronization with the LED. It was. As a result, at the time of light irradiation from the LEDs 12, 13, and 14 having the center wavelengths of 750 nm, 870 nm, and 1070 nm, the pattern of the infrared absorbing ink having the corresponding absorption peak, that is, the patterns of the regions C, B, and A, The images could be read sequentially with sufficient contrast in this order.

《Authenticity judgment of information pattern》
(Judgment example 1)
Using the above infrared absorbing printed matter β and the read image, the authenticity determination of the information pattern (information pattern P consisting of regions A, B, and C shown in FIGS. 3 and 4) formed thereon is performed as follows. It was done like that.

  A regular information pattern printed and formed on the infrared absorbing printed material β is registered in advance in the calculation unit 20a of the data processing device 20. Then, the images (parts of the information pattern, that is, the patterns of regions C, B, and A) read at the time of irradiation from the LEDs 12, 13, and 14 having the center wavelengths of 750 nm, 870 nm, and 1070 nm are superimposed. Here, if there is no overlapping part in all the images to be superimposed, the determination part 20b identifies the printed matter as normal on the image calculation part, and conversely, if there is an overlapping part, it is identified as a fake. In the previous infrared-absorbed printed material β, there was no overlapping portion, and it was identified as normal.

(Judgment example 2)
The same pattern as the information pattern registered in advance in the computing unit 20a is printed in black and white with a copier, and the light emitted from each LED as a light source is sequentially irradiated in the same manner as in the above embodiment, As a result, the entire area of the information pattern was read with all the irradiation light, and the overlapping process was performed on the calculation unit 20a. As a result, all the read images were duplicated and identified as fake by the determination unit 20b.

(Judgment example 3)
An information pattern was formed with an ink having an absorption peak at 870 nm, and printing was performed with an ink having an absorption peak at 1070 nm on a negative pattern portion that was not an information pattern to obtain an infrared absorption printed material γ. On the other hand, an information pattern formed of ink having an absorption peak at 870 nm of the infrared absorbing printed material γ is registered in advance in the arithmetic unit 20a of the data processing device 20 as a normal pattern. In this case, on the calculation unit 20a, it is assumed that the regular information pattern exists in the determined area, and the area has a size obtained by adding the information pattern and the negative pattern. In addition, for example, an image obtained by irradiating light having a wavelength of 750 nm and a light having a wavelength of 870 nm is recognized as an information pattern, and an image obtained by light having a wavelength of 910 nm and light having a wavelength of 1070 nm is recognized as a negative pattern.

  After doing so, the infrared absorption printed matter γ was sequentially irradiated with light having emission center wavelengths of 750 nm, 870 nm, 910 nm, and 1070 nm to read images. As a result, an information pattern and its negative pattern were obtained when 870 nm and 1070 nm light was irradiated. The images read in this way are added, and if the result is equal to the sum of the positive and negative patterns of the registered information pattern, it is identified as a regular (genuine) printed matter, otherwise it is identified as a fake. Identify. As a result, the infrared absorbing printed material γ was identified as a regular printed material.

The top view which shows typically an example of the infrared absorption printed matter produced in the Example of this invention. The longitudinal cross-sectional view which cut | disconnects by the II-II line | wire of FIG. 1, and shows the layer structure of an infrared rays absorption printed matter typically. The top view which shows typically the other example of the infrared absorption printed matter produced in the Example of this invention. FIG. 4 is a longitudinal sectional view schematically showing a layer configuration of an infrared-absorbing printed material by cutting along the line IV-IV in FIG. 3. The block diagram which shows schematically the structure of use with the information pattern reading apparatus used in the Example of this invention. The figure which shows the spectral characteristics of the infrared transmission filter (Asahi Spectrometer Co., Ltd .; LI0750) with which the CCD camera was mounted | worn in the information pattern reader used in the Example of this invention.

Explanation of symbols

2 Substrate 3 Infrared absorbing layer 4 Infrared transmitting layer A, B Information pattern component (region constituting information pattern)
α, β Infrared Absorbed Print P Information Pattern

Claims (6)

An infrared absorbing layer formed by printing a predetermined information pattern on one or both sides of a base material having reflectivity to infrared using an ink containing an infrared absorber, and presence of the infrared absorbing layer Infrared absorbing printed matter having an infrared transmitting layer printed and formed using an ink having infrared transparency on the infrared absorbing layer so as to be difficult to see,
The infrared absorption peak wavelength of the included infrared absorber is different for each predetermined component forming the information pattern of the infrared absorption layer as viewed from the front side or the back side of the printed material. Infrared absorption printed matter characterized by the above.   2. The infrared absorbing printed matter according to claim 1, wherein each of the infrared absorbers contained in the infrared absorbing layer has an absorption peak in a near infrared region having a wavelength longer than 750 nm. A method of optically reading a predetermined information pattern printed on the printed matter by irradiating the infrared absorbing printed matter according to claim 1 with light.
Light having the same number as the number of infrared absorbers assigned to the constituent parts of the information pattern on the infrared printed matter and having a light emission peak at substantially the same wavelength as the infrared absorption peak wavelength of each infrared absorber. Are irradiated sequentially,
The component part of the information pattern formed by the infrared absorber having absorption in the wavelength range of the irradiated light makes use of the fact that the infrared reflectance is lower than that of the other component parts. Read the constituent parts of the information pattern corresponding to the absorber sequentially,
An infrared absorbing printed matter reading method, wherein the sequentially read components are added together and read as a single information pattern.   One information pattern read by adding together the sequentially read component parts is checked against a previously registered information pattern, and the read information pattern is determined to be true only when the two match. The method for reading an infrared absorption printed matter according to claim 3. As an infrared absorption printed matter, an information pattern is formed in a predetermined area, and a portion that is a negative of the information pattern in the area is an infrared absorber included in the predetermined component of the information pattern Uses infrared-absorbed prints formed with inks containing infrared absorbers with different infrared absorption peak wavelengths,
Read the information pattern component part corresponding to each infrared absorber and the negative part sequentially, and add these sequentially read parts together.
The infrared absorption printed matter reading according to claim 3, wherein the information pattern is determined to be true when the area obtained as a result of the addition matches the predetermined area, and the information pattern is determined to be false when the area does not match. Method.   6. The infrared absorption according to claim 3, wherein when the component parts sequentially read are added to form one information pattern, if there is an overlap of the component parts, it is determined as a false information pattern. How to read printed matter.

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