JP2007136983A - Anti-counterfeit printed matter, and discrimination method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide anti-counterfeit printed matter in which an image for verification, formed of infrared-absorbing printing ink, is concealed in a visually unrecognizable state, and a discrimination method for the anti-counterfeit printed matter, which enables the printed image for verification, concealed in the printed matter like this, to be read by an infrared information reading device such as an infrared camera and surely verified. <P>SOLUTION: The printed image for verification is provided on an infrared reflexible substrate by using each of at least three kinds of infrared-absorption printing inks different in absorption peak in an infrared area, and a printed layer for concealment is also provided in such a manner as to cover the printed image for verification. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an anti-counterfeit printed matter in which a verification image formed by infrared absorbing printing ink is concealed in an invisible state, and a verification printed image concealed in such a printed matter. The present invention relates to a method for discriminating a false image prevention printed matter that can be read and reliably verified by an infrared information reading device such as an infrared camera.

Conventionally, securities such as stock certificates, bonds, checks, gift certificates, lotteries, and commuter passes are often provided with machine-readable code marks such as barcodes and OCR characters. Such machine-readable information is formed on, for example, a base material surface that reflects infrared light in the near infrared region, using ink that absorbs infrared light in the near infrared region (see, for example, Patent Document 1). .)
Further, by utilizing the infrared reflectivity of white ink and the infrared absorptivity of black ink, information that can be read by a machine may be printed on the securities as a bar code pattern code mark. Securities having such a code mark read the code mark by irradiating the code mark portion with infrared rays and measuring the reflection intensity of the infrared rays reflected from the portion. In such a case, in general, in order to prevent unauthorized reading of recorded information, the visible light is blocked and the information is covered with a concealing layer that transmits infrared light. This prevents information from being easily read visually.

  However, since the infrared absorbing material such as carbon black has a light absorbing property even in the visible region, even if a concealing layer is formed, its concealing power is insufficient. In addition to being mechanically read by an infrared information reader, its presence is easily readable by the naked eye, and it is still insufficient as a means for effectively preventing forgery and alteration using copying and the like.

  In order to prevent the predetermined concealment information from being read with the naked eye, conventionally, information has been recorded with a material that has low light absorption in the visible region and exhibits predetermined optical absorption characteristics in regions other than the visible region. For example, there is a method in which a heat ray absorbing glass or an infrared absorbing glass is pulverized and an infrared absorbing material formed by pigmenting it is contained in the ink, and a code mark is formed with the ink. Since the ink containing this infrared absorbing material has little light absorption in the visible region, it is difficult to visually confirm the information formed, so it is considered as an effective means for counterfeiting, alteration, tampering, etc. I came.

  However, printed matter in which information is formed with the above-described ink and infrared information is absorbed by the information portion has an advantage that it can be easily detected using various infrared rays in a wide infrared region. It had the disadvantage that the benefits were reversed and it was easy to read. That is, it can be easily read by an infrared information reading device such as an infrared camera, and concealment information such as a code mark is determined. For this reason, forgery is performed based on information read by an infrared camera, and tampering may be performed by joining or pasting light-absorbing parts based on the reading result. There is a problem.

The above problems can be solved by printing code marks etc. using two types of infrared absorbing printing inks having different spectral absorption characteristics. In this case, infrared absorbing properties can be achieved by using two types of light sources or filters. An image printed with printing ink is captured on a single black-and-white screen, and authenticity is determined by reading each of the images. Similarly, by providing an image with two or more types of infrared absorbing printing inks having different spectral absorption characteristics, it is possible to further improve the anti-counterfeit effect. In this case, too, each of the images captured in one screen is displayed. It must be read and true / false judgments made, making true / false judgments very difficult.
JP 2000-309736 A

  The present invention has been made paying attention to the above problems, and a forgery-preventing printed matter in which at least a verification image is provided with three or more types of infrared-absorbing printing inks having different absorption peaks, The reflection image information of each verification print image in such a printed matter is individually captured under infrared irradiation, color information is added to the obtained reflection image information, and then they are combined into a color image. It is an object of the present invention to provide a method for discriminating forgery-preventing printed matter, characterized in that the presence and contents of a print image concealed in a forgery-preventing printed matter can be verified based on a color image.

In order to achieve the above-mentioned object, the invention according to claim 1 is a printing for verification by each of at least three types of infrared-absorbing printing inks having different absorption peaks in the infrared region on an infrared-reflective substrate. An anti-counterfeit printed matter in which an image is provided and a concealing print layer is further provided so as to cover the verification print image.

  The invention according to claim 2 is the anti-counterfeit printed matter according to claim 1, wherein the three kinds of infrared absorbing printing inks have different absorption peaks in the infrared region, and the absorption there is other infrared absorbing properties. It is characterized by not being interfered by absorption of printing ink.

  Furthermore, in the invention described in claim 3, the reflection state of the infrared rays irradiated on the printing surface of the anti-counterfeit printed matter described in claim 1 or 2 is expressed as the absorption peak wavelength of the infrared-absorbing printing ink constituting each verification print image. Each image is read by an infrared information reader through a band-pass filter that transmits infrared rays of the same wavelength, and then color information is added to each reflected image information obtained by reading, and then they are combined into a color image. Is a method for discriminating forgery-preventing printed matter, characterized in that the existence and contents of a print image concealed under the concealment print layer can be verified.

  Furthermore, the invention according to claim 4 irradiates the printed surface of the anti-counterfeit printed matter according to claim 1 or 2 with infrared rays having the same wavelength as the absorption peak wavelength of the infrared-absorbing printing ink constituting each verification print image. After that, a step of reading the reflection state by the infrared information reader is performed on each verification print image, and color information is added to each reflection image information obtained by the reading and then they are combined. The present invention is a method for discriminating forgery-preventing printed matter, characterized in that it is possible to verify the presence and contents of a print image concealed under a concealment print layer based on a color image.

The anti-counterfeit printed matter of the present invention is provided with verification print images such as characters and barcodes using at least three types of infrared-absorbing printing inks having different absorption peaks in the infrared region, and further covering them. Since the concealing printing layer is provided, the verification information printed with the infrared absorbing printing ink cannot be visually observed. Such a forgery prevention printed matter can display the reflected image information corresponding to the verification image concealed in the discrimination method of the present invention as a single color image. The existence and contents of the verification print image can be verified easily and accurately, and can be effectively used for authenticity determination.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is an explanatory diagram showing a planar state of a forgery-preventing printed matter of the present invention, and FIG. 2 is an explanatory diagram showing a schematic cross-sectional configuration of the forgery-preventing printed matter 1 of FIG.

  The anti-counterfeit printed matter 1 shown in FIG. 1 is disposed on the outermost surface in a state in which a surface pattern image 11 that is a concealment printing layer and a character image 13 printed with carbon black ink are visible. As shown in FIG. 2, on the infrared reflective substrate 12, a verification print image 14 printed with an infrared absorbing printing ink and a verification image printed with another infrared absorbing printing ink. A print image 15 and a verification print image 16 formed by printing with another infrared absorbing printing ink are formed, and the above-described concealment image is covered so as to cover each of the verification images 14, 15, 16. The printing layer is provided on the upper layer.

  Each of the verification print images 14, 15, 16 is printed with infrared absorbing printing inks having different spectral characteristics in the infrared region. More specifically, each of the verification print images 14, with three types of infrared-absorbing printing inks that have different absorption peaks in the infrared region and whose absorption is not interfered by the absorption of other infrared-absorbing printing inks, 15 and 16 are formed. Therefore, in the forgery prevention printed matter having such a configuration, only the concealed print layer on the outermost surface can be visually observed.

  FIG. 5 shows an example of how reflected image information corresponding to a verification print image is extracted when the anti-counterfeit printed matter 1 of the present invention having such a configuration is determined by the determination method of the present invention. .

  As can be seen from the figure, in extracting the reflected image information, first, the infrared reflection state irradiated to the printing surface of the anti-counterfeit printed matter 1 is changed to the absorption peak wavelength of each infrared absorptive printing ink constituting each verification print image. The information is read by an infrared information reading device through each of band-pass filters 51, 52, and 53 that transmit infrared rays having the same wavelength.

  Specifically, the anti-counterfeit printed matter 1 is irradiated with infrared rays from the infrared irradiation light source 31, and the reflected light is first led to the 30R / 70T beam splitter 54 that reflects 30% of the infrared rays and transmits 70%. The reflected infrared light is guided to the infrared camera 41 side, and the transmitted infrared light is guided to the beam splitter 55 side. Next, the infrared rays that have passed through the beam splitter 54 are led to the 50R / 50T beam splitter 55 that reflects 50% of the infrared rays and pass through 50%, and the infrared rays that have passed therethrough are reflected toward the infrared information reader 43 side. The infrared rays are divided into three so as to be guided to the infrared information reader 42 side. Then, the infrared information reading device 41, through the band-pass filters 51, 52, 53 that transmit the infrared rays having the absorption peak wavelengths of the respective infrared-absorbing printing inks constituting the respective verification print images to the divided infrared rays. 42 and 43, and the reflected image information is extracted.

  FIG. 7 shows a situation when the reflected image information extracted in this way is displayed on the monitors of the infrared information reading devices 41, 42, and 43.

On the other hand, FIG. 4 shows an example in which the reflection image information of the anti-counterfeit printed matter 1 of the present invention is extracted by a method other than the information extraction method described above. In the method shown here, in extracting the reflected image information, first, infrared light having the same wavelength as the absorption peak wavelength of the infrared-absorbing printing ink constituting each verification print image is applied to the printing surface of the anti-counterfeit printed matter 1 for a predetermined amount. The process of irradiating from the light source, reading the reflected state by the infrared information reader and extracting the reflected image information is performed on each verification print image, and the reflected image information is extracted.

  More specifically, first, an infrared ray having the same wavelength as the absorption peak wavelength of the infrared-absorbing printing ink constituting the verification print image 14 is irradiated from the light source 35 to the anti-counterfeit printed matter 1, and then the reflection state is visible light. The reflected image information is extracted by reading by the infrared information reading device 33 through the area cut filter 32. Subsequently, an infrared ray having the same wavelength as the absorption peak wavelength of the infrared-absorbing printing ink constituting the verification print image 15 is irradiated from the light source 36, and then the reflected state is read through the visible light region cut filter 32. The image is read by the device 33 and the reflection image information is extracted. Finally, an infrared ray having the same wavelength as the absorption peak wavelength of the infrared-absorbing printing ink constituting the verification print image 16 is irradiated from the light source 37, and then the reflected state is infrared information via the visible light region cut filter 32. The image is read by the reading device 33 and the reflected image information is extracted.

  FIG. 7 shows a situation when the reflected image information extracted in this way is displayed on the monitors of the infrared information reading devices 41, 42, and 43.

  With the above method, similar to the method shown in FIG. 3, an image based on the reflected image information of the verification print image made of each infrared absorbing printing ink can be viewed. Incidentally, the portion of the character image 13 printed with carbon black ink that absorbs at any wavelength in the infrared region can be seen on any of the monitor screens 4, 5, and 6 shown in FIG.

  When the reflection image information of the verification print image concealed in the anti-counterfeit printed matter 1 is extracted as described above, color information is added to the reflection image information and then combined to obtain a color image. The presence and content of the print image concealed under the concealment print layer is verified based on the above, and the printed matter is discriminated.

  FIG. 6 shows how color information is added to each extracted reflected image information and how a color image is synthesized. A color reduction method is used to synthesize a color image in the same manner as when printing ink is multiplied. By looking at the monitor screen 7 on which a color image that has been visualized in this way and is colored and synthesized is displayed, each verification print image made of three types of infrared-absorbing printing inks can be distinguished and synthesized. It is possible to determine the authenticity of the printed matter only by looking at the color image.

  FIG. 7 is a graph showing an example of the relationship between reflectance and wavelength in each infrared-absorbing printing ink. The reflectance of each ink is measured when a printing layer made of an infrared absorbing printing ink formed on an infrared reflective substrate is measured. As shown in FIG. 7, each infrared absorbing printing ink has absorption peaks 84, 85, 86 that do not overlap with the absorption peaks of other infrared absorbing inks, so that they do not interfere with each other. ing. Therefore, if each verification print image is formed using the infrared absorbing printing ink having such characteristics, the intended determination can be easily and accurately performed with a clear color image.

  The present invention will be described in more detail with reference to specific examples.

White coated paper was used as the infrared reflective substrate. A pattern was printed on the infrared reflective substrate by using an infrared absorbing printing ink 1 (UV curable offset ink) having the following composition by an offset printing method. Moreover, another pattern was printed using the infrared absorptive printing ink 2 of the following composition, and also another pattern was printed using the infrared absorptive printing ink 3 of the following composition. And the pattern for concealment was printed on the upper layer using the process ink of the following composition so that these each pattern might be covered, and the forgery prevention printed matter which concerns on this invention was produced.

[Composition of infrared absorbing printing ink 1]
Infrared absorber YKR-1030 (manufactured by Yamamoto Kasei Co., Ltd.) 5 parts FDS medium TP (manufactured by Toyo Ink Co., Ltd.) 95 parts [Composition of infrared absorbing printing ink 2]
Infrared absorber YKR-3070 (manufactured by Yamamoto Kasei Co., Ltd.) 5 parts FDS medium TP (manufactured by Toyo Ink Co., Ltd.) 95 parts [Composition of infrared absorbing printing ink 3]
Infrared absorber YKR-3081 (manufactured by Yamamoto Kasei Co., Ltd.) 5 parts FDS medium TP (manufactured by Toyo Ink Co., Ltd.) 95 parts [process ink]
FD OL Yellow TC B (Toyo Ink Manufacturing Co., Ltd.)
FD OL Crimson TC (made by Toyo Ink Co., Ltd.)
FD OL Ai TC B (Toyo Ink Manufacturing Co., Ltd.)
Next, irradiate the anti-counterfeit printed matter with light from an incandescent lamp, the reflected light is reflected by 30% of near-infrared light, and is split into two by a beam splitter that transmits 70%, and the transmitted light is reflected by 50% of near-infrared light. Then, the reflected light was divided into three by dividing into two by a beam splitter that transmits 50%. Then, image information was extracted by three CCD cameras through narrowband interference filters (bandpass filters) in which the reflected light divided by each of them was transmitted at the absorption peak wavelength of each infrared absorbing printing ink. A CCD camera without an infrared cut filter was used. Red, yellow, and blue color information was added to each of the three reflected image information extracted in this manner, and a color image was synthesized based on the color subtraction method and displayed on the monitor screen.

  When looking at the anti-counterfeit printed matter, only the surface pattern was visible, but according to the above discrimination method, another color image is synthesized and displayed based on the extracted reflected image information, so a complicated verification print image is displayed. Even if the printed material has a mark, it was possible to accurately determine the authenticity.

  A low-pass filter that sequentially irradiates LEDs having an emission center at the absorption peak wavelength of the infrared-absorbing printing ink constituting the verification print image on the anti-counterfeit printed matter of Example 1 and cuts the reflected light to 700 nm or less. The image was taken with the CCD camera. Red, yellow, and blue color information is added to each reflected image information obtained by such shooting, color reproduction based on a color subtraction method is performed, and the resultant image is combined into a single color image. Was displayed.

  When looking at the anti-counterfeit printed matter, only the surface pattern was visible, but according to the above discrimination method, another color image is synthesized based on the extracted reflected image information and displayed, so a complicated verification print image Even if the printed material has a mark, it was possible to accurately determine the authenticity.

It is explanatory drawing which shows the planar state of the forgery prevention printed matter of this invention. It is explanatory drawing which shows the general | schematic cross-section structure of the forgery prevention printed matter shown in FIG. It is explanatory drawing which shows a mode when the reflective image information corresponding to the printing image for verification in the forgery prevention printed matter shown in FIG. 1 is extracted. It is explanatory drawing which shows the other mode when the reflective image information corresponding to the verification print image in the forgery prevention printed matter shown in FIG. 1 is extracted. It is explanatory drawing which shows a mode when the image | video based on each reflection image information obtained from the forgery prevention printed matter is displayed on a monitor screen. It is explanatory drawing which shows the mode of addition of color information to each extracted reflected image information, and the mode of a color image composition. It is a graph which shows the relationship between the reflectance in each infrared rays absorptive printing ink, and a wavelength.

Explanation of symbols

1 ·· Anti-counterfeit printed matter 4, 5, 6 · · Monitor screen 7 on which a verification print image is projected · · Monitor screen 8 on which a color image is projected · · A graph showing the spectral characteristics of each infrared absorbing printing ink 11. Surface pattern image 12. Infrared reflective base material 13. Character image 14, 15, 16 printed with carbon black ink. Verification image 32. Visible light cut filter 33, 41. 42, 43 ... Camera 34 ... Monitor 35, 36, 37 ... Light source 51, 52, 53 ... Band pass filter 54 ... 30R / 70T beam splitter 55 ... 50R / 50T beam splitter 84, 85, 86 ...・ Absorption peak of infrared absorbing printing ink

Claims (4)

  On the infrared reflective substrate, a verification print image is provided by each of at least three types of infrared absorptive printing inks having different absorption peaks in the infrared region, and the verification print image is covered. An anti-counterfeit printed matter, further comprising a concealing printing layer.   2. The three types of infrared absorbing printing inks according to claim 1, wherein absorption peaks in the infrared region are different from each other, and absorption therein is not interfered by absorption of other infrared absorbing printing inks. Anti-counterfeit printed matter.   A bandpass filter that transmits infrared rays having the same wavelength as the absorption peak wavelength of the infrared-absorbing printing ink constituting each verification print image, with respect to the reflection state of the infrared rays irradiated on the printing surface of the anti-counterfeit printed matter according to claim 1 or 2. The color information is added to each reflection image information obtained by the reading through the infrared information reading device, and then combined to form a color image. Based on this, the image is concealed under the concealment printing layer. A method for discriminating forgery-preventing printed matter, characterized in that the presence and content of a printed image can be verified.   An infrared ray having the same wavelength as the absorption peak wavelength of the infrared-absorbing printing ink constituting each verification print image is irradiated on the printing surface of the anti-counterfeit printed matter according to claim 1 or 2, and thereafter the reflection state is read as infrared information. The process of reading by the device is performed on each verification print image, and color information is added to each reflection image information obtained by the reading, and then they are combined into a color image. A method for discriminating forgery-preventing printed matter, characterized in that the presence and contents of a print image concealed under a layer can be verified.