JP2014172309A - Identification medium and identification method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a mechanically readable identification medium with high difficulty in forgery; and an identification method thereof.SOLUTION: An identification medium with extremely high difficulty in forgery includes a non-metal optical layer 12 having a characteristic absorption different from the others in at least a part of the near infrared wavelength range. The identification medium achieves a highly accurate authenticity determination through mechanical reading by optical sensors 34-37 and an eddy current sensor so as to enhance forgery resistance. An identification method of the identification medium is also provided.

Description

  The present invention relates to an identification medium and a method for identifying the same that perform authenticity determination by machine reading by a sensor.

  In general, as identification media, seals and tags for products are known in addition to securities such as banknotes, stock certificates, gift certificates, and credit cards. Although such identification media have been subjected to printing by elaborate printing technology to prevent unauthorized use due to counterfeiting / duplication, these elaborate printing, etc. in view of the frequent occurrence of fraudulent use due to forgery / duplication in recent years In addition, anti-counterfeiting measures using special inks are being implemented.

  For example, fluorescent copies that emit light in the visible light range when irradiated with ultraviolet light, OVD (Optically Variable Device) ink that changes in color and brightness depending on the viewing angle, etc. are printed on paper, making copies such as color copies. There are methods that cannot be easily counterfeited by machine.

  However, as for the recent counterfeit products, elaborate counterfeit products in which a product imitating the above-described fluorescent ink or OVD is added in addition to the color copy. These counterfeit products can be easily discriminated if compared with genuine products and viewed by experts, but it is difficult for ordinary people to easily determine authenticity.

  Therefore, there are many securities that use anti-counterfeiting measures that perform true / false judgments by machine reading by sensors in addition to visual true / false judgments. This is also effective for a bill discriminator for a vending machine, for example, in which authenticity cannot be determined visually.

  As a measure for preventing counterfeiting by machine reading, a method of mixing a material that reacts with a sensor that cannot detect the functionality visually but can detect the functionality into ink. For example, magnetic ink in which magnetic powder is mixed in the ink is visually visible as black ink, but an MR (Magneto Resistive) sensor can detect the presence or absence of magnetism.

  In addition, paying attention to infrared rays, particularly near infrared rays, there is a forgery prevention measure using ink that absorbs or transmits part of the near infrared region. For example, a method that combines black ink, which is mainly composed of carbon black, which is a process ink, and black ink that does not absorb in the near-infrared region, and that there is almost no specific absorption in the visible light region and part of the near-infrared region. Examples thereof include a method using an ink having absorption, and a method by mixing an ink having absorption in a part of the near-infrared region into another process ink (other than black).

  The method of performing machine reading by these sensors has a problem that costs for introducing the equipment are incurred. Further, in the case of performing authenticity determination with an inexpensive sensor or a small number of reading points, there is a possibility that even a counterfeit product may be determined as a genuine product.

  However, when only the feature points in the near-infrared region are detected by the sensor and the authenticity determination is performed, there is a problem that it cannot be distinguished from a counterfeit product imitating only the feature points. As a countermeasure against counterfeiting, it is possible to take a countermeasure against simple counterfeiting by detecting a plurality of feature points and performing the authenticity determination. Ink with characteristics in the near-infrared region can also be mixed with multiple types of optical functional materials, resulting in a complex spectral waveform. It becomes an easy identification medium.

  However, such anti-counterfeiting measures are effective when performed in addition to visual authenticity determination, but when performing anti-counterfeiting only by machine reading without performing visual authenticity determination, the spectrum of anti-counterfeit ink is used. Even if the waveform is complicated, there is a risk of being imitated. For example, if the light is controlled with an optical multilayer film using metal, a similar spectral waveform can be created if the medium manufacturing cost and appearance are repeated. In this case, if it can be visually confirmed, it can be recognized as a counterfeit product at a glance, but it is not suitable for an article for identifying authenticity determination only by machine reading.

JP 2005-74641 A JP-A-7-37027 Japanese Patent No. 3246017 JP 2009-149068 A

  The present invention has been made in view of the above circumstances, and performs true / false determination by reading a plurality of reflectances of feature points of a security part having a characteristic spectral waveform by an optical sensor, and further on the medium. It is an object of the present invention to provide an identification medium and a method for identifying the same that can detect the presence or absence of metal by moving the eddy current sensor, thereby providing a high anti-counterfeit effect and further improving the accuracy of identification for authenticity determination. To do.

  In the invention according to claim 1, a nonmetallic optical layer having a characteristic absorption different from the others in at least a part of the near infrared wavelength region is provided on a part of at least one surface of the nonconductive substrate. Features an identification medium.

  The invention according to claim 2 is characterized in that, in the identification medium according to claim 1, a metal pattern layer is embedded in a non-metallic optical layer on a non-conductive substrate.

  The invention according to claim 3 is an identification method for identifying the identification medium according to claim 1 or 2, wherein the non-metallic optical layer is measured by measuring the reflectance of the non-metallic optical layer with respect to a plurality of feature point wavelengths. And an identification method in which the non-metallic optical layer is detected by measuring eddy currents in each part on the non-conductive substrate including the non-metallic optical layer to detect authenticity. To do.

  The invention according to claim 4 is the identification method for identifying the identification medium according to claim 2, wherein the non-metallic optical layer is detected by measuring the reflectance of the non-metallic optical layer with respect to a plurality of feature point wavelengths. And measuring the eddy current of each part on the non-conductive substrate including the non-metallic optical layer, and detecting the presence or absence of the metal pattern layer in the non-metallic optical layer based on the current difference. It is characterized by an identification method in which a determination is made.

  According to the present invention, when the reflectance of the feature point wavelength of the identification medium is scan-measured, the reflectance changes depending on the moving direction. By performing authenticity determination, it is possible to provide an identification medium and a method for identifying the same capable of more accurate authenticity determination.

It is a top view which shows the identification medium which concerns on one embodiment of this invention. FIG. 2 is a cross-sectional view showing the identification medium of FIG. 1 along the line XX ′. It is a characteristic view which showed the spectral characteristic of the security ink used for FIG. It is the schematic which showed the principal part of the optical reading sensor used for the identification method which concerns on one embodiment of this invention. It is the characteristic view which showed the relationship between the security ink to which this invention is applied, and the wavelength of an optical reading sensor. It is the conceptual diagram which showed the relationship between the identification medium of FIG. 1, and an optical reading sensor output. It is the conceptual diagram which showed the relationship between the identification medium of FIG. 1, and an eddy current sensor output. It is the conceptual diagram which showed the output of the eddy current sensor of the identification medium provided with the optical multilayer film. It is sectional drawing which carried out the cross section and showed the identification medium which concerns on other embodiment of this invention. It is the conceptual diagram which showed the relationship between the identification medium of FIG. 9, and an eddy current sensor output.

  Hereinafter, an identification medium and an identification method according to an embodiment of the invention will be described in detail with reference to the drawings.

  FIG. 1 shows an identification medium 1 according to an embodiment, in which a non-metallic optical layer 12 is provided on a part of one surface of a non-conductive substrate 11 (see FIG. 2). The non-metallic optical layer 12 has optical characteristics having characteristic absorption different from others in at least a part of the near-infrared wavelength range, for example, a range of 700 nm to 1000 nm.

  The non-conductive substrate 11 is not particularly specified as long as it can hold the non-metallic optical layer 12 provided on the upper layer. Examples of the non-conductive substrate 11 include paper, plastic, and cloth that are usually used as an identification medium. Moreover, an adhesive or an adhesive may be provided on the lower layer of the non-conductive substrate 11 to form a sticker or a transfer foil. As a printing method in which the nonmetallic optical layer 12 is provided on the substrate 11, an offset printing method, a relief printing method, a gravure printing method, a screen printing method, a flexographic printing method, a pad printing method, and the like are possible.

  The non-metallic optical layer 12 is set to have the spectral characteristics shown in FIG. 3, for example, and absorbs almost all over the visible light region and is visually recognized as black. The color in the visible light region is not limited to black, and any color may be used as long as no metal is used.

  Here, in the present invention, the visible light region is defined as 400 nm to 700 nm. The non-metallic optical layer 12 is at least partially absorbed in the near-infrared wavelength region, and the absorption range may be wide, but the narrower one has a higher anti-counterfeit effect and corresponds to various combinations. Is possible.

  Here, the identification medium 1 is identified by using, for example, four S1 sensors 34, S2 sensors 35, S3 sensors 36, and S4 sensors 37 shown in FIG. Irradiation is performed to read the reflectance of the non-metallic optical layer 12, and the change in wavelength is detected based on the difference in reflectance between adjacent sensors. This difference in reflectance is determined by providing sensors 34 to 37 at a wavelength of 5% or more, preferably 20% or more of the wavelength in FIG. 5, for example.

  The S1 sensor 34, the S2 sensor 35, the S3 sensor 36, and the S4 sensor 37 are combined and arranged in a ring shape as shown in FIG. 4, for example, to form the reading sensor 3, and have a wavelength in the visible light region and the near infrared wavelength region. A corresponding light source is formed. The S1 sensor 34, S2 sensor 35, S3 sensor 36, and S4 sensor 37 irradiate the identification medium 1 with light having desired wavelengths 24, 25, 26, and 27, respectively.

  The S1 sensor 34, the S2 sensor 35, the S3 sensor 36, and the S4 sensor 37 are, for example, arranged with the light receiving element 31 surrounded by the light shielding plate 32 at the center position, and the light irradiated on the light receiving element 31 is not directly incident. It is configured as follows. The light receiving element 31 is not limited to the arrangement shown in FIG. 4 as long as it can receive the reflected light of the sensors 34 to 37, and various arrangements are possible.

  The light receiving element 31 is a sensor for receiving reflected light irradiated to the identification medium 1 from each of the S1 sensor 34, S2 sensor 35, S3 sensor 36, and S4 sensor 37, and is generally used as a photodiode or phototransistor. CCD elements, CMOS elements, etc. can be used. As the S1 sensor 34 to S4 sensor 37 for irradiating the identification medium 1 with a predetermined wavelength, a commonly used LED or LD (laser diode) can be used.

  Next, a method for identifying the identification medium 1 according to an embodiment of the present invention will be described with reference to FIGS.

  That is, the sensor outputs 44 to 47 of the S1 sensor 34, the S2 sensor 35, the S3 sensor 36, and the S4 sensor 37 move the reading sensor 3 onto the center position (XX ′ in FIG. 1) of the identification medium 1. Sometimes, the relationship between the reflectances of the sensors 34 to 37 is shown in FIG. Therefore, by performing true / false determination by capturing the amount of change in each of the sensor outputs 44 to 47 of the S1 sensor 34, S2 sensor 35, S3 sensor 36, and S4 sensor 37, it is possible to perform more accurate authenticity determination, The identification medium 1 that is difficult to forge can be formed.

  Here, as a method of reading the change in reflectance of each wavelength along the center position on the identification medium 1 by the reading sensor 3, each of the S1 sensor 34 to the S4 sensor 37 is measured independently, and the number of sensors is the same. The sensor output shown in FIG. 6 is generally obtained by reciprocating, but the sensor output shown in FIG. 6 is obtained by causing the sensors of each wavelength to emit light in order and plot the reflectance in the order. You can also This method can shorten the reading time.

  Then, an eddy current sensor (not shown) that detects an eddy current difference between a portion where the non-metallic optical layer 12 is present and a portion where the non-metallic optical layer 12 is present in the identification medium 1 is scanned, and the presence of metal is detected from the detected eddy current difference. Identify. Since the eddy current can be reliably identified without contact, it can be identified even if there is a concealing layer, a protective layer, or the like.

  The eddy current sensor for scanning includes an oscillation coil, and this oscillation coil is connected to an oscillation circuit to generate a high frequency magnetic field in front of the oscillation coil, and generates a high frequency in front of the oscillation coil. In the portion where the metal exists, an eddy current is generated on the surface by electromagnetic induction. This eddy current acts to reduce the oscillation energy of the oscillation coil. As a result, the oscillation amplitude is reduced in the portion where the metal exists.

  Here, the relationship between the position and the output voltage when the eddy current sensor is scanned over the center position (XX ′ in FIG. 1) in the identification medium 1 is as shown in FIG. That is, as described above, the nonmetallic optical layer 12 does not react with the eddy current sensor because it has a characteristic absorption in the near infrared wavelength region but is not a metal layer. Visually, if an attempt is made to imitate with a metal multilayer film even if they are different, scanning with an eddy current sensor lowers the output voltage as shown in FIG. 8, and it is identified that there is a metal layer. As this identification method, it is possible to identify the difference by comparing the difference with the portion without the non-metallic optical layer 12 or by determining whether or not it is within the range by determining a specified value. .

  FIG. 9 shows a main part of an identification medium 5 according to another embodiment of the present invention. In the identification medium 5, a metal pattern layer 13 is provided on the non-conductive substrate 11, and the non-metal optical layer 12 is provided so as to cover the metal pattern layer 13, and is embedded in the non-metal optical layer 12. As described above, the non-metallic optical layer 12 is read by the optical sensor as shown in FIG.

  The metal pattern layer 13 has a metal layer formed in a pattern. For example, the metal pattern layer 13 may be a quadrangle that indicates the presence or absence of a pattern, or may be a code. The substance used for the metal layer may be anything as long as it is a metal, but a substance having high electrical conductivity is preferable. From the viewpoint of reading and workability, for example, the pattern shape can be produced by transferring the pattern shape by applying heat and pressure using an aluminum foil, but other patterns may be used.

  In this embodiment, the relationship between the position when the eddy current sensor (not shown) is scanned and the output voltage has the characteristics shown in FIG. When a portion of the metal pattern layer 13 is scanned with an eddy current sensor, the output voltage is lowered. The determination can be made based on the presence or absence of the metal pattern layer 13, and if the pattern is coded, the code can be recognized from the output voltage scanned by the eddy current sensor. By matching the result of the eddy current sensor with the reading result of the optical sensor 3, it is possible to identify with high accuracy.

  Next, Examples 1 and 2 and Comparative Examples 1, 2, and 3 based on the present invention are manufactured and compared.

Example 1
A non-metallic optical layer mixed with a composition having the following composition was printed on a fine paper by the offset method, and cut into a predetermined size to obtain an identification medium.

[Non-metallic optical layer]
YKR-3081 (manufactured by Yamamoto Kasei Co., Ltd.) 5 parts by weight Black perylene pigment (manufactured by Toda Kogyo Co., Ltd.) 15 parts by weight FD Carton X Medium Lo (manufactured by Toyo Ink) 80 parts by weight (Comparative Example 1)
Using the same base material as in Example 1, a TECSPEC OD2 short pass filter (manufactured by Edmund Optics) was attached as an optical layer to obtain a comparative medium.

(Example 2)
On a high quality paper, as shown in the metal pattern layer shown in FIG. 9, aluminum transfer foil (manufactured by Gream foil Murata Gold Leaf Co., Ltd.) was hot-pressed and transferred in two places in a square shape. On top of that, the same composition of the nonmetallic optical layer as in Example 1 was mixed, and the nonmetallic optical layer was printed on the fine paper by the offset method, and cut into a predetermined size. , Got the identification medium.

(Comparative Example 2)
In the same manner as in Example 2, a non-metallic optical layer was not provided, and a TECSPEC OD2 short pass filter was attached as a metal pattern layer in place of the aluminum transfer foil to obtain an identification medium.

(Comparative Example 3)
In the same manner as in Example 2, an aluminum transfer foil was not provided, and a TECSPEC OD2 short pass filter was attached as an optical layer to the non-metallic optical layer to form an identification medium.

  Although the identification medium obtained in Example 1 was completely different from the Comparative Example 1 in appearance, both optical sensors showed the same results as in FIG. 6, but the output voltage scanned by the eddy current sensor was the same. As a result, Example 1 obtained no peak as shown in FIG.

  Here, although the identification medium of Example 2 was completely different from that of Comparative Example 2, the output voltage scanned with the eddy current sensor was similar to that shown in FIG. However, the sensor intensity scanned by the optical sensor shows the result of the non-metallic optical layer 12 in FIG. 6 in the portion where the metal pattern layer is not formed in Example 2, that is, the output of the eddy current sensor is not lowered. On the other hand, the comparative example 2 showed the result of the nonmetallic optical layer 12 of FIG. 6 in the part with a metal pattern layer, ie, the part where the output of an eddy current sensor falls, and became a different result. Further, in Comparative Example 3, the result of the output voltage scanned by the eddy current sensor is as shown in FIG. 8, and a result different from that in FIG. 10 of Example 2 was obtained.

  The identification medium and the identification method thereof according to the present invention are high in mechanical reading by an optical sensor and an eddy current sensor by providing a non-metallic optical layer having a characteristic absorption different from others in at least a part of the near infrared wavelength region. It was confirmed that accurate authenticity determination can be performed, and that an optical layer using metal can be identified with extremely high forgery resistance.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention in the implementation stage. Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

  For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiment, the problems described in the column of problems to be solved by the invention can be solved, and the effects described in the effects of the invention can be obtained. In some cases, a configuration from which this configuration requirement is deleted can be extracted as an invention.

  According to the present invention, it is possible to make a true / false determination with high accuracy by machine reading with a simple configuration in which a nonmetallic optical layer having a characteristic absorption different from others is provided in at least a part of the near infrared wavelength region. It is possible to provide an identification medium and an identification method with extremely high forgery resistance.

DESCRIPTION OF SYMBOLS 1 ... Identification medium 3 ... Reading sensor 11 ... Nonelectroconductive base material 12 ... Nonmetallic optical layer 13 ... Metal pattern layer 24 ... Wavelength of S1 sensor 25 ... Wavelength of S2 sensor 26 ... Wavelength of S3 sensor 27 ... Wavelength of S4 sensor 31 ... Light receiving element 32 ... Light shielding plate 34 ... S1 sensor 35 ... S2 sensor 36 ... S3 sensor 37 ... S4 sensor 44 ... S1 sensor output 45 ... S2 sensor output 46 ... S3 sensor output 47 ... S4 sensor output 47

Claims (4)

  An identification medium, wherein a nonmetallic optical layer having a characteristic absorption different from the others in at least a part of a near infrared wavelength region is provided on a part of at least one surface of a nonconductive substrate.   The identification medium according to claim 1, wherein a metal pattern layer is embedded in a nonmetallic optical layer on the substrate. An identification method for identifying the identification medium according to claim 1 or 2,
The reflectance of the non-metallic optical layer with respect to a plurality of feature point wavelengths is measured to detect the non-metallic optical layer, and the eddy current is measured at each part on the non-conductive substrate including the non-metallic optical layer An identification medium identification method, wherein authenticity determination is performed by detecting a non-metallic optical layer. An identification method for identifying an identification medium according to claim 2,
Detecting the non-metallic optical layer by measuring the reflectance of the non-metallic optical layer with respect to a plurality of feature point wavelengths, and measuring eddy currents at various parts on the non-conductive substrate including the non-metallic optical layer A method for identifying an identification medium, wherein authenticity determination is performed by detecting the presence or absence of a metal pattern layer in the non-metallic optical layer based on the current difference.

Images