JP2016010857A - Authenticity determination tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an authenticity determination tool with high durability capable of intuitively determining authenticity visually at low cost.SOLUTION: An authenticity determination tool includes a transmitted light observation part having a right-handed circularly polarized light plate or a left-handed circularly polarized light plate, a phase difference plate film laminated in a pattern shape on one surface side of the right-handed circularly polarized light plate or the left-handed circularly polarized light plate, and a transparent protective layer in this order. The authenticity determination tool capable of intuitively determining authenticity visually can be provided at low cost.

Description

  The present invention relates to a true / false determining tool for performing true / false determination of a true / false determining object.

  For example, credit cards, savings cards, various vouchers, or identification cards, etc., cause various troubles if they are counterfeited or tampered with and used improperly, so in order to prevent damage caused by forgery or tampering It is desired to have a function that can identify the authenticity of the. In addition, for example, luxury products such as wristwatches, leather products, precious metal products or jewelry, in particular, what are said to be luxury brand products, audio products, electrical appliances, music software recorded on media, video software, game software, Alternatively, computer software is also subject to counterfeiting, and similarly, it is desired to have a function capable of identifying authenticity.

  Conventionally, holograms are frequently used for the purpose of enabling authenticity identification of various articles including the above-mentioned articles. This is because the hologram has manufacturing difficulties due to the precision of its structure. However, the method of manufacturing a hologram is known to experts, and since it is precise, it is difficult to distinguish between a genuine hologram and a forged hologram.

  Therefore, as an alternative to a hologram, for example, in Patent Document 1, only one of left-handed polarized light and right-handed polarized light among incident light formed on one surface of the base material and the base material is used. A true / false judgment body having a light selective reflection layer that reflects light and a judgment unit that is formed on at least part of the light selective reflection layer and has judgment information for judging a new product, and a true / false judgment tool using a circularly polarized plate Has been proposed.

  Further, in Patent Document 2, the two light selective reflection layers have a laminated structure in which the two layers are laminated via a retardation layer, and the two light selective reflection layers are configured to receive incident light. The center wavelength of the reflected light of the two layers of light selective reflection layers, which is either left circularly polarized light or right circularly polarized light and is composed of a material having light selective reflection property that reflects circularly polarized light in the same direction. The light diffractive structure layer is laminated on one surface of the laminated structure, and the light diffractive structure layer is a layer with a reflection hologram or a light reflective layer. And a true / false determining body and a true / false determining tool using a circularly polarized plate have been proposed.

  However, it is difficult for the observer to intuitively determine whether the true / false determination object is “true” or “false” with the authenticity determination tools such as Patent Documents 1 and 2. In the present specification, “true” means that the authenticity determination object is genuine, and “false” means that the authenticity determination object is not authentic.

  Patent Document 3 describes an authenticity determination body having a liquid crystal layer that functions as a half-wave plate provided with a predetermined pattern on a cholesteric liquid crystal layer, and passes through a circular polarizing filter that is an authenticity determination tool. An identification medium has been proposed in which a predetermined pattern can be recognized by a predetermined color and black.

  However, it is necessary for such a true / false determination object to create the predetermined pattern indicating “true” in each medium, and it is difficult to reduce the cost for the true / false determination.

JP 2000-25373 A Japanese Patent No. 4390265 WO2007 / 116844

  The subject of this invention is providing the authenticity determination tool with high durability.

  The “true / false judgment” of the present invention refers to an operation for judging whether the true / false judgment object is “true” or “false”, and the “observer” means whether the true / false judgment object is “true”. A judge who visually verifies whether it is “false”. A “true / false judgment tool” is a tool used to judge whether a true / false judgment object is “true” or “false”. The “true / false judgment object” refers to an article for which a true / false judgment is made as to whether it is “true” or “false”.

  A first invention of the present invention includes a right circularly polarizing plate or a left circularly polarizing plate, a retardation film laminated in a pattern on one surface side of the right circularly polarizing plate or the left circularly polarizing plate, and a transparent protective film The present invention relates to a true / false determining tool including a transmitted light observation unit having layers in this order.

  The retardation film may be a half-wave plate film.

  A second invention of the present invention is a first transmission comprising a right circularly polarizing plate, a retardation film laminated in a pattern on one surface side of the right circularly polarizing plate, and a transparent protective layer in this order. A second observation portion having a light observation portion, a left circularly polarizing plate, a retardation film laminated in a pattern on one side of the left circularly polarizing plate, and a transparent protective layer in this order; It is related with the authenticity determination tool characterized by providing.

  The retardation plate film of the first transmitted light observation unit and the retardation plate film of the second transmitted light observation unit may be half-wave plate films.

  According to the present invention, it is possible to provide an authenticity determination tool with high durability.

(A), (b) It is the schematic which shows an example of the form of a true / false determination tool, and a schematic sectional drawing. (A), (b) It is the schematic which shows an example of the form of a true / false determination tool, and a schematic sectional drawing. (A) It is the schematic which shows an example of a truth determination body. (B) It is the schematic which shows an example of the image which can be observed through the authenticity determination tool. (A) It is the schematic which shows an example of a truth determination body. (B) It is the schematic which shows an example of the image which can be observed through the authenticity determination tool. (A), (b) It is a schematic sectional drawing which shows an example of the form of the authenticity determination tool which has a hologram layer.

  The present embodiment relates to a true / false determination tool that allows an observer to make a true / false determination by visual observation. A pattern such as a character or a symbol is displayed and can be used for a long period of time so that an intuitive authenticity determination is possible. It is intended to provide a authenticity determination tool with high durability.

Generally, the authenticity determination is performed using an extremely small number of authenticity determination tools for an extremely large number of authenticity determination objects. The processing cost can be reduced by performing processing for forming the authenticity determination information in a pattern on a small number of the authenticity determination tools, not on an overwhelmingly large number of the authenticity determination bodies. it can.
Moreover, by having a transparent protective layer, the retardation plate film can be prevented from being damaged, and a highly authentic authenticity determination tool that can be used for a long period of time can be provided. In addition, the transparent protective layer makes it difficult to understand the presence of the retardation film that serves as a criterion for authenticity determination, and makes it difficult to easily confirm the principle of authenticity determination.

1. Authenticity determination The authenticity determination tool of this embodiment is used for an observer to observe reflected light from an authenticity determination body and perform authenticity determination. The authenticity determination body using the authenticity determination tool of this embodiment has one or two specific wavelengths and reflects light having a specific circular polarization property.

1-1. When the reflected light is one type As shown in FIGS. 3 (a) and 5 (a), the true / false determination object has a specific wavelength on the right or right of the incident natural light by the light selective reflection layer 41. The true / false determination in the case of using the authenticity determination body 2 that reflects the left circularly polarized light will be described.

  A description will be given assuming that the light selective reflection layer of the authenticity determination body is formed of a material that reflects red right circularly polarized light.

The red right circularly polarized light is incident on the authenticity determination tool from the side opposite to the observer.
Here, when the transmitted light observation part of the authenticity determination tool has a circularly polarizing plate that allows right-handed circularly polarized light to pass therethrough, and the retardation film is formed in a pattern shape of “True”, the observer has a red background. In addition, a pattern “True” as shown in FIG. 3B displayed in dark red, black, or gray close to black can be observed. When the true / false judgment object is “false” and the reflected light is not selected, the pattern cannot be observed.

  When the transmitted light observation part of the authenticity determination tool has a circularly polarizing plate that allows right-handed circularly polarized light to pass therethrough, and the retardation film is formed with a hollow pattern of “True”, the observer is dark red, A pattern “True” displayed in red on a black background or a gray background close to black can be observed. When the true / false judgment object is “false” and the reflected light is not selected, the pattern cannot be observed.

  When the light selective reflection layer of the authenticity determination body is formed of a material that reflects red left and right circularly polarized light, the appearance is opposite to that described above.

  In order to recognize the pattern of the retardation film more clearly, it is preferable that the retardation film of the transmitted light observation part is a half-wave plate film. This is because if the retardation film is a half-wave plate film, the right circularly polarized light that has passed through the half-wave plate film becomes left-handed circularly polarized light and cannot pass through the circularly polarizing plate that passes the right-hand circularly polarized light.

The reflected light from the true / false judgment body reflects only one direction of circularly polarized light with only a specific wavelength, and the retardation plate film of the true / false judgment tool is a perfect half-wave plate film. If the circularly polarizing plate of the determination tool is in an ideal state where only the circularly polarized light in one direction passes, the pattern of the half-wave plate film is observed in black on the background of the color of the light having the specific wavelength. .
However, the authenticity determination body and the authenticity determination tool that can be actually manufactured have variations in the wavelength and phase of light. For this reason, even if the phase difference plate film is not a complete half-wave plate film, the observer can determine the authenticity by observing the transmitted light of the authenticity determination tool.

1-2. When there are two types of reflected light As shown in FIG. 4 (a) and FIG. 5 (b), the authenticity judgment body is a circle in one direction of right or left at a specific wavelength with respect to incident natural light. When the authenticity determination body 2 that reflects the polarized first reflected light and the second reflected light that is different in wavelength from the specific wavelength and circularly polarized in the same direction as the circularly polarized light is used. The authenticity determination will be described.

  The case where the first light selective reflection layer of the authenticity determination body is formed of a material that reflects red right circularly polarized light, and the second light selective reflection layer is formed of a material that reflects blue left circularly polarized light. An explanation will be given.

  Red right-circular first reflected light and blue left-circular second reflected light are incident on the authenticity determination tool from the side opposite to the observer. Here, the first transmitted light observation unit of the authenticity determination tool includes a circularly polarizing plate that transmits right circularly polarized light, and the second transmitted light observation unit includes a circularly polarizing plate that transmits left circularly polarized light, In the case where the retardation film is formed in a pattern of “O” in the transmitted light observation part 1 and “K” in the second transmitted light observation part, the observer transmits the first transmitted light observation part as follows: Only the first reflected light is transmitted, and the retardation film mainly transmits the second reflected light. Therefore, as shown in FIG. 4B, blue or blue and red are synthesized on a red background. The pattern “O” displayed in a different color can be observed. For the same reason, the second transmitted light observation unit observes a pattern “K” displayed by combining red and blue and red on a blue background as shown in FIG. 4B. be able to. If the true / false judgment is “false”, the reflected light is not selected and the circularly polarized light is not reflected, the pattern cannot be observed.

  In order to recognize the pattern of the retardation film more clearly, it is preferable that the retardation film of the transmitted light observation part is a half-wave plate film. The reason is the same as when the reflected light is one type.

2. Authenticity determination tool An example of the authenticity determination tool of this embodiment is shown in FIG. In the example illustrated in FIG. 1A, the authenticity determination tool 10 includes a transmitted light observation unit 10 and a frame 20 that supports the transmitted light observation unit 10. In the authenticity determination tool of this embodiment, the frame body 20 may not be provided as long as the transmitted light observation unit 10 has such a high rigidity that there is no problem in handling. In order to prevent the occurrence of scratches and scratches, it is preferable to have the frame body 20.

  The transmitted light observation unit 10 includes a right circular polarizing plate or a left circular polarizing plate 31, a retardation film 32 laminated in a pattern on one surface side of the right circular polarizing plate or the left circular polarizing plate 31, and a transparent plate. Protective layers 35 are provided in this order. When the authenticity determination tool 1 is used for authenticity determination, as shown in FIG. 1B, the surface of the circularly polarizing plate 31 faces the observer side and the surface of the phase difference plate film 32 faces the authenticity determination body side. To use.

  When the retardation film 32 is a half-wave plate film, the state of transmission and blocking of reflected light approaches an ideal state, so that the pattern can be recognized more clearly.

  Further, as shown in FIG. 1A, the authenticity determination tool 1 of the present embodiment has a first transmitted light observation unit and a second transmitted light observation unit in one transmitted light observation unit 10. As shown in FIG. 2A, the frame 20, the first transmitted light observation unit 11 supported by the frame 20, and the second transmitted light observation unit 12 are provided. You may have. In the authenticity determination tool of this embodiment, the frame body 20 may not be provided as long as the transmitted light observation unit 10 has such a high rigidity that there is no problem in handling. In order to prevent the occurrence of scratches and scratches, it is preferable to have the frame body 20.

  When the authenticity determination tool 1 includes the first transmitted light observation unit 11 and the second transmitted light observation unit 12, the first transmitted light observation unit 11 has either a right or left circular polarization property. The second transmitted light observation unit 12 includes a circularly polarizing plate 34 having a circular polarization property opposite to that of the circularly polarizing plate 33 used in the first transmitted light observation unit 11. It is preferable to have.

  The first transmitted light observation unit 11 and the second transmitted light observation unit 12 are respectively a circularly polarizing plate and a retardation film laminated in a pattern on one surface side of the circularly polarizing plate, Have When the authenticity determination tool 1 is used for authenticity determination, as shown in FIG. 1B, the surface of the circularly polarizing plate 31 faces the observer side and the surface of the phase difference plate film 32 faces the authenticity determination body side. To use.

  The polarization directions of the circularly polarizing plates used in the transmitted light observation unit 10, the first transmitted light observation unit 11, and the second transmitted light observation unit 12 are as shown in FIGS. 3A and 4A, for example. It can be arbitrarily selected based on the polarization direction of the reflected light from the true / false determination object and the selection of the display color in the transmitted light observation unit 10.

  The frame 20 only needs to have a function for holding the transmitted light observation unit 10, the first transmitted light observation unit 11, and the second transmitted light observation unit 12, and only the transmitted light observation unit 10. However, when the frame body 20 is not necessary due to sufficient rigidity for handling, the frame body 20 may be omitted. Moreover, the frame 20 should just have a function for hold | maintaining the transmitted light observation part 10, and what kind of material may be used for it. In view of ease of handling, ease of manufacture, cost, etc., it is preferable to use a plastic sheet or cardboard.

  Further, the transmitted light observation unit 10 may be fixed to one surface of a frame 20 having a hole as shown in FIG. 1A, and is fixed by being sandwiched between two frames. May be.

3. Transmitted light observation part The transmitted light observation part has a circularly-polarizing plate and a retardation film in order from the observer side as described above.

3-1. Circularly polarizing plate The circularly polarizing plate has a linearly polarizing film and a quarter-wave plate.

3-1-1. Linear Polarizing Film The linear polarizing film only needs to have a linear polarizing function, and iodine-based polarizing films, dye-based polarizing films and the like used in liquid crystal displays and the like can be used.

3-1.2.1 / 4 Wave Plate Layer A right circularly polarizing plate can be formed by combining the optical axis of the quarter wave plate at +45 degrees with respect to the absorption axis of the linearly polarizing film, and −45 degrees. In combination, a left circularly polarizing plate can be formed.

3-2. Retardation plate film A retardation plate film changes the phase of the incident light by transmitting light through the retardation plate film. When the retardation film is a half-wave plate film, the incident right circularly polarized light is left circularly polarized light, the incident left circularly polarized light is right circularly polarized light, and so on. Can be reversed.

  A film material having birefringence can be used for such a retardation film. In the case of forming a half-wave plate film, the film thickness of the birefringent material may be adjusted to form a thickness that can generate a half-wave retardation. For example, a birefringent film such as a PET film, a polycarbonate, or a cellophane film can be used. When a PET film is used, the thickness is preferably 25 to 100 μm in view of visibility and workability (ease of sticking).

  In this embodiment, the retardation film 32 is laminated in a pattern. The pattern of the retardation film 32 may be any pattern as long as it is determined in advance whether it is “true” or “false”. It is preferable that a pattern capable of visually determining “true” or “false” is formed. For example, as shown in FIGS. 3B and 4B, characters such as “True” and “OK” may be used, and symbols such as “◯” may be used.

3-3. Transparent protective layer The transparent protective layer has a concealing effect that protects the polarizing plate and the retardation film from being damaged and makes the presence of the retardation film difficult to understand. Since the light transmitted through the transparent protective layer is observed through the polarizing plate and the retardation film, the transparent protective layer is not only a function that can prevent scratches, but has a low birefringence, It is required that the phase of transmitted light is not affected as much as possible. Such a transparent protective layer can be formed by a coating method using a urethane resin, a vinyl acetate resin, an acrylic resin, or the like. The thickness of the transparent protective layer is preferably larger than the thickness of the retardation film and not more than (thickness of the retardation film + 100 μm). If it is thinner than the thickness of the retardation film, the concealing effect of the retardation film is lowered. On the other hand, if it is not less than (thickness of retardation plate film + 100 μm) or less, cracks are likely to occur.

4). Authenticity determination body The authenticity determination body using the authenticity determination tool of the present embodiment for authenticity determination may reflect a specific circularly polarized light.

  For example, as shown in FIG. 3A, the authenticity determination body 2 that reflects right or left circularly polarized light having a specific wavelength by the light selective reflection layer 41 can be used for incident natural light. .

  For such a light selective reflection layer 41, for example, polymer cholesteric liquid crystal can be used. If necessary, a chiral agent and an ultraviolet polymerization initiator may be included.

  In addition to the cholesteric liquid crystal layer, the light selective reflection layer can be configured by using, for example, a pigment whose color changes depending on the viewing angle, a vapor deposition thin film, or a dichroic dye. Examples of pigments whose color changes depending on the viewing angle include pearl pigments in which layers of high refractive index silicon oxide, titanium oxide, iron oxide, and the like, and layers of low refractive index mica, etc. are laminated. Are available under the trade names of Shiseido Co., Ltd .; Infinite Color and Merck (Germany); The deposited thin film is formed by forming a metal such as aluminum or other material as a thin film by a vapor phase method, and exhibits a so-called interference color like an oil thin film floating on the water surface. A dichroic dye is composed of long-chain dye molecules that have different light absorption depending on the direction of the molecular axis. For example, the light component in the normal direction relative to the direction of the molecular axis of the dye molecule has almost no absorption. The light component in the direction parallel to the direction of the molecular axis has an absorptive property and does not transmit light, and examples include anthraquinone, azo, or bisazo dyes. can do.

  Further, as shown in FIG. 4A, the authenticity determination body 2 having the first light selective reflection layer 43, the base material 45 having the function of a half-wave plate, and the second light selective reflection layer 44. Can be used. The authenticity determination body 2 reflects right circularly polarized light having a specific wavelength with respect to incident natural light by the first light selective reflection layer 43, and what is the specific wavelength by the first light selective reflection layer 43. The direction of the circularly polarized light is reversed by reflecting the right circularly polarized light having a different wavelength and passing through the base material 45 having the function of a half wavelength plate. The authenticity determination body 2 reflects right circularly polarized light having a specific wavelength and left circularly polarized light having a wavelength different from the specific wavelength as a whole function.

  For the first light selective reflection layer and the second light selective reflection layer, the same materials as those used for the light selective reflection layer can be used.

  The authenticity determination body 2 may have a light absorption layer on the side opposite to the reflection surface of the authenticity determination body 2 in order to prevent unnecessary reflection of light. The light absorption layer in the previous period reduces unnecessary light reflection and facilitates authenticity determination.

  The authenticity determination body 2 may have a reflection layer formed in a pattern on the opposite side of the reflection surface of the authenticity determination body 2 in order to further improve security. ), (B), a hologram layer may be provided on the side opposite to the reflecting surface of the authenticity determination body 2. Furthermore, the reflection layer of the hologram layer may be formed in a pattern.

[Example 1]
A circular polarizing plate was fixed between the two PET films by using a frame in which two 300 μm thick white PET (polyethylene terephthalate) films were bonded together. The circularly polarizing plate was prepared by bonding the optical axis of a quarter wavelength plate to a linearly polarizing film at +45 degrees with respect to the absorption axis of the linearly polarizing film. As a retardation film, a cellophane film with a thickness of 25 μm formed in the shape of “True” was attached to the opposite side of the right circularly polarizing plate with an adhesive. In addition, a transparent protective layer was formed by a printing method or a coating method to produce a true / false determination tool. The transparent protective layer includes a THF (tetrahydrofuran) primer manufactured by DIC Graphics, SG740 800 medium manufactured by Seiko Advance, SE-11 (P) medium manufactured by Showa Ink Industry Co., Ltd., and ACRYDEC A-801 manufactured by DIC Graphics. Four kinds of authenticity determination tools were formed so that the thickness of each of −P was 25 μm.

  As a result of observing the authenticity determination body having the characteristic of reflecting the right-wave-polarized red wavelength with respect to natural light using the four kinds of authenticity determination tools, the transmitted light observation units of all the authenticity determination tools On the red background, a gray “True” character close to black was confirmed. As a result of observing the authenticity determination body having no characteristics in the reflected light, information could not be confirmed in the transmitted light observation part of the authenticity determination tool.

[Example 2]
Using a frame having a first transmitted light observation part and a second transmitted light observation part in which two 300 μm thick PET (polyethylene terephthalate) films are bonded together, a circularly polarizing plate is provided between the two PET films. Fixed. The circularly polarizing plate fixed to the first transmitted light observation unit is a right circularly polarizing plate in which the optical axis of a quarter wave plate is bonded to a linearly polarizing film at +45 degrees with respect to the absorption axis of the linearly polarizing film. Using. For the circularly polarizing plate fixed to the second transmitted light observation part, a left circularly polarizing plate in which the optical axis of a quarter-wave plate is bonded to the linearly polarizing film at −45 degrees with respect to the absorption axis of the linearly polarizing film. Was used. In the first transmitted light observation part, a cellophane film having a thickness of 25 μm formed in a letter “O” shape as a retardation film is attached to the opposite side of the right circularly polarizing plate with an adhesive. I attached. Furthermore, a protective layer was formed to produce a true / false determination tool. In the second transmitted light observation part, a cellophane film with a thickness of 25 μm formed as a letter “K” as a retardation film is pasted on the opposite side of the right circularly polarizing plate with an adhesive. I attached. Furthermore, a transparent protective layer was formed to produce a true / false determining tool. A first transmitted light observation unit; The transparent protective layer formed in the second transmitted light observation part was formed using four types of materials as in Example 1.

  Using the four kinds of authenticity determination tools, an authenticity determination body having the characteristic of reflecting the right-handed circularly polarized red wavelength and the left-handed circularly-polarized blue wavelength with respect to natural light was observed. As a result, in the first transmitted light observation unit of all the authenticity determination tools, a blue “O” character could be confirmed on the red background. Further, in all the second transmitted light observation units, it was possible to confirm the red “K” character on the blue background. As a result of observing the authenticity determination body having no characteristics in the reflected light, information could not be confirmed in both the first transmitted light observation unit and the second transmitted light observation unit of the authenticity determination tool.

DESCRIPTION OF SYMBOLS 1 Authenticity determination tool 10 Transmitted light observation part 11 1st transmitted light observation part 12 2nd transmitted light observation part 20 Frame 31, 33, 34 Circularly-polarizing plate 32 Phase difference plate film 35 Transparent protective layer 2 Authenticity Determination body 41 Light selective reflection layer 42 Base material 43 First light selective reflection layer 44 Second light selective reflection layer 45 Base material (1/2 wavelength plate)
3 Hologram layer

Claims (4)

  Right circularly polarizing plate or left circularly polarizing plate, retardation plate film laminated in a pattern on one side of the right circularly polarizing plate or left circularly polarizing plate, and transmitted light observation having a transparent protective layer in this order The authenticity determination tool characterized by including a part.   The authenticity determination tool according to claim 1, wherein the retardation film is a half-wave plate film. A first circularly polarizing plate, a phase difference plate film laminated in a pattern on one surface side of the right circularly polarizing plate, and a first transmitted light observation unit having a transparent protective layer in this order;
A left circularly polarizing plate, a retardation film laminated in a pattern on one side of the left circularly polarizing plate, and a second transmitted light observation unit having a transparent protective layer in this order;
The authenticity determination tool characterized by comprising. 4. The retardation film of the first transmitted light observation unit and the retardation film of the second transmitted light observation unit are half-wave plate films, according to claim 3. Authenticator.

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