JP2020075487A - Multilayer body, authenticity discrimination method, authenticity discrimination system, and program - Google Patents

Abstract

To provide: a multilayer body having an improved forgery prevention property; a method for discriminating authenticity thereof; an authenticity discrimination system; and a program which can be incorporated into the system.SOLUTION: The multilayer body comprises a resin layer (A) containing a first illuminant and a resin layer (B) containing a laser beam energy absorber and, further, satisfies at least one of the following (1) and (2): (1) the resin layer (B) contains a second illuminant which is different from the first illuminant; and (2) the multilayer body further comprises a resin layer (C), and the resin layer (C) is positioned on a side of the resin layer opposite to the resin layer (A) and contains the second illuminant different from the first illuminant.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a multi-layer body, an authenticity determination method, an authenticity determination system, and a program.

  Conventionally, resin films have been used in ID cards, e-passports, IC cards and the like. As such a resin film, a laser marking film capable of printing a specific area by irradiation with laser light is known (see Patent Document 1).

WO2010 / 089035

By the way, various personal authentication cards and the like have personal information printed thereon. Such cards have a problem that the print is easily scraped and forged. In the laser marking film exemplified in the above-mentioned Patent Document 1, the inner layer of the laminated film can be printed or drawn by laser engraving. Therefore, it is improved from the viewpoint of preventing forgery as compared with the conventional one that is printed or drawn on the surface. However, since the information can be visually confirmed, there is a problem that the effect of preventing forgery is limited. In addition, there was a problem that the contents could be tampered with by additionally performing laser marking.
Therefore, it is an object of the present invention to provide a multi-layered body with improved anti-counterfeiting property, a method of authenticating the same, a system of authenticity determination, and a program that can be incorporated into this system.

The above problems have been solved by the following means.
<1> A resin layer (A) containing a first light emitter and a resin layer (B) containing a laser light energy absorber, and further satisfying at least one of the following (1) and (2). , Multilayers;
(1) The resin layer (B) contains a second luminous body different from the first luminous body;
(2) Further, a resin layer (C) is provided, the resin layer (C) is located on the opposite side of the resin layer (B) from the resin layer (A), and the first light emitting body is provided. Contains a different second illuminant.
<2> The multilayer body according to <1>, which satisfies the above (1).
<3> The multilayer body according to <1> or <2>, which satisfies the above (2).
<4> The second luminescent material according to any one of <1> to <3>, which is at least one kind selected from luminescent materials excited by at least one of ultraviolet light and infrared light. Multi-layered body.
<5> Any one of <1> to <4>, wherein the first luminous body and the second luminous body are at least one kind selected from luminous bodies excited by light supplied from the same light source. The multilayer body according to item 1.
<6> The first luminescent material according to any one of <1> to <5>, wherein the first luminescent material is at least one selected from luminescent materials excited by at least one of ultraviolet light and infrared light. Multi-layered body.
<7> The multilayer body according to any one of <1> to <6>, in which the resin layer (A) contains at least one of a polycarbonate resin and a polyester resin.
<8> The at least one of the resin layer (B) and the resin layer (C) contains at least one of a polycarbonate resin and an amorphous polyester resin, according to any one of <1> to <7>. Multilayer body.
<9> The first luminous body is B, F, Mg, Al, Si, P, S, Cl, Ca, V, Mn, Cu, Zn, Ge, Sr, Y, Ba, La, Ce, Pr. , Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, including an element selected from the group consisting of <1> to <8>. Multilayer body.
<10> The second luminous body is B, F, Mg, Al, Si, P, S, Cl, Ca, V, Mn, Cu, Zn, Ge, Sr, Y, Ba, La, Ce, Pr. , Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu, containing an element selected from the group consisting of <1> to <9>. Multilayer body.
<11> The multilayer body according to any one of <1> to <10>, which is used for authenticity determination.
<12> The multilayer body according to any one of <1> to <11>, which is a security card.
<13> The multilayer body according to any one of <1> to <12>, in which a laser marking process is performed on the resin layer (B).
<14> The multilayer body according to any one of <1> to <13>, further including a light shielding layer.
<15> The multilayer body according to <14>, wherein the light shielding layer contains a white pigment or a black pigment.
<16> After the laser marking treatment is performed on the resin layer (B) of the multilayer body according to any one of <1> to <15>, each of the first light emitter and the second light emitter is caused to emit light. A method for determining the authenticity of a multilayer body, which comprises irradiating a specific light capable of performing.
<17> The authenticity determination method according to <16>, wherein the wavelength of the specific light is in the range of 200 to 450 nm.
<18> The authenticity determination method according to <16>, wherein the wavelength of the specific light is in the range of 800 to 10,000 nm.
<19> The authenticity determination method according to any one of <16> to <18>, wherein the multilayer body is a security card.
<20> The multilayer body according to any one of <1> to <15>, wherein the multilayer body after laser marking is irradiated with specific light to cause the multilayer body to emit light. When the light emitted by the irradiation unit and the multilayer body after the laser marking processing is matched with the light emitted by the multilayer body after the pre-registered laser marking processing, the multilayer body An authenticity determination system having an authenticity determination unit that determines that the light emitted by the is authentic light.
<21> The light emitted by the multilayer body after the pre-registered laser marking treatment is performed is the light emitted by the laser marking non-treatment portion and the light emitted by the laser marking treatment portion having a specific optical density. The authenticity determination system according to <20>, including.
<22> A program written in a computer-readable format, the step of detecting light emitted by the multilayer body according to any one of <1> to <15>, and the multilayer body emitting light. When the registered light matches the light emitted by the multilayer body after the pre-registered laser marking process is performed, the authenticity determining step of determining that the light emitted by the multilayer body is authentic light. A program for causing a computer to execute the processing including.

  According to the present invention, it is possible to provide a multi-layered body with improved anti-counterfeiting property, its authenticity judging method, an authenticity judging system, and a program which can be incorporated in this system.

It is sectional drawing which shows typically an example of the multilayer body which concerns on preferable embodiment of this invention. It is sectional drawing which shows typically another example of the multilayer body which concerns on preferable embodiment of this invention. It is sectional drawing which shows typically another example of the multilayer body which concerns on preferable embodiment of this invention. It is sectional drawing which shows typically another example of the multilayer body which concerns on preferable embodiment of this invention. It is sectional drawing which shows typically another example of the multilayer body which concerns on preferable embodiment of this invention. It is sectional drawing which shows typically another example of the multilayer body which concerns on preferable embodiment of this invention. It is sectional drawing which shows typically another example of the multilayer body which concerns on preferable embodiment of this invention. It is sectional drawing which shows typically another example of the multilayer body which concerns on preferable embodiment of this invention. It is sectional drawing which shows typically an example of the multilayer body of the comparative example of this invention. It is sectional drawing which shows typically another example of the multilayer body of the comparative example of this invention. It is sectional drawing which shows typically another example of the multilayer body of the comparative example of this invention. It is sectional drawing which shows typically another example of the multilayer body of the comparative example of this invention. It is sectional drawing which shows typically another example of the multilayer body of the comparative example of this invention. It is sectional drawing which shows typically another example of the multilayer body of the comparative example of this invention. It is sectional drawing which shows typically another example of the multilayer body of the comparative example of this invention. It is a flowchart which shows an example of the authenticity determination method using the multilayer body which concerns on preferable embodiment of this invention. 17 is a part of a flowchart showing a modified example of the authenticity determination method shown in FIG. 16. It is an apparatus block diagram which shows an example of the authenticity determination system which concerns on preferable embodiment of this invention.

  Hereinafter, the present invention will be described in detail. It should be noted that the present invention is not limited to the following embodiments and can be implemented by being arbitrarily modified within the scope of the effects of the invention.

The multilayer body of the present invention has a resin layer (A) containing a first luminous body and a resin layer (B) containing a laser light energy absorber, and further comprises the following (1) and (2): Meet at least one.
(1) The resin layer (B) contains a second luminous body different from the first luminous body.
(2) Further, a resin layer (C) is provided, the resin layer (C) is located on the opposite side of the resin layer (B) from the resin layer (A), and the first light emitting body is provided. Contains a different second illuminant.

FIG. 1 is a sectional view schematically showing an example of a multilayer body according to a preferred embodiment of the present invention.
The multilayer body of the present embodiment includes a purple light-emitting film 1 that emits violet light in response to a first light (light ray 1) and a yellow-green LM that emits yellow-green light in response to the first light (light ray 1). And a film 23. The purple light emitting film 1 contains a purple light emitter (first light emitter) which emits purple light in response to a first light. The yellow-green LM film 23 absorbs the yellow-green light-emitting body (second light-emitting body) which emits yellow-green light in response to the first light, and the laser light, and the energy thereof causes the matrix resin to turn black. It contains a laser light energy absorber (for example, a laser marking agent is exemplified). In the present embodiment, before the laser light energy absorber is irradiated with the laser light (before the laser marking process), when the first light (light ray 1) is irradiated, the violet light emitter and the yellow-green light emitter are separated. Both glow and appear white. On the other hand, even when the second light (light ray 2) is irradiated, the violet luminescent material and the yellow-green luminescent material do not emit light, and the color of the thermoplastic resin is directly visible. If the thermoplastic resin is, for example, a polycarbonate resin or an amorphous polyester resin, it looks so-called transparent. In addition, in this specification, "transparent" means that the value of the total light transmittance defined by ISO13468-1: 1996 shows 50% or more. Further, in the case where other components are added to the thermoplastic resin within the range not departing from the gist of the present invention, the color of the thermoplastic resin including the additive can be confirmed.
On the other hand, after being irradiated with the laser light (after the laser marking process), the yellow-green LM film 23 is usually discolored to black at the portion irradiated with the laser light. Therefore, when the first light (light ray 1) is irradiated, the laser marking processing part emits a purple luminescent material on the black region, and shows a slightly dark purple. On the other hand, the non-laser marking treated portion remains white.
On the other hand, when the second light (light ray 2) is irradiated, the purple light-emitting film 1 and the yellow-green LM film 23 do not emit light in the laser marking non-treated portion, so that the color of the thermoplastic resin as it is can be confirmed. .. On the other hand, the laser marking processing part receives the irradiation of the laser beam and usually looks black.
Unless otherwise stated, all the cross-sectional views of the multilayer body are premised on visual inspection or detection on the drawings (the same applies to the following drawings).

As described above, according to the multilayer body of the present embodiment, the colors detected by the emission of the first light (light ray 1) are different before and after the laser marking process. Therefore, the laser marking process can give an irreversible change to the emission color of the multilayer body, which can be used for authenticity determination. Further, by stacking the multilayer body of the present embodiment on the already written true information portion, it is possible to distinguish it from the already written true information portion with respect to the additional forgery laser marking process. As a result, additional counterfeit laser marking processing can be prevented.
The authenticity determination method and the like utilizing such a property will be described later, but a typical advantage is that the laser-marked portion has a predetermined color because the color of light emitted by the multilayer body is different. Irradiation with light of a wavelength changes the color of the multilayer body. By utilizing this, for example, as will be described later, there is a mode in which the information of the emission color (light) after the laser marking process is recorded in advance. By doing this, when it becomes necessary to confirm the card (example of multi-layered body), laser marking processing is performed, and the emitted color (light) at that time is compared with the recorded emitted color (light), so that the card It can be confirmed by a simple and non-destructive method whether or not the product is forged.

FIG. 2 is a sectional view schematically showing another example of the multilayer body according to the preferred embodiment of the present invention.
The multilayer body shown in FIG. 2A emits yellowish green LM film 23 that emits yellowish green light in response to the first light (ray 1) and emits purple light in response to the first light (ray 1). And a purple light emitting film 1. The yellow-green LM film 23 and the purple light-emitting film 1 are the same as those in the embodiment shown in FIG. In the multilayer body shown in FIG. 2 (a), before the laser light energy absorber is irradiated with the laser light (before the laser marking process), when the first light (light ray 1) is irradiated, the yellow-green luminous body is emitted. Both the and the purple illuminants emit light and appear white. On the other hand, even when the second light (light ray 2) is irradiated, the yellow-green luminescent material and the violet luminescent material do not emit light, and the color of the thermoplastic resin is directly visible.
In the embodiment shown in FIG. 2, after the laser marking process, the yellow-green LM film 23 is partly turned black in the thickness direction. Therefore, when the first light (light ray 1) is irradiated, the yellow-green light emitting body emits light on the black region 30 in the laser marking processing part, and exhibits a slightly dark yellow-green color. On the other hand, the non-laser marking treated portion remains white.

FIG. 3 is a sectional view schematically showing another example of the multilayer body according to the preferred embodiment of the present invention.
The multilayer body of the present embodiment responds to a first light (light ray 1), which emits purple light in a purple color, a laser marking film 3 including a laser light energy absorber, and a first light. And a yellow-green light-emitting film 2 which emits yellow-green light in this order. The aspect of the purple light emitting film 1 is the same as that of FIG. The laser marking film 3 contains a laser light energy absorber, and the laser marking processing part normally turns black. The yellow-green light-emitting film 2 contains a yellow-green light-emitting body that emits yellow-green light in response to the first light, and emits yellow-green light when irradiated with the first light.
Before the laser marking process, the multilayer body of this embodiment emits purple light of the purple light emitting film 1 and yellow green light of the yellow green light emitting film 2 by the irradiation of the first light, and thus appears white. On the other hand, after the laser marking process, the laser marking film 3 is usually discolored to black, and therefore, when the first light is irradiated, the yellow-green light emission intensity from the yellow-green light emitting film 2 therebelow is emitted. Becomes weak. As a result, the purple emission contribution of the purple emitting film on the black laser marking film is enhanced. That is, in the same manner as in the embodiment of FIG. 1, the treated multilayer body exhibits a slightly dark purple color by the irradiation of the first light.
On the other hand, when the light (second light) that the violet light emitter and the yellow-green light emitter do not emit is irradiated, the color of the thermoplastic resin can be seen as it is in the laser marking non-treated portion as in FIG. The processing section usually looks black upon being irradiated with the laser beam.

FIG. 4 is a sectional view schematically showing another example of the multilayer body according to the preferred embodiment of the present invention.
The multilayer body of the present embodiment has a light emitting film 11, a laser marking film 3, and a light emitting film 21 in that order. The light-emitting film 11 responds to a yellow-green luminous body (light ray 1) that emits yellowish green light in response to the first light (light ray 1) and the first light (light ray 1) and the second light (light ray 2). And a red light emitter (light ray 2) that emits red light. The luminescent film 21 responds to the first light (ray 1) in response to the violet emitter (ray 1) that emits violet and the first light (ray 1) and the second light (ray 2). And a luminescent material that is a mixture of blue and green that emits light in blue and green. A laser marking film is sandwiched between upper and lower layers to combine light emitters that emit different colors in response to different light.
In the multilayer body of the present embodiment, the film 11 emits orange light and the film 21 emits blue light and appears white by the irradiation of the first light before the laser marking process. On the other hand, after the laser marking process, the laser marking film 3 is normally discolored to black, so that even if the first light is irradiated, the blue emission intensity of the film 21 thereunder becomes weak. As a result, the orange emission on the black laser marking film will be strongly detected. That is, the irradiation of the first light causes the treated multilayer body to have a slightly dark orange color.
On the other hand, by the irradiation of the second light, before the laser marking process, in the multilayer body, the film 11 emits red light, the film 21 emits blue green light, and white appears. On the other hand, after the laser marking process, since the laser marking film 3 is discolored to black, even if the second light is irradiated, the emission intensity of blue-green from the film 21 thereunder becomes weak. As a result, the red emission on the black laser marking film will be strongly detected. That is, the irradiation of the second light causes the treated multilayer body to have a slightly dark red color.

FIG. 5 is a sectional view schematically showing another example of the multilayer body according to the preferred embodiment of the present invention.
The multilayer body of this embodiment shown in FIG. 5 has a red light emitting film 6, a laser marking film 3, a blue light emitting film 7, a laser marking film 3 ′ and a green light emitting film 8 in that order. There is. The laser marking film 3 is the same as that shown in FIG. The laser marking film 3'has a higher concentration of the laser light energy absorber than the concentration of the laser light energy absorber contained in the laser marking film 3. The red light emitting film 6, the blue light emitting film 7, and the green light emitting film 8 emit light in red, blue, and green, respectively, upon irradiation with the first light (ray 1) and the second light (ray 2). It is a film containing the body. Before the laser marking process, the multilayer body of the present embodiment, by the irradiation of the first light, the red light emitting film 6 emits red light, the blue light emitting film 7 emits blue light, and the green light emitting film 8 emits green light. It glows and appears white.
On the other hand, in the first laser marking process, the concentration of the laser light energy absorber contained in the laser marking film 3 ′ is made higher than the concentration of the laser light energy absorber contained in the laser marking film 3, so that the laser Marking film 3'is selectively marked. In this case, since the laser marking film 3'is usually discolored to black, even if the first light is irradiated, the green light emitting film 8 below the light emission is weak, resulting in the black laser marking film 3 '. The red light emission and the blue light emission on the film are strongly detected. That is, the irradiation of the first light causes the treated multilayer body to have a slightly dark purple color.
Further, in the second laser marking process, laser marking is performed on both the laser marking film 3'and the laser marking film 3. In this case, since the laser marking film 3 is normally discolored to black, even if the second light is irradiated, the light emission of the blue light emitting film 7 and the green light emitting film 8 thereunder is weak, and as a result, The red emission on the black laser marking film 3 will be strongly detected. That is, the irradiation of the first light causes the treated multilayer body to have a slightly dark red color.

  On the other hand, by irradiation with the second light, in the multilayer body before the laser marking treatment, both films emit light in the same manner as when the first light is irradiated, and the same result is obtained. Even when the second light is irradiated, light is emitted as in the case of the first light irradiation, and the processed multilayer body exhibits a slightly dark red color.

FIG. 6 is a sectional view schematically showing another example of the multilayer body according to the preferred embodiment of the present invention.
The multilayer body of this embodiment shown in FIG. 6 has a red light emitting film 6, a laser marking film 3, and a blue green light emitting film 9 in that order. The red light emitting film 6 is the same as that shown in FIG. The laser marking film 3 is the same as that shown in FIG. The blue-green light-emitting film 9 is a light-emitting body that is a mixture of blue and green that emits blue-green light in response to the first light and the second light. Before the laser marking treatment, the multilayer body shown in FIG. 6 is irradiated with the first light, the red light emitting film 6 emits red light, the blue green light emitting film 9 emits blue green light, and the multilayer body is white. Looks like. On the other hand, after the laser marking process, the laser marking film 3 is normally discolored to black, so that even if the first light is irradiated, the light emission of the blue-green light emitting film 9 thereunder becomes weak. As a result, the red emission on the black laser marking film is strongly detected, giving a slightly darker red color.
On the other hand, by irradiation with the second light, in the multilayer body before the laser marking treatment, both films emit light in the same manner as when the first light is irradiated, and the same result is obtained. Even when the second light is irradiated, light is emitted as in the case of the first light irradiation, and the processed multilayer body exhibits a slightly dark red color.
In the embodiment of FIG. 6, by adjusting the laser marking conditions, the black optical density (OD value) of the laser marking portion may be adjusted to a predetermined value. By adopting this mode, it is possible to determine the authenticity only with the first light. Specifically, before the laser marking process, the red light emitting film 6 emits red light, the blue green light emitting film 9 emits blue green light, and the multilayer body looks white by the irradiation of the first light. On the other hand, after the laser marking processing, by adjusting the laser marking processing portion so as to have a certain OD value, even if the first light is irradiated, the light emitted from the blue-green light emitting film 9 therebelow is emitted. Is attenuated at a constant rate. As a result, a mixture of red emission on the black laser marking film and a slightly weaker blue-green light will be detected. By registering the red and blue-green lights at this time in advance, it is possible to determine the authenticity without irradiating the second light. In the embodiment of FIG. 6, when the black marking OD value of the laser marking processing portion is low, light red emission is exhibited, and as the OD value is increased, the visibility of red emission is increased.
Regarding the adjustment of the optical density, the embodiment of FIG. 6 is shown as an example, but it goes without saying that the multilayered body of other embodiments can also have the same configuration.

  FIG. 7 shows an embodiment in which the light shielding layer 31 is provided on the side of the multilayer body shown in FIG. The authenticity can be determined by irradiating the first light and the second light from the direction of the arrow in FIG. 7. By providing the light shielding layer, the contribution of light from the side opposite to the viewing direction is eliminated and the discoloration effect of the laser marking processing portion can be more easily viewed. Further, by laminating the multilayer body of the present invention on the printing surface of the adherend, it is possible to use it as a print protection film having an authenticity determining function. Here, the light shielding layer is not particularly limited as long as it is a layer that shields light, but usually, a resin film mixed with a white pigment or a black pigment is used. A chromatic pigment may be used as long as the luminescence used in the present invention can be confirmed.

  FIG. 8 shows a state in which a multilayer body corresponding to FIG. 3 is further provided on the surface of the light shielding layer 31 in the multilayer body shown in FIG. 7 on the opposite side of the multilayer body shown in FIG. is there. By adopting such a mode, two optical information, that is, the optical information after the laser marking processing by the multilayer body shown in FIG. 1 and the optical information after the laser marking processing by the multilayer body shown in FIG. 3 are combined into one multilayer body. Can be included. As a result, it is possible to obtain a more authentic anti-authentication film.

In the above-mentioned embodiments, the system for displaying the processing information after the laser marking processing is displayed on the entire surface of the multilayer body. However, depending on the application of the multilayer body, only a partial region in the surface direction of the multilayer body of the present invention may be used. You may provide the multilayer body of.
Further, a mode in which the multilayer body shown in FIG. 1 is incorporated into a part of the plane direction of the multilayer body and the multilayer body shown in FIG. 3 is incorporated into the other part is also exemplified as a preferable aspect of the present invention.

FIG. 9 is a sectional view schematically showing a multilayer body of a comparative example. The multilayer body of the comparative example shown in FIG. 9 has a blank film (resin film containing no light emitter) 4 and a yellow-green LM film 23 in that order. The yellow-green light emitting film 23 is the same as the example of FIG. In the multilayer body of this comparative example, the yellow-green light-emitting film 23 emits yellow-green light by being irradiated with the first light before the laser marking process. After the laser marking process, it usually looks black due to the irradiation of laser light.
On the other hand, when the light (second light) that the yellow-green light emitting body does not emit is irradiated, the yellow-green light emitting body does not emit light before the laser marking process. After the laser marking process, it usually looks black.
That is, the luminescent color seen after the laser marking process is the same whether the first light or the second light is irradiated.

FIG. 10 is a sectional view schematically showing a multilayer body of another comparative example. The multilayer body of the comparative example shown in FIG. 10 has a purple light emitting film 1 and a laser marking film 3 in that order. The purple light emitting film 1 is the same as the example of FIG. In the multilayer body of this comparative example, when the first light was not irradiated, the purple luminescent material did not emit light, and the color of the thermoplastic resin was directly visible. By irradiating this with the first light, the violet light-emitting film 1 emits violet light, and the multilayer body exhibits violet.
On the other hand, after the laser marking process, the laser marking film 3 turns black. When the first light is then irradiated, the purple light emitting film 1 emits purple light, and the multilayer body looks a little dark purple.
On the other hand, when the second light (light ray 2) is irradiated, the purple light-emitting film 1 does not emit light in the laser marking processing portion, so that the color of the thermoplastic resin (usually transparent) can be confirmed. On the other hand, the non-laser marking treated portion usually looks black.
That is, the luminescent color seen after the laser marking process is the same whether the first light or the second light is irradiated.

FIG. 11 is a sectional view schematically showing a multilayer body of another comparative example. The multilayer body of the comparative example shown in FIG. 11 has a blank film 4 (resin film containing no light emitter), a laser marking film 3, and a yellow-green light emitting film 2 in that order. The yellow-green light emitting film 2 is the same as the example of FIG. In the multilayer body of the comparative example shown in FIG. 11, when the first light is not irradiated, the color of the thermoplastic resin as it is can be confirmed. On the other hand, by irradiating the first light, the yellow-green light emitting film 2 emits yellow-green light. After the laser marking process, the laser marking film 3 turns black. Even if the first light is irradiated thereafter, the emission intensity of yellow-green of the yellow-green light-emitting film 2 becomes weak and remains black.
On the other hand, when the second light (light ray 2) is irradiated, the yellow-green light emitting film 2 does not emit light in the laser marking processing portion, so that the color of the thermoplastic resin as it is (usually transparent) can be confirmed. On the other hand, the non-laser marking treated portion usually looks black.
That is, the luminescent color seen after the laser marking process is the same whether the first light or the second light is irradiated.

FIG. 12 is a sectional view schematically showing a multilayer body of another comparative example. The multilayer body of the comparative example shown in FIG. 12 has a purple light emitting film 1, a blank film 4, and a yellowish green light emitting film 2 in that order. The purple light emitting film 1 and the yellow green light emitting film 2 are the same as the example of FIG. In the multilayer body of the comparative example shown in FIG. 12, the color of the thermoplastic resin as it is (usually transparent) can be confirmed when the first light is not irradiated. By irradiating this with the first light, the purple light emitting film 1 emits purple light, the yellow green light emitting film 2 emits yellow green light, and the multilayer body exhibits white. Further, even after the laser marking treatment, there is no discoloration due to the laser marking treatment, and there is no change.
In contrast, the untreated multilayer and the treated multilayer do not respond to the second light, and the color (usually transparent) of the thermoplastic resin as it is can be confirmed.
That is, the luminescent color seen after the laser marking process is the same whether the first light or the second light is irradiated.

FIG. 13 is a sectional view schematically showing a multilayer body 5C of another comparative example. The multilayer body of Comparative Example has a purple light emitting film 1, a laser marking film 3, and a blank film 4 in that order. The purple light emitting film 1 is the same as the example of FIG. In the multilayer body of the comparative example shown in FIG. 13, the color of the thermoplastic resin as it is can be confirmed when the first light is not irradiated. By irradiating this with the first light, the violet light-emitting film 1 emits violet light, and the multilayer body exhibits violet. When this is subjected to a laser marking process, the laser marking film 3 turns black. Then, when the first light is irradiated, the purple light emitting film 1 emits purple light, and the multilayer body becomes slightly dark purple.
On the other hand, the untreated multilayer body does not respond to the second light, and the color (usually transparent) of the thermoplastic resin can be confirmed as it is, and the treated multilayer body becomes black.
That is, the luminescent color seen after the laser marking process is the same whether the first light or the second light is irradiated.

FIG. 14 is a sectional view schematically showing a multilayer body of another comparative example.
The multilayer body of the comparative example shown in FIG. 14 is a yellow-green light emitting film 2 which emits yellow-green light in response to a first light (light ray 1), a laser marking film 3 including a laser light energy absorber, and an orange. And an orange dye film 5 colored with the above dye in this order. The aspect of the yellow-green light emitting film 2 is the same as that of FIG. The laser marking film 3 is the same as the embodiment shown in FIG. The orange dye film 5 is not responsive to ultraviolet light and exhibits absorption of orange light in the visible light region.
In the multilayer body of the present embodiment, before the laser marking process, the yellow-green light-emitting film 2 emits light by irradiation of the first light, and yellow-green light is observed, but the coloring effect of the orange film 5 that does not emit light is It looks yellowish green because it is weak. On the other hand, after the laser marking treatment, the laser marking film 3 is usually discolored to black, so that even if the first light is irradiated, the orange coloring effect of the orange dye film 5 thereunder can be obtained. I can't. As a result, only the yellow-green emission of the yellow-green emitting film on the black laser marking film will be detected. That is, in the same manner as in the embodiment shown in FIG. 1, the treated multilayer body exhibits a slightly dark yellowish green color by the irradiation of the first light.
On the other hand, when the second light is irradiated, the laser marking non-processed part exhibits the same color as the thermoplastic resin (orange in this example), and when the second light is irradiated, the laser marking processed part is usually It looks black. Therefore, the authenticity cannot be determined even if the additional laser marking process is performed.
That is, the luminescent color seen after the laser marking process is the same whether the first light or the second light is irradiated.

FIG. 15 is a sectional view schematically showing a multilayer body of another comparative example.
The multilayer body of the comparative example shown in FIG. 15 comprises an orange dye film 5 colored with an orange dye, a laser marking film 3 containing a laser light energy absorber, and a yellow dye in response to a first light (ray 1). It has a yellowish green light emitting film 2 which emits green light in this order. The orange dye film 5 is the same as in FIG. The laser marking film 3 is the same as the embodiment shown in FIG. The aspect of the yellow-green light emitting film 2 is the same as that of FIG.
In the multilayer body of this embodiment, yellow laser light emission of the yellow-green light emitting film 2 due to the irradiation of the first light is confirmed before the laser marking process, but the coloring effect of the orange dye film 5 as the lower layer is weak. Therefore, it looks yellowish green. At this time, the orange dye film 5 is translucent, and the yellow-green light emission of the yellow-green light emitting film 2 therebelow can be visually recognized or detected through the orange dye film 5. After the laser marking process, since the laser marking film 3 is normally discolored to black, even if the first light is irradiated, the yellow-green light emitting film 2 thereunder does not emit light, and only the black color is emitted. appear. On the other hand, when the yellow-green luminescent material and the orange dye do not emit light (second light), the non-laser marking processing part shows the same color as the thermoplastic resin (orange in this example), and the laser marking processing is performed. The part usually looks black. That is, even if the laser marking processing unit irradiates the light beam 1, the laser marking processing unit irradiates the light beam 2 and looks black.
That is, the luminescent color seen after the laser marking process is the same whether the first light or the second light is irradiated.

The multilayer body of the present invention may have a printed layer. The print layer is also called a design layer. As a method for forming a printing layer, a desired design is directly printed on the multilayer body by gravure printing, flexographic printing, etc., and is formed by heating and drying. It is formed by printing on a transfer sheet such as a biaxially stretched PET film. Examples of the method include transferring the printed layer to a multilayer body by a method such as heat transfer.
The printing layer can be printed using, for example, a polyester-based, polycarbonate-based, acrylic-based, or urethane-based printing ink, and particularly when there is a problem with the adhesion to the hard coat layer, plasma, ion etching, corona discharge It is also possible to improve the adhesion by surface-modifying by surface treatment such as. In addition, a method of forming a printed layer by providing a metal layer, a metal oxide layer, or the like on the thermoformed sheet by using a physical vapor deposition method or a chemical vapor deposition method can also be mentioned. The printed layer can be incorporated within the scope of the present invention. For example, the printed layer is provided as in the resin layer (A) / printed layer / resin layer (B) configuration, and the printed portion is the resin (B). It is also possible to make a multilayer body in which the contribution of light emission due to the above is weakened and the influence (light emission) of the resin layer (A) is visually recognized.
The multilayer body of the present invention is not limited to the one shown in the above drawings, and the laminated constitution of the film can be set by appropriately changing or applying it without departing from the gist of the present invention.

<Resin composition>
To the multilayer body of the present invention, a resin or resin composition that is commonly used as long as the effects of the present invention are exhibited can be applied. For the resin layer (A), the resin layer (B) and the resin layer (C), it is preferable to use a resin composition suitable for constituting the layers and preferably keeping the shape as a film.

<< resin >>
Examples of the resin contained in the resin composition include an ultraviolet curable resin, a thermosetting resin, an adhesive resin, an adhesive resin, an ink binder resin, and a thermoplastic resin, but among them, a thermoplastic resin. Is preferable from the viewpoint of molding. Among them, it is preferable to contain at least one kind of polycarbonate resin and polyester resin, more preferable to contain at least one kind of polycarbonate resin and amorphous polyester resin, and it is further preferable to contain at least one kind of polycarbonate resin.

A polycarbonate resin is a-[O-R-OCO]-unit (R is an aliphatic group, an aromatic group, or a group containing both an aliphatic group and an aromatic group) containing a carbonic acid ester bond in the molecular main chain. And the aliphatic group may have a linear structure or a branched structure). In the present invention, it is particularly preferable that each film contains an aromatic polycarbonate resin.
The weight average molecular weight of the polycarbonate resin is preferably 20,000 to 80,000, more preferably 21,000 to 50,000, and even more preferably 22,000 to 40,000.
The glass transition temperature of the polycarbonate resin is preferably 120 ° C. or higher, and more preferably 130 ° C. or higher. The upper limit is preferably 160 ° C. or lower, more preferably 155 ° C. or lower.

The polyester resin may be an amorphous polyester resin or a crystalline polyester resin.
Examples of the amorphous polyester resin include PETG resin and PCTG resin.
PETG resin is a polyester copolymer composed of a dicarboxylic acid unit mainly containing terephthalic acid units, an ethylene glycol unit, and a glycol unit mainly containing 1,4-cyclohexanedimethanol units, and 1,4-cyclohexanedimethanol units are , Occupy less than 50% of all glycol units on a molar basis. The terephthalic acid unit preferably accounts for all dicarboxylic acid units.
The PCTG resin is a polyester copolymer composed of a dicarboxylic acid unit mainly containing terephthalic acid units, an ethylene glycol unit, and a glycol unit mainly containing 1,4-cyclohexanedimethanol units, and is 1,4-cyclohexanedimethanol. The units account for 50% or more of all glycol units on a molar basis. The terephthalic acid unit preferably accounts for all dicarboxylic acid units.

  Examples of the crystalline polyester resin include polycaprolactone.

  In the thermoplastic resin, a combination of a polycarbonate resin and a polyester resin, a combination of a polycarbonate resin or a polyester resin and another thermoplastic resin, or a combination of a polycarbonate resin, a polyester resin and another thermoplastic resin Good. In the present invention, the polycarbonate resin or the polyester resin (preferably polycarbonate resin) preferably accounts for 50% by mass or more of the entire thermoplastic resin, more preferably 60% by mass or more, and 80% by mass or more. Is more preferable. The upper limit is not particularly limited, and the polycarbonate resin or the polyester resin may be 100% by mass. As the polycarbonate resin, one kind or a plurality of kinds may be used. Regarding the polyester resin, one kind or a plurality of kinds may be used. When a plurality of materials are used in each case, the total amount is within the above range.

<Light emitter>
In the multilayer body of the present invention, the resin layer (A) constituting the multilayer body contains the first luminous body, and the luminous body is provided with energy (for example, irradiation with ultraviolet light, visible light, infrared rays). It is preferably a light-emitting body that receives and emits light. Further, in the multilayer body of the present invention, the resin layer (B) or the resin layer (C) can contain the second luminescent material. Furthermore, the resin layer (B) and the resin layer (C) may include a third light emitter and a fourth light emitter. The third and subsequent light emitters may further include one resin layer (A), one resin layer (B) and one resin layer (C) as the second and subsequent light emitters, or the resin layer. At least one of (A), the resin layer (B) and the resin layer (C) may be two or more layers.
When the multilayer body of the present invention includes both the resin layer (B) and the resin layer (C), the luminous body contained in the resin layer (B) and the luminous body contained in the resin layer (C) are usually different. It is a kind of light emitter.

  The preferred compounds employed as the first luminescent material and the second luminescent material are as described above, but the first luminescent material and the second luminescent material are different compounds.

A luminescent material is a material that emits light when energy is applied.
The first light emitter and the second light emitter preferably emit light by irradiation with electromagnetic waves, and may emit light by radio waves, microwaves, far infrared rays, infrared rays, ultraviolet rays, far ultraviolet rays, X-rays, and γ rays. It is more preferable to emit light by ultraviolet light or infrared light. In this way, by emitting light with electromagnetic waves other than visible light, it is possible to prevent information diffusion and easy forgery without visually recognizing the color state of the multilayer body.
Examples of the short wavelength light include light having a wavelength of 200 to 450 nm, and short wavelength light of 250 to 420 nm is more preferable.
Examples of long-wavelength light include light having a wavelength of 800 to 10,000 nm, and light having a wavelength of 900 to 1500 nm is more preferable.
Further, it is preferable that the first light emitter and the second light emitter are light emitters excited by light supplied from the same light source. The first light emitter and the second light emitter may be excited by light having the same wavelength and emitted from the same light source, or may be excited by light having different wavelengths emitted from the same light source. Preferably, the difference between the maximum excitation wavelengths of the first luminescent material and the second luminescent material is preferably within 50 nm, more preferably within 10 nm. The maximum excitation wavelength is the wavelength at which the luminescent material is most excited.

  As the first luminous body and the second luminous body, B, F, Mg, Al, Si, P, S, Cl, Ca, V, Mn, Cu, Zn, Ge, Sr, Y and Ba are independently formed. , La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and a compound containing an element selected from the group consisting of Lu. Examples of the compound forming the light emitting body include a composite oxide of these elements and oxygen atoms, an organometallic compound in combination with an organic group, and the like.

  As the luminous body, it is preferable to use a luminous body that emits infrared light or ultraviolet light, and it is more preferable to use a luminous body that emits ultraviolet light. Examples of the luminescent material that emits ultraviolet light include those that are excited by ultraviolet light and have a spectrum peak emitted in the wavelength range of blue, green, red, or the like. Specifically, a small amount of a metal (copper, silver, manganese, bismuth, lead, etc.) is added as an activator to a high-purity luminescent material such as zinc sulfide or an alkaline earth metal sulfide in order to enhance the emission. The thing obtained by baking at high temperature is mentioned. The luminous body that emits ultraviolet light can be adjusted in hue, brightness, and degree of color attenuation by a combination of a host crystal and an activator.

  Examples of the compound that can be used as a light-emitting body in the present invention include, for example, paragraphs 0019 and 0090 to 0097 in JP-A-2015-168728, and paragraphs 0033, 0034, and 0069 in JP-A-10-129107. Reference may be made to these disclosures, which are incorporated herein.

The first luminescent material and the second luminescent material are each preferably contained in the resin composition in an amount of 0.01 mass% or more, more preferably 0.05 mass% or more, and 0.1. More preferably, it is at least 07% by mass. The upper limit is preferably 5.0% by mass or less, more preferably 2.0% by mass or less, and further preferably 1.0% by mass or less. When the content ratio of the luminescent material is not less than the lower limit value, detection with a detector becomes easier. When the content ratio of the luminescent material is not more than the upper limit value, the luminescent color becomes clearer, which is preferable.
As described above, one type of luminescent material may be used in one type of resin composition, or two or more types may be used. When two or more kinds are used, the total amount is preferably within the above range.

<Laser light energy absorber>
In the multilayer body of the present invention, the resin layer (B) contains a laser light energy absorber. A laser marking agent can be used for the laser light energy absorber.
The laser light energy absorber (laser marking agent) can change the color of the thermoplastic resin. It usually turns black. From this viewpoint, the wavelength of the laser beam is preferably 700 nm or more, more preferably 800 nm or more, and further preferably 900 nm or more. As an upper limit, 1200 nm or less is practical.
The laser light energy absorber preferably has a maximum absorption wavelength at a wavelength different from the maximum excitation wavelength of the above-mentioned luminescent material. More specifically, the difference between the maximum excitation wavelength of the light-emitting body and the maximum absorption wavelength of the laser light energy absorber is preferably 50 nm or more, more preferably 100 nm or more, and 200 nm or more. Is more preferable. The upper limit of the difference between the maximum excitation wavelength of the light emitting body and the maximum absorption wavelength of the laser light energy absorbing body is not particularly limited, but is usually 1000 nm or less.

  Examples of the laser light energy absorber include at least one selected from the group consisting of carbon black, titanium black, metal oxides, metal sulfides, and metal nitrides. Of these, one or more selected from the group consisting of carbon black, titanium black, and metal oxides are preferable.

  Here, when the laser light energy absorber is carbon black, the average particle size is preferably 150 nm or less, more preferably 100 nm or less, and further preferably 90 nm or less. It is practical that the lower limit value is 10 nm or more. Further, the laser light energy absorber is preferably carbon black having a dibutyl phthalate (DBT) oil absorption of 60 to 170 mL / 100 gr. It is preferable that the average particle diameter is not more than the above upper limit value because the laser coloring property can be maintained high. When the average particle diameter is not less than the above lower limit value, it is possible to suppress coloring of the film, which is preferable. Further, when the DBT oil absorption is not less than the above lower limit, dispersibility can be maintained.

Titanium black and metal oxides having an average particle size of 10 μm or less are preferable because the laser coloring property and the printing clarity can be maintained. Examples of the metal forming the oxide include zinc, magnesium, aluminum, iron, titanium, silicon, antimony, tin, copper, manganese, cobalt, bismuth, vanadium, niobium, molybdenum, ruthenium, tungsten, palladium, silver, platinum and the like. Be done. Furthermore, ITO, ATO, AZO etc. are mentioned as a complex metal oxide.
Examples of the metal sulfide include zinc sulfide and cadmium sulfide. Furthermore, examples of the metal nitride include titanium nitride.

The content of the laser light energy absorber in the resin composition is preferably 0.0005 parts by mass or more, and 0.001 parts by mass or more with respect to 100 parts by mass of the resin. It is more preferable that the amount is 0.005 parts by mass or more. The upper limit is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and further preferably 1 part by mass or less.
The laser light energy absorber may be used alone or in combination of two or more. When two or more kinds are used, the total amount is preferably within the above range.

In the present invention, it is preferable that in the multilayer body, the resin layer (B) containing the laser light energy absorber is effectively discolored by irradiation with a laser beam. As the laser light, He-Ne laser (wavelength 633 nm), Ar laser, CO ₂ laser (wavelength: 9.3 μm to 10.6 μm), gas laser such as excimer laser (ArF excimer laser (wavelength 193 nm), KrF excimer laser) (Wavelength 248 nm), XeCl excimer laser (wavelength 308 nm), XeF excimer laser (wavelength 351 nm)), YAG laser (wavelength 1064 nm), solid-state laser such as Nd / YVO ₄ laser (wavelength 1065 nm), semiconductor laser, dye laser, etc. Can be mentioned. Of these, YAG laser and Nd.YVO ₄ laser are preferable.

<Other ingredients>
The resin composition constituting the film may contain additives such as an antioxidant, a heat stabilizer, a flame retardant, a flame retardant aid, and a release agent, in addition to the above components. Alternatively, as long as the effect of the present invention is not impaired, it contains additives such as an ultraviolet light absorber, an antistatic agent, an optical brightening agent, an antifogging agent, a fluidity improving agent, a plasticizer, a dispersant, and an antibacterial agent. Good. The content of the additive as described above in the thermoplastic resin is preferably 1.0% by mass or less, more preferably 0.5% by mass or less, based on the mass of the entire thermoplastic resin. It is more preferably 0.1% by mass or less.

<Film forming>
The method for molding the multilayer body of the present invention is not particularly limited, and an ordinary method can be appropriately used.
For example, there is exemplified a mode in which the thermoplastic resin composition forming each layer of the multilayer body is formed into a film shape by extrusion molding or the like, and the film corresponding to each obtained layer is hot pressed.
Further, the thermoplastic resin composition forming each layer of the multilayer body can be coextrusion-molded.

<Authenticity judgment method>
The multilayer body of the present invention can be suitably used for an authenticity judging method using the same. The authenticity determining method according to a preferred embodiment of the present invention will be described. After performing the laser marking treatment on the resin layer (B) of the above-mentioned multilayer body, the resin layer (A) side or the opposite side, Examples include a method including irradiating light capable of emitting light from each of the one light emitter and the second light emitter. In the present invention, light irradiation is preferably performed from the resin layer (A) side. Here, the light capable of causing the first light-emitting body and the second light-emitting body to emit light is a wavelength within the maximum excitation wavelength ± 50 nm for the first light-emitting body and the second light-emitting body, respectively. Is preferably irradiated with light having a wavelength within the maximum excitation wavelength of ± 30 nm, more preferably irradiation with light having a wavelength within the maximum excitation wavelength of ± 10 nm, and further preferably irradiated with light having a maximum excitation wavelength of ± 5 nm. It is more preferable to irradiate light having a wavelength within the range. In the present invention, the light emitted from this multilayer body is further detected. The detection here may be carried out mechanically by a sensor or the like, but it means that a person visually confirms it. Then, when the light detected above is the true light of the multilayer body, that is, when the specific light is irradiated as the multilayer body after the laser marking treatment, the resin layer (A) and the resin layer (B) are required. Then, it is determined whether or not the light is assumed to be emitted from the resin layer (C). If this is true light, the multi-layer body tested for authenticity is determined to be genuine (Yes in FIG. 16), and otherwise it is determined to be counterfeit (No in FIG. 16). For the above determination, it is preferable to use a true light emission database (true light emission DB) in which true light emission is recorded and stored (FIG. 17).
In one embodiment of the present invention, the specific light is preferably ultraviolet light, and the wavelength of light is preferably in the range of 200 to 450 nm.
As another embodiment, the specific light is preferably infrared light, and the wavelength of the light is preferably in the range of 800 to 10,000 nm. The above-mentioned another embodiment is, for example, a light emitter 1 (manufactured by Nemoto Special Chemical Co., product number D20001, excitation wavelength 825 nm, emission wavelength 965 nm), a light emitter 2 (manufactured by Nemoto Special Chemical Co., product number ASG, excitation wavelength 950 nm, emission wavelength 670 nm) can be used.
A security card is preferable as the multilayer body applied to the authenticity determining method of the present embodiment.

<Authenticity judgment system>
FIG. 18 is a device configuration diagram showing an example of the authenticity determination system according to the preferred embodiment of the present invention. In the present embodiment, the multilayer body 10 is irradiated with the specific light C1 from the light source 51. The preferable range of this specific light is the same as the authenticity determination method described above. In the authenticity determination system of the present embodiment, the multilayer body after the laser marking process is irradiated with the specific light to cause the multilayer body to emit light, and the light emission C2 is detected by the detection unit 52. The light source (light irradiation unit) 51 and the detection unit 52 are connected to a computer 53 and operated under the control of the computer 53. Next, the computer 53 determines whether the light emitted by the multilayer body is the authentic light emitted by the multilayer body after the laser marking process is performed. The procedure of this determination is the same as the flowchart (FIGS. 16 and 17) shown in the authenticity determination method. However, in the authenticity determination system of the present embodiment, the detection is not performed by the human eye, but is performed by the detection unit. There are various determination methods, and a method for determining by comparing the true light emission database (DB) described below with the detected light can be given.
Further, the system according to the present embodiment includes an image display unit 54 that displays the determination result, a printing unit 55 that can print the determination result and its analysis result, and a medium recording unit that records the determination result in a recording medium. The system is connected to 56 and the like and is entirely controlled by a computer. Examples of the recording medium include a magnetic tape, a magnetic disk, an optical disk, and a semiconductor memory.

<Authenticity judgment program>
A program written in a computer-readable format according to a preferred embodiment of the present invention is programmed so as to sequentially advance the procedure shown in the flowchart of FIG. Specifically, it is a program written in a computer-readable format, the step of detecting light emitted by the multilayer body of the present invention, and laser marking in which the light emitted by the multilayer body is registered in advance. A program for causing a computer to execute a process including an authenticity determination step of determining that the light emitted by the multilayer body is authentic light when the multilayer body after the process has performed matches the emitted light. Has become. The light emitted by the multilayer body after the pre-registered laser marking treatment is a combination of the light emitted by the laser marking non-treatment portion and the light emitted by the laser marking treatment portion, or the laser marking non-treatment portion. Examples include the case where the light emitted from the processing unit is the light emitted from the laser marking processing unit having a blackness of a specific optical density.
Further, the embodiment will be described with reference to FIG. 16 in a series of steps. When the program is started, the laser marking processing of the multilayer body is executed. However, the laser marking process may not be performed within this program, but the pretreatment of the test body may be performed, and thus the multilayer body subjected to the laser marking process may be supplied separately. In a preferred embodiment of this program, specific light is irradiated from the resin layer (A) side of the multilayer body. The specific light is as defined above, preferably ultraviolet light or infrared light. Then, the light emission from the laser-marked multilayer body is detected. The detection at this time may be visually confirmed, and the result may be input and sent to the computer, but it is preferable that the detection is performed by a detection unit connected to the computer. Then, it is determined whether the detected light is the true light of the multilayer body. If it is judged to be authentic (Yes in FIG. 16), the tested multilayer body is judged to be authentic. Otherwise (No in FIG. 16), it is determined to be forgery.

  In a preferred embodiment of the program of the present invention, in the authenticity determining step, the detected light from the multilayer body is compared with a true light emission database (true light emission DB) that stores a large amount of information of true light emission, and the corresponding light emission is performed. If the information is present in the database, it is determined to be authentic, and if it is not present, it is determined to be forged (inauthentic). At this time, the true light emission database may be recorded and stored as a data structure in this program, but it is also preferable to keep it in a different place from this program such as a server or a cloud service platform in another form.

<Use>
The multilayer body of the present invention is preferably used as a security card such as an ID card, an e-passport, and a non-contact type IC card. However, its use is not limited, and it can be widely used in fields where it is desired to prevent counterfeiting, such as product tags, distribution information, personal data management, and crime prevention systems.

  Hereinafter, the present invention will be described more specifically with reference to Examples. However, the present invention is not limited to the following examples, and can be implemented by being arbitrarily modified without departing from the spirit of the present invention.

<Production of film>
Sheets of test pieces were manufactured as follows using the resin compositions having the compositions shown in Table 1 and Table 2.
Using a T-die melt extruder consisting of a twin-screw extruder having a barrel diameter of 32 mm and a screw L / D = 31.5, a mirror-finished sheet having a width of 300 mm and a discharge rate of 20 kg / h and a screw rotation speed of 200 rpm was formed. At a cylinder / die head temperature of 280 ° C., a film having a thickness of 300 μm (0.3 mm) was formed for each resin composition.

<< raw material >>
Polycarbonate resin: Mitsubishi Gas Chemical Co., E-2000F
Violet luminescent material: Manufacturer: Nemoto Special Chemical Co., Ltd., product number: V-300M, Red light emitting material that emits light in response to light ray 1 (light having a wavelength of 365 nm): Manufacturer: Nemoto Special Chemical Co., product number: D1124, light ray 1 A yellow-green luminescent material that emits light in response to both (light having a wavelength of 365 nm) and light ray 2 (light having a wavelength of 254 nm): Manufacturer: Nemoto Special Chemical Co., Ltd., Part number: G-300FF, Light emission in response to light ray 1 Blue light emitter: Manufacturer: Nemoto Special Chemical Co., Ltd., product number: D1184T, green light emitter that emits light in response to both light ray 1 and light ray 2: Manufacturer: Nemoto Special Chemical Co., product number: D1164, light ray 1 and light ray 2 Orange dye that emits light in response to both: Manufacturer: LANXESS Corporation, Product number: Orange 3G
Laser marking agent (LM agent, laser light energy absorber): carbon black, manufacturer: Cabot Japan KK, product number: MONARCH 800

In the above table, the unit of each component is mass ratio.

<Evaluation>
Preparation of Test Pieces The films obtained above were stacked so as to have a layer structure shown in Table 3 or Table 4 described later, and sandwiched between auxiliary plates for pressing. The pressing auxiliary plate is composed of four sheets of a 0.5 mm SUS plate, a 1 mm silicon rubber sheet, a 100 μm SUS plate, and a 0.78 mm Teflon (registered trademark) sheet in this order. The stacked films were sandwiched so that the Teflon sheet was on the inside. While sandwiched between the auxiliary press plates, the stacked films were sandwiched between a pair of press plates of the press machine so that the 0.5 mm SUS plate was on the outside, and a pneumatic heating press (IMC-1839 type: manufactured by Imoto Machinery Co., Ltd.) Was used for 180 seconds at 180 ° C. and an air pressure of 0.2 MPa to produce a multilayer body.

<Laser marking processing>
Using a laser marking device (“EasyMark IV-E10” manufactured by Roffin Basel), laser marking was performed on the multilayer body obtained by pressing under the following irradiation conditions.
The laser focused on the layer containing the laser marking agent.

Laser marking conditions Wavelength: 1064nm (YAG laser)
Scan Speed: 1,000 mm / s ⁻
Output Energy: 21-30A
Pulse Frequency: 10 to 100 kHz

<Evaluation>
The laser-marked multilayer body is irradiated with light 1 (light ray 1, light with wavelength 365 nm) and light 2 (light ray 2, light with wavelength 254 nm) to reduce the difference in color between the laser marking treated portion and the non-treated portion. It was visually observed in a dark room.
The results are shown in Tables 3 and 4. The stacking order of the films of Examples and Comparative Examples is shown in FIGS.

  As is clear from the above results, the authenticity of the multilayer body can be determined by using the multilayer body of the present invention.

<Example 6>
In Example 6, a multilayer body having the layer structure shown in FIG. 6 was manufactured. In FIG. 6, 6 is a red light emitting film, 3 is a laser marking film, and 9 is a blue green light emitting film. The concentration of the laser marking agent in the laser marking film 3 was adjusted to the optical density shown in Table 5, and three multilayer bodies were manufactured. Others were the same as in Example 1.
The OD value (optical density) is calculated by -Log ₁₀ (transmitted light / incident light) and used as an index of blackness. The laser marking treated portion and the laser marking non-treated portion were compared in color, and the difference was visually observed. The lower the OD value of the laser marking treated portion, the lighter the red color of the laser marking treated portion, and the higher the OD value of the laser marking treated portion, the deeper the red color of the laser marking treated portion.

1 Purple Light Emitting Film 2 Yellow Green Light Emitting Film 3, 3'Laser Marking Film 4 Blank Film 5 Orange Dye Film 6 Red Light Emitting Film 7 Blue Light Emitting Film 8 Green Light Emitting Film 9 Blue Green Emitting Film 10 Multilayer 11 Yellow Green Emitting Element ( A film (yellow-green / red film) containing a ray 1) and a red light emitter (ray 1, ray 2)
21 A film (purple / blue-green film) containing a purple light emitter (ray 1) and a blue-green light emitter (ray 2)
23 Film containing laser marking agent and yellow-green luminescent material (yellow-green LM film)
30 laser irradiation unit 31 light shielding layer 51 light source 52 detection unit 53 computer 54 image display unit 55 printing unit 56 medium recording unit C1 irradiation light C2 emission color

Claims (22)

A resin layer (A) containing a first luminous body, and a resin layer (B) containing a laser light energy absorber,
Furthermore, a multilayer body satisfying at least one of the following (1) and (2):
(1) The resin layer (B) contains a second luminous body different from the first luminous body;
(2) Further, a resin layer (C) is provided, the resin layer (C) is located on the opposite side of the resin layer (B) from the resin layer (A), and the first light emitting body is provided. Contains a different second illuminant.   The multilayer body according to claim 1, which satisfies the above (1).   The multilayer body according to claim 1 or 2, which satisfies the condition (2).   The multilayer body according to any one of claims 1 to 3, wherein the second luminous body is at least one kind selected from luminous bodies excited by at least one of ultraviolet light and infrared light.   5. The first luminous body and the second luminous body are at least one kind selected from luminous bodies excited by light supplied from the same light source, according to claim 1. Multi-layered body.   The multilayer body according to claim 1, wherein the first luminescent material is at least one selected from luminescent materials that are excited by at least one of ultraviolet light and infrared light.   The multilayer body according to any one of claims 1 to 6, wherein the resin layer (A) contains at least one of a polycarbonate resin and a polyester resin.   The multilayer body according to any one of claims 1 to 7, wherein at least one of the resin layer (B) and the resin layer (C) contains at least one kind of a polycarbonate resin and an amorphous polyester resin.   The first luminous body is B, F, Mg, Al, Si, P, S, Cl, Ca, V, Mn, Cu, Zn, Ge, Sr, Y, Ba, La, Ce, Pr, Nd, The multilayer body according to any one of claims 1 to 8, comprising an element selected from the group consisting of Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.   The second luminous body is B, F, Mg, Al, Si, P, S, Cl, Ca, V, Mn, Cu, Zn, Ge, Sr, Y, Ba, La, Ce, Pr, Nd, The multilayer body according to any one of claims 1 to 9, comprising an element selected from the group consisting of Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.   The multilayer body according to any one of claims 1 to 10, which is used for determining authenticity.   The multilayer body according to any one of claims 1 to 11, which is a security card.   The multilayer body according to any one of claims 1 to 12, wherein the resin layer (B) is subjected to laser marking treatment.   Furthermore, the multilayer body according to any one of claims 1 to 13, which has a light shielding layer.   The multilayer body according to claim 14, wherein the light shielding layer contains a white pigment or a black pigment.   A specific structure capable of emitting light from each of the first light emitter and the second light emitter after performing the laser marking treatment on the resin layer (B) of the multilayer body according to any one of claims 1 to 15. Of authenticating a multi-layered body, including irradiating the same with light.   The authenticity determination method according to claim 16, wherein the wavelength of the specific light is in the range of 200 to 450 nm.   The authenticity determination method according to claim 16, wherein the wavelength of the specific light is in the range of 800 to 10,000 nm.   The authenticity determination method according to claim 16, wherein the multilayer body is a security card. The multilayer body according to any one of claims 1 to 15, wherein the multilayer body after the laser marking process is irradiated with specific light to cause the multilayer body to emit light,
The light emitted by the multilayer body when the light emitted by the multilayer body after the laser marking processing matches the light emitted by the multilayer body after the pre-registered laser marking processing. An authenticity determination system having an authenticity determination unit that determines that the light is genuine light.   The light emitted by the multilayer body after the pre-registered laser marking processing is performed includes light emitted by the laser marking non-treatment portion and light emitted by the laser marking treatment portion having a specific optical density. The authenticity determination system according to claim 20. A program written in a computer-readable format,
Detecting the light emitted by the multilayer body according to any one of claims 1 to 15,
When the light emitted by the multilayer body matches the light emitted by the multilayer body after the pre-registered laser marking process is performed, it is determined that the light emitted by the multilayer body is authentic light. A program for causing a computer to execute processing including an authenticity determination step.