JP5948732B2 - Anti-counterfeit media - Google Patents

Description

  The present invention relates to an anti-counterfeit medium that can be suitably used for securities such as banknotes or certificates such as official documents.

  Conventionally, in order to prove that a security or a certificate is genuine, that is, to prevent counterfeiting, optically variable technologies such as holograms and diffraction gratings, security stripes or strips, microprints, fine lines or “ Other optically modified inks such as “watermark” patterns, moire-inducing patterns, fluorescent inks, phosphorescent inks, nacreous inks or metameric inks have been used as anti-counterfeit structures.

On the other hand, Patent Document 1 introduces a technique for forming a transparent window in a part of a certificate by providing an opening in the certificate and covering the opening with a film.
In addition to requiring special processing of the transparent window itself in the securities, if this window has sufficient transparency, by installing the aforementioned anti-counterfeit structure on the window, It becomes possible to confirm the effect of the forgery prevention structure from the front and back.

Since authenticity can be verified from either the front or back side, it is easy to verify the authenticity, contributing to the effect of preventing forgery.
Furthermore, in recent years, a new anti-counterfeit technology using a transparent window of securities has been proposed. For example, in Patent Document 2, by folding the base material of the securities, the “transparent window region” in the securities and the “anti-counterfeit structure region” separately installed in the securities are overlapped, The self-proof is made possible by obtaining a new effect.

  Specific examples of the combination of “transparent window region” and “counterfeit prevention structure region” in Patent Document 2 include a combination of a transparent window and a microprint of a microlens array, a combination of a colored transparent window and a metameric ink, A combination of polarized transparent windows and a combination of moire inducing patterns are mentioned. According to the combination of these “transparent window region” and “counterfeit prevention structure region”, self-proof is possible by superimposing these regions.

JP-T 9-503711 JP 2000-505738

  However, there is a problem that printing such as microprints and moire-induced patterns is highly likely to be imitated by a commercially available printer. On the other hand, the metameric ink needs to use a special pigment, and the transparent polarizing window needs to be made by aligning a special dye. Since these special materials are expensive, there is a problem that the area to be used is small, and it is difficult to understand when determining authenticity.

  Therefore, the present invention has been made in view of such circumstances, and an object thereof is to provide a forgery prevention medium which is difficult to forge and can be manufactured at a relatively low cost even in a large area.

[Invention 1] forgery prevention medium according to one aspect of the present invention, the film-like substrate, a counterfeit prevention medium comprising a first region, a second region and a verification region includes a third area, the The first region has a transparent window including a scattering element, and at least one of the second region and the third region has a concavo-convex reflective layer, and the surface of the substrate is The color difference between the second region and the third region measured when observed from the vertical direction is ΔE1, and the surface of the substrate is passed over the first region under the same measurement conditions as when the ΔE1 is measured. when the color difference of the second region to be measured and the third area are .DELTA.E2 when observed in the said .DELTA.E1 .DELTA.E2, due Succoth satisfy either formula 1 or formula 2 below, the When the first area and the verification area do not overlap, the second area and the first area Distinguished by visual observation and region Tsukazu, the first region and said verification region is in a state of overlapping in a plan view, wherein the third region appears.
Formula 1 ... | ΔE1−ΔE2 |> ΔE1 (where ΔE2> ΔE1)
Expression 2 ... | ΔE1−ΔE2 |> ΔE2 (where ΔE1> ΔE2)

[Invention 2] The medium for preventing forgery according to another aspect of the present invention, the first region has a transparent window including a scattering element, wherein the second region and the third region, the aspect ratio of the recess or to each other Regular reflection of the visible light in the second region and the third region, each having a reflective layer having a concavo-convex structure with different densities, and measured when the surface of the substrate is irradiated with visible light from a predetermined angle Let Δr1 be the difference in rate, and the difference in regular reflectance of the visible light between the second region and the third region measured over the first region under the same measurement conditions as when the Δr1 is measured. When Δr2 is set, Δr1 and Δr2 satisfy either one of the following formulas 3 and 4 so that the first region and the verification region do not overlap with the second region. The third region is indistinguishable visually, and the first region and the verification region DOO is in such a state that the overlapped in plan view, wherein the third region appears.
Equation 3 ... | Δr1−Δr2 |> Δr1 (where Δr2> Δr1)
Equation 4... | Δr1−Δr2 |> Δr2 (where Δr1> Δr2)
[Invention 3] An anti-counterfeit medium according to another aspect of the present invention is an anti-counterfeit medium comprising a film-like base material and a first region and a verification region including a second region and a third region. The first region has a transparent window including a scattering element, and one of the second region and the third region has a reflective layer with a concavo-convex structure, and the other region has color. The difference in the regular reflectance of the visible light between the second region and the third region measured when the surface of the base material is irradiated with visible light from a predetermined angle is defined as Δr1, and Δr1 When the difference in the regular reflectance of the visible light between the second region and the third region measured over the first region is Δr2 under the same measurement conditions as when Δr2 satisfies either one of the following formula 3 or formula 4 to In a state where one region and the verification region do not overlap, the second region and the third region are indistinguishable visually, and the first region and the verification region overlap in plan view. In that case, the third region appears.
Equation 3 ... | Δr1−Δr2 |> Δr1 (where Δr2> Δr1)
Equation 4... | Δr1−Δr2 |> Δr2 (where Δr1> Δr2)

[Invention 4 ] In the anti-counterfeit medium, the scattering element may have a concavo-convex structure.
[Invention 5 ] In the forgery prevention medium, the scattering element may be made of a resin containing fine particles.
[Invention 6 ] In the forgery prevention medium, the scattering element may be an anisotropic scattering element.
[Invention 7 ] In the forgery prevention medium, the uneven structure of the reflective layer may be a structure that reflects, diffracts, scatters, and absorbs electromagnetic waves in a specific wavelength region.

  According to the present invention, for example, it is a combination of a novel “transparent window” and “anti-counterfeit structure” that can be self-proven, and is difficult to forge because it is made of a material that is not commercially available. Since no special dye or the like is used, it is possible to provide “self-certified securities and certificates” that can be manufactured at a relatively low cost even in a large area.

The conceptual diagram which shows an example of a self-certification type | mold securities. A conceptual diagram of self-certification by folding a self-certified security in half. Sectional drawing which shows an example of the verification area | region which consists of a 2nd area | region and a 3rd area | region (the 1). Sectional drawing which shows an example of the verification area | region which consists of a 2nd area | region and a 3rd area | region (the 2). Sectional drawing which shows an example of a 1st area | region (the 1). Sectional drawing which shows an example of a 1st area | region (the 2).

Hereinafter, as an example of a forgery prevention medium according to the present invention, a self-certified security and a manufacturing method thereof will be described with reference to the drawings.
(Overall configuration example of self-certified securities)
FIG. 1 is a conceptual diagram showing a configuration example of a self-certifying certificate 1 according to an embodiment of the present invention. As shown in FIG. 1, this self-certified security 1 is formed by folding a security base material 2 as will be described later, and a first region 3 formed of a transparent window having a scattering effect provided on the security base material 2. It has the verification area | region 4 which overlaps with the 1st area | region 3 by planar view.

  The verification region 4 is composed of a second region and a third region having a fine concavo-convex structure having a reflective layer, and in the state shown in FIG. 1 (that is, a state in which the securities base material 2 is not folded), The third area is indistinguishable visually (that is, no characters appear in the verification area 4). In the self-certifying securities 1, at least one or more of the first area 3, the second area, and the third area may be prepared.

FIG. 2 is a conceptual diagram showing a self-certified security 10 folded in half and self-certifying by superimposing the first region 3, the second region 11, and the third region 12. .
As shown in FIG. 2, in the self-certified security 10 folded in half, the first region 3 and the verification region 4 made of transparent windows having a scattering effect overlap in a plan view. When the verification region 4 is observed through the first region 3, a third region 12 having a clear contrast with the second region 11 of the background appears. In this figure, the characters “TOPPAN” appear.

  FIG. 3 is a cross-sectional view illustrating a configuration example of the verification region 20 including the second region 21 and the third region 25. As shown in FIG. 3, in the verification region 20, the second region 21 and the third region 25 are constituted by fine unevenness forming layers 22 and 26 and reflective layers 23 and 27, which are adhesive layers 24 and 28. Is adhered to the securities base material 2. The second region 21 and the third region 25 have a structure in which the aspect ratio (that is, the depth / width ratio) of the fine concavo-convex structure is different.

  FIG. 4 is a cross-sectional view of the verification region 30 including the second region 31 and the third region 35. As shown in FIG. 4, in the verification region 30, the second region 31 and the third region 35 are constituted by fine unevenness forming layers 32 and 36 and reflective layers 33 and 37, which are adhesive layers 34 and 38. Is adhered to the securities base material 2. The second region 31 and the third region 35 have a structure in which the concave / convex density of the fine concavo-convex structure is different.

In FIGS. 3 and 4, the fine uneven structure is used for both the second region and the third region. However, either one of the regions is composed of a color ink in which a color pigment or a color dye and a binder resin are mixed. May be. When such an ink is observed through the first region having a scattering effect, the lightness is increased by the scattering effect, but the hue does not change greatly.
Further, the verification region may be a combination of such a layer made of color ink and a fine uneven structure in which hue and brightness change extremely over the first region. As for the color ink layer and the fine uneven structure, whichever is the second region and which is the third region. Further, a metallic pigment having a reflective layer or an interference pearl pigment may be used as a pigment as a color dye.

FIG. 5 is a cross-sectional view illustrating a configuration example of the first region 40. As shown in FIG. 5, the first region 40 has a configuration in which a scattering ink layer 41 is provided on the securities base material 2.
FIG. 6 is a cross-sectional view of the first region 50 having scattering properties, in which a non-periodic uneven structure is formed by stamping. As shown in FIG. 6, the fine unevenness forming layer 51 is composed of a plurality of grooves in a specific direction. In order to obtain white scattered light without generating a specific color tone or rainbow color, the plurality of grooves are preferably non-periodic. A transparent reflective layer 52 is provided on the surface of the fine unevenness forming layer 51 on the side having a plurality of grooves. The fine unevenness forming layer 51 and the transparent reflective layer 52 are bonded to the securities base material 2 with an adhesive 53.

By the way, in the present invention, in the self-certified security 1 shown in FIG. 1 (not folded in half), the second region and the second region measured when the surface of the security base material 2 is observed from the vertical direction. Let the color difference of the three regions be ΔE1. Also, as shown in FIG. 2, in the self-certified security 10 folded in half, under the same measurement conditions as when ΔE1 is measured (for example, using the same measurement device in the same lighting environment). The color difference between the second region and the third region measured when observed through the first region 3 is denoted by ΔE2. At this time, ΔE1 and ΔE2 satisfy one of the following formulas 1 and 2.
Formula 1 ... | ΔE1−ΔE2 |> ΔE1 (where ΔE2> ΔE1)
Expression 2 ... | ΔE1−ΔE2 |> ΔE2 (where ΔE1> ΔE2)

Alternatively, in the present invention, in the self-certified security 1 shown in FIG. 1 (in a state where the security certificate is not folded in half), the surface of the security substrate 2 is inclined from a predetermined angle (for example, 30 °, 60 °, 90). Let Δr1 be the difference in regular reflectance between the second region and the third region measured when the visible light is irradiated. Further, as shown in FIG. 2, in the self-certified security 10 folded in half, the second region measured over the first region 3 under the same measurement conditions as when Δr1 is measured, Let Δr2 be the difference in the regular reflectance of visible light in the third region. At this time, Δr1 and Δr2 satisfy one of the following formulas 3 and 4.
Equation 3 ... | Δr1−Δr2 |> Δr1 (where Δr2> Δr1)
Equation 4... | Δr1−Δr2 |> Δr2 (where Δr1> Δr2)

  When the color difference between the second region and the third region or the difference in the regular reflectance of visible light satisfies the relationship of the above formulas, the self-certificate securities 1 and 10 are in the verification region 4 before and after the folding. A display state changes remarkably, and a character, a symbol, a figure, etc. can appear with high contrast, or those that have appeared can be eliminated.

Next, each part of the above self-certified securities 1 will be described in more detail.
(First area)
The scattering ink layer 41 described above is composed of at least a binder and scattering particles. When the surface of the scattering ink layer is smooth, the refractive index difference between the binder and the scattering particles needs to be 0.2 or more. In addition to the spherical shape, needle shape, and porous shape, the scattering particle may be an amorphous particle. If the average particle diameter is 1 micron or more from the scattering constant, visible light is MIE scattered and white scattered light is emitted. When the particle size distribution is narrow, a specific wavelength is scattered, so it is preferable to select particles having a wide particle size distribution.

As a typical material of the scattering particles, organic particles such as acrylic, styrene, and urethane may be used in addition to inorganic particles such as titanium oxide, silica, and barium sulfate. Further, the first region needs to be a transparent scattering element. This is for observing the second and third regions over the first region. When the degree of scattering and the reflectance of the scattering ink layer are high, the transmittance is lowered and it is difficult to satisfy the expressions 1 to 4.
It is also possible to cause scattering by the surface irregularities of the scattering ink layer. In this case, a filler described later can be used, and an example is an aperiodic uneven structure using particles.

(Fine relief structure as the first region)
As described above, the fine concavo-convex structure as the first region may be a transparent window having a scattering structure prepared by embossing a non-periodic concavo-convex structure. Here, the scattering structure may be isotropic or anisotropic.
The isotropic scattering structure is composed of random irregularities, and emits random scattered light that does not depend on the visual rotation angle without the convex parts and concave parts being oriented in a specific direction on the plane of the fine irregular structure.
The anisotropic scattering structure is constituted by a plurality of grooves in a specific direction provided on one surface of the fine unevenness forming layer. It is characterized by emitting scattered light at a specific viewing rotation angle with respect to the light source. In order to obtain white scattered light without generating a specific color tone or rainbow color, it is preferable that the plurality of grooves have an aperiodic structure.

  In FIG. 6, a transparent reflective layer 52 is provided on the surface of the fine unevenness forming layer 51 on the side having a plurality of grooves. Examples of the transparent reflective layer 52 include, but are not limited to, zinc sulfide and titanium oxide. Any coating film having a refractive index of 0.2 or more than the fine unevenness forming layer 51 can be used. Since a uniform reflectance with a uniform film thickness is required, the transparent reflective layer 52 is preferably provided by dry coating.

(Fine relief structure as second and third regions)
The fine concavo-convex structure as the second and third regions is a structure that reflects, diffracts, scatters, and absorbs electromagnetic waves in a specific wavelength region, and includes, for example, a diffraction grating, a hologram, an isotropic scattering structure, and a different structure. Examples include, but are not limited to, a selective reflection in a specific wavelength region or a selective absorption structure by a rectangular structure having a certain depth in addition to a rectangular scattering structure, a sub-wavelength structure, and the like.
As shown in FIG. 3 or 4, the reflective layers 23, 27, or 33, 37 are provided on the surface of the fine concavo-convex structure as the second and third regions. Examples of the material for these reflective layers include, but are not limited to, metals such as gold, silver, copper, aluminum, tin, nickel, and titanium, and oxides of the metal.

The fine concavo-convex structure having the reflective layer may have a characteristic that the hue and the reflectance are remarkably changed by observing through the first region. For example, as shown in FIG. 3, the regions of the two scattering structures having different aspect ratios (depth / width ratio) of the concave shape are not greatly different in hue in the normal state, but when observed through the first region, It was confirmed that the reflectance and hue change.
As another example, as shown in FIG. 4, the two regions whose density is changed even if they have the same concave shape have no significant difference in hue in the normal state, but when viewed through the first region, the reflectance And the characteristic of changing hue.
The fine concavo-convex structure that can be used as the second and third regions of the present invention is a fine structure and has special optical effects such as reflection absorption, diffraction, and scattering in a specific wavelength region, and is difficult to replicate. And has high anti-counterfeiting properties.

  3 and 4, the second and third regions both use the fine concavo-convex structure. However, as described above, one of the second and third regions may be a color pigment or a color. You may be comprised with the color ink which mixed dye and binder resin. When such an ink is observed through the first region having a scattering effect, the lightness is increased by the scattering effect, but the hue does not change greatly.

  Such a characteristic of the color ink layer can also be used as a verification region by combining with a fine concavo-convex structure in which the hue and brightness change extremely over the first region. As for the color ink layer and the fine uneven structure, whichever is the second region and which is the third region. Further, a metallic pigment having a reflective layer or an interference pearl pigment may be used as a pigment as a color dye.

(Method for forming fine relief structure)
In order to form the fine uneven structure as the first region or the fine uneven structure as the second and third regions, a metal stamper (die) having the fine uneven structure is prepared. For example, a metal stamper may utilize a process for creating a diffraction grating. Although the method of producing a metal mold | die by nickel electroforming after producing the resin original plate of a fine uneven structure by cutting, an etching, and photolithography is mentioned as an example, It is not this. The obtained metal stamper may be pressed against the fine concavo-convex forming layer, and the fine concavo-convex structure may be replicated by a known method such as a press method or a P2 method.

If it is a press method, what is necessary is just to use the fine unevenness | corrugation formation layer which made thermoplastic resin the main material. In this case, a fine concavo-convex structure may be formed by pressing after a thermoplastic resin is coated by a known method on a supporting base material that is not softened or deformed by heat during pressing, and a fine concavo-convex formation layer is provided. Good.
When the fine concavo-convex structure is duplicated by the P2 method, the fine concavo-convex structure layer may be made of a resin that is cured by radiation. As an example of the radiation curable resin, a monomer, oligomer, polymer or the like having an ethylenically unsaturated bond can be used. Examples of the monomer include 1,6-hexanediol, neopentyl glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, and the like. . Examples of the oligomer include epoxy acrylate, urethane acrylate, and polyester acrylate. Examples of the polymer include urethane-modified acrylic resins and epoxy-modified acrylic resins.

  Examples of other photocurable resins are described in JP-A-61-98751, JP-A-63-23909, JP-A-63-23910, and JP-A-2007-118563. The photocurable resin which can be mentioned is mentioned. Moreover, in order to form fine uneven | corrugated shape correctly, polymers, such as an acrylic resin, a polyester resin, a urethane resin, and an epoxy resin, which have no reactivity can be added.

  Moreover, when utilizing photocationic polymerization, an epoxy group-containing monomer, oligomer, polymer, oxetane skeleton-containing compound, and vinyl ethers can be used. Further, when the ionizing radiation curable resin is cured by light such as ultraviolet rays, a photopolymerization initiator can be added. Depending on the resin, a radical photopolymerization initiator, a cationic photopolymerization initiator, or a combination thereof (hybrid type) can be selected.

  Examples of the photo radical polymerization initiator include benzoin compounds such as benzoin, benzoin methyl ether, and benzoin ethyl ether, anthraquinone compounds such as anthraquinone and methylanthraquinone, acetophenone, diethoxyacetophenone, benzophenone, hydroxyacetophenone, and 1-hydroxycyclohexyl. Phenyl ketone compounds such as phenyl ketone, α-aminoacetophenone, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, benzyl dimethyl ketal, thioxanthone, acylphosphine oxide, Michler's ketone, etc. be able to.

  As a photocationic polymerization initiator when using a compound capable of photocationic polymerization, aromatic diazonium salts, aromatic iodonium salts, aromatic sulfonium salts, aromatic phosphonium salts, mixed ligand metal salts, etc. should be used. Can do. In the case of so-called hybrid type materials that use both radical photopolymerization and cationic photopolymerization, each polymerization initiator can be mixed and used, and a fragrance that has the function of initiating polymerization of both with a single initiator. Group iodonium salts, aromatic sulfonium salts, and the like can be used.

  The fine unevenness forming layer according to the present invention is obtained by blending 0.1 to 15% by mass of a radiation curable resin and a photopolymerization initiator. A sensitizing dye may be used in combination with the photopolymerization initiator in the resin composition. If necessary, dyes, pigments, various additives (polymerization inhibitors, leveling agents, antifoaming agents, sagging inhibitors, adhesion improvers, coating surface modifiers, plasticizers, nitrogen-containing compounds, etc.), crosslinking An agent (such as an epoxy resin) may be included, and a non-reactive resin may be added to improve moldability. If the coating film is not cloudy, a fluorine compound or a silicone compound may be added or copolymerized in advance to improve releasability with respect to the relief original plate. May be added.

What is necessary is just to provide the thickness of a fine unevenness | corrugation layer suitably in the range of 0.1-10 micrometers. Although it depends on the viscosity (fluidity) of the uncured coating film, if the coating film is too thick, it may cause the resin of the uncured coating film to protrude or wrinkle during press processing, and is sufficient when the thickness is extremely thin. Cannot be molded.
Moreover, since the moldability changes depending on the shape of the fine irregularities of the original plate, it is preferable to provide a fine relief pattern forming layer having a thickness of 3 to 10 times the desired depth.

When the fine unevenness forming layer is provided, a coating method may be used. In particular, wet coating can be applied at a low cost. Moreover, in order to adjust a coating film thickness, you may apply | coat and dry what was diluted with the solvent. In this case, since it is provided on the uncured release layer, it is necessary to select a dilution solvent that does not re-dissolve the release layer as much as possible.
When laminating the fine unevenness layer other than the coating, prepare an uncured release layer coated on the film-like substrate and a fine unevenness forming layer provided separately to be transferred onto the film-like substrate, They may be laminated and laminated.

(radiation)
The radiation curable resin used for the fine unevenness forming layer is cured by irradiation with radiation. As the radiation, ultraviolet (UV), visible light, gamma ray, X-ray, electron beam (EB), or the like can be applied. The radiation curable resin that is cured by radiation may contain a photopolymerization initiator and / or a photopolymerization accelerator in the case of ultraviolet curing, and may not be added in the case of electron beam curing with high energy. Further, by using radiation and heat in combination, the reactivity is improved, and a coating film having a high crosslinking density can be obtained.

  The fine unevenness forming layer may be a single layer particle film in which fine particles are collected on a plane. As such a particle film, monodisperse inorganic fine particles or organic particles can be used. Examples of typical inorganic particles include silica and barium sulfate. Examples of typical organic particles include, but are not limited to, acrylic and styrene. In addition to the “pulling method” created by immersing the substrate in a solution in which the particles are mixed with the binder and gradually lifting the particle film, a known coating machine is used to utilize the surface tension of the coating liquid. A method for producing a monolayer particle film utilizing “self-organization” is known.

  The filling rate of the particle film obtained by these methods can be changed depending on the kind of the fine particle material used for the coating liquid, the blending amount of the fine particles and the binder, and the like. In particular, it is possible to absorb or scatter electromagnetic waves in a specific wavelength region by accumulating fine particles with a period shorter than the wavelength of visible light, and can be used as the structure of the second and third regions. It is. It is also possible to use single-layer particle films that differ only in the filling rate as the bond raised and recessed structure in the second and third regions.

(Securities base material)
The securities substrate may be paper, a resin film, or a laminate of paper and a resin film. In the following examples, a self-certificate certificate using a concavo-convex structure with a single layer particle film as the second and third regions will be described in detail.

  As a binder for the scattering ink, Solvain A (Nisshin Chemical Co., Ltd.) and silica particles having an average particle size of 3.4 microns were mixed at a solid weight ratio of 2/10 to prepare “scattering ink”, and then transparent The scattering ink was applied to the PET substrate in an elliptic pattern by a gravure printing method. Thereafter, an elliptical opening was provided in the securities substrate, and the above-mentioned PET substrate printed with “scattering ink” was attached to the securities substrate opening to obtain a first region.

  Next, PVAHC (Kuraray Poval Co., Ltd.) and 3300B (Mortex styrene particle size of 300 nm Co., Ltd.), which are spherical fine particles, are used as a binder of a fine particle solution for forming a monolayer particle film. The mixture was mixed at / 20, the letters “TOPPAN” were printed on a 25 μm PET film as a positive pattern, and dried in a 120 ° C. oven for 3 minutes to create a fine relief structure in the third region. The single-layer particle film in the obtained region was confirmed to have particles arranged in a single plane with an area filling rate of 82%.

  Similarly, PVAHC (Kuraray Poval Co., Ltd.) and 3300B (Mortex styrene particle size of 300 nm Co., Ltd.), which are spherical fine particles, are used as binders in the fine particle solution for forming a single layer particle film. / 15, and the letters “TOPPPAN” were printed on a 25 μm PET film as a negative pattern and dried in an oven at 120 ° C. for 3 minutes to create a fine relief structure in the second region. It was confirmed that the single-layer particle film in the obtained region had particles arranged in a single plane with an area filling rate of 60%.

Thereafter, aluminum was vapor-deposited with a thickness of 800 mm on the fine particle surfaces of the single-layer particle film in two regions by a vacuum vapor deposition method to obtain second and third regions.
The obtained second and third regions were dark green under normal light source and under normal light source, and the character pattern could not be recognized, but the second and third regions were over the first region. When observed, the positive characters "TOPPAN" were displayed in black. The above equation 1 was satisfied by measurement with a color difference meter “X-Rite 530”.

  As a binder for the scattering ink, Solvain A (Nisshin Chemical Co., Ltd.) and silica particles having an average particle size of 3.4 microns were mixed at a solid weight ratio of 2/10 to prepare “scattering ink”, and then transparent The scattering ink was applied to the PET substrate in an elliptic pattern by a gravure printing method. Thereafter, an elliptical opening was provided in the securities substrate, and the above-mentioned PET substrate printed with “scattering ink” was attached to the securities substrate opening to obtain a first region.

Next, in order to create the second and third regions, as shown below, an ink composition of a fine unevenness forming layer and an ink composition of a release layer were prepared.
Fine relief layer ink composition (ultraviolet curable resin)
Urethane (meth) acrylate (polyfunctional, molecular weight 20,000) 50.0 parts by weight Methyl ethyl ketone 30.0 parts by weight Ethyl acetate 20.0 parts by weight Photoinitiator (Irgacure 184 manufactured by Ciba Specialty) 1.5 parts by weight Thickness 23 μm A release layer ink composition was applied to a support made of transparent polyethylene terephthalate (PET) film of 1 μm so as to have a dry film thickness of 1 μm, and dried under conditions of 120 ° C. and 30 sec to form a fine unevenness forming layer. did. The obtained coating film was slightly tacky, transparent and smooth.

Thereafter, the fine unevenness forming layer ink composition is overcoated on the dry coating film of the release layer (unirradiated) so as to have a dry film thickness of 1 μm, and dried at 120 ° C. for 30 seconds to form fine unevenness. Layers were formed. The obtained coating film had almost no tackiness and was transparent and smooth.
The obtained laminate was molded by a roll photopolymer method. The original plate used for press molding is provided with a pattern of positive characters of “TOPPAN” in a pattern of non-periodic, scattering structure having a depth of 140 nm, and a fine uneven structure in the third region. A negative character of “TOPPAN” was provided in a pattern by a fine concavo-convex structure in the second region consisting of a scattering structure of

A cylindrical metal plate having a diffraction grating structure was used, and molding was performed at a press pressure of ² kgf / cm ² , a roll temperature of 80 ° C., and a press speed of 10 m / min. Simultaneously with molding, exposure was performed at 300 mJ / cm ² with a high-pressure mercury lamp, and the shape was transferred and cured at the same time.
Thereafter, aluminum was dry-coated with a thickness of 600 mm on the surface of the fine irregularities by a vacuum deposition method to obtain second and third regions.

  The obtained second region and third region normally emitted white scattered light, and the character pattern was hardly understood, but when the second and third regions were observed over the first region, “TOPPAN "" Is displayed in black. The above equation 3 was satisfied by measurement with a color difference meter “X-Rite 530”.

  The self-certified certificate of the present invention is, for example, a combination of a novel “transparent window” and “anti-counterfeit structure” that can be self-certified, and is difficult to forge because it is made of a material that is not commercially available. In addition, since no expensive special dye or the like is used, it is possible to provide “self-certified securities and certificates” that can be manufactured relatively inexpensively even in a large area. For this reason, the self-certified securities of the present invention can be used for banknotes, official documents, etc. having high anti-counterfeiting properties.

DESCRIPTION OF SYMBOLS 1 ... Self-certification type | mold securities 2 ... Securities base material 3 ... 1st area | region 4 ... Verification area | region 10 ... Self-certification type | mold securities 11 folded in half ... 2nd area | region 12 ... 3rd area | region 20 ... Verification area | region (FIGS. 1, 2) Example of verification area 4 shown in FIG.
21 ... 2nd area | region (an example of the 2nd area | region 11 shown in FIG. 2)
22 ... fine unevenness forming layer 23 ... reflective layer 24 ... adhesive layer 25 ... third region (an example of the third region 12 shown in FIG. 2)
26 ... fine unevenness forming layer 27 ... reflective layer 28 ... adhesive layer 30 ... verification region (an example of the verification region 4 shown in FIGS. 1 and 2)
31 ... 2nd area | region (an example of the 2nd area | region 11 shown in FIG. 2)
32 ... Fine unevenness forming layer 33 ... Reflective layer 34 ... Adhesive layer 35 ... Third region (an example of the third region 12 shown in FIG. 2)
36 ... fine unevenness forming layer 37 ... reflective layer 38 ... adhesive layer 40 ... first region (an example of the first region 3 shown in Figs. 1 and 2)
41 ... Scattering ink layer 50 ... First region 51 with fine structure ... Fine structure forming layer 52 ... Transparent reflective layer 53 ... Adhesive layer

Claims (7)

An anti-counterfeit medium comprising a first region and a verification region including a second region and a third region on a film-shaped substrate,
The first region has a transparent window including a scattering element;
It said second region and said third region has each reflective layer of the aspect ratio or density differs uneven structure of the recess to each other,
ΔE1 is the color difference between the second region and the third region measured when the surface of the substrate is observed from the vertical direction;
When the color difference between the second region and the third region measured when the surface of the base material is observed through the first region under the same measurement conditions as when the ΔE1 is measured is ΔE2.
The ΔE1 and the ΔE2 satisfy either one of the following formulas 1 or 2, and when the first region and the verification region do not overlap, the second region and the third region The forgery prevention medium is characterized in that the third region appears when the first region and the verification region overlap each other in a plan view.
Formula 1 ... | ΔE1−ΔE2 |> ΔE1 (where ΔE2> ΔE1)
Expression 2 ... | ΔE1−ΔE2 |> ΔE2 (where ΔE1> ΔE2) An anti-counterfeit medium comprising a first region and a verification region including a second region and a third region on a film-shaped substrate,
The first region has a transparent window including a scattering element;
It said second region and said third region has each reflective layer of the aspect ratio or density differs uneven structure of the recess to each other,
Δr1 is a difference in regular reflectance of the visible light between the second region and the third region measured when the surface of the substrate is irradiated with visible light from a predetermined angle;
When the difference in the regular reflectance of the visible light between the second region and the third region measured over the first region is Δr2 under the same measurement conditions as when the Δr1 is measured,
The Δr1 and the Δr2 satisfy either one of the following formula 3 or formula 4 so that the first region and the verification region do not overlap with each other, the second region and the third region The forgery prevention medium is characterized in that the third region appears when the first region and the verification region overlap each other in a plan view.
Equation 3 ... | Δr1−Δr2 |> Δr1 (where Δr2> Δr1)
Equation 4... | Δr1−Δr2 |> Δr2 (where Δr1> Δr2)   An anti-counterfeit medium comprising a first region and a verification region including a second region and a third region on a film-shaped substrate,
  The first region has a transparent window including a scattering element;
  One of the second region and the third region has a reflective layer with a concavo-convex structure, and the other region is composed of ink having a color,
  Δr1 is a difference in regular reflectance of the visible light between the second region and the third region measured when the surface of the substrate is irradiated with visible light from a predetermined angle;
  When the difference in the regular reflectance of the visible light between the second region and the third region measured over the first region is Δr2 under the same measurement conditions as when the Δr1 is measured,
  The Δr1 and the Δr2 satisfy either one of the following formula 3 or formula 4 so that the first region and the verification region do not overlap with each other, the second region and the third region The forgery prevention medium is characterized in that the third region appears when the first region and the verification region overlap each other in a plan view.
      Equation 3 ... | Δr1−Δr2 |> Δr1 (where Δr2> Δr1)
      Equation 4... | Δr1−Δr2 |> Δr2 (where Δr1> Δr2) The scattering element medium for preventing forgery according to claims 1 to any one of claims 3, characterized in that it is constituted by a concave-convex structure. The medium for preventing forgery according to any one of claims 1 to 3, wherein the scattering element, characterized in that is constituted by a resin containing fine particles. The forgery prevention medium according to any one of claims 1 to 5 , wherein the scattering element is an anisotropic scattering element. The forgery prevention medium according to any one of claims 1 to 6 , wherein the uneven structure of the reflective layer is a structure that reflects, diffracts, scatters, and absorbs electromagnetic waves in a specific wavelength region.

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