JP2014052527A - Display body, article with display body, and method for determining authenticity of the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display body having a higher counterfeit preventing effect than a hologram single body, and a method for determining authenticity of the display body.SOLUTION: The display body includes, on one surface of a light-transmitting substrate 10: a structure formation layer 11 having a first region including a fine rugged structure and a second region having a smooth surface; a reflection layer 12 that covers at least the fine rugged structure of the first region; and a fine particle layer 13 on the smooth surface of the second region or inside the surface. The light reflection layer 12 is formed of a metal material or a dielectric material and is configured to develop at least one optical effect of diffraction, interference, scattering and absorption by the fine rugged structure.

Description

  The present invention relates to an anti-counterfeiting technique that combines an optical effect caused by a fine concavo-convex structure with a coloration effect caused by arrangement of fine particles, and a method for determining the authenticity of a display using the same.

  Articles such as securities, certificates, branded products, electronic devices and personal authentication media are desired to be difficult to counterfeit. For this reason, such an article may support a display body having an excellent anti-counterfeit effect.

  Various structures are known as display bodies that have been subjected to anti-counterfeit technology (Patent Documents 1 to 8). For example, in Patent Document 1, in order to increase the security level of a fluorescent image formation using a fluorescent light emitting ink, a fluorescent image formation containing two types of phosphors having different wavelength regions of fluorescence emitted from the respective phosphors Is used. Patent Document 3 discloses an intaglio latent image that can be confirmed only from a specific angle. Patent Document 4 discloses a medium for authenticity determination using a combination of a hologram layer, a light reflective layer, and an alignment film.

  In recent years, authenticity determination media provided with holograms have been widely used. Here, the hologram is formed by a relief type diffraction grating, and is characterized in that diffracted light shining in rainbow can be observed. The consumer can determine the authenticity by confirming the diffracted light that shines in the rainbow color.

  However, since the medium for authenticity determination provided with a hologram has come to be widely used, the hologram technology has been widely recognized. Furthermore, holograms are now used for decorative films and the like. In response to these trends, the generation of counterfeit products for authenticity determination media provided with holograms is increasing. Therefore, there is a problem in providing a sufficient anti-counterfeit effect only with the feature that the diffracted light is rainbow-colored.

Japanese Patent Laid-Open No. 10-250214 JP 2004-181791 A JP 11-291609 A JP 2005-091786 A Japanese translation of PCT publication No. 2002-530687 JP 2009-535670 A JP-A-5-273500 JP 2008-139508 A

  An object of the present invention is to solve the conventional problems as described above, and to provide a display body having a higher forgery prevention effect than a hologram alone.

The invention according to claim 1 for achieving the above object is provided on one surface of a light-transmitting substrate.
A structure forming layer comprising a first region comprising a fine relief structure and a second region comprising a smooth surface;
A reflective layer covering at least the fine relief structure of the first region;
The display body is characterized by having a fine particle layer on or inside the smooth surface of the second region.

  The invention according to claim 2 of the present invention is the display body according to claim 1, wherein the light reflecting layer is made of a metal material or a dielectric material.

  The invention according to claim 3 of the present invention is characterized in that at least one optical effect among diffraction, interference, scattering, and absorption is expressed by the fine concavo-convex structure. This is a display body.

  The invention according to claim 4 of the present invention is characterized in that the fine particle layer is composed of spherical fine particles having an average particle size of 100 nm or more and 1000 nm or less selected from any of organic substances, inorganic substances, and metals. The display body according to any one of claims 1 to 3.

  In the invention according to claim 5 of the present invention, the fine particle layer is composed of spherical fine particles and a light-transmitting embedding resin that embeds a gap between the spherical fine particles, and the refractive index of the fine particles and the embedding resin. The display body according to any one of claims 1 to 4, wherein the difference is 0.01 or more and 0.80 or less. It is what.

  The invention according to claim 6 of the present invention is the display body according to claim 5, wherein in the fine particle layer, most of the fine particle portions are voids.

  According to a seventh aspect of the present invention, the display body according to any one of the first to sixth aspects is applied to an article via a light-transmitting adhesive layer formed on the light reflecting layer. It is an article with a display body, which is pasted so as to cover an opening provided in a supporting body to which it belongs.

An invention according to claim 8 of the present invention is the display body according to any one of claims 1 to 6,
A method for determining authenticity of a display body is characterized in that a black substrate is placed on the back surface of the display body, and whether or not a region corresponding to the fine particle layer shows a desired color state is visually confirmed.

The invention according to claim 9 of the present invention is the display body according to any one of claims 1 to 6,
A white substrate is installed on the back surface of the display body, and it is visually confirmed whether or not the region corresponding to the fine particle layer shows a desired color state. Further, a black substrate is installed on the back surface of the display body to correspond to the fine particle layer. A method for judging the authenticity of a display body, characterized by visually checking whether or not a region shows another desired color state and checking whether the first and subsequent color states are in a complementary color relationship It is.

According to the present invention, it is possible to provide a plurality of anti-counterfeit functions by combining a fine concavo-convex structure exhibiting an optical effect and a fine particle layer, and a display body having a more advanced anti-counterfeit effect, and an article with a display body Can be provided.
In addition, there is an effect that the authenticity of the display body can be easily determined by visually observing the colored state when the background color of the fine particle layer is changed.

FIG. 6 is a cross-sectional view illustrating an example of a display body according to one embodiment of the present invention. Sectional drawing which shows the other example of the display body which concerns on 1 aspect of this invention. Sectional drawing which shows the other example of the display body which concerns on 1 aspect of this invention. Sectional drawing which shows the other example of the display body which concerns on 1 aspect of this invention. The perspective view which shows an example of a fine uneven structure. The perspective view which shows the other example of a fine uneven structure. FIG. 7 is a schematic diagram for explaining a light interference phenomenon by the fine concavo-convex structure shown in FIG. 6. The perspective view which shows the other example of a fine uneven structure. The perspective view which shows the other example of a fine uneven structure. The perspective view which shows the other example of a fine uneven structure. Sectional drawing which shows the diffraction of the light in a fine particle layer. The schematic diagram which shows an example of the article | item with a display body which concerns on 1 aspect of this invention. Sectional drawing in alignment with the AA in FIG. The schematic diagram which shows an example of the authenticity determination method of the articles | goods with a display body which concerns on 1 aspect of this invention. The schematic diagram which shows the other example of the authenticity determination method of the articles | goods with a display body which concerns on 1 aspect of this invention. The schematic diagram which shows the other example of the authenticity determination method of the articles | goods with a display body which concerns on 1 aspect of this invention. Sectional drawing which shows the other example of the display body which concerns on 1 aspect of this invention.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In addition, the same referential mark is attached | subjected to the component which exhibits the same or similar function through all the drawings, and the overlapping description is abbreviate | omitted.

  FIG. 1 is a cross-sectional view illustrating an example of a display body according to one embodiment of the present invention. 2, 3 and 4 are also cross-sectional views of a display body according to another aspect of the present invention. In FIG. 1, FIG. 2, FIG. 3, and FIG. 4, directions parallel to the main surface of the display body 100 and perpendicular to each other are defined as an X direction and a Y direction. Yes.

  A display body 100 shown in FIG. 1 includes a base material 10, a structure forming layer 11 laminated on the base material 10, a light reflection layer 12, and a fine particle layer 13 composed of a plurality of fine particles 14. . Here, the base material 10, the structure forming layer 11, the light reflecting layer 12, and the fine particle layer 13 are collectively referred to as a laminate 200.

  The substrate 10 may have a single layer structure or a multilayer structure. Further, a material having optical anisotropy such as cholesteric liquid crystal may be laminated. The substrate 10 has a thickness that can support the structure forming layer 11, the light reflecting layer 12, and the fine particle layer 13, and a PET film, a CPP film, an OPS film, or the like can be used as the material. .

  On one main surface of the structure forming layer 11, a first region DM1 and a second region DM2 are formed. In the first region DM1, a fine uneven structure, which will be described later, is formed, and the second region DM2 is generally a smooth surface without a conscious structure like DM1. As a material of the structure forming layer 11, for example, a thermoplastic resin, a thermosetting resin, a photocurable resin, or the like can be used.

  However, the structure forming layer 11 may include a plurality of regions where a structure different from the fine concavo-convex structure formed in the first region DM1 is formed.

  The structure forming layer 11 may have a single layer structure or a multilayer structure. Furthermore, the structure forming layer 11 may be colored by adding a dye to the resin under the condition that the light transmittance is not significantly reduced. Further, fine particles made of metal, semiconductor, ceramic, magnetic material, or the like may be added.

Further, it can be used as the material of the structure formation layer 11, for example, SiO ₂ or _TiO 2, MgF ₂ inorganic materials or mixtures thereof and the like. When the inorganic material is used as the structure forming layer 11, for example, a thin film forming technique such as vapor deposition or sputtering can be used. In addition, when forming a fine concavo-convex structure in an inorganic material, it is possible to use a technique such as chemical etching or laser processing.

  The light reflecting layer 12 covers the first region DM1 in which at least the fine uneven structure is formed in the first region DM1 and the second region DM2 provided in the structure forming layer 11. Covering the first region DM1 with the light reflecting layer 12 makes it easier to visually observe the optical effect described later. In the display body 100 shown in FIGS. 1 to 4, the light reflecting layer 12 is formed on the fine uneven structure of the first region DM1.

Examples of the material of the light reflecting layer 12 include metal materials such as aluminum, nickel, chromium, iron, copper, silver, and gold. The light reflecting layer 12 may have a single layer structure or a multilayer structure. Further, it may be a single layer structure or a multilayer structure of an inorganic material such as SiO ₂ , TiO ₂ , MgF _2, a mixture thereof, or a dielectric material.

  The light reflecting layer 12 can be formed by a thin film forming technique such as vapor deposition and sputtering, for example. Furthermore, in order to distribute the light reflecting layer 12 in a pattern on a plane, techniques such as mask vapor deposition, chemical etching, and laser processing are used. An image can also be expressed using the distribution of the light reflecting layer 12 by making the light reflecting layer 12 have a planar pattern distribution in the first region DM1.

  The fine particle layer 13 is formed by the arrangement of the fine particles 14 on the upper surface of a region corresponding to the second region DM2 provided in the structure forming layer 11. By arranging the fine particles 14 to form the fine particle layer 13, an optical effect described later can be obtained.

Examples of the material of the fine particles 14 include organic materials such as polystyrene and acrylic, inorganic materials such as SiO ₂ , TiO ₂ , MgF ₂ , and ZnO, metal materials such as gold, silver, copper, and aluminum, and ceramic materials. Further, functional fine particles and core-shell structured fine particles may be used.

  The display body 100 shown in FIG. 2 is a case where the fine particle layer 13 is formed inside the structure forming layer 11 in the form shown in FIG. By so doing, the same optical effect as that of the display body 100 shown in FIG. 1 can be imparted.

  The display body 100 shown in FIG. 3 is the case where the embedding resin 15 is formed on the structure forming layer 11 so as to cover the fine particle layer 13 in the form shown in FIG. By covering with the embedding resin 15, it is possible to prevent the arrangement of the fine particle layer 13 from collapsing. Here, the refractive index difference between the fine particles 14 forming the fine particle layer 13 and the embedding resin 15 is 0.01 or more and 0.8 or less in order to express the optical effect described later more effectively. It is good to choose.

  The display body 100 shown in FIG. 4 is a case where the fine particle 14 portion is a void 16 in the embodiment shown in FIG. Although it is not necessary that all are voids, by providing the voids, in addition to the optical effect, it is possible to accompany the dynamic response described later.

  In the display body 100 shown in FIGS. 1, 2, 3, and 4, as an example, the light reflecting layer 12 is positioned on the front side with respect to the structure forming layer 11, and the fine particle layer 13 is located on the light reflecting layer 12. On the other hand, it is the structure located in the front side. The light reflecting layer 12 may be positioned on the rear surface side of the structure forming layer 11, and the fine particle layer 13 may be positioned on the rear surface side of the light reflecting layer 12.

Furthermore, the fine particles 14 and the voids 16 in the display body 100 shown in FIGS. 1, 2, 3, and 4 are provided in contact with each other, but the embedding resin 15 in FIGS. 2 to 4 exists. In some cases, non-contact structures are possible.

  Hereinafter, a detailed configuration and optical effect of the display body 100 shown in FIGS. 1, 2, 3, and 4 will be described.

  As described above, the structure forming layer 11 includes the first region DM1 and the second region DM2. Specifically, in the first region DM1, a fine concavo-convex structure is formed on the XY plane as shown in FIG. 5, FIG. 6, FIG. 8, FIG. Each fine concavo-convex structure has a structure that exhibits at least one optical effect among diffraction, interference, scattering, and absorption.

  The fine concavo-convex structure shown in FIG. 5 schematically illustrates a structure that exhibits a diffraction optical effect, and is generally a structure called a diffraction grating. For example, the diffraction grating is formed by arranging a plurality of grooves. The “diffraction grating” means a structure that generates diffracted light when irradiated with illumination light. For example, in addition to a normal diffraction grating in which a plurality of grooves are arranged in parallel and at equal intervals, interference fringes recorded in a hologram Is also included. The depth of the grooves constituting the diffraction grating is typically in the range of 0.01 μm or more and 1.00 μm or less. The period of the diffraction grating is typically in the range of 0.20 μm or more and 5.00 μm or less.

  The diffraction grating structure shown in FIG. 5 is periodically arranged with respect to the X-axis direction, but may be periodically arranged with respect to the Y-axis direction, and further periodically in the XY plane. May be arranged. In the diffraction grating structure shown in FIG. 5, line structures substantially parallel to the Y-axis direction are periodically arranged with respect to the X-axis direction, but not only a line structure substantially parallel to the Y-axis direction but also a curved structure. It may be.

  The fine concavo-convex structure shown in FIG. 6 depicts a structure that exhibits an optical effect of interference. Here, the bottom surface of the recess PIT <b> 1 is formed so as to be substantially parallel to the main surface of the base material 10 or the main surfaces of the structure forming layer 11 and the light reflecting layer 12. By doing so, a phase difference is generated between the incident lights IL1 and IL2 as shown in FIG. 7, and light in a specific wavelength region is weakened or strengthened by interference with each incident light.

  In FIG. 6, the recesses PIT1 are randomly formed on the XY plane, but may be formed periodically. Further, the shape of the recess PIT1 may be a square shape, a rectangular shape, a circular shape, or a polygonal shape. By changing the shape of the recess PIT1, the directivity of the interference light can be changed. The average depth of the recess PIT1 is typically in the range of 0.10 μm or more and 1.00 μm or less.

  The fine concavo-convex structure shown in FIGS. 8 and 9 depicts a structure that exhibits the optical effect of scattering. Specifically, the fine uneven structure shown in FIG. 8 is a structure that generates directional scattered light, and the fine uneven structure shown in FIG. 9 is a structure that generates omnidirectional scattered light. The convex portions PIT2 depicted in FIG. 8 have a convex structure that is substantially parallel to the Y-axis direction and has a finite length on the XY plane, and are arranged in a random cycle in the X-axis direction. With such a structure, scattered light having directivity in the X-axis direction is emitted. The average height of the convex portion PIT2 is typically in the range of 0.01 μm or more and 1.00 μm or less, and the average height of each convex portion PIT2 is randomly selected within the range. Furthermore, the arrangement interval of the convex portions PIT2 in the X-axis direction is typically in the range of 0.20 μm or more and 5.00 μm or less, and the arrangement interval of the respective convex portions PIT2 is randomly selected within the range.

Although the convex portions PIT2 are arranged in the X-axis direction in FIG. 8, they may be arranged in the Y-axis direction, or may be arranged in a specific direction for each specific region in the XY plane. Further, it may have a curved structure.

  In the fine concavo-convex structure shown in FIG. 9, the convex portions PIT3 are randomly arranged in the XY plane in order to generate omnidirectional scattered light as described above. Since the incident light is scattered by the convex portions PIT3 arranged at random, it becomes possible to emit non-directional scattered light. The convex portions PIT3 may all have the same shape as shown in FIG. 9, but each PIT3 may have a different shape. By doing so, it becomes possible to further enhance omnidirectionality. Here, the average height of the protrusions PIT3 is typically in the range of 0.10 μm or more and 1.00 μm or less, and the average height of each protrusion PIT3 is randomly selected within the range.

  The fine concavo-convex structure shown in FIG. 10 depicts a structure that exhibits optical effects of diffraction and absorption. Since the convex portions depicted in FIG. 10 are periodically arranged in two directions of the X-axis direction and the Y-axis direction, they have a structure that behaves like a diffraction grating. The structure emits diffracted light in the direction. Furthermore, the structure pitch of the convex structure is 100 nm or more and 500 nm or less, within the range shorter than the visible light region, or the same pitch as the short wavelength region, so it behaves like a moth-eye structure and exhibits an optical absorption effect. Is done.

  In FIGS. 5, 6, 7, 8, 9, and 10, the fine concavo-convex structure constituted by the concave portions or the convex portions is depicted, but the same applies even if the concave portions and the convex portions are reversed. Optical effects can be obtained.

  In the display body 100 shown in FIGS. 1, 2, 3, and 4, the fine uneven structure shown in FIGS. 5, 6, 8, 9, and 10 described above is formed in the first region DM <b> 1. As a result, various optical effects can be exhibited. Furthermore, by forming a plurality of fine uneven structures in the first region DM1, it is possible to draw an image using a plurality of optical effects.

  The light reflecting layer 12 is formed so as to cover at least the first region DM1 in the structure forming layer 11, and the optical effect of the fine concavo-convex structure described above can be more easily understood during visual observation. In addition, by forming with a metal material, it becomes possible to have a metallic luster and to express an optical effect, and to improve the design. When a metal material is used as the light reflecting layer 12, a typical layer thickness is in a range of 10 nm to 100 nm.

  Furthermore, it is also possible to use a dielectric material as the light reflecting layer 12, and by doing so, it becomes possible to develop an optical effect while maintaining light transmittance. When a dielectric material is used as the light reflecting layer 12, a typical layer thickness is in the range of 10 nm to 100 nm.

  In addition, it is possible to impart design to the display body 100 by partially removing the light reflecting layer 12 and patterning it.

  In the structure forming layer 11 described above, the fine particle layer 13 (or the void 16 in FIG. 4) is positively provided in the second region DM2 as shown in FIG. 1, FIG. 2, FIG. 3, and FIG. The average particle diameter φ of the fine particles 14 or the voids 16 forming the fine particle layer 13 is preferably 100 nm or more and 1000 nm or less, and more preferably 150 nm or more and 400 nm or less. By doing so, an optical effect described later is easily understood during visual observation.

The fine particle layer 13 has an optical effect to be described later by arranging a plurality of fine particles 14 or voids 16 in a three-dimensional manner. The arrangement pattern of the fine particle layer 13 can be an FCC structure (: Face-Centered Cubic face-centered cubic lattice structure) or a BCC structure (: Body-Centered Cubic body-centered cubic lattice) depending on the conditions for arranging the fine particles 14. . As described above, the crystal structure is different, the structure pitch between the fine particles is different, and the optical effect described later is also different.

FIG. 11 shows a schematic view of the fine particle layer 13 taken in the Z direction. FIG. 11 shows a state in which the fine particles 14 are arranged in an ideal periodic arrangement in the fine particle layer 13. When incident light IL3 is incident on the structure, the following structure 1 is satisfied by the arrangement structure. Light diffraction occurs.
mλ = 2nd · sin θ (Formula 1)
Here, m: diffraction order, λ: wavelength of diffracted light (in the medium), n: medium refractive index, d: structure pitch, θ: light source incident angle.
From Equation 1, it can be seen that a specific wavelength is enhanced by diffraction when θ is fixed by the structure pitch of the fine particles 14.

  The structure in which the fine particles 14 are arranged three-dimensionally like the fine particle layer 13 is known as an opal crystal, and the wavelength of the diffracted light depends on the structure pitch of the fine particles 14 and the average particle diameter φ of the fine particles 14. It is well known to change.

  In the present invention, the arrangement of the fine particles 14 in the fine particle layer 13 is determined by the average particle diameter φ of the fine particles 14 and the conditions when arranging the fine particles 14. Therefore, by satisfying predetermined conditions such as the average particle diameter φ and arrangement conditions of the fine particles 14, it is possible to obtain the fine particle layer 13 that strongly diffracts light having a desired wavelength.

  The average particle diameter φ of the fine particles 14 is set to 100 nm or more and 1000 nm or less in the present invention. In Equation 1, when the light source incident angle θ is 90 degrees, the wavelength λ of the diffracted light is twice the structure pitch d (when the refractive index of the medium n = 1 and the diffraction order m = 1). Further, when the fine particles 14 have a close-packed structure pattern, the structural pitch d is the same as the average particle diameter φ of the fine particles 14, and therefore when the average particle diameter φ is 150 nm or more and 400 nm or less, light having a wavelength in the visible light region is emitted. Since it is diffracted, visual observation becomes easy. Further, in order to change the observation angle or observe the diffracted light having the diffraction order m = 2, the average particle diameter φ can be selected from a range of 100 nm to 1000 nm.

  The light diffraction effect cannot be obtained unless at least two fine particle layers 13 are laminated. In FIGS. 1, 2, 3, and 4, all three layers are illustrated, but three or more layers may be stacked. As the number of layers increases, the intensity of diffracted light increases. Observation of diffracted light becomes easy.

  In the fine particle layer 13, the fine particles 14 are arranged with a specific structure pitch and a specific average particle diameter φ to generate diffracted light, and light that can be observed when the fine particle layer 13 is observed exhibits a chromatic color. The chromatic colors are called structural colors.

  In FIG. 1, since the fine particle layer 13 is disposed on the front side of the structure forming layer 11, there is a risk that the fine particle layer 13 is easily broken by an external impact. In that case, it is preferable to fix the fine particle layer 13 using the embedding resin 15 as shown in FIG. The embedding resin 15 needs to have light permeability.

  Here, the light transmittance in the present invention means that the display body and the article with the display body of the present invention are observed through a light source such as natural light, sunlight, or a fluorescent light, so that light is transmitted through the display body 100 and the laminate 200. And can be observed visually.

  When selecting the embedding resin 15, the difference in refractive index from the fine particles 14 is important. When the refractive index difference is small, the amount of light diffracted by the fine particles 14 in the embedding resin 15 is reduced, and visual observation of the diffracted light becomes difficult. Therefore, it is desirable that the difference in refractive index is at least 0.01.

  Moreover, the refractive index of the high refractive index resin which is generally available at present is about 1.70. In addition, when the refractive index of the fine particles 14 is 1.00 (in the case of voids, it is greater than 1 in the case of resin), the refractive index difference can be about 0.70 at the maximum.

  From the above, when using the embedding resin 15, it is necessary to pay attention to the difference in refractive index from the fine particles 14 and to set the difference in refractive index between 0.01 and 0.80.

  When the fine particles 14 are fixed with the embedding resin 15, the fine particle layer 13 can be formed by the gaps 16 as shown in FIG. 4. In particular, if the gap 16 is air (refractive index 1.0), the refractive index difference from the embedding resin 15 becomes larger.

  The display body 100 shown in FIG. 3 is formed using the fine particles 14 that can be dissolved or decomposed, and then the fine particles 14 are dissolved or decomposed to obtain the fine particle layer 13 with the voids 16 as shown in FIG. By doing so, the refractive index difference between the embedding resin 15 and the gap 16 can be increased as described above, and the diffracted light can be easily visually observed.

  Furthermore, in the display body 100 shown in FIG. 4, when the embedded resin 15 having elasticity is used, the structure pitch of the gaps 16 is changed by applying pressure to the display body 100, and the coloration by the diffracted light is changed. It becomes possible to make it.

  In addition, the coloration by the diffracted light can be changed by filling the gap 16 with a liquid material having a refractive index different from that of the embedding resin 15.

  12 and 13 illustrate a case where the display body-equipped article 300 illustrated in FIG. 12 and FIG. 13 is provided with a light-transmitting adhesive layer 52 in the display body 100 and the display body 100 is affixed to a support body 50 having a light transmission portion 51. Yes. In FIG. 12, the display body 100 is pasted so as to cover the entire region of the light transmission part 51. FIG. 13 depicts a cross-sectional view along the line AA in FIG. If the support 50 is a light-impermeable material (for example, a paper base material), the light-transmitting portion 51 is obtained by providing an opening in the support 50. On the other hand, if the support 50 is a light transmissive material (for example, a polymer base material), the entire base material can be used as the light transmissive portion 51.

  The display body 100 is configured to include the light reflecting layer 12, and the light reflecting layer 12 is partially removed, and the fine particle layer 13 is juxtaposed. Therefore, when the adhesive layer 52 having light transmittance is provided and the display body 100 is attached to the support body 50 having the light transmitting portion 51, the light reflecting layer 12 does not transmit light in the region where the light reflecting layer 12 is formed. In the region where 12 is removed and the fine particle layer 13 is formed, light is transmitted. By doing so, the authenticity determination method described later becomes easy to understand.

  The light-transmitting adhesive layer 52 may be provided on the substrate 10 side of the display body 100, or may be provided on the side where the light reflecting layer 12 and the fine particle layer 13 are formed (described later). Except for the embodiment shown in FIG.

  FIG. 14 illustrates a case where a black substrate 400 is installed on the back surface of the article 300 with a display body. By doing so, in the fine particle region 60 provided with the fine particle layer 13, the coloration by the diffracted light becomes clear, and visual observation becomes easy. Further, by selecting the refractive index of the fine particles composing the fine particle layer 13 at the time of forming the display body 100, it is colorless during normal observation, but by installing the black substrate 400 on the back surface of the display-equipped article 300, For the first time, it is possible to visually confirm the coloration by diffracted light.

FIG. 15 illustrates a case where the white substrate 410 is installed on the back surface of the display-equipped article 300. By doing so, in the fine particle region 60 provided with the fine particle layer 13, the second color that is complementary to the first color by the diffracted light can be visually observed. Furthermore, by selecting the refractive index of the fine particles forming the fine particle layer 13 at the time of forming the display body 100, it is colorless during normal observation, but by installing the black substrate 400 on the back surface of the display-equipped article 300, The first coloration by the diffracted light is visually confirmed for the first time, then the white substrate 410 is installed, and the second coloration that is complementary to the first coloration can be visually confirmed.

  By using the black substrate 400 and the white substrate 410 for the first coloration by the diffracted light and the second coloration that is complementary to the first coloration as described above, it is possible to determine the authenticity by visually confirming the coloration. It becomes.

  FIG. 16 illustrates a case where the observer OB observes the display-equipped article 300 and the display body 100 with transmitted light. By doing so, it is possible to obtain the same effect as that shown in FIG. Specifically, since the display body 100 is visually confirmed through transmission using a background at infinity, the back surface of the article with the display body is virtually synonymous with black, and in the fine particle region 60 provided with the fine particle layer 13. The coloration by the diffracted light can be visually confirmed.

  FIG. 17 illustrates a case where the fine particle layer 13 is formed on the upper surface of the light reflecting layer 12. Here, when the light reflection layer 12 is made of a metal material, the second region DM2 has a colored metallic tone due to the coloration of the fine particle layer by the diffracted light and the reflected light from the metal material.

  The display body 100 and the display body-equipped article 300 have different color saturation due to diffracted light depending on the irradiation light source. Specifically, when the display body 100 and the article 300 with a display body are illuminated using an LED light source, it is possible to visually check a highly saturated color.

  By providing the fine particle layer 13 on the display body 100 and the display body-equipped article 300 as described above, the first coloration by the diffracted light is confirmed, and further the second coloration that is the complementary color relationship is confirmed. Therefore, the forgery prevention effect can be enhanced.

  Furthermore, since the optical effect by the fine concavo-convex structure formed in the first region DM1 in the structure forming layer 11 is manifested by the fine concavo-convex structure, forgery by a normal printing technique or processing technique becomes difficult.

  The display body 100 described above can be used, for example, by being attached to a printed material, a card medium, or other articles via an adhesive as an anti-counterfeit label. Furthermore, it can be used for purposes other than forgery prevention. For example, the display body 100 and the display body-equipped article 300 can be used as toys, learning materials, ornaments, and the like.

  Specific examples of the present invention will be described below, but the present invention is not limited to this embodiment.

  An ultraviolet curable resin corresponding to the structure forming layer was applied to the PET film with a gravure roll coater to obtain a film for forming a fine uneven structure.

  Next, in order to form a fine concavo-convex structure and a smooth surface on the film for forming a fine concavo-convex structure, a metal plate having a diffraction grating structure having an average period of 1 μm and a smooth surface was prepared.

Next, an ultraviolet curable resin was pressed against the metal plate, irradiated with ultraviolet rays from a metal halide lamp, and after curing the ultraviolet curable resin, the metal plate was peeled off to form a fine concavo-convex structure and a smooth surface. Then, aluminum was vapor-deposited so that it might become a film thickness of about 100 nm by the vacuum evaporation method, the light reflection layer was provided, and the aluminum of the smooth surface part was removed by the chemical etching process.

On the interface region where the fine concavo-convex structure is formed and the light reflecting layer is deposited, SiO ₂ fine particles having a particle diameter of 132 nm are 10 wt.% Relative to the PETA (pentaerythritol triacrylate) monomer. % Dispersed resin monomer was dropped and cured to obtain a display.

In the display obtained as described above, the diffracted light by the diffraction grating structure and the blue-green and cloudy coloration by the SiO ₂ fine particles could be visually confirmed. Furthermore, when a black board | substrate was installed in the back surface of the display body and it confirmed visually, the saturation of the blue-green coloration became high and it has confirmed that observation became easier. Furthermore, by using a white substrate for the back surface, it was possible to visually confirm the orange color that is complementary to the blue-green color.

An ultraviolet curable resin corresponding to the structure forming layer was applied to the PET film with a gravure roll coater to obtain a film for forming a fine uneven structure.
Next, in order to form a fine concavo-convex structure and a smooth surface on the film for forming a fine concavo-convex structure, a metal plate having a diffraction grating structure having an average period of 1 μm and a smooth surface was prepared.

  Next, an ultraviolet curable resin was pressed against the metal plate, irradiated with ultraviolet rays from a metal halide lamp, and after curing the ultraviolet curable resin, the metal plate was peeled off to form a fine concavo-convex structure and a smooth surface. Then, aluminum was vapor-deposited so that it might become a film thickness of about 100 nm by the vacuum evaporation method, the light reflection layer was provided, and the aluminum of the smooth surface part was removed by the chemical etching process.

On the interface region where the fine concavo-convex structure is formed and the light reflecting layer is deposited, SiO ₂ fine particles having a particle diameter of 132 nm are 20 wt. % Dispersed resin monomer was dropped and cured to obtain a display.

In the display body obtained as described above, the diffracted light by the diffraction grating structure could be visually confirmed, but the coloration of the diffracted light by the SiO ₂ fine particles could not be visually confirmed.

Next, when a black substrate was installed on the back surface of the display body and visually confirmed, blue coloration was visually confirmed as the coloration of diffracted light by the SiO ₂ fine particles. Furthermore, by making the back surface a white substrate, it was possible to visually confirm the yellow color that is complementary to blue.

DESCRIPTION OF SYMBOLS 10 ... Base material 11 ... Structure formation layer 12 ... Light reflection layer 13 ... Fine particle layer 14 ... Fine particle 15 ... Embedded resin 16 ... Void 30 ... Fine particle arrangement surface 50 ... Support body 51 ... Light transmission part 52 ... Adhesive layer 60 ... Fine particle Area 100 ... Display body 200 ... Laminated body 300 ... Display-equipped article 400 ... Black substrate 410 ... White substrate φ ... Average particle diameter DM1 ... First area DM2 ... Second area PIT1 ... Concave part PIT2 ... Convex part PIT3 ... Convex part IL ... Incident light θ ... Light source incident angle d ... Fine particle structure pitch OB ... Observer

Claims (9)

On one side of the substrate having light permeability,
A structure forming layer comprising a first region comprising a fine relief structure and a second region comprising a smooth surface;
A reflective layer covering at least the fine relief structure of the first region;
A display body comprising a fine particle layer on or inside the smooth surface of the second region.   The display body according to claim 1, wherein the light reflecting layer is made of a metal material or a dielectric material.   The display body according to claim 1, wherein at least one optical effect among diffraction, interference, scattering, and absorption is expressed by the fine concavo-convex structure.   The said fine particle layer consists of spherical fine particles with an average particle diameter of 100 nm or more and 1000 nm or less selected from any of organic substances, inorganic substances, and metals, according to any one of claims 1 to 3. Display body.   The fine particle layer is composed of spherical fine particles and a light-transmitting embedding resin that embeds a gap between the spherical fine particles, and a difference in refractive index between the fine particles and the embedding resin is 0.01 or more and 0.80 or less. The display body according to any one of claims 1 to 4, wherein:   6. The display body according to claim 5, wherein in the fine particle layer, most of the fine particle portions are voids.   The display body according to any one of claims 1 to 6 is pasted so as to cover an opening provided in a support body belonging to an article through a light-transmitting adhesive layer formed on a light reflection layer. An article with a display, characterized by The display body according to any one of claims 1 to 6,
A method for determining the authenticity of a display body, comprising: setting a black substrate on the back surface of the display body and visually confirming whether a region corresponding to the fine particle layer exhibits a desired color state. The display body according to any one of claims 1 to 6,
A white substrate is installed on the back surface of the display body, and it is visually confirmed whether or not the region corresponding to the fine particle layer shows a desired color state. Further, a black substrate is installed on the back surface of the display body to correspond to the fine particle layer. A method for determining the authenticity of a display body, characterized by visually confirming whether or not a region shows another desired coloration state and collating whether or not the first and subsequent coloration states have a complementary color relationship.

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