JP2014174327A - Display body and authenticity determination method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display body capable of achieving increased forgery preventing effect.SOLUTION: A display body 100 includes: a structure formation layer 10 formed on one surface side of a light transmissive base material; and a light reflection layer 11 formed in a manner to cover at least a partial region of the structure formation layer 10. The structure formation layer 10 has at least a first region DM1 in which a plurality of projections or recesses are formed and a second region DM2 in which a plurality of projections or recesses are formed. The height or depth of the projections or recesses in the first region DM1 differs from the height or depth of the projections or recesses in the second region DM2, so that the coloration in the first region DM1 and the coloration in the second region DM2 can be visually confirmed as approximately same.

Description

  The present invention relates to a display body using a display technique of color developed by a concavo-convex structure and a method for determining authenticity thereof.

  Articles such as securities, certificates, branded products, electronic devices and personal authentication media are desired to be difficult to counterfeit. Therefore, forgery prevention measures are applied to such articles by attaching or supporting display bodies that are difficult to forge or duplicate.

Conventionally, various display bodies with anti-counterfeit measures have been proposed.
For example, Patent Document 1 proposes a fluorescent image formed article containing two types of phosphors that emit fluorescence having different wavelengths in the visible light region in order to increase the security level of the fluorescent image formed article using fluorescent light emitting ink. Has been.

  In Patent Document 2, a color display surface in which a plurality of basic color elements C (cyan), Y (yellow), and M (magenta) are arranged, and basic color elements C, Y, and M arranged on the color display surface are arranged. There is disclosed a color latent image display which is provided with a color latent image selectively printed with colorless fluorescent ink and can be visually observed as a color image when irradiated with ultraviolet rays.

  Patent Document 3 discloses that an intaglio latent image that can be confirmed only from a specific angle is applied to the intaglio printed matter. Patent Document 4 discloses a combination of a hologram layer, a light reflective layer, and an alignment film. An authenticity determination medium is disclosed.

  In addition, many techniques related to display bodies that have been provided with anti-counterfeit measures have been proposed (Patent Documents 5 to 8).

  Furthermore, in recent years, a medium for authenticity determination provided with a hologram has come to be frequently used. Here, the hologram includes a relief-type hologram formed by a relief-type diffraction grating and a volume-type hologram formed by laser interference exposure, both of which can observe diffracted light shining in rainbow colors. It is a feature.

  As a result of the use of a medium for authenticity determination provided with a hologram, the hologram technology is widely recognized, and the generation of counterfeit products tends to increase. Therefore, there is a problem that a sufficient anti-counterfeit effect cannot be exhibited only by the feature that shines in rainbow color by diffracted light.

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 05-273500 A JP 2008-139508 A

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a display body capable of exhibiting a higher level of forgery prevention effect and a method for determining authenticity thereof.

  In order to solve the above problem, the invention corresponding to claim 1 covers a structure forming layer formed on one surface side of a light-transmitting substrate and at least a part of the region of the structure forming layer. The structure forming layer includes a plurality of light reflecting layers, and the structure forming layer has a plurality of upper surfaces substantially parallel to the flat surface formed on at least a flat surface substantially parallel to the base material surface. A first region in which a plurality of concave portions or a plurality of concave portions having a bottom surface substantially parallel to the flat surface is formed at a specific height or a specific depth, and the plurality of convex portions or the plurality of concave portions A second region formed at a height or depth different from the specific height or depth, and the coloration in the first region and the coloration in the second region are substantially the same. The display body is characterized by being visually checkable.

  That is, the invention corresponding to claim 1 can exhibit a higher level of anti-counterfeiting effect by combining regions having convex structures or regions having concave structures having different structural heights or structural depths.

  According to a second aspect of the present invention, in the display body according to the first aspect of the present invention, a color difference between the first region and the second region is 13 or less.

  According to a third aspect of the present invention, in the display body according to the first or second aspect of the present invention, there is a difference in height between the flat surface and the upper surface of the convex portion or between the flat surface and the bottom surface of the concave portion. It is 150 nm or more and 500 nm or less.

  The invention corresponding to claim 4 is the display body according to any one of claims 1 to 3, wherein the plurality of convex portions or the plurality of concave portions formed in the first region are provided. A ratio between the height difference and the height difference in the plurality of convex portions or the plurality of concave portions formed in the second region is set to be 1.1 or more and 2 or less.

  The invention corresponding to claim 5 is the display body according to any one of claims 1 to 4, wherein the first display area corresponding to the first area and the second display area The second display area corresponding to the area is arranged in a required pattern.

  An invention corresponding to claim 6 is the display body according to any one of claims 1 to 5, wherein a scattering film that scatters visible light on the surface of the display body or A method for determining authenticity of a display body, characterized in that a gray scale pattern can be visually observed from at least the first region and the second region by overlapping scattering plates.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the display body which can exhibit the forgery prevention effect of a higher level.

  According to the invention corresponding to claim 1, a plurality of convex portions or concave portions are formed in the structure forming layer, and a specific color can be visually observed from the display body by applying the light reflecting layer. Become. The specific coloration is different from the feature of rainbow-colored light by the diffracted light of the conventional hologram, and it becomes possible to provide a display body having a higher level of anti-counterfeit effect than the conventional anti-counterfeit technology. . In addition, in each of the first region and the second region, the first region is formed even though the structural height of the plurality of convex portions or the structural depth of the plurality of concave portions is different. And the second region can be provided with substantially the same color.

  According to the invention corresponding to claim 2, when the color difference between the coloration in the first region and the coloration in the second region is 13 or less, the coloration in the first region and the second region Can be provided.

  According to the invention corresponding to claim 3, the structural height of the plurality of convex portions or the structural depth of the plurality of concave portions respectively formed in the first region and the second region is 150 nm or more and 500 nm or less, respectively. As a result, it is possible to provide a display body in which the visible color can be visually observed.

  According to the invention corresponding to claim 4, the ratio of the structural height of the plurality of convex portions or the structural depth of the plurality of concave portions respectively formed in the first region and the second region is 1.1 or more. And the display body from which the coloration of a 1st area | region and a 2nd area | region becomes substantially the same can be provided because it is 2 or less.

  According to the invention corresponding to claim 5, a display body in which a first display area corresponding to the first area and a second display area corresponding to the second area are arranged in a required pattern, In this case, the colors of the plurality of first display areas and the plurality of second display areas arranged are substantially the same, and a required pattern cannot be visually recognized from the display body.

  According to the invention corresponding to claim 6, a gray scale pattern is formed by installing a scattering film or a scattering plate for scattering visible light on the display body according to any one of claims 1 to 5. Can be visually confirmed, and the presence or absence of authenticity of the display body can be easily determined.

Sectional drawing which shows one Embodiment of the display body which concerns on this invention. The perspective view which shows an example of the uneven structure formed in the 1st area | region and 2nd area | region of the structure formation layer which comprises the display body which concerns on this invention. The perspective view which shows the other example of the uneven structure formed in the 1st area | region and 2nd area | region of the structure formation layer which comprises the display body which concerns on this invention. The perspective view which shows the further another example of the uneven structure formed in the 1st area | region and 2nd area | region of the structure formation layer which comprises the display body which concerns on this invention. The perspective view which shows another example of the uneven structure formed in the 1st area | region and 2nd area | region of the structure formation layer which comprises the display body which concerns on this invention. The figure explaining reflection of the light in an uneven structure. The top view which shows other embodiment of the display body which concerns on this invention. The top view when a scattering plate is piled up on the display body of FIG. The graph figure which shows the reflection spectrum of display area DP1 in a display body. The perspective view which shows the random example of arrangement | positioning of the several uneven structure formed in the 3rd area | region of the structure formation layer which comprises the display body which concerns on this invention. The top view which combined the uneven structure formed in the 1st area | region of the structure formation layer which comprises the display body which concerns on this invention, a 2nd area | region, and a 3rd area | region. The top view when a scattering plate is piled up on the display body of FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that, in each drawing, the same reference numerals are assigned to components that perform the same or similar functions, and duplicate descriptions are omitted.

  FIG. 1 is a sectional view showing an embodiment of a display according to the present invention. In FIG. 1, reference numeral 100 denotes a display body provided with forgery prevention means. The 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, and are perpendicular to the main surface. Let the direction be the Z direction.

  The display body 100 includes a structure forming layer 10 and a light reflecting layer 11. The structure forming layer 10 is applied to a substrate such as a light transmissive film.

  A first region DM1 and a second region DM2 are formed on one main surface of the structure forming layer 10. Each of the first region DM1 and the second region DM2 has a fine uneven structure described later.

  The structure forming layer 10 may include a plurality of regions in which a structure different from the fine uneven structure formed in the first region DM1 or the second region DM2 is formed.

  As the material of the structure forming layer 10, for example, a thermoplastic resin, a thermosetting resin, a photocurable resin, or the like can be used.

  The structure forming layer 10 may have a single-layer structure or a multilayer structure as long as it has optical transparency. Moreover, you may be comprised from the material which has optical anisotropy, such as a cholesteric liquid crystal. Furthermore, it may be colored by adding a dye to the resin, or fine particles made of metal, semiconductor, ceramic, magnetic material, or the like may be added.

The material of the structural layer 10, for example, SiO ₂ (silicon dioxide) and TiO ₂ (titanium dioxide), can be used inorganic materials such as MgF ₂ (magnesium fluoride) and mixtures thereof.

  In addition, when making the inorganic material into the structure formation layer 10, it can form by thin film formation techniques, such as vapor deposition and sputtering, for example.

  The light reflecting layer 11 is formed so as to cover at least a part of both the first region DM1 and the second region DM2 formed in the structure forming layer 10. The provision of the light reflecting layer 11 is to facilitate the optical effect described later.

  Incidentally, in the display body 100 shown in FIG. 1, the light reflecting layer 11 is formed so as to cover the entire region of the first region DM1 and the second region DM2.

  Examples of the material of the light reflecting layer 11 include metal materials such as aluminum, nickel, chromium, iron, copper, silver, and gold. The light reflecting layer 11 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 or a mixture thereof, or a dielectric material.

  The light reflecting layer 11 can be formed by, for example, a thin film forming technique such as vapor deposition and sputtering. Furthermore, in order to spatially distribute the light reflecting layer 11, techniques such as mask vapor deposition, chemical etching, and laser processing are used. By spatially distributing the light reflecting layer 11, an image can be expressed using the distribution of the light reflecting layer 11.

  The display body 100 shown in FIG. 1 is provided so that the light reflection layer 11 is positioned on the front side of the structure forming layer 10 as an example, but may be provided on the rear side of the structure forming layer 10.

  Next, several examples of the uneven structure formed in the first region DM1 and the second region DM2 of the structure forming layer 10 will be described.

  FIG. 2 is a perspective view showing an example of the concavo-convex structure of the first region DM1 and the second region DM2.

  In the display body 100, a concave structure 20 is formed in the first region DM1, and a concave structure 21 is formed in the second region DM2. The concave structure 20 has a quadrangular prism shape, and the structure depth is H1. The concave structure 21 similarly has a quadrangular prism shape, and its structural depth is H2. These recess structures 20 and 21 are all arranged in a two-dimensional lattice pattern in the XY plane.

  FIG. 3 is a perspective view showing another example of the uneven structure of the first region DM1 and the second region DM2. As is apparent from FIG. 3, the recess structure 20 in the first region DM1 has a quadrangular prism shape, while the other second region DM2 has a recess structure 22 having a cylindrical shape.

  FIG. 4 is a perspective view showing still another example of the uneven structure of the first region DM1 and the second region DM2. As is apparent from FIG. 4, a concave structure 20 having a quadrangular prism shape is formed in the first region DM1, while a convex structure 23 is formed in the other second region DM2. The convex structure 23 has a quadrangular prism shape, and its structural height is H3.

  Further, FIG. 5 is a perspective view showing still another example of the uneven structure of the first region DM1 and the second region DM2. The concave structure 20 in the first region DM1 and the concave structure 21 in the second region DM2 have a quadrangular prism shape as in FIG. 2, but the concave structure 20 and the concave structure 21 are both XY planes. Are randomly arranged within.

  Next, a detailed configuration and optical effect of the display body 100 will be described.

  The structure forming layer 10 of the display body 100 shown in FIGS. 1 to 5 is configured to include the first region DM1 and the second region DM2 as described above.

  In the first region DM1, the recessed portion structure 20 has a structure depth H1, and a specific color can be visually confirmed accordingly. On the other hand, in the second region DM2, a concave structure 21 having a structural depth H2 is formed. Therefore, a specific color can be visually confirmed even in the second region DM2.

  Therefore, as the concave structure 20 of the first region DM1 and the concave structure 21 of the second region DM2, the coloration in the first region DM1 and the coloration in the second region DM2 are substantially the same by visual observation. Formed as follows.

  Also in the display body 100 of FIGS. 2, 3, 4, and 5, the first region DM <b> 1 and the second region DM <b> 2 are configured by any two combinations of the concave structures 20, 21, 22 and the convex structure 23. Is done. Therefore, the specific coloration can be visually confirmed in the first region DM1 as in the above, and the specific coloration can be visually confirmed in the second region DM2. Further, the concave structures 20, 21, 22 and the convex structure 23 are formed so that the coloration in the first region DM1 and the second region DM2 is substantially the same by visual confirmation.

  Next, an optical effect obtained by the concave structures 20, 21, and 22 having a specific structural depth and the convex structure 23 having a specific structural height will be described with reference to FIG.

  FIG. 6 shows a state in which a concave structure having a structure depth H is formed in a partial region of the medium interface having refractive indexes n1 and n2 and light rays P1 and P2 are incident on the concave structure in parallel. It is a figure showing.

Here, the light ray P1 is reflected at the medium interface, and the light ray P2 is reflected at the bottom surface of the concave structure having the structure depth H. Therefore, the following optical path length difference L occurs between the light rays P1 and P2.
L = H / (n1 · cos θ) (1)
However, (theta) is the incident angle of the light rays P1 and P2.

As a result, due to the optical path length difference L obtained from the equation (1), interference occurs when the phase of the light beam P1 and the light beam P2 changes, and light of a specific wavelength intensifies or weakens depending on the interference condition. A relationship is established.
mλ = L (Constructive interference condition) (2a)
(M + 1/2) λ = L (interfering interference condition) (2b)
m is the order and λ is the incident wavelength.

  Therefore, it can be seen from the equations (1) to (2a) and (2b) that the wavelength λ at which interference occurs is proportional to the structural depth H and inversely proportional to the refractive index n1. Therefore, the wavelength λ to be interfered can be freely changed by adjusting the structure depth H and the refractive index n1.

Therefore, in order to cause interference of light in the visible light region, a structural depth or a structural height that satisfies the following formulas (3a) and (3b) is required.
H = mλ · n1 · cos θ (intensifying interference condition) (3a)
H = (m + 1/2) λ · n1 · cos θ (weakening interference condition) (3b)
That is, from the equation (3a), when m = 1, n1 = 1.5, θ = 45 degrees and the wavelength λ is changed from 300 to 600 nm (visible light region) in the constructive interference condition, H is 318 to It becomes 636 nm. Further, from the equation (3b), when m = 0, n1 = 1.5, θ = 45 degrees and the wavelength λ is changed from 300 to 600 nm under the destructive interference condition, H becomes 159 to 318 nm.

  Therefore, by setting the structural height of the convex structure or the structural depth of the concave structure formed in the structure forming layer 10 to 150 nm or more and 500 nm or less, light interference occurs in the visible light region, and coloration by visual observation occurs. Changes can be confirmed.

  1 and 2, a concave structure 20 having a structural depth H1 is formed in the first region DM1, and a concave structure 21 having a structural depth H2 is formed in the second region DM2. Due to the difference between the structural depths H1 and H2, the above-described light interference occurs, and specific wavelengths are strengthened or weakened to cause coloration in the first region DM1 and the second region DM2. At that time, by setting the ratio between the structural depth H1 and the structural depth H2 to be between 1.1 and 2, interference of a specific wavelength λ occurs in the formulas (3a) and (3b). .

  If the ratio between the structural depth H1 and the structural depth H2 is 2 or more, either of the structural depths H1 and H2 exceeds 1 μm, thereby increasing the component of light scattered by the wall surface of the concave structure. However, the color becomes low saturation.

  Further, since the interference wavelength is changed not only by the structural depth but also by changing the refractive index n1 from the equations (3) and (3 ′), the upper portion of the light reflecting layer 11 in the first region DM1 and the first By installing a different medium above the light reflecting layer 11 in the second region DM2, it is possible to obtain an equivalent effect.

  The light interference does not occur because the concave structures 20 and 21 have a quadrangular prism shape, and the bottom surfaces of the concave structures 20 and 21 are substantially parallel to the interface of the structure forming layer 10 or the light reflecting layer 11. Caused by Therefore, as shown in FIG. 3, the concave structure 22 may be cylindrical.

  Furthermore, even when the concave structures 21 and 23 (see FIGS. 2 and 3) of the second region DM2 are the convex structures 23 as shown in FIG. 4, the top surface of the convex structures 23 and the structure forming layer 10 Alternatively, when the interface with the light reflecting layer 11 is substantially parallel, light interference occurs, and it is possible to visually observe that coloration has occurred in the second region DM2.

  2, 3, and 4, the concave structures 20, 21, and 22 and the convex structure 23 are two-dimensionally arranged in a square lattice pattern on the XY plane. In some cases, the effect of the diffraction grating is obtained, and a rainbow-colored color may be seen during visual observation.

  Thus, in order to avoid the rainbow color, it is necessary to randomly arrange the concave structure 20 and the concave structure 21 in each of the first region DM1 and the second region DM2 as shown in FIG. is there.

  Here, the concave structures 20, 21, 22 and the convex structure 23 are formed by forming a master using a well-known fine processing technique such as photolithography, electron beam drawing, laser drawing, laser cutting, or the like. It is formed by embossing the formation layer 10.

When quantitatively evaluating the coloration of the first region DM1 and the second region DM2, it is necessary to consider the color difference ΔE * ab defined by the following formula (4).
ΔE * ab = ((ΔL *) ² + (Δa *) ² + (Δb *) ² ) ^1/2 (4)
This color difference ΔE * ab is obtained when the L * a * b * color system is used, and may differ depending on the color system used for evaluation. Here, L * is a value indicating brightness, a * and b * are values indicating hue, ΔL * is a difference of L * between two colors, and Δa * and Δb * are a * and b * between two colors, respectively. The difference is shown.

  Therefore, if the value of the color difference ΔE * ab is small, the two colors are substantially the same during visual observation, and the two colors can be recognized as different colors during visual observation as the color difference increases. If the value of the color difference ΔE * ab is 13 or less, the impression is that the two colors exhibit substantially the same color tone. Further, if the color difference ΔE * ab is 6 or less, the impression is that the two colors have substantially the same color tone.

  FIG. 7 shows the display body 100 ′ when the display area DP1 corresponding to the first area DM1 and the display area DP2 corresponding to the second area DM2 are arranged in a character pattern. Under normal light sources, the colors of the display areas DP1 and DP2 are substantially the same during visual observation, so the observer cannot recognize that a character pattern is formed on the display body 100 ′. Here, the normal light source includes all of what is generally called a light source, such as a light source using a fluorescent lamp, a light source using an LED (light emitting diode), and a light source using sunlight.

  Next, FIG. 8 is a diagram showing a state in which the scattering plate 200 is overlaid on the display body 100 ′ of FIG. By overlapping the scattering plate 200 on the display body 100 ′, the gray scale values of the display area DP1 and the display area DP2 are different, and the character pattern “OK” can be visually confirmed in a clear state. Here, the reason why the gray scale values are different is that the structure depth or height of the concave structure or the convex structure formed in the display region DP1 and the display region DP2 is different.

  Thus, by overlapping the scattering plate 200 on the display body 100 ′, the gray scale pattern can be visually observed, and it can be determined that the display body 100 ′ is genuine.

  FIG. 9 is a graph showing the reflection spectrum of the display region DP1 in the display body 100. FIG.

  In FIG. 9, the reflection spectrum (reflectance) of the display region DP1 in the display body 100 when there is no scattering plate 200 is indicated by a solid line, and the reflection spectrum (reflection) of the display region DP1 in the display body 100 ′ when the scattering plate 200 is present. Rate) is indicated by a dotted line.

  As is clear from these two reflection spectra, it can be seen that the color of the display region DP1 disappears and becomes gray scale by overlapping the scattering plate 200 on the display body 100 '.

  FIG. 10 is a perspective view showing another example of the concavo-convex structure formed on the display body 100.

  This display body 100 shows an example in which the concave structure 20 and the concave structure 21 are randomly arranged in the third region DM3. Even when the recessed structures 20 and 21 are randomly arranged, the coloration that can be visually observed in the third region DM3 is substantially the same as the coloration in the first region DM1 and the second region DM2 described above.

  FIG. 11 is a plan view showing a display body 100 ′ in which the display area DP 3 by the third area DM 3 is included in the display areas DP 1 and DP 2.

  Since the display body 100 'has substantially the same coloration in the display areas DP1, DP2, and DP3, it is not known whether a character pattern is formed on the display body 100' during visual observation under a normal light source.

  FIG. 12 is a view showing a state in which the scattering plate 200 is overlaid on the display body 100 ′ of FIG.

  In the display body 100 ', the display area DP1 is colored near white, the display area DP2 is colored near black, and the display area DP3 is colored near gray. That is, as shown in FIG. 10, since the concave structures 20 and 21 are randomly arranged in the third region DM3, the gray scale value can be changed when the scattering plates 200 are overlapped. .

  Therefore, it is possible to form a gray scale image by patterning the display areas DP1, DP2, DP3 and overlapping the scattering plate 200 on the display body 100 ′.

  11 and 12, three display areas DP1, DP2, and DP3 are shown. However, a larger number of display areas may be used, and the display body 100 ′ may be configured with at least two areas. That's fine.

  As described above, the display body 100 ′ having a plurality of display areas shows substantially the same color under a normal light source, and therefore, the pattern shape cannot be visually observed. The pattern shape can be visually confirmed as a scale pattern. Since the pattern shape can be visually confirmed by using the scattering plate 200 in this manner, the forgery prevention effect can be enhanced.

  In this way, the means for determining authenticity using a scattering plate or film that scatters visible light significantly reduces costs compared to conventional means for determining authenticity using a polarizing plate or polarizing film. Is possible. Actually, in addition to using a scattering plate or a scattering film, it is possible to visually check the pattern shape of the gray scale pattern by using thin paper or tracing paper. It becomes possible.

  Further, the color obtained by the interference by the concave structure or the convex structure has a metallic luster different from that of ordinary printing ink. Further, since the interference is not caused by the concave structure or the convex structure by increasing the observation angle, there is a feature that the coloring is eliminated. As a result, counterfeiting by a normal printing technique becomes difficult, and a more advanced forgery prevention effect can be achieved.

  Furthermore, since the concave structure or the convex structure is a fine concavo-convex structure, forgery is difficult. In addition, in order to measure the difference in structure depth or structure height, it cannot be judged only by measurement with an optical microscope etc. from the upper surface of the structure, and it is difficult to forge because the cross section of the structure must be observed .

  The display body 100 ′ in the embodiment as described above can be used, for example, by being attached to a printed material, a card medium, or another article as an anti-counterfeit label via an adhesive or the like. Furthermore, it can be used for purposes other than prevention of counterfeiting, for example, the display body 100 ′ can be used as a toy, a learning material, or an ornament.

  Hereinafter, although the specific Example of the display body which concerns on this invention is described, this invention is not limited to this Example.

  In Example 1, an ultraviolet curable resin corresponding to the structure forming layer 10 was applied to a PET (polyethylene terephthalate) film with a gravure roll coater to obtain an uneven structure forming film.

  Next, in order to form a concave structure in the structure forming layer 10, a region where the concave structure is randomly arranged so as to be 300 nm square at a structure depth of 250 nm, and a random so as to be 300 nm square at a structure depth of 430 nm. A metal plate was produced by patterning two regions of the region where the concave structure was arranged in a lattice pattern.

  Thereafter, the ultraviolet curable resin was pressed against the metal plate, irradiated with ultraviolet rays from a metal halide lamp, and after the ultraviolet curable resin was cured, the metal plate was peeled to form the recessed structures 20 and 21. Thereafter, aluminum was deposited on the recess structures 20 and 21 by a vacuum deposition method so as to have a film thickness of about 50 nm, thereby forming the light reflecting layer 11.

  In the display body formed with the recessed structures 20 and 21 having different structure depths obtained as described above, it can be visually confirmed that two areas having different color structure depths are colored in green. It was.

  Then, when the scattering plate 200 was superimposed on the display body obtained as described above, the gray scale pattern patterned in a lattice shape could be visually confirmed.

  In the same manner as in Example 1, an ultraviolet curable resin corresponding to the structure forming layer 10 was applied to a PET film with a gravure roll coater to obtain an uneven structure forming film.

  Next, in order to form a concave structure in the structure forming layer 10, a region where the concave structure is randomly arranged so as to be 300 nm square at a structure depth of 300 nm, and a random that is 400 nm square at a structure depth of 450 nm. A metal plate was produced by patterning two regions of the region where the concave structure was arranged in a lattice pattern.

  Thereafter, the ultraviolet curable resin was pressed against the metal plate, irradiated with ultraviolet rays from a metal halide lamp, and after the ultraviolet curable resin was cured, the metal plate was peeled to form the recessed structures 20 and 21. Thereafter, aluminum was deposited on the recess structures 20 and 21 by a vacuum deposition method so as to have a film thickness of about 50 nm, thereby forming the light reflecting layer 11.

  In the display body formed with the recessed structures 20 and 21 having different structure depths obtained as described above, it can be visually confirmed that magenta is colored in two regions having different color structure depths. It was.

  Further, when the scattering plate 200 was superimposed on the obtained display body, the gray scale pattern patterned in a lattice shape could be visually confirmed.

  In addition, the said embodiment and Example are shown as an example and are not intending limiting the range of invention. The above embodiments and examples can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and examples are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 10 ... Structure formation layer, 11 ... Light reflection layer, 20, 21, 22 ... Concave structure, 23 ... Convex structure, 100, 100 '... Display body, 200 ... Scattering plate, H, H1, H2 ... Structure depth, H3: Structural height, DM1: First region, DM2: Second region, DM3: Third region, P1, P2: Light, L: Optical path length difference, n1, n2: Refractive index, DP1, DP2, DP3 ... display area.

Claims (6)

A display body comprising a structure forming layer formed on one surface side of a light-transmitting substrate and a light reflecting layer formed to cover at least a part of the structure forming layer. ,
The structure forming layer includes at least a plurality of convex portions having a top surface substantially parallel to the flat surface formed on a flat surface substantially parallel to the base material surface or a plurality of concave portions having a bottom surface substantially parallel to the flat surface. Are formed at a specific height or a specific depth, and the plurality of convex portions or the plurality of concave portions are formed at a height or depth different from the specific height or depth. A second region being provided, and
The display body characterized in that the coloration in the first region and the coloration in the second region are substantially the same and can be visually confirmed.   The display body according to claim 1, wherein a color difference between the first region and the second region is 13 or less.   In the plurality of convex portions or the plurality of concave portions formed in the first region and the second region, a height difference between the flat surface and the upper surface of the convex portion or between the flat surface and the bottom surface of the concave portion is 150 nm. The display body according to claim 1, wherein the display body has a thickness of 500 nm or less.   A ratio between the height difference in the plurality of convex portions or the plurality of concave portions formed in the first region and the height difference in the plurality of convex portions or the plurality of concave portions formed in the second region is 1. The display body according to any one of claims 1 to 3, wherein the display body is set between 1 and 2.   5. The display area corresponding to the first area and the display area corresponding to the second area are arranged in a required pattern. 6. Display body. A display body according to any one of claims 1 to 5,
A display in which a gray scale pattern can be visually confirmed at least from the first region and the second region by overlapping a scattering film or a scattering plate that scatters visible light on the surface of the display body. Body authenticity determination method.

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