JP2010078821A - Display body, adhesive label, and labeled article - Google Patents

Abstract

A display body capable of realizing a higher anti-counterfeit effect and a special visual effect is provided.
In the display body 10 of the present invention, a plurality of recesses or projections are arranged one-dimensionally or two-dimensionally, and the distance between the centers of the plurality of recesses or projections is in the range of 200 nm to 500 nm. A light transmissive layer including the concavo-convex structure region on one main surface, a reflective layer supported on the one main surface and covering at least a part of the concavo-convex structure region, and the reflective layer on the one main surface And a refractive layer having a refractive index of 0.2 or more different from the refractive index of the reflective layer.
[Selection] Figure 1

Description

  The present invention relates to a display technique that provides, for example, an anti-counterfeit effect.

  It is desirable that authentication items such as cash cards, credit cards and passports, and securities such as gift certificates and stock certificates are difficult to counterfeit. Therefore, conventionally, a label that is difficult to counterfeit or counterfeit and is easy to distinguish from counterfeit or counterfeit is attached to such articles in order to prevent counterfeiting. Such a label is described in Patent Document 1, for example.

  In recent years, the distribution of counterfeit products has been regarded as a problem for items other than certified items and securities. Therefore, the opportunity to apply the above-described anti-counterfeiting technology with respect to certified articles and securities is increasing.

By the way, many display bodies used as anti-counterfeit labels have a problem that it is relatively easy for an observer to apply anti-counterfeiting technology. If the application of the anti-counterfeit technology is realized, there is a high possibility that the display body is illegally copied or altered. That is, an excellent anti-counterfeit effect cannot be achieved. Here, the fact that counterfeiting or counterfeiting is difficult, and the fact that it is easy to distinguish from counterfeiting or counterfeiting are called anti-counterfeiting effects.
JP 2005-91699 A

  The objective of this invention is providing the display body which can implement | achieve the higher forgery prevention effect and a special visual effect.

According to the first aspect of the present invention, the plurality of recesses or projections are arranged one-dimensionally or two-dimensionally, and the distance between the centers of the plurality of recesses or projections is in the range of 200 nm to 500 nm. A light transmissive layer including the concavo-convex structure region in one main surface;
A reflective layer supported on the one main surface and covering at least a part of the concavo-convex structure region;
A refractive layer that is supported so as to cover the reflective layer on the one main surface and has a refractive index of 0.2 or more from the refractive index of the reflective layer;
It is a display body characterized by comprising.

  The invention according to claim 2 of the present invention is the display body according to claim 1, wherein a difference in refractive index between the reflective layer and the refractive layer is 0.5 or more.

  The invention according to claim 3 of the present invention is characterized in that the refractive layer is made of a metal compound, and the refractive index of the metal compound is 0.5 or more higher than the refractive index of the reflective layer. 2. The display body according to 2.

The invention according to claim 4 of the present invention includes a plurality of the uneven structure regions,
The shape, depth or height, center-to-center distance, and arrangement pattern of the plurality of recesses or projections in at least one of the uneven structure regions are different from those in other uneven structure regions. The display body according to any one of the above.

  According to a fifth aspect of the present invention, there is provided an adhesive label comprising the display body according to any one of the first to fourth aspects and an adhesive layer provided on the display body. It is.

  The invention according to claim 6 of the present invention is a labeled article comprising the display body according to any one of claims 1 to 4 and an article supporting the display.

  According to the present invention, it is possible to achieve a higher anti-counterfeit effect and a special visual effect.

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

  FIG. 1 is a plan view schematically showing a display body according to one aspect of the present invention. 2 is a cross-sectional view taken along the line II-II of the display shown in FIG. In addition, in the display body 10 of FIG.1 and 2, the mode observed from the light transmissive layer 11 side is shown.

The display body 10 includes a light transmission layer 11, a reflection layer 13, and a refraction layer 14, and in the example shown in FIG. 2, an uneven structure region 12a and a non-relief structure are formed on one main surface of the light transmission layer 11. And a structural region 12b. As will be described later, the concavo-convex structure region 12a is provided with a plurality of concave portions or convex portions. The plurality of concave portions or convex portions emit diffracted light in a specific direction when irradiated with light. Further, the non-relief structure region 12b is a flat surface.
Further, a reflective layer 13 is formed on the main surface of the light transmissive layer 11 including the concavo-convex structure region 12 a so as to cover at least a part of the concavo-convex structure region 12 a, and the light transmissive layer is covered so as to cover the reflective layer 13. A refractive layer 14 is formed on the main surface 11. Hereinafter, the light transmission layer 11 side is referred to as “front surface”, and the refractive layer 14 side is referred to as “back surface”.

Next, a structure that can be used for the uneven structure region 12a will be described. As described above, the concave-convex structure region 12a is provided with a plurality of concave portions or convex portions.
As described above, the non-relief structure region 12b is a flat surface. Further, the non-relief structure region 12b can be omitted.

FIG. 3 is an enlarged perspective view showing an example of a structure that can be employed in the concavo-convex structure region 12a of the display body 10 shown in FIGS. In the example shown in FIG. 3, the recesses or projections RP are two-dimensionally arranged.
The concave portions or the convex portions RP arranged in the concavo-convex structure region 12a are regularly arranged within a range of a center-to-center distance of 200 nm to 500 nm. Therefore, as will be described in detail later, the concavo-convex structure region 12a can emit diffracted light only in a specific direction and angle when irradiated with illumination light.

  The arrangement of the plurality of concave portions or convex portions RP is, for example, a square lattice, a rectangular lattice, or a triangular lattice. By controlling the arrangement of the concave portions or the convex portions RP, it is possible to arbitrarily adjust the emission angle and the emission direction of the diffracted light emitted from the concavo-convex structure region 12a. As an example, FIG. 3 illustrates a case where a plurality of convex portions are two-dimensionally arranged in the X direction and the Y direction orthogonal to each other to form a square lattice.

In addition, each of the concave portion or the convex portion RP can have various shapes.
Each of the recesses or projections RP preferably has a forward tapered shape such as a pyramid, a cone, and a semi-spindle shape. By having the forward taper shape, when the concavo-convex structure region 12a is observed from the normal direction, the reflectance of the regular reflection light of the concavo-convex structure region 12a can be further reduced.

FIG. 4 is an enlarged perspective view showing another example of a structure that can be adopted in the uneven structure region 12a of the display body shown in FIGS. In the example shown in FIG. 4, the concave portion or the convex portion RP is a relief type diffraction grating in which a plurality of grooves are arranged one-dimensionally.
In this case, by controlling the lattice constant, orientation, depth, and the like of the plurality of grooves, it is possible to arbitrarily adjust the emission angle and the emission direction of the diffracted light emitted from the concavo-convex structure region 12a. .

  The term “diffraction grating” means a structure that generates a diffracted wave when irradiated with illumination light such as natural light, and is recorded on a hologram in addition to a normal diffraction grating in which a plurality of grooves are arranged in parallel and at equal intervals. Interference fringes are also included.

  The concave portion or the convex portion RP is arranged with a center-to-center distance of 200 nm to 500 nm. In this case, as will be described later, it is relatively easy to distinguish between a genuine product and a non-genuine product by visually recognizing or detecting diffracted light emitted from the uneven structure region 12a.

  Further, the depth or height of the concave portion or the convex portion RP is set to be substantially constant in order to suppress light scattering. The depth or height of the concave portion or convex portion RP is typically 100 nm or more.

  The image displayed on the display body 10 may be composed of a plurality of pixels arranged two-dimensionally. In this case, a relatively complex image can be displayed by making at least one of the shape, depth or height, center-to-center distance, and arrangement pattern of the concave portion or the convex portion RP different between these pixels. .

  The concave portion or convex portion RP can be formed, for example, by pressing a mold provided with fine convex portions or concave portions against the resin. For example, the concave portion or the convex portion RP is obtained by a method in which the original plate provided with the convex portion or the concave portion is pressed against a thermoplastic resin layer provided on the base material while applying heat, that is, a hot embossing method. It is done. Alternatively, the concave portion or the convex portion RP is formed by applying an ultraviolet curable resin on the substrate, irradiating the ultraviolet ray from the substrate side while pressing the original plate on the substrate, curing the ultraviolet curable resin, and then removing the original plate. It is also possible to form.

  This original plate is manufactured using, for example, an electron beam drawing apparatus. Usually, a reverse plate is manufactured by transferring the concavo-convex structure of the original plate, and a duplicate plate is manufactured by transferring the concavo-convex structure of the reverse plate. Then, if necessary, a reversal plate is manufactured using the copy plate as an original plate, and the uneven structure of the reversal plate is transferred to further manufacture a copy plate. In actual production, a copy obtained in this way is usually used.

As a material of the light transmission layer 11, for example, a transparent material can be used.
In addition, the light transmission layer 11 may have a single layer structure or a multilayer structure. For example, plastic materials such as polyethylene terephthalate (PET) and polycarbonate are used as the material of the previous substrate, and acrylic resin, polycarbonate resin, styrene resin, acrylic / polyethylene resin as the previous thermoplastic resin or ultraviolet curable resin. A styrene copolymer resin may be used. Alternatively, an inorganic material containing silicate may be used.

  The reflective layer 13 covers the whole or part of the main surface provided with the concave structure and / or the convex structure of the light transmission layer 11.

  As the reflection layer 13, for example, aluminum (1.48), silver (0.17), gold (0.34), platinum (2.9), iron (2.36), chromium (2.4), Layers of metallic materials such as zinc (2.4) and their alloys can be used. The numbers in the parentheses indicate the refractive index of each metal material.

The reflective layer 13 can be formed by, for example, a vapor deposition method. For example, it can be formed by oblique vapor deposition or oblique sputtering.
In addition, by coating the reflective layer 13 only on a part of the concavo-convex structure region 12a, it is possible to impart a design that is different from the case where the reflective layer 13 is entirely covered.

  Examples of the refractive layer 14 include aluminum (1.48), silver (0.17), gold (0.34), platinum (2.9), iron (2.36), chromium (2.4), Metal materials such as zinc (2.4) and alloys thereof, zinc sulfide (2.37), titanium oxide (2.52), copper oxide (2.71), silver chloride (2.05), zinc oxide (1.95), chromium oxide (2.5), zirconium oxide (2.4), aluminum oxide (1.76), ferric oxide (3.01), ferric trioxide (3.08), A layer made of a metal compound such as mercury sulfide (2.95) can be used. In addition, the number in the said parenthesis shows the refractive index of each material.

  The refractive layer 14 can be formed by, for example, a vapor deposition method such as a vacuum evaporation method or a sputtering method.

  The display body 10 displays the image demonstrated below, for example, when the front surface is illuminated with white light.

  In the concavo-convex structure region 12a, the interface between the light transmission layer 11 and the reflective layer 13 includes fine concave portions or convex portions RP arranged two-dimensionally. Therefore, most of the light incident on the concavo-convex structure region 12 a is reflected a plurality of times at the interface between the light transmission layer 11 and the reflection layer 13. As a result, most of the incident light is absorbed, and the concavo-convex structure region 12a does not emit reflected light or emits weak reflected light in a direction perpendicular to the display surface.

  Since the center-to-center distance of the concave portion or the convex portion RP is in the range of 200 nm to 500 nm, no diffracted light is emitted in the direction perpendicular to the display surface, or is emitted in the direction perpendicular to the display surface. The diffracted light is only light with a low visibility. Therefore, black or gray is displayed in the uneven structure region 12a.

In the non-relief structure region 12b, the interface between the light transmission layer 11 and the reflection layer 13 is flat.
Therefore, when the regular reflection light can be observed, the non-concave structure region 12b displays white as the light source color.

  Therefore, when viewed from a direction perpendicular to the display surface, the display body 10 looks like a printed pattern in which the concavo-convex structure region 12a is formed using black ink, and the non-concave structure region 12b appears white.

  Next, the visual effect of the display body 10 caused by the uneven structure region 12a will be further described.

  FIG. 5 is a diagram schematically showing how the concavo-convex structure region 12a emits diffracted light. In FIG. 5, L1 indicates illumination light, L2 indicates regular reflection light or zero-order diffracted light, and L3 indicates first-order diffracted light.

  In the concavo-convex structure region 12a, the concave portions or the convex portions RP are regularly arranged. Therefore, when the concavo-convex structure region 12a is illuminated, strong diffracted light is emitted in a specific direction with respect to the traveling direction of the illumination light that is incident light.

  The most representative diffracted light is first-order diffracted light. The second-order or higher-order diffracted light has a significantly lower intensity than the first-order diffracted light. For this reason, the influence of higher-order diffracted light on visual recognition and detection is negligible.

The emission angle β of the first-order diffracted light can be calculated from the following equation (1) when the light travels in a plane parallel to the normal line N of the concavo-convex structure region 12a.
d = λ / (sin α−sin β) (1)
In this formula (1), d represents the distance between the centers of the concave or convex portions RP, and λ represents the wavelengths of incident light and diffracted light. Α represents the exit angle of 0th-order diffracted light, that is, transmitted light or specularly reflected light.

  The angles α and β define a clockwise direction from the normal N as a positive direction. An angle range of −90 ° to 0 ° with respect to the normal N is referred to as a “negative angle range”, and an angle range of 0 ° to 90 ° is referred to as a “positive angle range”. Further, it is assumed that the emission angle α belongs to a positive angle range. That is, it is assumed that 0 ° <α <90 °.

  As is clear from the equation (1), the emission angle β of the first-order diffracted light changes according to the wavelength λ. That is, the concave portion or the convex portion RP has a function as a spectroscope. Therefore, when the illumination light is white light, when the observation angle is changed in a plane parallel to the normal line N, the color visually recognized by the observer changes.

  As can be seen from the equation (1), when the center-to-center distance d is smaller than the wavelength λ of the incident light, the emission angle β can be a negative value with respect to an arbitrary incident angle −α. That is, in this case, when the incident light L1 belongs to the negative angle range, the first-order diffracted light L3 also belongs to the negative angle range. Therefore, the concavo-convex structure region 12a does not emit the first-order diffracted light having a visible light wavelength in a positive angle range, or the first-order diffracted light emitted in this angle range can be only light having a wavelength with low visibility.

  The display 10 of the present invention is observed under general illumination light (white light), and “general illumination light” refers to visible light having a wavelength of about 380 nm to about 780 nm. is there.

As described above, since the concave-convex structure region 12a of the display body 10 has a distance between the centers of the concave portions or convex portions within the range of 200 nm to 500 nm, printing formed using black ink when observed from the normal direction. It looks like a pattern and appears colored when observed from a certain oblique direction. Such a color change cannot be reproduced with a normal diffraction grating or hologram.
Note that the case where the distance between the centers of the concave portions or the convex portions is less than 200 nm is excluded because the first-order diffracted light is not emitted under general illumination light.

  In addition, since the concave portion or the convex portion RP is fine, it is difficult for those who perform fraud to analyze their structures. And even if those structures can be analyzed, it is extremely difficult to reproduce this fine structure. That is, the display body 10 is difficult to counterfeit and provides a special visual effect.

  Next, the effect of providing the refractive layer 14 on the back surface of the reflective layer 13 will be described.

  In the display body 10, the above-described visual effect can be provided only by providing the reflective layer 13 on the back surface of the light transmission layer 11.

However, in order to emphasize black color when observed from a direction perpendicular to the display surface (specifically, to suppress the lightness (L * value) of black), the reflectance at the interface between the light transmission layer 11 and the reflection layer 13 is set as much as possible. The output intensity of coloring (diffracted light) when observed from an oblique direction must be sacrificed to some extent. Conversely, in order to increase the output intensity of diffracted light, the lightness (L * value) of black in the vertical direction must be slightly increased.
That is, it is difficult to highlight both black when observed from a direction perpendicular to the display surface and coloring (diffracted light) when observed from an oblique direction.

  In the display body 10, for example, when an Al layer (refractive index is 1.48) is provided on the back surface of the light transmission layer 11 as the reflection layer 13, the back surface of the display body 10 including the light transmission layer 11 and the reflection layer 13 is provided. The difference in refractive index from an air layer (with a refractive index of 1) is about 0.5. By increasing this difference in refractive index, the intensity of diffracted light can be slightly increased while maintaining the blackness in the vertical direction.

  In addition, the display body 10 including the light transmission layer 11 and the reflection layer 13 is generally configured so that an adhesive layer, a resin layer, and the like are further laminated on the back surface of the reflection layer 13 from the viewpoint of antifouling, resistance, and forgery prevention. It is possible that A typical adhesive layer and resin layer have a refractive index of about 1.5, and in such a configuration, the refractive index difference between the reflective layer 13 and the back layer thereof is smaller than when an air layer is present on the back surface. Thus, the intensity of the diffracted light is further reduced.

In the display body 10 according to the present invention, a refractive layer 14 having a refractive index having a difference of 0.2 or more from the refractive index of the reflective layer 13 is provided on the back surface of the reflective layer 13. When the difference in refractive index is less than 0.2, the reflectance at the interface between the reflective layer and the back surface of the reflective layer is lowered, and the diffracted light intensity is lowered. Therefore, by setting the refractive index difference to be 0.2 or more, it is possible to prevent the diffraction intensity from being lowered and to further enhance the visual effect described above.
Further, it is more preferable that the difference in refractive index is 0.5 or more because the diffraction intensity is further increased.

  Further, it is effective for antifouling and resistance, and furthermore, the refraction layer 14 can prevent the surface of the reflection layer 13 from being exposed. Can be difficult.

FIG. 6 is a cross-sectional view schematically showing an adhesive label according to one embodiment of the present invention.
The adhesive label 20 includes a display body 10 and an adhesive layer 21 provided on the display body 10.
FIG. 6 shows, as an example, a case where the adhesive layer 21 is provided on the back surface (on the refractive layer 14 surface) of the display body 10 shown in FIG.

When the adhesive layer 21 is provided, the surface of the refractive layer 14 can be prevented from being exposed. Therefore, by using the display body 10 as a part of the pressure-sensitive adhesive label 20, it is possible to make it more difficult to duplicate the concave portion or the convex portion at the previous interface.
In the display 10, the adhesive layer 21 is formed on the light transmitting layer 11 when the light transmitting layer 11 side is the back side and the refractive layer 13 b side is the front side.

For example, the adhesive label 20 is attached to an article whose authenticity is to be confirmed, or is attached to another article such as a base material of a tag to be attached to the article. Thereby, the forgery prevention effect can be provided to the said article | item.
Note that the adhesive label 20 can be provided with an anti-replacement function by cutting the reflective layer 13 and the refractive layer 14 or further providing a brittle layer between the display 10 and the adhesive layer 21. . Thereby, the further superior forgery prevention effect can be achieved.

FIG. 7 is a plan view schematically showing an example of a labeled article.
FIG. 7 shows a printed matter 30 as an example of an article with a display body. The printed material 30 is an ID (identification) card and includes a base material 31. The base material 31 is made of plastic, for example. A concave portion is provided on one main surface of the substrate 31, and the IC chip 32 is fitted in the concave portion. Electrodes are provided on the surface of the IC chip 32, and information can be written to the IC and / or information recorded on the IC via these electrodes. A printed layer 40 is formed on the substrate 31. The display body 10 mentioned above is being fixed to the surface in which the printing layer 40 of the base material 31 was formed, for example through the adhesion layer. The display body 10 is prepared as an adhesive sticker or a transfer foil, for example, and is fixed to the base material 31 by sticking it to the printing layer 40.

  The printed material 30 includes the display body 10 described above. Therefore, forgery and imitation of this printed matter 30 is impossible or difficult. Moreover, since the printed matter 30 further includes the IC chip 32 and the printed layer 40 in addition to the display body 10, it is possible to adopt a forgery prevention measure using them.

  In FIG. 7, an ID card is illustrated as a printed material including the display body 10, but the printed material including the display body 10 is not limited thereto. For example, the printed matter including the display body 10 may be other cards such as a magnetic card, a wireless card, and an IC (integrated circuit) card. Alternatively, the printed matter including the display body 10 may be securities such as gift certificates and stock certificates. Alternatively, the printed matter including the display body 10 may be a tag to be attached to an article to be confirmed as a genuine product. Alternatively, the printed matter including the display body 10 may be a package body that contains an article to be confirmed to be genuine or a part thereof.

  Moreover, in the printed matter 30 shown in FIG. 7, although the display body 10 is affixed on the base material 31, the display body 10 can be supported on a base material by another method. For example, when paper is used as the base material, the display body 10 may be rolled into the paper and the paper may be opened at a position corresponding to the display body 10. Alternatively, when a light-transmitting material is used as the base material, the display body 10 may be embedded therein, or the display body 10 may be fixed to the back surface of the base material, that is, the surface opposite to the display surface. .

  Moreover, the labeled article may not be a printed material. That is, the display body 10 may be supported on an article that does not include a printed layer. For example, the display body 10 may be supported by a luxury product such as a work of art.

  The display body 10 may be used for purposes other than forgery prevention. For example, the display body 10 can be used as a toy, a learning material, or a decoration.

  Examples of the present invention will be described below.

<Example 1>
In Example 1, the display body 10 shown in FIGS. 1 and 2 was manufactured by the following method.
First, an ultraviolet curable resin was applied on a polyethylene terephthalate film (hereinafter referred to as PET film) having a thickness of 25 μm.
Next, the ultraviolet curable resin was cured by irradiating ultraviolet rays from the PET film side while pressing the original plate having a plurality of convex portions on the plate surface against the previous coating film.
Thereafter, the original plate was removed to obtain a light transmission layer 11 having a plurality of concave structures. Here, the depth of the recess was 400 nm, and the distance between the centers of the recesses was 300 nm.
Next, the reflective layer 13 was formed by depositing aluminum (refractive index: 1.48) on the main surface of the light transmission layer 11 on the concave structure side by vacuum vapor deposition.
Further, zinc sulfide (refractive index: 2.37) was deposited on the reflective layer 13 side by a vacuum vapor deposition method to form the refractive layer 14.
Here, the refractive index difference between the reflective layer 13 and the refractive layer 14 was 0.89.

  When the display body 10 thus obtained was observed from the normal direction, the concavo-convex structure region 12a appeared black. Further, when the display body 10 was tilted and observed, the uneven structure region 12a appeared to be colored.

Next, for this display 10, the reflectance in the direction perpendicular to the display surface was measured using the SCI method of JIS Z 8722-condition c, and the brightness L * was calculated.
As a result, the lightness L * was 41.

Further, the display body 10 was irradiated with white light at an incident angle of 40 degrees, and the diffraction efficiency at this time was measured.
As a result, the first-order diffraction efficiency for light having a wavelength of 540 nm was 12.9% at the maximum.

<Example 2>
As shown in FIG. 6, the adhesive layer 21 (polyester urethane, refractive index about 1.5) was formed in the refractive layer 14 side of the display body 10 obtained in Example 1, and the adhesive label 20 was obtained.
The lightness L * of the pressure-sensitive adhesive label 20 thus obtained was measured by the same method as in Example 1. As a result, L * was 42.
Moreover, when the first-order diffraction efficiency regarding the light of 540 nm of the display body 10 was measured by the same method as in the example, the diffraction efficiency was 12.1% at the maximum.

<Comparative Example 1>
A display body was formed in the same manner as in Example 1 except that the refractive layer 14 was not formed.
Here, in Comparative Example 1, no refractive layer was provided, but since the refractive index of the air layer on the back surface of the reflective layer was 1, the refractive index difference between the reflective layer and the air layer was 0.48. .
When the lightness L * of this display was measured in the same manner as in Example 1, L * was 41, which was not different from Example 1.
However, when the first-order diffraction efficiency of the display body with respect to 540 nm light was measured in the same manner as in the example, the diffraction efficiency was 12.4% at the maximum, which was 0.5% lower than in Example 1. .

  That is, it can be seen that the diffraction efficiency becomes higher when the difference in refractive index between the reflective layer and the refractive layer is 0.5 or more (Example 1 and Comparative Example 1).

<Comparative example 2>
An adhesive layer (acrylic adhesive (acrylic resin), refractive index of about 1.5) was formed on the reflective layer side of the display body obtained in Comparative Example 1 to obtain an adhesive label.
Here, although the refractive layer is not provided in the comparative example 2, since the refractive index of the adhesive layer on the back surface of the reflective layer is 1.5, the refractive index difference between the reflective layer and the adhesive layer is 0.02. there were.
When the lightness L * of this pressure-sensitive adhesive label was measured by the same method as in the example, the lightness L * was 43, which was slightly higher than in the example.
Further, when the first-order diffraction efficiency of the display body with respect to light of 540 nm was measured by the same method as in the example, the diffraction efficiency was 11.6% at maximum, which was 0.5% lower than that in Example 2. Compared with Example 1, there was a drop of just over 1%.

  That is, when the difference in refractive index between the reflective layer and the refractive layer is less than 0.2, the brightness of L * increases and the diffraction efficiency decreases (Examples 1 and 2, Comparative Examples 1 and 2). .

In the display body of the present invention, both the brightness of black when observed from a direction perpendicular to the display surface and the coloring (diffraction efficiency) when observed from an oblique direction can be highlighted.

The top view which shows schematically the display body which concerns on 1 aspect of this invention. Sectional drawing along the II-II line of the display body shown in FIG. The perspective view which expands and shows an example of the structure employable for the uneven | corrugated structure area | region of the display body shown in FIG.1 and FIG.2. The perspective view which expands and shows the other example of the structure which can be employ | adopted as the uneven | corrugated structure area | region of the optical element shown in FIG.1 and FIG.2. The figure which shows a mode that an uneven | corrugated structure area | region emits diffracted light roughly. Sectional drawing which shows schematically the adhesive label which concerns on 1 aspect of this invention. The top view which shows an example of a labeled article schematically.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Display body, 11 ... Light transmission layer, 12a ... Uneven structure area, 12b ... Non uneven structure area, 13 ... Reflective layer, 14 ... Refraction layer, 20 ... Adhesive label, 21 ... Adhesive layer, 30 ... Printed matter, 31 ... Base material, 32 ... IC chip, 40 ... printing layer, RP ... concave or convex, L1 ... illumination light, L2 ... regular reflection light or 0th order diffracted light, L3 ... first order diffracted light, N ... normal line

Claims (6)

One main surface includes a concavo-convex structure region in which a plurality of concave portions or convex portions are arranged one-dimensionally or two-dimensionally and a distance between centers of the plurality of concave portions or convex portions is in a range of 200 nm to 500 nm. A light transmissive layer;
A reflective layer supported on the one main surface and covering at least a part of the concavo-convex structure region;
A refractive layer that is supported so as to cover the reflective layer on the one main surface and has a refractive index of 0.2 or more from the refractive index of the reflective layer;
A display body comprising:   The display body according to claim 1, wherein a difference in refractive index between the reflective layer and the refractive layer is 0.5 or more.   The display body according to claim 1, wherein the refractive layer is made of a metal compound, and the refractive index of the metal compound is 0.5 or more higher than the refractive index of the reflective layer. A plurality of the uneven structure regions,
The shape, depth or height, center-to-center distance, and arrangement pattern of the plurality of recesses or projections in at least one of the uneven structure regions are different from those in other uneven structure regions. The display body according to any one of the above.   An adhesive label comprising the display body according to claim 1 and an adhesive layer provided on the display body.   A labeled article comprising the display body according to any one of claims 1 to 4 and an article that supports the display body.

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