JP2013193268A - Display body and labeled article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display body demonstrating a higher forgery prevention effect and a characteristic visual effect.SOLUTION: A display body is a multilayer structure comprising a relief structure forming layer 10, a light reflection layer 30, and a light-transmitting resin layer 40 are laminated. The relief structure forming layer 10 is formed by orderly arrangement or non-orderly arrangement of a plurality of projecting parts or recessed parts each of which is composed of a first surface 21 which is flat and smooth, and nearly in parallel with a display surface of the display body and a second surface 22 nearly in parallel with the first surface 21, and composes a first relief structure forming area 11 where difference in height between the first surface 21 and the second surface 22 composing the projecting parts or recessed parts is nearly constant. The light reflection layer 30 is a thin film layer formed by following a plurality of the projecting parts or recessed parts of the relief structure forming layer 10. The light-transmitting resin layer 40 composes a first resin area 41 and a second resin area 42 composed of transparent or translucent light-transmitting resin with refractive indexes different from each other with respect to visible light. A multicolor structural coloring effect is achieved by the display body.

Description

  The present invention relates to a display technology that exhibits an anti-counterfeit effect, and particularly relates to a display body and an article with a label.

  Generally, securities such as gift certificates and checks, cards such as credit cards, cash cards and ID cards, and certificates such as passports and licenses must be printed with ordinary printed materials to prevent counterfeiting. The display body which has a different visual effect is affixed. In recent years, the distribution of counterfeit goods has become a social problem for articles other than these. Therefore, the opportunity to apply the same forgery prevention technology to such articles is increasing.

  As a display body having a visual effect different from that of a normal printed material, a display body including a diffraction grating in which a plurality of grooves are arranged is known. For example, the display body can display an image that changes according to the observation condition, or can display a stereoscopic image. Further, the spectral color shining in rainbow colors expressed by the diffraction grating cannot be expressed by a normal printing technique. Therefore, a display body including a diffraction grating is widely used for articles that require anti-counterfeiting measures.

  For example, Patent Document 1 describes that a pattern is displayed by arranging a plurality of diffraction gratings having different groove length directions or lattice constants (that is, groove pitches). When the relative position of the observer or the light source with respect to the diffraction grating changes, the wavelength of the diffracted light that reaches the eyes of the observer changes. Therefore, when the above configuration is adopted, an image that changes to a rainbow color can be expressed.

  In a display body using a diffraction grating, a relief type diffraction grating formed with a plurality of grooves is generally used. The relief type diffraction grating is usually obtained by duplicating from an original plate manufactured using photolithography.

  For example, in Patent Document 1, as a method for producing an original plate of a relief type diffraction grating, a flat substrate coated with a photosensitive resist on one main surface is placed on an XY stage, and the stage is controlled under computer control. Describes a method of exposing the photosensitive resist to a pattern by irradiating the photosensitive resist with an electron beam while moving. In addition, the master of the diffraction grating can be formed using two-beam interference.

  In the manufacture of a relief type diffraction grating, usually, an original plate is first formed by such a method, and a metal stamper is prepared therefrom by a method such as electroforming. Next, using this metal stamper as a matrix, a relief type diffraction grating is duplicated. That is, first, for example, a thermoplastic resin or a photocurable resin is applied on a thin transparent substrate in the form of a film or sheet made of polyethylene terephthalate (PET) or polycarbonate (PC). Next, a metal stamper is brought into close contact with the coating film, and heat or light is applied to the resin layer in this state. After the resin is cured, the metal stamper is peeled from the cured resin to obtain a replica of the relief type diffraction grating.

  Generally, this relief type diffraction grating is transparent. Therefore, usually, a light reflection layer is formed on a resin layer provided with a relief structure by depositing a metal such as aluminum or a dielectric such as titanium oxide in a single layer or multiple layers by vapor deposition.

  Then, the display body obtained in this way is affixed on the base material which consists of paper or a plastic film through an adhesive layer or an adhesion layer, for example. As described above, a display body with anti-counterfeit measures is obtained.

  An original plate used for manufacturing a display including a relief type diffraction grating is difficult to manufacture. Further, the transfer of the relief structure from the metal stamper to the resin layer must be performed with high accuracy. That is, high technology is required for manufacturing a display body including a relief type diffraction grating.

  However, as a result of the use of display bodies including relief-type diffraction gratings in many articles that require anti-counterfeiting measures, this technology has become widely recognized, and along with this, the occurrence of counterfeit products tends to increase. is there. For this reason, it has become difficult to achieve a sufficient anti-counterfeit effect using a display body that is characterized only by exhibiting rainbow light by diffracted light.

US Pat. No. 5,058,992

  The objective of this invention is providing the display body which shows the high forgery prevention effect and the characteristic visual effect.

  In order to achieve the above object, a first invention is a display body having a multilayer structure in which at least a relief structure forming layer, a light reflecting layer, and a light transmitting resin layer are laminated, and the relief structure forming layer includes a display A plurality of convex portions or concave portions including a first surface that is substantially parallel and smooth to the display surface of the body and a second surface that is substantially parallel to the first surface are formed in an orderly or non-ordered manner. Forming a first relief structure forming region in which a difference in height between the first surface and the second surface constituting the convex portion or the concave portion is substantially constant, and the light reflecting layer includes the relief structure forming layer and the light transmitting property. It is a thin film layer provided at least in part between the resin layers and formed following the shape of a plurality of convex portions or concave portions of the relief structure forming layer, and the light transmissive resin layer is Transparent or translucent light transmission with different refractive indexes A display body, characterized in that forming the first resin region and the second resin region made of resin.

  According to a second aspect of the present invention, there is provided a second relief in which a height difference between the first surface and the second surface constituting the convex portion or the concave portion is substantially constant, and the height difference is different from the first relief structure forming region. The display body according to claim 1, further comprising a structure forming region.

  According to a third aspect of the present invention, the first resin region and the second resin region, and the first relief structure forming region and the second relief structure forming region are partially overlapped with each other. A display body according to claim 2.

  According to a fourth aspect of the present invention, the light reflecting layer has a single-layer or multi-layer structure of metal or dielectric, and the layer thickness is 30 nm to 70 nm, preferably 50 nm. Or a display body according to item 1.

  Moreover, 5th invention is a display body of any one of Claim 1 thru | or 3 characterized by the refractive index difference of the said 1st resin area | region and 2nd resin area | region being 0.15 or more. .

  According to a sixth aspect of the present invention, the relief structure forming layer is made of a transparent or translucent light transmissive resin having a refractive index different from that of the first resin region and the second resin region. Item 6. The display body according to any one of Items 1 to 5.

  In a seventh aspect of the present invention, the relief structure forming layer further includes a third relief structure forming region including any one of a diffraction grating, an antireflection structure, a light scattering structure, and a flat surface. It is a display body of any one of Claims 1 thru | or 6.

  According to an eighth aspect of the present invention, there is provided a labeled article comprising the display according to any one of claims 1 to 7 and an article supporting the display.

  According to the first aspect of the present invention, the display body includes a relief structure forming layer having a plurality of convex portions or concave portions. The plurality of convex portions or concave portions has a substantially rectangular cross-sectional structure composed of a first surface that is substantially parallel and smooth to the display surface of the display body, and a second surface that is substantially parallel to the first surface. It is. When white illumination light is incident on such a structure, the optical path length between the light reflected by the first surface and the light reflected by the second surface (the geometric distance multiplied by the refractive index). A difference occurs in the light, and light of a specific wavelength is weakened by light interference corresponding to the optical path length. Therefore, the emitted light is not white, but can be displayed as an arbitrary color tone with a specific wavelength determined by the difference in height between the first surface and the second surface. The light having a plurality of wavelengths that has not been attenuated by the interference emitted from the relief structure forming layer varies in its emission angle depending on whether the plurality of protrusions or recesses are arranged in an orderly or non-ordered manner. . As a result, the light of each wavelength is mixed and a so-called pastel display color can be displayed by mixing the light of a plurality of wavelengths. Since these lights are mixed, it is difficult to exhibit an iridescent color change accompanying a change in observation angle different from the diffracted light by the conventional diffraction grating pattern. However, the light emitted by the interference can be observed only in directions determined by factors such as the size, arrangement interval, density, etc. of the plurality of convex portions or concave portions, and the emitted light cannot reach other directions. No display color is observed. Therefore, a visible or invisible change in display color according to the viewing angle is obtained, and a visual effect different from that of a normal printed material is realized.

  The light reflecting layer formed following the shape of the convex or concave portions of the relief structure forming layer contributes to more strongly reflecting incident light, and can display any color tone with the specific wavelength more clearly To.

  The light-transmitting resin layer has a first resin region and a second resin region made of a transparent or translucent light-transmitting resin having different refractive indexes with respect to visible light. Since the light incident on the first resin region and the second resin region having different refractive indexes has different optical path lengths, when the height difference of the convex portion or the concave portion is the same, the emitted light has different wavelengths. It becomes. Accordingly, the first resin region and the second resin region can display different colors.

  The display color exhibited by this optical action is unlikely to cause a rainbow color change due to a change in the position of the illumination or the observer as in the conventional diffraction grating pattern. Can achieve different visual effects. As a result, a display body that exhibits a characteristic visual effect and a high anti-counterfeiting effect can be obtained.

  According to the second invention, the display body is composed of a convex portion or a concave portion having a height difference different from a height difference between the first surface and the second surface constituting the convex portion or the concave portion of the first relief structure forming region. A second relief region is further provided. Since the height difference of the concavo-convex structure in the first relief structure forming region and the height difference of the concavo-convex structure in the second relief structure forming region are different from each other, the optical path length is changed by changing the geometric distance when the incident light is reflected. Differently, light of different wavelengths interferes and light of different wavelengths is emitted. By having a first relief structure formation region and a second relief structure formation region, and further including a first resin region and a second resin region having different refractive indexes, multicolor display is possible.

  According to the third invention, the first resin region and the second resin region and the first relief structure forming region and the second relief structure forming region are spatially partially separated from each other when the display body is observed. Are arranged and configured in an overlapping relationship. Accordingly, the optical path length varies depending on the height difference of the structure and the refractive index difference according to the overlapping combination, and different colors can be displayed.

  According to a fourth aspect of the present invention, the light reflecting layer has a structure in which a metal such as aluminum, gold or silver, or a dielectric such as zinc sulfide or titanium oxide is provided in a single layer or a multilayer structure. The thickness of the light reflecting layer is 30 nm or more and 70 nm or less, and preferably 50 nm. By providing the light reflecting layer having such a structure so as to follow the shape of the plurality of convex portions or concave portions of the relief structure forming layer, a sufficient amount of reflected light can be obtained without dulling the rectangular shape of the convex portions or concave portions as much as possible. Can be obtained.

  Moreover, according to 5th invention, the refractive index difference of the said 1st resin area | region and 2nd resin area | region is 0.15 or more. When the difference in refractive index is 0.15 or more, the difference in the optical path length of light emitted from the relief structure forming layer is increased, and the display colors when the first resin region and the second resin region are observed are clearly defined. Can be different colors.

  According to a sixth aspect of the invention, the relief structure forming layer is made of a transparent or translucent light transmissive resin, and the refractive index thereof is different from that of the first resin region and the second resin region. By adopting such a relief structure forming layer, different display colors can be seen in the first resin region and the second resin region when observed from the light transmissive resin layer side, and the relief structure forming layer side When observed from the above, a display body is obtained in which a display color different from that of the first resin region and the second resin region can be observed.

  According to the seventh invention, the design of the display body is provided by providing the relief structure forming layer with a third relief structure forming region comprising any one of a diffraction grating, an antireflection structure, a light scattering structure, and a flat surface. It is possible to further improve the anti-counterfeiting effect and to realize a higher anti-counterfeit effect.

  Further, according to the eighth invention, it is possible to give a high anti-counterfeiting effect to a conventional article by attaching or combining the display body of the present invention to a printed matter, a card, or another article.

It is the top view which showed roughly the display body which concerns on one Embodiment of this invention. It is an expanded sectional view of the display body which follows the II-II line of FIG. It is the figure which showed roughly a mode that the diffraction grating with a narrow pitch inject | emits + 1st-order diffracted light. It is the figure which showed roughly a mode that the diffraction grating with a wide pitch inject | emits + 1st-order diffracted light. It is a perspective view which shows an example of the structure employable for the 1st relief structure formation area of the display body of this invention. It is a perspective view which shows another example of the structure employable for the 1st relief structure formation area of the display body of this invention. It is the schematic which shows the mode of the diffracted light inject | emitted from a diffraction grating. It is the schematic which shows the mode of the light inject | emitted from the 1st relief structure formation area. It is a top view of the 1st relief structure formation area shown in FIG.5 and FIG.8. It is a perspective view which shows an example of the structure which has the directivity employable for the 1st relief structure formation area of the display body of this invention. It is the schematic which shows the mode of the light inject | emitted from the 1st relief structure formation area shown in FIG. It is a perspective view which shows the structural example of a 1st resin area | region and a 2nd resin area | region. It is a conceptual diagram which shows the propagation speed of the light which injected into the 1st resin area | region and the 2nd resin area | region. It is sectional drawing which shows the structural example of a 1st relief structure formation area and a 2nd relief structure formation area. It is sectional drawing which shows the structural example of a 1st relief structure formation area | region, a 2nd relief structure formation area | region, a 1st resin area | region, and a 2nd resin area | region. It is sectional drawing which shows an example of the structure where the 1st relief structure formation area and the 2nd relief structure formation area overlapped with the 1st resin area and the 2nd resin area partially. It is sectional drawing which shows the example of a preferable light reflection layer. It is sectional drawing which shows the example of the light reflection layer which is not preferable. It is sectional drawing which shows the example of the light reflection layer which is not preferable. It is a perspective view which shows an example of the reflection preventing structure employable as a 3rd relief structure formation area. It is a perspective view which shows an example of the light-scattering structure employable as a 3rd relief structure formation area. It is sectional drawing which shows the structural example of a 1st relief structure formation area and a 3rd relief structure formation area. It is a top view which shows roughly an example of the labeled article formed by making an anti-counterfeit label supported on the article. It is sectional drawing along the XXIIII-XXIIII line of the labeled article shown in FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that, throughout all the drawings, the same reference numerals are given to components that exhibit the same or similar functions, and redundant descriptions are omitted.

(About the structure of the display)
FIG. 1 is a plan view schematically showing a display body according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II of the display shown in FIG. 1 and 2, the x direction and the y direction are parallel to the display surface of the display body and are perpendicular to each other. The z direction is a direction perpendicular to the x direction and the y direction.

  As shown in FIG. 1, the display body 1 displays the characters “TP” due to the difference in display color between the first resin region 41 and the second resin region 42 arranged on the upper surface side when viewed from the observer. ing. On the back side of the first resin region 41 and the second resin region 42, the first relief structure forming region 11 is formed over the entire display body 1. As shown in FIG. 2, the relief structure forming layer 10 is arranged on the opposite side (back side) from the direction in which the observer observes the display body 1, and one surface of the relief structure forming layer 10 is on the surface of the display body 1. A plurality of convex portions 20 each including a first surface 21 that is substantially parallel and smooth to the display surface and a second surface 22 that is substantially parallel to the first surface 21 are formed. The first relief structure forming region 11 is a region where a plurality of convex portions 20 of the relief structure forming layer 10 are formed. Further, the light reflecting layer 30 is formed so as to follow the shape of the concavo-convex structure of the relief structure forming layer 10. Further, a light transmissive resin layer 40 is further formed on the upper surface (observer side) of the light reflecting layer 30. The light transmissive resin layer 40 includes a first resin region 41 and a second resin region 42 made of transparent or translucent light transmissive resins having different refractive indexes.

  As a material of the relief structure forming layer 10, for example, an ionizing radiation curable resin, a thermoplastic resin, or a synthetic resin such as a thermosetting resin can be used.

As the light reflection layer 30, for example, a metal layer made of a metal material such as aluminum, silver, gold, and alloys thereof can be used. Alternatively, a dielectric layer made of zinc sulfide ZnS or titanium oxide TiO ₂ having a refractive index different from that of the light transmissive resin layer 40 may be used. Alternatively, as the light reflecting layer 30, a laminate of dielectric layers having different refractive indexes between adjacent ones, that is, a dielectric multilayer film may be used. The light reflecting layer 30 can be formed by, for example, a vapor deposition method such as a vacuum evaporation method or a sputtering method.

  The light reflecting layer 30 contributes to an increase in the amount of reflected light by efficiently reflecting and emitting the light incident on the display body 1. The light reflecting layer 30 may be formed so as to cover the entire surface of the relief structure forming layer 10 or only a part thereof. The light reflecting layer 30 covering only a part of the relief structure forming layer 10, that is, the light reflecting layer 30 patterned with a pattern, characters, symbols, etc. is formed by, for example, forming a light reflecting layer as a continuous film by vapor deposition. It is obtained by forming and then dissolving a part thereof with chemicals or the like. Alternatively, the patterned light reflection layer 30 is formed as a continuous film, and thereafter, an adhesive material having a higher adhesion force to the light reflection layer 30 than the adhesion force of the light reflection layer 30 to the relief structure forming layer 10 is used. Further, it can be obtained by peeling a part of the light reflecting layer 30 from the relief structure forming layer 10. Alternatively, the patterned light reflecting layer 30 can be obtained by a method of performing vapor deposition using a mask or a method of using a lift-off process.

  The light transmissive resin layer 40 is a transparent or translucent, particularly colorless and transparent layer having light transparency. As a material of the light transmissive resin layer 40, for example, a synthetic resin such as an ionizing radiation curable resin, a thermoplastic resin, or a thermosetting resin can be used.

  The display body 1 can further include layers that realize other functions such as an adhesive layer, a coat layer, and a print layer.

  For example, the adhesive layer is provided in close contact with the relief structure forming layer 10. The adhesive layer is used to attach the display body 1 to a printed material or other articles. When a synthetic resin material capable of forming a concavo-convex structure is used as the adhesive layer, it is also possible to serve as the adhesive layer and the relief structure forming layer. When the display body 1 is attached to a transparent printed matter (such as a plastic card-like article) having a light transmission property or a transparent article, the display body 1 can be observed from the back side through the transparent printed matter or article. is there. In that case, a transparent, translucent, especially colorless and transparent material is used for the adhesive layer.

  The coat layer is, for example, a hard coat layer intended to prevent the surface of the display body from being scratched during use, an antifouling layer or an antistatic layer that suppresses adhesion of dirt. The coat layer is provided on the front side (observer side) of the laminate of the display body 1. Also for the coat layer, it is preferable to use a transparent, translucent, and particularly colorless and transparent material so as not to impair the visibility of the display 1.

  The print layer is provided, for example, on the viewer side of the laminate of the display body or between the relief structure forming layer and the adhesive layer. By providing the printing layer, the design of the display body can be improved, and information to be displayed on the display body can be easily added. The print layer is preferably provided partially so as not to cover the entire display of the display body, or ink, pigment, or dye showing transparency to visible light is used. Moreover, you may use functional inks, such as ink in which concealment information is displayed by light emission of an ultraviolet-ray or infrared rays, and phosphorescent ink.

(About optical properties of diffraction gratings)
In describing the visual effect realized by the concavo-convex structure including a plurality of convex portions or concave portions formed in the relief structure forming layer of the display body 1, first, the grating constant (groove pitch) of the diffraction grating, and the illumination light The relationship among the wavelength of the light, the incident angle of the illumination light, and the exit angle of the diffracted light will be described.

  When illumination light is irradiated onto the diffraction grating using the illumination light source, the diffraction grating emits strong diffracted light in a specific direction according to the traveling direction and wavelength of the illumination light that is incident light.

  The exit angle β of the m-th order diffracted light (m = 0, ± 1, ± 2,...) is expressed by the following formula (when the light travels in a plane perpendicular to the groove length direction of the diffraction grating: It can be calculated from 1).

式（１）において、ｄは回折格子の格子定数を表し、ｍは回折次数を表し、λは入射光及び回折光の波長を表している。また、αは、０次回折光、即ち、正反射光ＲＬの射出角を表している。換言すれば、αの絶対値は照明光の入射角と等しく、反射型回折格子の場合には、照明光の入射方向と正反射光の射出方向とは、回折格子が設けられた界面の法線ＮＬに関して対称である。

In Expression (1), d represents the grating constant of the diffraction grating, m represents the diffraction order, and λ represents the wavelengths of incident light and diffracted light. Α represents the exit angle of the 0th-order diffracted light, that is, the regular reflection light RL. In other words, the absolute value of α is equal to the incident angle of the illumination light, and in the case of a reflective diffraction grating, the incident direction of the illumination light and the emission direction of the specularly reflected light are the method of the interface where the diffraction grating is provided. Symmetric with respect to line NL.

  When the diffraction grating is a reflection type, the angle α is 0 ° or more and less than 90 °. In addition, when illumination light is irradiated to the interface provided with the diffraction grating from an oblique direction, and the angle in the normal direction, that is, two angle ranges having a boundary value of 0 °, the angle β is determined as follows. A positive value is obtained when the exit direction and the exit direction of the specularly reflected light are within the same angular range, and a negative value when the exit direction of the diffracted light and the incident direction of the illumination light are within the same angular range.

  FIG. 3 is a diagram schematically showing a state in which a diffraction grating having a small grating constant emits first-order diffracted light. FIG. 4 is a diagram schematically showing how a diffraction grating having a large grating constant emits first-order diffracted light.

  The point light source LS emits white light including a light component R having a wavelength in the red region, a light component G having a wavelength in the green region, and a light component B having a wavelength in the blue region. The light components G, B, and R emitted from the point light source LS are incident on the diffraction grating GR at an incident angle α. The diffraction grating GR emits the diffracted light DL_g as a part of the light component G at an exit angle β_g, emits the diffracted light DL_b as a part of the light component B at an exit angle β_b, and diffracted light as a part of the light component R. DL_r is emitted at an emission angle β_r. Although not shown, the diffraction grating GR also emits diffracted light of other orders at an angle derived from Equation (1).

  Thus, under certain illumination conditions, the diffraction grating emits diffracted light at different exit angles depending on its wavelength. Therefore, under white light sources such as the sun and fluorescent lamps, the diffraction grating emits light having different wavelengths at different angles. Therefore, under such illumination conditions, the display color of the diffraction grating changes to iridescent as the observation angle changes. Further, as the lattice constant increases, the diffracted light is emitted in a direction closer to the regular reflection light RL, and the difference between the emission angles β_g, β_b, and β_r becomes smaller.

  Next, the relationship between the grating constant of the diffraction grating, the wavelength of the illumination light, and the intensity (diffraction efficiency) of the diffracted light in the direction of the emission angle of the diffracted light will be described.

  According to Expression (1), when illumination light is incident on the diffraction grating having the grating constant d at an incident angle α, the diffraction grating emits diffracted light at an emission angle β. At this time, the diffraction efficiency for light of wavelength λ varies depending on the grating constant of the diffraction grating, the depth of the groove, and the like, and can be calculated from the following equation (2).

ここで、ηは回折効率（０乃至１の値）を表し、ｒは回折格子の溝の深さを表し、Ｌは回折格子の溝の幅を表し、ｄは格子定数を表し、θは照明光の入射角を表し、λは照明光及び回折光の波長を表している。なお、この式（２）は、溝の長さ方向に垂直な断面が矩形波状であり、溝が比較的浅い回折格子について成り立つものである。

Here, η represents the diffraction efficiency (value between 0 and 1), r represents the groove depth of the diffraction grating, L represents the groove width of the diffraction grating, d represents the grating constant, and θ represents illumination. It represents the incident angle of light, and λ represents the wavelengths of illumination light and diffracted light. This equation (2) holds true for a diffraction grating in which the cross section perpendicular to the length direction of the groove is a rectangular wave and the groove is relatively shallow.

  As is apparent from the equation (2), the diffraction efficiency η varies depending on the groove depth r, the lattice constant d, the incident angle θ, and the wavelength λ. In addition, the diffraction efficiency η tends to gradually decrease as the diffraction order m becomes higher.

(Optical properties realized by the relief structure forming layer)
Next, optical properties realized by the first relief structure forming region will be described.

  FIG. 5 is a perspective view schematically showing an example of a structure that can be employed in the first relief structure forming region 11. The first relief structure forming region 11 includes a smooth first surface 21 and a plurality of convex portions 20 each having an upper surface and a side surface (or a plurality of concave portions each having a bottom surface and a side wall). Contains. The top surface of the convex portion 20 (or the bottom surface of the concave portion) is a second surface 22 that is parallel to the first surface 21 and smooth. FIG. 5 shows an example in which the first relief structure forming region 11 includes a plurality of protrusions 20 and the second surface 22 forms the upper surface of the protrusions 20. Even in the case where a plurality of recesses are formed in the region 11 and the second surface is constituted by the bottom surfaces of the plurality of recesses, the following optical properties are similarly exhibited. Hereinafter, a plurality of convex portions will be illustrated and optical description will be described, and illustration and description of the plurality of concave portions will be omitted.

  In FIG. 5, the circular protrusions 20 are regularly arranged in a predetermined direction on one surface of the first relief structure forming region 11. The orderly arrangement indicates that the protrusions 20 are arranged at equal intervals or regularity, for example, a square lattice, a rectangular lattice, or a triangular lattice.

  FIG. 6 is a perspective view showing an example of another structure that can be employed in the first relief structure forming region 11. The circular protrusions 20 are formed in an unordered arrangement (random arrangement) in the first relief structure forming region 11. When the convex parts 20 are arranged non-orderly, the convex parts 20 may be formed so as to overlap each other.

  As another example of the shape of the convex portion, an elliptical shape, an octagonal shape, a star shape, or a polygonal shape such as a cross can be arbitrarily employed. Moreover, the convex part from which a shape differs may be mixed in the 1st relief structure formation area.

  FIG. 7 is a schematic view showing a state of diffracted light emitted when white illumination light is irradiated on a normal diffraction grating. In the diffraction grating GR composed of a plurality of grating lines regularly formed in the direction parallel to the y-axis as shown in FIG. 7, when the illumination light IL is incident, the y-axis (longitudinal direction of the grating lines) Diffracted beams DL_r, DL_g, and DL_b are emitted in the orthogonal direction (x-axis direction).

  On the other hand, FIG. 8 is a schematic view showing a state of diffracted light emitted from the first relief structure forming region 11. FIG. 9 is a plan view of the first relief structure forming region 11 shown in FIGS. 5 and 8.

  When white illumination light is incident on the structure as shown in FIG. 8, the unevenness formed by the second surface 22 by the plurality of convex portions 20 formed in the first relief structure forming region 11 and the first surface 21 around the second surface 22. Diffracted light is emitted depending on the structure. In the structure in which the protrusions 20 are arranged orderly apart from each other as shown in FIG. 8, diffracted light is emitted not only in the x-axis direction but also in many azimuth directions on the xy plane. Here, even in a configuration in which a plurality of convex portions 20 are arranged in an orderly manner as indicated by alternate long and short dash lines A, B, and C shown in FIG. 9, the apparent arrangement interval differs depending on the direction. Therefore, it can be said that the first relief structure forming region 11 shown in FIGS. 8 and 9 is a concavo-convex structure having various arrangement intervals (that is, lattice constant d). When light is incident on such a structure, a large number of concavo-convex structures with different lattice constants d are superimposed, and the emitted diffracted light is not emitted for different emission angles for each wavelength, Light of each wavelength is emitted while being superimposed at various angles.

  Further, FIG. 8 shows a state in which light is incident on one point of the first relief structure forming region 11, but actually, the illumination light source has a certain area, and the light is not incident on one point. , Incident in a plane. Therefore, the light observed by the observer at a fixed point is a combination of light having a certain range of wavelengths, and as a result, colors of light having a plurality of wavelengths are observed.

  Here, as shown in Expression (2), the amount of light of the diffracted light emitted from the diffractive structure, that is, the diffraction efficiency changes according to the wavelength. In particular, assuming that the grating line width L of the diffraction grating and the pitch d of the grating lines are constant, the diffraction efficiency η is the height r of the diffraction grating (corresponding to the height difference between the first surface 21 and the second surface 22). It is uniquely determined by the wavelength λ of the illumination light.

  Therefore, when the first relief structure forming region 11 is observed from a fixed point, the wavelength component of visible light does not reach the eyes evenly, and the height of the convex portion 20 provided in the first relief structure forming region (first The diffraction efficiency of light of a specific wavelength is lowered due to light interference according to the height difference between the surface 21 and the second surface 22, and as a result, the light reaching the observer is a specific part of the incident white illumination light. The light has a weak wavelength component. Therefore, when an observer observes the 1st relief structure formation area 11 under a white illumination light source, he will perceive the light which produced the difference in the light quantity for every wavelength.

  For example, when observing a first relief structure forming region provided with a convex portion of a certain height, the diffraction efficiency of blue (wavelength 460 nm) light becomes weak, and the wavelength component of diffracted light that reaches the eyes of the observer Is red (wavelength 630 nm) and green (wavelength 540 nm), the observed color is yellow, and when observing another first relief structure forming region provided with a convex portion of another height If the diffraction efficiency of light of the red wavelength component is weak and the wavelength components of the diffracted light reaching the eyes of the observer are green and blue, the observed color is cyan (light blue).

  FIG. 8 shows, as an example, a state in which the light IL from the white illumination light source enters the first relief structure forming region 11, the red diffracted light DL_r is weakened, and the green diffracted light DL_g and the blue diffracted light DL_b are emitted. Is shown.

  The display color displayed by such a principle is not observed when the observer is at a position where the diffracted light does not reach. Thereby, unlike a normal printed matter, two states can be realized: a state where the display color can be recognized and a state where the display color cannot be recognized depending on the position of the illumination light source or the observer. This is different from ordinary printed matter in which almost the same color can be perceived in many ranges.

  Even in a structure in which a plurality of convex portions 20 are arranged in an unordered manner as shown in FIG. 6, diffracted light is emitted. Also in the case as shown in FIG. 6, since the value of the lattice constant d shown in the equation (1) varies, the emission angle of the diffracted light varies depending on the location. Therefore, similarly to the structure shown in FIG. 5, the diffracted light reaching the fixed point is light of many wavelengths excluding light of a specific wavelength, and color mixture of these lights is observed. By forming a plurality of irregularly arranged convex portions 20 in the first relief structure forming region 11, light of each wavelength is emitted at various angles as compared with the regularly arranged structure as shown in FIG. Therefore, a display in which the change in rainbow color due to diffraction is further suppressed is possible.

  In this way, the light from the illumination light source is incident on the surface of the display body, the incident light is reflected and emitted by the relief structure of the display body, and the conditions under which the observer can perceive the light visually are defined as `` normal illumination conditions Is defined. For example, in a general room, the light from the illumination light is incident on the surface of the display body substantially perpendicularly to the display body under illumination light such as a fluorescent lamp, and the condition for the observer to observe the display body visually, “Normal lighting conditions” are conditions in which light from the illumination light is incident on the surface of the display body approximately perpendicularly to the display body under sunlight or other illumination light, and the observer observes the display body. It corresponds to. Here, “normal illumination light” refers to white illumination light such as an indoor fluorescent lamp or outdoor sunlight.

  Further, “conditions other than normal illumination conditions” indicate conditions under which the observer cannot perceive light emitted from the display body. For example, the light from the illumination light is incident on the surface of the display body substantially horizontally, that is, at a steep angle, and light is not emitted from the relief structure of the display body, or the light is emitted by diffraction from the relief structure of the display body. Even so, a condition in which the observer views the display body from an angle at which the diffracted light does not reach corresponds to a “condition other than normal illumination conditions”.

  In order to have a structure in which colors composed of light of a plurality of wavelengths can be observed under normal illumination conditions, it is better to have a slightly larger structure of about 5 μm to 10 μm in the case of regularly arranged convex parts, and adjacent convex parts The arrangement interval between the parts is, for example, in the range of 5 μm to 10 μm. In the case of a large structure, since the difference in the exit angle of the diffracted light with respect to each wavelength is small as is clear from the equation (1), the display color changes to a so-called rainbow color even if the position of the illumination light source or the observer changes. Without this, colors with multiple wavelengths can be observed stably.

  On the other hand, in the case of non-ordered arrangement, it is preferable that the convex portions have a slightly smaller structure of about 0.3 μm to 5 μm. In this case, the arrangement interval between adjacent convex portions is within a range of, for example, 0.3 μm to 5 μm. It is in. When a small structure is formed with a small arrangement interval, the emission angle of the diffracted light becomes large as is apparent from Equation (1). For this reason, in the structure arranged in an orderly manner, it is easy to change the color to iridescent, but by arranging it in an unordered manner, light of a plurality of wavelengths can easily reach a fixed point where the observer is present. In addition, when the small structures are arranged in an unordered manner, the emission angle of the diffracted light becomes large, so that there is an advantage that display colors by a plurality of lights can be observed in a wide range.

  In the structure adopted in the first relief structure forming region, the height difference between the first surface and the second surface forming the concavo-convex structure is substantially the same, so that the diffraction efficiency of light of a specific wavelength is lowered by light interference. In addition, since there is an effect of suppressing a decrease in the diffraction efficiency of light of other wavelengths, it is possible to display a specific color with light of a plurality of wavelengths that does not decrease the diffraction efficiency. If the height difference between the first surface and the second surface forming the concavo-convex structure is not substantially the same, the wavelength range of the light where the diffraction efficiency is reduced is widened, resulting in a decrease in the saturation of the displayed color and the incidence. Display color close to white, which is not much different from the wavelength distribution of the light. In general light scattering structures, fine structures are randomly arranged, but since the depth of the structure is also random, it does not have the effect of reducing the diffraction efficiency of light of a specific wavelength. Since the incident white light is scattered and emitted as it is, a white display color is obtained. Therefore, in order to be able to display a specific unique color, it is desirable that the height difference between the first surface and the second surface is the same.

  The height difference between the first surface and the second surface for exhibiting such an optical effect is, for example, in the range of 0.1 μm to 0.5 μm, and typically in the range of 0.15 μm to 0.4 μm. Is in.

  When the height difference between the first surface and the second surface is reduced, the color of the colored light emitted from the first relief structure forming region becomes light. Also, if this height difference is reduced, external factors during manufacturing, for example, changes in the state and environment of the manufacturing apparatus and slight changes in the material composition will greatly affect the optical properties of the first relief structure forming region. Become. On the other hand, when this height difference is large, it becomes difficult to form the first relief structure forming region with high shape accuracy and dimensional accuracy.

  The side surface of each convex portion is typically substantially perpendicular to the first surface and the second surface. This side surface may be inclined with respect to the first surface and the second surface. Again, it is desirable that the side surface of each convex portion be more vertical, and the saturation of the display color decreases as the side surface becomes inclined.

  Further, the structure employed in the first relief structure forming region emits diffracted light in many azimuth directions on the xy plane as shown in FIGS. Even if the direction changes slightly, it is possible to observe a color composed of a plurality of wavelengths. For this reason, it is possible to avoid or reduce the phenomenon that the display color changes to a rainbow color under normal illumination conditions as in the conventional diffraction grating.

  Still another structure that can be employed in the first relief structure forming region is a structure having directivity. FIG. 10 is a perspective view showing an example of the first relief structure forming region 11 composed of a plurality of linear structure protrusions 20 having a shape extending in the y-axis extending direction. The width of the convex portion 20 is, for example, in the range of 0.2 μm to 10 μm, and typically in the range of 0.3 μm to 5 μm. The ratio of the dimension in the length direction to the dimension in the width direction of the protrusion 20 is, for example, 2 or more, and typically 10 or more. If this ratio is reduced, it becomes difficult for the observer to perceive optical anisotropy described later.

  The arrangement of the convex portions is determined so as not to constitute a diffraction grating or a hologram that emits diffracted light that can be perceived by the naked eye. Here, the distance between the center lines of the convex portions 20 adjacent in the width direction is irregular. Either the distance between the centers of the protrusions or the width of the protrusions may be equal.

  The arrangement interval between the protrusions adjacent in the width direction is, for example, in the range of 0.2 μm to 10 μm, and typically in the range of 0.3 μm to 5 μm. The convex part has various lengths. Moreover, those positions with respect to the length direction of the convex portions are irregular. The convex portions may have equal lengths, and may be regularly arranged in the length direction.

  With respect to such a structure, when white illumination light is incident from vertically above the display body as shown in FIG. 11, the incident light IL is perpendicular to the length direction of the convex portion 20 (x-axis extending direction). The diffracted lights DL_g and DL_b are emitted along the line No., and the diffracted lights are not emitted in the length direction of the convex portion 20 (the extending direction of the y-axis). Here, the height of the projection 20, that is, the height difference between the first surface 21 and the second surface 22 is the same as the structure shown in FIG. 8, and the red diffracted light DL_r is weakened to obtain a cyan display color. It is done.

  Thus, by providing a structure having directivity (directivity), it is possible to control the azimuth angle direction in which the diffracted light is emitted. Even in this case, since the height difference between the first surface 21 and the second surface 22 is the same, the light of a specific wavelength is weakened according to the height difference. The diffracted light observed in the orthogonal direction displays a unique color, and since the plurality of convex portions are randomly arranged, it does not change to iridescent, and in the direction orthogonal to the length direction of the convex portions. Displays the same unique color over a wide range.

  When the area of the orthogonal projection of the first relief structure forming region 11 to a plane parallel to the first surface 21 and the second surface 22 is S, the ratio S1 / S of the area S1 of the first surface 21 to the area S is: For example, it is in the range of 20% to 80%, and typically in the range of 40% to 60%. Further, the ratio S2 / S of the area S2 of the second surface 22 to the area S is, for example, in the range of 80% to 20%, and typically in the range of 60% to 40%. The ratio (S1 + S2) / S of the sum S1 + S2 of the area S1 and the area S2 to the area S is, for example, 10% to 100%, and typically 50% to 100%. When each of the ratios S1 / S and S2 / S is 50%, the brightest display is possible. According to an example, when one of the ratios S1 / S and S2 / S is 20% and the other is 80%, the achievable brightness is 50% for each of the ratios S1 / S and S2 / S. It is about 30% of the achievable brightness.

  FIG. 12 is applicable to this patent in which the light reflecting layer 30 and the light transmissive resin layer 40 are sequentially laminated on the surface of the relief structure forming layer 10 where the uneven structure of the first relief structure forming region 11 is formed. 2 is a perspective view schematically showing a configuration example of a display body 1. FIG. The light transmissive resin layer 40 is divided into a first resin region 41 and a second resin region 42 having different refractive indexes.

  Since the first resin region 41 and the second resin region 42 have different refractive indexes, the optical path length when light incident on each region and reflected and emitted from the uneven structure travels is changed.

  FIG. 13 shows the light that travels through the first resin region 41 and the second resin region 42 when the white illumination light enters the display body 1 shown in FIG. It is sectional drawing which shows the mode of advancing. Here, it is assumed that the refractive index of the first resin region 41 is larger than the refractive index of the second resin region 42. The dots shown in FIG. 13 are plots of the distance of light traveling in a certain time. In FIG. 13, the light incident from the upper left side of the display body 1 propagates in the air at the same speed, but the light traveling in the first resin region 41 and the second resin region 42 depends on the refractive index of the resin material. Propagate at different speeds. Here, since the refractive index of the first resin region 41 is larger than the refractive index of the second resin region 42, the light propagation speed is slower in the first resin region 41, and the dot arrangement interval shown in the figure is It is narrower. As a result, the light that is reflected from the first surface 21 and the second surface 22 of the first resin region 41 and the second resin region 42 and reaches the outside is emitted through different optical path lengths, and thus weakens due to interference. The wavelengths of light are different from each other. For this reason, the displayed color changes depending on the refractive index of the light-transmitting resin layer even in the same uneven structure.

  The optical path length of light propagating through the light transmissive resin layer, reflected by the first and second surfaces of the concavo-convex structure and emitted to the outside is not only the refractive index of the light transmissive resin layer, but also the height of the concavo-convex structure. That is, it can also be controlled by the height difference between the first surface and the second surface. If the height difference between the first surface and the second surface is small, the difference in the optical path length is also small. If the height difference between the first surface and the second surface is large, the difference in the optical path length is also large.

  FIG. 14 is a cross-sectional view showing an example in which the second relief structure forming region 12 is formed adjacent to the first relief structure forming region 11, and the concavo-convex structure formed in the second relief structure forming region 12 is the first The height difference is larger than the uneven structure of the 1 relief structure forming region 11. When white light is incident on the first relief structure forming region 11 and the second relief structure forming region 12, the optical path length of the light changes, so that different unique colors can be observed.

  Here, as shown in FIG. 15, the first resin region 41 is formed on the first relief structure forming region 11 via the light reflecting layer 30, and the second resin is similarly formed on the second relief structure forming region 12. When the region 42 is formed through the light reflecting layer 30, the optical path length of the white light incident on each region is uniquely determined by the refractive index and layer thickness of each region and the height difference of the concavo-convex structure, and each display is different. Color can be obtained. FIG. 15 is a cross-sectional view illustrating a configuration example of the first relief structure forming region 11, the second relief structure forming region 12, the first resin region 41, and the second resin region 42. It is very difficult to accurately imitate both the refractive index and the layer thickness of each resin region, and the height difference of the concavo-convex structure provided in each relief structure forming region, and it is very high by adopting such a configuration. It is possible to realize a display body having an anti-counterfeit effect.

  Further, the first relief structure forming region 11 and the second relief structure forming region 12, and the first resin region 41 and the second resin region 42 may be arranged so as to partially overlap each other. FIG. 16 is a cross-sectional view showing an example in which the first relief structure forming region 11 and the second relief structure forming region 12, and the first resin region 41 and the second resin region 42 are arranged so as to partially overlap each other. . Similarly to the partial area A50 formed by overlapping the first relief structure forming area 11 and the first resin area 41, the partial area B51 (combination of the second relief structure forming area 12 and the first resin area 41), the partial area C52 (combination of the second relief structure forming region 12 and the second resin region 42) and a partial region D53 (combination of the first relief structure forming region 11 and the second resin region 42) are configured, and they are mutually resinous. Since the combination of the refractive index of the region and the height difference of the concavo-convex structure is different, the optical path lengths of the emitted light are different from each other, and different unique colors can be displayed. With the display body having such a configuration, it is possible to display more unique colors, to improve the design of the display body, and to realize a higher anti-counterfeit effect.

  The light reflecting layer provided between the relief structure forming layer and the light transmissive resin layer contributes to more strongly reflecting incident light. The light reflecting layer has a structure in which a metal such as aluminum, gold or silver, or a dielectric such as zinc sulfide or titanium oxide is provided in a single layer or a multilayer structure. For example, a vapor deposition method such as vacuum evaporation or sputtering. It is a thin film layer formed by. As shown in FIG. 17, the light reflecting layer 30 is configured to follow the shape of the concavo-convex structure provided in the relief structure forming layer 10, maintains the smoothness of the first surface 21 and the second surface 22, and It is desirable that the first surface 21 and the second surface 22 be configured not to impair that they are parallel to each other. FIG. 17 is a cross-sectional view showing an example of a preferable light reflecting layer.

  The surface of the light reflecting layer 30 is rough as shown in FIG. 18 and the smoothness of the first surface 21 and the second surface 22 is not maintained, or the light reflecting layer 30 is biased as shown in FIG. In the case of being stacked on the first surface 21 and the second surface 22, the light is weakened by interference, and the wavelength range of the light whose diffraction efficiency is lowered is widened. As a result, the display color is obtained. , The display color is close to white, which is not much different from the wavelength distribution of the incident light. 18 and 19 are cross-sectional views showing examples of undesirable light reflecting layers.

  Here, the film thickness of the light reflection layer is desirably 30 nm or more and 70 nm or less, and more preferably 50 nm. The light reflecting layer can be formed into a thin film by a vapor deposition method, but a metal such as aluminum, gold, or silver is likely to have a granular unevenness of about 1 μm on the surface of the film. This granular unevenness tends to enlarge as the deposited layer becomes thicker. On the other hand, if the deposited layer is too thin, sufficient light reflection performance cannot be obtained. The ideal film thickness of the light reflection layer obtained by experiment was 30 nm or more and 70 nm or less, and more preferably 50 nm. By setting the film thickness of the light reflecting layer in such a range, it is possible to obtain a light reflecting layer in which sufficient light reflecting performance is obtained and the smoothness of the first surface and the second surface is maintained.

  The difference in refractive index between the first resin region and the second resin region is preferably 0.15 or more. When the difference in refractive index is 0.15 or more, it is possible to obtain a sufficient difference in optical path difference with respect to the incidence of light from a white light source, and to display clearly different colors in each region. Become. Examples of the combination of resin materials that can provide a difference in refractive index of 0.15 or more include a combination of an epoxy resin (refractive index of approximately 1.6) and a fluorine resin (refractive index of approximately 1.4). .

  By using a transparent or translucent material as the material of the relief structure forming layer, this display body is not only from the light transmitting resin layer side (front side), but also from the relief structure forming layer side (back side). Can also be observed. The height difference between the first surface and the second surface constituting the plurality of convex portions provided in the relief structure forming layer is the same regardless of whether it is observed from the front surface side or from the back surface side. The color displayed is determined by the refractive index.

  Here, if the refractive index of the relief structure forming layer is substantially the same as the first resin region or the second resin region of the light transmissive resin layer, they display the same color. On the contrary, if the refractive index of the relief structure forming layer is different from that of the first resin region or the second resin region of the light transmissive resin layer, and preferably the difference in refractive index is 0.15 or more, the display body is moved to the surface side. It is also possible to display completely different colors when observed from the back and when observed from the back side. Such an expression method for displaying different colors on the front and back is not possible with a conventional diffraction grating pattern or ordinary printed matter, and in addition to a characteristic visual effect, the display body has a higher anti-counterfeit effect.

  When the display body is provided on a base material such as paper or plastic film, or other article, and the display body is observed from both the front and back surfaces, the base material or other article is provided with an opening, transparent or It is preferable to provide a configuration in which the display body can be observed by providing a window portion through which the display body that is translucent is visible.

(Optical properties of the third relief structure formation region)
Next, the optical properties of the third relief structure forming region will be described.

  The third relief structure formation region is a region having a different structure and optical properties from the first relief structure formation region and the second relief structure formation region. None of the third relief structure formation regions may exist in the display body, or a plurality of third relief structure formation regions may exist.

  As a structure that can be adopted in the third relief structure formation region, a diffraction grating can be cited. A diffraction grating is a regularly formed linear pattern with a typical pitch of 0.5 μm or more and 10 μm or less, which emits a rainbow-colored spectral color by diffraction, and the position of the light source and the observation angle of the observer For example, it is possible to realize a function of displaying an image whose color or pattern changes according to an observation condition or displaying a stereoscopic image.

  Another structure that can be employed in the third relief structure formation region is an antireflection structure having a very fine uneven structure. The antireflection structure 61 is typically a conical structure as shown in the perspective view of FIG. 20 or a structure in which pyramidal structures are regularly arranged, and the structure has a wavelength less than the wavelength of visible light (for example, The higher the structure height is 300 μm or more, the higher the antireflection effect is. The antireflection structure 61 formed with the specifications as described above has a function of preventing or reducing the reflection of incident visible light, and looks black or dark gray when observed.

  Moreover, as a structure employable in the third relief structure forming region, for example, a light scattering structure 62 shown in the perspective view of FIG. The light scattering structure 62 is typically a structure in which a plurality of irregular shapes having different sizes, shapes, and heights are irregularly arranged. The light incident on the light scattering structure 62 is irregularly reflected in all directions and appears white or cloudy when observed. Typically, many light scattering structures have a width of 3 μm or more and a height of 10 μm or more, and are larger than a diffraction grating or an antireflection structure. Moreover, the size, arrangement interval, and shape are not uniform. Therefore, the effect of scattering and reflecting white light can be obtained.

  The third relief structure forming region may be a flat surface. The third relief structure forming region is a flat surface, and acts as a mirror surface by the light reflecting layer. Moreover, it can also be set as a transparent or semi-transparent area | region by not providing a light reflection layer in a 3rd relief structure formation area.

  FIG. 22 is a cross-sectional view showing an example of a display body including the third relief structure forming region 13. As an example, a light scattering structure 62 is formed in the third relief structure forming region 13, and it is configured on one surface of the relief structure forming layer 10, similarly to the first relief structure forming region 11. The light transmissive resin layer 40 that covers the third relief structure formation region via the light reflection layer may be the first resin region 41 or the second resin region 42. The diffraction grating, the antireflection structure, the light scattering structure, and the flat surface exhibit their optical actions regardless of the refractive index of the light-transmitting resin layer 40 to be coated.

(How to use the display)
The display body mentioned above can be used, for example, as a label for preventing counterfeiting by being attached to a printed material or other articles via an adhesive material or the like. The display body can display a unique color by strictly controlling the flatness of the first and second surfaces of the convex or concave portions constituting the fine concavo-convex structure and the height difference between them, The color can be controlled by appropriately changing the refractive index of the light-transmitting resin layer (and the relief structure forming layer), and it is difficult to reproduce them with high accuracy, so counterfeiting is very difficult. When this label is supported on an article, it is also difficult to forge or imitate the genuine article with label.

  FIG. 23 is a plan view schematically showing an example of a labeled article that is supported on the article using a display body as a label for preventing counterfeiting. 24 is a cross-sectional view of the labeled article shown in FIG. 23 taken along line XXIIII-XXIIII.

  23 and 24, a printed matter 73 is illustrated as an example of an article with a label. The printed matter 73 is an IC (integrated circuit) card and includes a base material 72. The base material 72 is made of plastic, for example. A concave portion is provided on one main surface of the substrate 72, and the IC chip 71 is fitted in the concave portion. Electrodes are provided on the surface of the IC chip 71, and information can be written into the IC and information recorded in the IC can be read through these electrodes. A printed layer 70 is formed on the base material 72. The display body 1 mentioned above is being fixed to the surface in which the printing layer 70 of the base material 72 was formed through the adhesion layer, for example. The display body 1 is prepared as an adhesive sticker or a transfer foil, for example, and is fixed to the base material 72 by sticking it to the printing layer 70.

  This printed matter 73 includes the display body 1. Therefore, it is difficult to forge or imitate the same printed product 73. In addition, since the printed matter 73 further includes the IC chip 71 and the printed layer 70 in addition to the display body 1, it is possible to adopt anti-counterfeiting measures using them.

  23 and 24 illustrate an IC card as the printed material 73 including the display body 1, the printed material 73 including the display body 1 is not limited to this. For example, the printed matter 73 including the display body 1 may be another card such as a magnetic card, a wireless card, and an ID (identification) card. Alternatively, the printed matter 73 including the display body 1 may be securities such as gift certificates and stock certificates. Alternatively, the printed matter 73 including the display body 1 may be a tag to be attached to an article to be confirmed as an authentic product. Alternatively, the printed material 73 including the display body 1 may be a package body that contains an article to be confirmed to be genuine or a part thereof.

  Moreover, in the printed matter 73 shown in FIG.23 and FIG.24, although the display body 1 is affixed on the base material 72, the display body 1 can be supported on the base material 72 by another method. For example, when paper is used as the base material 72, the display body 1 may be rolled into the paper and the paper may be opened at a position corresponding to the display body 1.

  Moreover, the labeled article may not be a printed material. That is, the display body 1 may be supported on an article that does not include a printed layer. For example, the display body 1 may be supported by a luxury product such as a work of art.

  The display body 1 may be used for purposes other than forgery prevention. For example, the display body 1 can be used as a toy, a learning material, or a decoration.

  DESCRIPTION OF SYMBOLS 1 ... Display body, 10 ... Relief structure formation layer, 11 ... 1st relief structure formation area, 12 ... 2nd relief structure formation area, 13 ... 3rd relief structure formation area, 20 ... Convex part, 21 ... 1st surface, DESCRIPTION OF SYMBOLS 22 ... 2nd surface, 30 ... Light reflection layer, 40 ... Light transmissive resin layer, 41 ... 1st resin area, 42 ... 2nd resin area, 50 ... Partial area A50, 51 ... Partial area B, 52 ... Partial area C, 53 ... partial region D, 61 ... antireflection structure, 62 ... light scattering structure, 70 ... printed layer, 71 ... IC chip, 72 ... substrate, 73 ... printed matter, d ... pitch of diffraction grating, DL ... Diffraction light, DL_r ... Diffraction light (red), DL_g ... Diffraction light (green), DL_b ... Diffraction light (blue), GR ... Diffraction grating, IL ... Illumination light, LS ... Light source, NL ... Normal, RL ... 0Next time Folded light (regular reflected light), α ... incident angle, β_r ... emission angle of diffracted light of wavelength component R, β_g: the exit angle of the diffracted light of the wavelength component G, β_b: the exit angle of the diffracted light of the wavelength component B.

Claims (8)

A display body having a multilayer structure in which at least a relief structure forming layer, a light reflecting layer, and a light transmitting resin layer are laminated,
In the relief structure forming layer, a plurality of convex portions or concave portions including a first surface that is substantially parallel and smooth to the display surface of the display body and a second surface that is substantially parallel to the first surface are arranged in an orderly manner. The first relief structure forming region is formed by non-ordered arrangement, and the height difference between the first surface and the second surface constituting the convex portion or the concave portion is substantially constant,
The light reflecting layer is provided in at least a part between the relief structure forming layer and the light transmissive resin layer, and is a thin film formed following the shape of a plurality of convex portions or concave portions of the relief structure forming layer. Layer,
The display body, wherein the light transmissive resin layer includes a first resin region and a second resin region made of a transparent or translucent light transmissive resin having different refractive indexes with respect to visible light.   It further has a second relief structure forming region in which the height difference between the first surface and the second surface constituting the convex portion or the concave portion is substantially constant, and the height difference is different from the first relief structure forming region. The display body according to claim 1.   The display according to claim 2, wherein the first resin region and the second resin region, and the first relief structure forming region and the second relief structure forming region are partially overlapped with each other. body.   The display according to any one of claims 1 to 3, wherein the light reflecting layer has a single-layer or multi-layer structure of metal or dielectric, and has a layer thickness of 30 nm to 70 nm, preferably 50 nm. body.   The display body according to any one of claims 1 to 3, wherein a difference in refractive index between the first resin region and the second resin region is 0.15 or more.   6. The relief structure forming layer is made of a transparent or translucent light transmissive resin having a refractive index different from that of the first resin region and the second resin region. The display body according to item 1.   7. The relief structure forming layer further comprising a third relief structure forming region composed of any one of a diffraction grating, an antireflection structure, a light scattering structure, and a flat surface. The display body according to item 1.   8. A labeled article comprising the display body according to claim 1 and an article supporting the display body.

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