JP5776247B2 - Indicator - Google Patents

Description

  The present invention relates to a display technology that provides an anti-counterfeit effect.

  In general, in order to prevent forgery of securities, such as banknotes, gift certificates, and checks, as well as certificates such as passports and licenses, a display having a visual effect different from that of ordinary printed materials is pasted. It has been. 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, Non-Patent Document 1 describes the principle that incident light (white light) changes to a rainbow-colored spectral color by the diffraction grating.

  In a display body using a diffraction grating, a relief type diffraction grating formed with a plurality of grooves is generally used. A relief type diffraction grating is usually obtained by replicating an original plate produced using photolithography as a mother die. For example, Patent Document 1 and Patent Document 2 display a picture by appropriately changing the grating angle and the grating interval (grating pitch) of the diffraction grating by utilizing the spectral color that the diffraction grating shines in rainbow colors. Is described. In the display formed by a plurality of diffraction grating structures with different grating angles and intervals, the wavelength of the diffracted light that reaches the eyes of the observer gradually changes as the position of the observer and the position of the light source change. Thus, an image that changes to a rainbow color can be expressed.

  In addition, in these documents, 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. Non-Patent Document 2 describes a method of forming a diffraction grating using two-beam interference. In the manufacture of the relief type diffraction grating, the original stamp obtained in this way is usually used, and a metal stamper is produced 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 to a film or sheet-like thin transparent substrate 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 reflective layer is formed on a resin layer provided with a relief structure by depositing a metal such as aluminum or a dielectric 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.

JP-A-2-72320 US Pat. No. 5,058,992

Junhei Tsujiuchi “Holographic Display” Sangyo Tosho Co., Ltd. Junpei Takiuchi “Holography” Maruzen Co., Ltd.

  The present invention solves the above-described problems, and an object thereof is to provide a display body and a labeled article that exhibit a high anti-counterfeit effect.

  In order to achieve the above object, the first invention provides a base material, a light-transmitting release layer provided on one surface side of the base material, and a surface of the release layer opposite to the base material. Provided on the opposite side of the light-transmitting concavo-convex structure forming layer, the light reflecting layer covering at least a part of the concavo-convex structure forming layer, and the surface of the light reflecting layer provided with the concavo-convex structure forming layer. The concavo-convex structure forming layer includes a plurality of convex portions whose top surface is substantially parallel to the base material surface, or a plurality of concave portions whose bottom surface is substantially parallel to the base material surface. And at least one first region configured by arranging a flat portion substantially parallel to the substrate surface, and the plurality of convex portions or concave portions are arranged in an orderly manner in the first region. The length of the long side and the short side of the convex portion or the concave portion is 0.3 μm or more and 10 μm or less, respectively, and the convex portion Alternatively, the height of the recess is 0.1 μm or more and 0.5 μm or less, and the area occupied by the projection or recess in the first region is 20% or more and 80% or less. It is a display.

  According to a second aspect of the present invention, the adhesive layer of the display body according to claim 1 is brought into contact with the transfer target body and thermally transferred by heating and pressing, and the base material is bonded at the interface between the base material and the release layer. In the display body to be peeled off, the arithmetic average roughness Ra based on JIS B0601-1994 of the surface of the transferred body is more than 2.0 μm and not more than 10.0 μm, and the average interval of unevenness based on JIS B0601-1994 The display body is characterized in that Sm exceeds 130 μm and is 1300 μm or less, and the length of the long side and the short side of the convex portion or the concave portion is 0.3 μm or more and less than 1.5 μm, respectively.

  Moreover, 3rd invention is equipped with two or more said 1st area | regions, The length of the long side and short side of the said convex part or a recessed part is at least 1 area | region among the said 2 or more area | regions. Each of which is 1.5 μm or more and 10 μm or less, and in other regions, the lengths of the long side and the short side of the convex portion or the concave portion are 0.3 μm or more and less than 1.5 μm, respectively. A display body according to claim 2.

  According to a fourth aspect of the present invention, the adhesive layer of the display body according to claim 1 is thermally transferred by bringing the adhesive layer into contact with the transfer target body and applying heat and pressure, and the base material is bonded at the interface between the base material and the release layer. In the display body to be peeled off, the transferred object has two or more areas, and in at least one of the two or more areas, the arithmetic average roughness of the surface of the transferred object based on JIS B0601-1994 Ra is more than 2.0 μm and not more than 10.0 μm, and the average spacing Sm of the irregularities based on JIS B0601-1994 is more than 130 μm and not more than 1300 μm, and in other regions, the transferred object The arithmetic average roughness Ra based on JIS B0601-1994 is greater than 0.02 μm and not more than 2.0 μm, and the average spacing S of irregularities based on JIS B0601-1994 There is a display body which is characterized in that less and 1300μm exceed 130 .mu.m.

  According to a fifth aspect of the present invention, at least one of a diffraction grating, an antireflection structure, a light scattering structure, and a flat portion is formed in a second region that differs in structure and optical properties from the first region. The display body according to claim 1, wherein the display body is a display body.

  According to the first aspect of the present invention, according to the first invention, the plurality of convex portions whose upper surface is substantially parallel to the base material surface, or the plurality of concave portions whose bottom surface is substantially parallel to the base material surface, and the base material surface A display body capable of displaying colors composed of light of a plurality of wavelengths according to the incidence of illumination light is obtained by the first region configured by arranging flat portions substantially parallel to the light. Unlike the relief-type diffraction grating pattern, this display body does not change its color to iridescent according to changes in the position of the illumination or the position of the observer, and is different from the conventional anti-counterfeit medium using a diffraction grating. The effect can be realized. As a result, a display body that exhibits a high anti-counterfeit effect can be obtained.

  In addition, according to the second invention, the transferred object having a large surface roughness, the length of the long side and the short side of the convex portion or the concave portion is set to 0.3 μm or more and less than 1.5 μm, respectively. It is difficult to confirm the roughness of the surface when the image is observed, and a visual effect different from that of a normal printed matter or a diffraction grating pattern can be realized. As a result, a display body that exhibits a high anti-counterfeit effect can be obtained.

  According to the third aspect of the invention, there are two or more first regions, and the lengths of the long side and the short side of the convex portion or the concave portion are 1.5 μm or more and 10 μm or less, respectively, in at least one region. Yes, in other areas, the length of the long side and the short side of the convex part or the concave part is 0.3 μm or more and less than 1.5 μm, respectively, and by forming a latent image pattern as a display image by these areas, the surface A display body in which a latent image pattern is perceived under a specific illumination condition can be obtained by the area where the roughness can be confirmed and the area where the roughness cannot be confirmed.

  According to the fourth invention, the surface of the transfer object having two or more regions having different surface roughnesses in these regions, and forming a latent image pattern as a display image from these regions, the surface roughness can be confirmed. By the region that cannot be confirmed, a display body in which a latent image pattern is perceived under a specific illumination condition can be obtained.

  According to the fifth invention, the design of the display body is further enhanced by providing the display body with a second region comprising any one of a diffraction grating, an antireflection structure, a light scattering structure, and a flat portion. As well as a higher anti-counterfeit effect.

The top view which showed roughly the display body which concerns on embodiment of this invention. The expanded sectional view of the display body which follows the II-II line of FIG. The expanded sectional view which shows the structural example which transcribe | transferred the transfer foil of FIG. 2 to the to-be-transferred body. The figure which showed roughly a mode that the diffraction grating with a narrow pitch inject | emits + 1st-order diffracted light. The figure which showed roughly a mode that the diffraction grating with a wide pitch inject | emits + 1st-order diffracted light. The top view which shows an example of the structure which can be employ | adopted as the 1st area | region of the display body which concerns on embodiment of this invention. The expanded sectional view of the display body which follows the III-III line of FIG. Schematic which shows the mode of the diffracted light inject | emitted from a diffraction grating. The figure which shows the mode of the diffracted light inject | emitted from the 1st area | region. Sectional drawing which shows an example of the diffraction grating whose top part and bottom part are not flat. Sectional drawing which shows another example of the diffraction grating whose top part and bottom part are not flat. Schematic which shows arithmetic mean roughness Ra of surface roughness. Schematic which shows the average space | interval Sm of the unevenness | corrugation of surface roughness. The expanded sectional view which shows an example which transcribe | transferred the display body of this invention to the to-be-transferred body. The expanded sectional view which shows another example which transcribe | transferred the display body of this invention to the to-be-transferred body. The expanded sectional view which shows another example which transcribe | transferred the display body of this invention to the to-be-transferred body. The perspective view which shows an example of the reflection preventing structure which is a structure employable as the 2nd area | region of a display body. The perspective view which shows an example of the light-scattering structure which is a structure employable as the 2nd area | region of a display body.

  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.

  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. The display body 1 includes a laminate of a base material 20, a release layer 21, a light transmission layer 22, a light reflection layer 23, and an adhesive layer 24. In this example, the light transmission layer 22 is an uneven structure forming layer. In the example shown in FIG. 2, the display body 1 shows a state of the transfer foil before being transferred to the transfer target.

  Further, the light reflection layer 23 may not be provided partially, and the reflection layer 23 is not provided in the region 13.

  The base material 20 is a resin film or a sheet, for example. The support 12 is made of a material having excellent heat resistance such as polyethylene terephthalate. A release layer containing, for example, a fluororesin or a silicone resin may be provided on the main surface supporting the release layer 21 of the substrate 20 instead of the release layer 21. Further, the base material 20 may be light transmissive or may not transmit light.

  The release layer 21 is formed on the substrate 20. The release layer 21 plays a role of stabilizing the release from the substrate 20 by the concavo-convex structure forming layer of the light transmission layer 22. The release layer 21 has light transparency and is typically transparent. The release layer 21 is made of, for example, a thermoplastic resin.

  As the light reflecting layer 23, 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 having a refractive index different from that of the light transmission layer 22 may be used as the light reflection layer 23. Alternatively, as the light reflecting layer 23, a laminated body of dielectric layers having different refractive indexes between adjacent ones, that is, a dielectric multilayer film may be used.

  Of the dielectric layers included in the dielectric multilayer film, those in contact with the light transmission layer 22 preferably have a refractive index different from that of the light transmission layer 22. The light reflecting layer 23 can be formed by, for example, a vapor deposition method such as a vacuum evaporation method or a sputtering method.

  As a method of not providing the light reflecting layer partially, after providing the light reflecting layer by a vapor deposition method, only a specific part is dissolved by a chemical or the like, or the light reflecting layer and the light transmitting resin are dissolved. There is a method of peeling a light reflecting layer of a specific portion with an adhesive material having an adhesive strength stronger than the adhesive strength with the layer. In addition, a method of preventing a light reflection layer from being formed by providing a barrier on the front surface of the light transmissive resin layer before performing the vapor deposition method is also used.

  In the display 1 shown in FIGS. 1, 2 and 3, the surface of the light transmission layer 22 has a plurality of protrusions whose upper surface is substantially parallel to the substrate surface, or the bottom surface is substantially parallel to the substrate surface. And a plurality of concave portions and at least one first region configured by arranging a flat portion substantially parallel to the base material surface. In these drawings, the first region 14 is a region where minute irregularities are formed, and the second region 15 is defined as a region having a structure and optical properties different from those of the first region 14. . The second region 15 may be a region where an uneven structure different from that of the first region 14 is formed, or may be a region formed of a flat surface where no structure is formed. In addition, at least one or more first regions 14 are present in the display body 1, but a plurality of second regions 15 may be present in the display body 1 or none may be present. . A plurality of regions having different structures may be combined to form a display body.

  As a material of the light transmission layer 22, for example, a resin having a light transmission property such as a thermoplastic resin or a photocurable resin can be used. When a thermoplastic resin or a photo-curing resin is used, for example, a light transmitting layer 22 having a convex portion or a concave portion provided on one main surface is transferred from a metal stamper on which a convex portion or a concave portion of the display body is formed. Can be molded.

  FIG. 3 is an enlarged cross-sectional view illustrating a configuration example in which the transfer foil illustrated in FIG. 2 is transferred to a transfer target.

The transferred object 30 and the adhesive layer 24 are brought into close contact with each other, and heat and pressure are applied from the substrate 20 side to bond them. Thereafter, the display body 1 is transferred to the transfer target 30 by peeling the substrate 20 at the interface with the release layer 21.

  Examples of the material of the transfer target 30 include paper, PET, and polycarbonate (PC).

The surface of the transfer target 30 has a concavo-convex structure 31. The concavo-convex structure 31 may be a concavo-convex structure originally possessed by very general paper. When the transfer target 30 is PET, polycarbonate, or the like, the concavo-convex structure 31 may be formed by embossing or the like. .

(Description of the first area)
In describing the first region according to the present invention, first, the relationship between the pitch of the diffraction grating and the wavelength of the illumination light, and the illumination light incident angle and the emission angle of the diffracted light will be described.

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

The exit angle β of the m-th order diffracted light (m = 0, ± 1, ± 2,...) can be calculated from the following formula 1 when the light travels in a plane perpendicular to the grating line of the diffraction grating. it can.

  In Equation 1, d represents the grating constant (grating period, pitch) of the diffraction grating, m represents the diffraction order, and λ represents the wavelength 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. 4 shows the relationship between the illumination light incident angle and the emission angle of the + 1st order diffracted light with respect to the diffraction grating having the pitch d. When the illumination light is white light including a plurality of wavelength components, the exit angle of the diffracted light varies depending on the wavelength. As a result, when the diffraction grating is observed under a white illumination light source such as the sun or a fluorescent lamp, white light is dispersed, and light of a single wavelength is emitted at different angles.

  In FIG. 4, white light IL (here, it is assumed that the wavelength components constituting the white light are three wavelengths of R, G, and B) are incident from the point light source LS, and the diffracted light of the wavelength component R by the diffraction grating GR. It shows a state where light is split into DL_r, diffracted light DL_g of wavelength component G, and diffracted light DL_b of wavelength component B. At this time, the exit angle β_r of the diffracted light of the wavelength component R, the exit angle β_g of the diffracted light of the wavelength component G, and the exit angle β_b of the diffracted light of the wavelength component B take different values for each wavelength (in FIG. , Only the exit angle of DL_r is described as β_r). Other orders of diffracted light are also emitted at angles derived from Equation 1, but are not shown in FIG.

  FIG. 5 is a diagram schematically showing a state in which the display of the present invention emits + 1st order diffracted light. When white light is incident on a diffraction grating having a wider pitch than that in FIG. A state of injection is schematically shown. When the pitch d is large, as is clear from Equation 1, the diffracted light is emitted in a direction closer to the specularly reflected light RL as compared with the diffraction grating having a narrow pitch, and the emission angles of the separated single-wavelength light beams. The difference between is small. As apparent from Equation 1, when the diffraction grating is in a medium having a constant refractive index distribution (for example, in the air), the exit angle of the diffracted light is the incident angle and wavelength of the incident illumination light, and the pitch of the diffraction grating. Uniquely determined by

  Next, the relationship between the pitch of the diffraction grating and 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.

Illumination light that is incident on the diffraction grating of pitch d at an incident angle of α emits diffracted light in the direction of angle β based on Equation 1. At this time, the emission intensity of the light having the wavelength λ, that is, the diffraction efficiency, varies depending on the pitch and height of the diffraction grating and is derived by Equation 2.

  Here, η is the diffraction efficiency (having a value of 0 to 1), r is the height of the diffraction grating, L is the grating line width of the diffraction grating, d is the pitch of the grating line, θ is the incident angle of the illumination light, λ Is the wavelength of incident light and diffracted light. Note that Equation 2 holds for a shallow rectangular diffraction grating having a concavo-convex structure.

  As is apparent from Equation 2, the diffraction efficiency varies depending on the height r of the diffraction grating, the pitch d of the grating lines, the incident angle θ of incident light, and the wavelength λ. In practice, the diffraction efficiency tends to gradually decrease as the diffraction order m becomes higher.

  Next, the structure and optical properties of the first region will be described.

  In the first region, a plurality of convex portions whose upper surface is substantially parallel to the base material surface or a plurality of concave portions whose bottom surface is substantially parallel to the base material surface, and a flat portion substantially parallel to the base material surface are arranged. The plurality of convex portions or concave portions have a long side and a short side length of 0.3 μm or more and 10 μm or less, respectively, and the height of the convex portion or the concave portion is 0.1 μm or more. And the convex portions or concave portions are arranged in an orderly or non-ordered manner, and the area occupied by the convex portions or concave portions in the region is 20% or more and 80% or less.

  Here, the longest part of a convex part or a recessed part is defined as a long side, and the shortest part is defined as a short side. In other words, the convex portion or the concave portion has a shape enclosed in a rectangle having sides of 0.3 μm or more and 10 μm or less. For example, when the convex portion has a perfect circle shape, the long side and the short side have the same value. In the case of an ellipse or a rectangle, the long axis side is the long side and the short axis side is the short side.

  FIG. 6 is a plan view showing an example of a structure that can be employed in the first region of the display body of the present invention, and is a partially enlarged plan view of the first region 14 provided on the display body 1 in FIG. It is. FIG. 7 is a cross-sectional view taken along line III-III in FIG. The circular convex portions 16 are regularly arranged in a predetermined direction (A, B, and C indicated by a one-dot chain line) in the first region 14.

  Note that the above-described orderly arrangement means that the convex portions or the convex portions are arranged at equal intervals or regularity, for example, a square lattice, a rectangular lattice, or a triangular lattice. By controlling the arrangement of these concave portions or convex portions, there is an advantage that diffracted light with less stray light can be obtained.

  As another example of the shape of the convex portion or the concave portion, an elliptical shape, an octagonal shape, a star shape, a polygonal shape such as a cross, etc. can be arbitrarily adopted. Moreover, the convex part or recessed part from which a shape differs may be mixed in the 1st area | region.

  FIG. 8 is a schematic diagram showing the state of diffracted light emitted from the diffraction grating. In the diffraction grating GR composed of a plurality of grating lines regularly formed in a direction parallel to the y-axis as shown in FIG. 8, 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. 9 is a schematic view showing the state of diffracted light emitted from a display body adopting the present invention, and is formed in the first region 14 when illumination light enters the structure as shown in FIG. Diffracted light is emitted by the concavo-convex structure with periodicity formed by the plurality of convex portions 16 and the surrounding flat portions 17. As shown in FIG. 6, in the structure in which the convex portions 16 are regularly arranged in the first region 14 so as to be separated from each other, the diffracted light is not limited to the x-axis direction but is diffracted with respect to many azimuth angles on the XY plane. It is injected. The diffracted light emitted here is diffracted light DL_r having a long wavelength on the side closer to the incident light, as in the case where the light is incident on the diffraction grating as shown in FIG. DL_g and further DL_b are emitted in the direction of moving away. Although FIG. 9 illustrates a state where light is incident on one point of the first region, actually, light is incident on the first region in a planar shape, not incident on one point.

  The plurality of convex portions 16 are regularly arranged in the first region 14 so as not to contact each other. In FIG. 6, the diameter of the convex part 16 shall be about 1 micrometer. Here, considering the directions indicated by the one-dot chain line A and one-dot chain line B in FIG. 6, it can be considered that a diffraction structure having a pitch of about 1.4 μm is formed by the plurality of convex portions 16. Here, assuming that the white illumination light source is provided vertically above the display body, and the white illumination light is incident on the surface of the display body from the vertical (incident angle α = 0 °) direction, for example, white Of the illumination light, light having a wavelength of 630 nm is emitted as + 1st order diffracted light at an angle β≈26.7 ° according to Equation 1. Further, light having a wavelength of 540 nm has an angle of 22.7 °, and light having a wavelength of 460 nm has an angle of 19.2 °. Also in other directions (for example, the alternate long and short dash line C), diffracted light is emitted based on Equation 1 due to the periodicity of the plurality of convex portions 16. In general, since an illumination light source such as the sun or a fluorescent lamp has a certain area, light is incident on the diffractive structure from an oblique direction. For example, if light from a white illumination light source enters the diffraction structure from an angle of α = 1.0 °, the + 1st order diffracted light has an angle β≈25.7 ° of light with a wavelength of 630 nm and an angle β of light with a wavelength of 540 nm, respectively. Light having a wavelength of approximately 21.6 ° and a wavelength of 460 nm is emitted in the direction of an angle β≈18.2 °.

  In other words, since the illumination light source that is actually the incident light usually has a certain area, the light observed by the observer at a fixed point is a combination of light of a certain range of wavelengths, and as a result, light of multiple wavelengths. The color due to will be observed.

  In this way, the conditions under which the light from the illumination light source is incident on the surface of the display body, the incident light is diffracted by the concavo-convex structure forming layer of the display body, and the observer can perceive the light visually are described as `` normal illumination conditions It is defined as “below”. 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, The condition under which the light from the illumination light is incident on the surface of the display body under illumination light such as sunlight outside the room substantially vertically and the observer observes the display body is `` normal illumination conditions Is equivalent to. Here, “normal illumination light” refers to illumination light such as an indoor fluorescent lamp or outdoor sunlight.

  “Conditions other than normal illumination conditions” indicate conditions under which the observer cannot perceive diffracted light. For example, the condition that the light from the illumination light is incident on the surface of the display body substantially horizontally, that is, at a steep angle, and the diffracted light is not emitted from the uneven structure forming layer of the display body, or the uneven structure forming layer of the display body Even if the diffracted light is emitted from, the condition that 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”.

  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 line are constant, the diffraction efficiency η corresponds to the height r of the diffraction grating (corresponding to the height of the convex part or the depth of the concave part) and the illumination light. Is uniquely determined by the wavelength λ.

  For this reason, when the display body (first region) 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 provided in the first region (or the depth of the concave portion). The diffraction efficiency of light having a specific wavelength is reduced according to the above, and as a result, the light reaching the observer becomes light in which the specific wavelength component of the incident white illumination light is weakened. Therefore, when the observer observes the first region, he / she perceives light having a plurality of wavelengths having different light amounts. For each of the plurality of first regions provided on the display body, a different color is displayed when the respective regions are observed by forming convex portions (or concave portions) at different heights (or depths). It becomes possible.

  For example, when observing a first 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 reaching the eyes of the observer is red. (Wavelength 630 nm) and green (wavelength 540 nm), the observed color is yellow, and the red wavelength when observing another first region provided with a convex portion of another height If the diffraction efficiency of the component light is weakened 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).

  These colors cannot be 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 perceived and a state where the display color cannot be perceived 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.

  Conventional display devices using a diffraction grating for the purpose of preventing counterfeiting do not have sufficient processing accuracy of the diffraction grating, and do not have an ideal rectangular cross-sectional shape as shown in FIG. 2, FIG. 3, or FIG. In general, the cross-sectional shape is sinusoidal as shown in the cross-sectional view of FIG. 10, or the top portion or the flat portion of the convex structure is bumpy as shown in the cross-sectional view of FIG. Therefore, it becomes difficult for the diffraction efficiency to change according to the height (depth) of the structure for each wavelength as shown in Equation 2. In other words, since the difference in the diffraction efficiency of each wavelength is reduced, the light reaching the fixed point where the observer is located reaches all the wavelengths of light emitted from the white illumination light source, and the observer reaches The perceivable color is close to white and it becomes difficult to display a highly saturated color. For example, when white illumination light is incident on a minute concavo-convex structure such as a so-called frosted glass, which is not uniform in height and shape, the light is scattered and perceived as white.

  On the other hand, in the structure adopted in the first region of the present invention, the height of the convex portion (or the depth of the concave portion) is substantially the same in one first region and is substantially parallel to the substrate surface. Therefore, since it has an effect of preventing the diffraction efficiency of light of a specific wavelength from being lowered and reducing the diffraction efficiency of light of another specific wavelength, it is possible to display a highly saturated color.

  In addition, since the structure employed in the first region of the present invention emits diffracted light with respect to many azimuth angles on the XY plane as shown in FIG. 9, the position of the light source and the observation direction are somewhat Even if it changes, a color composed of a plurality of wavelengths can be observed. For this reason, it is possible to avoid or reduce the phenomenon that the display color changes to iridescent as in the conventional diffraction grating.

FIG. 12 is a schematic diagram showing the arithmetic average roughness Ra of the surface roughness. According to JIS B0601-1994, Ra is an average of absolute values of Z (x) at the reference length lr, and is calculated by Expression 3.

FIG. 13 is a schematic diagram showing the average interval Sm of the surface roughness irregularities. According to JIS B0601-1994, Sm is an average of the lengths Xs of the contour curve elements at the reference length lr, and is calculated by Expression 4 as a lateral parameter of the concavo-convex structure 31 of the transfer body 30.

Next, FIG. 14 is an enlarged cross-sectional view showing an example in which the display body of the present invention is transferred to a transfer target.
The uneven structure 31 is displayed by enlarging the surface shape of the transfer target 30. Here, an adhesive layer 24, a light reflection layer 23, a light transmission layer 22, and a release layer 21 are laminated on the transfer target 30. That is, the display body 1 is transferred by the adhesive layer 24.

  Here, the arithmetic average roughness Ra of the concavo-convex structure 31 of the transfer body 30 based on JIS B0601-1994 is 3.3 μm, and the average interval Sm of concavo-convex is 390 μm. The light transmission layer 22 includes a plurality of convex portions whose upper surfaces are substantially parallel to the base material surface or a plurality of concave portions whose bottom surfaces are substantially parallel to the base material surface, and a flat surface substantially parallel to the base material surface. Here, the concavo-convex structure 32 composed of the plurality of convex portions or concave portions has a long side and a short side length of 1 μm, respectively.

  By the way, the surface of the light reflecting layer 23 that contributes to the emission of the diffracted light and the uneven structure 32 of the light transmission layer 22 is not a flat surface due to the influence of the uneven structure 31 of the transfer target 30 due to the transfer. It becomes the shape along. Since the light reflection layer 23 is very thin, the light reflection layer 23 is almost the same as the shape of the light transmission layer 22. Here, when the surface roughness of the concavo-convex structure 31 is small, the influence is small, and the surface provided with the concavo-convex structure 32 of the light transmission layer 22 has a shape close to a plane.

  Here, when the lengths of the long side and the short side of the concavo-convex structure 32 are sufficiently small, even when the concavo-convex structure 32 is affected by the concavo-convex structure 31 of the transfer target 30, the diffracted light is observed. It becomes difficult to check the roughness of the surface, and when the lengths of the long side and the short side of the concavo-convex structure 32 are large, it becomes easy to check the surface roughness when diffracted light of the concavo-convex structure 32 is observed.

  Convex portion when the arithmetic average roughness Ra exceeds 2.0 μm and 10.0 μm or less based on JIS B0601-1994 on the surface of the transferred body, and the average interval Sm between the irregularities exceeds 130 μm and is 1300 μm or less Or, when the length of the long side and the short side of the recess is 0.3 μm or more and less than 1.5 μm, respectively, it is difficult to confirm the roughness of the surface when diffracted light is observed. When the thickness is 1.5 μm or more and 10 μm or less, it is easy to confirm the surface roughness when diffracted light is observed.

  Under the conditions shown in FIG. 14, it is difficult to confirm the roughness of the surface when diffracted light of the concavo-convex structure 32 is observed, and it is difficult to be influenced by the concavo-convex structure 31 of the transfer target 30, and a normal printed matter or diffraction grating pattern is used. Different visual effects can be achieved. As a result, a display body that exhibits a high anti-counterfeit effect can be obtained.

  By the way, a structure in which a plurality of convex portions whose top surface is substantially parallel to the base material surface or a plurality of concave portions whose bottom surface is substantially parallel to the base material surface and a flat portion substantially parallel to the base material surface is arranged. In order to make it possible to observe a color composed of light of a plurality of wavelengths, it is better to use a slightly larger structure of about 1.5 to 10 μm in the case of an ordered arrangement. 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 apparent from Equation 1, even if the position of the illumination light source or the observer changes, the display color does not change to a so-called rainbow color. Colors with multiple wavelengths can be observed stably. However, the influence of the surface roughness of the transfer target is increased.

  On the other hand, when the convex portion or the concave portion is a slightly smaller structure of about 0.3 to 1.5 μm and a small structure is formed with a small arrangement interval, the emission angle of the diffracted light is large as apparent from Equation 1. Become. Therefore, although it is easy to change the color to rainbow, light of a plurality of wavelengths can easily reach a fixed point where the observer is present. Further, there is an advantage that display colors by a plurality of lights can be observed in a wide range. For this reason, it becomes difficult to be affected by the surface roughness of the transfer target.

  The length of one side of the first region is preferably 300 μm or less. By arranging the first regions having a side length of 300 μm or less in an orderly manner, the shape of each first region can be prevented from being recognized when the display body is observed with the naked eye, and the resolution is improved. A high-definition image can be expressed. Here, the one side of the first region indicates the side of the maximum length of the first region.

  The lengths of the long side and the short side of the convex portion or the concave portion that can be employed in the first region are 0.3 μm or more and 10 μm or less, respectively. Visible light can be sufficiently diffracted if the structure has a size in this range. When it is smaller than 0.3 μm, processing becomes difficult and it becomes difficult to emit visible light, so that it easily functions as an antireflection structure. On the other hand, if it is larger than 10 μm, it is difficult to diffract, and at the same time, diffracted light is emitted near the direction in which the illumination light is incident.

  Moreover, it is preferable that the occupied area of the convex part or the concave part in the first region is 20% or more and 80% or less. From Equation 2, the diffraction efficiency η is highest when the width of the convex or concave portion (corresponding to the lattice line width L of Equation 2) is half of the pitch d. Therefore, the brightest display image can be obtained when the area occupied by the convex portion or the concave portion is about 50%, and it is most desirable. If it is about 20% or more and 80% or less, the diffraction efficiency decreases as the distance from 50% increases. Although the image becomes dark, it is possible to visually recognize a display image composed of light of a plurality of wavelengths. Note that the diffraction efficiency when the occupied area is 20% and 80% is about 30% of the brightness of 50% from Equation 2.

  If the area occupied by the protrusions or recesses is less than 20% or greater than 80%, sufficient brightness cannot be obtained, and it becomes difficult to obtain a sufficient eye-catching effect.

  Moreover, it is preferable that the height of a convex part or the depth of a recessed part is the range of 0.1 micrometer or more and 0.5 micrometer or less. In Formula 2, assuming that the pitch d and the grating line width L are constant, when the light having a wavelength in the visible light range is incident at an incident angle θ (a range greater than 0 ° and less than 90 °), the diffraction efficiency is highest. The value of the height of the convex part or the depth of the concave part is in the range of 0.1 μm to 0.5 μm. Note that, from Equation 2, the conditions for the highest diffraction efficiency are repeated even when the diffraction efficiency is larger than that, but for manufacturing, it is easier to manufacture when the height of the convex portion or the depth of the concave portion is as shallow as possible. Therefore, the conditions of 0.1 μm or more and 0.5 μm or less that can obtain high diffraction efficiency at a shallower value are desirable.

  If the height of the convex part or the depth of the concave part is less than 0.1 μm, the quality is stable and stable due to external factors during manufacturing (changes in machine and environmental conditions, slight changes in material composition, etc.) It is difficult to manufacture a thin structure, and when it is deeper than 0.5 μm, it becomes difficult to precisely transfer and mold a fine and deep structure.

Next, FIG. 15 is an enlarged cross-sectional view showing another example in which the display body of the present invention is transferred to a transfer target.
As in FIG. 14, the adhesive layer 24, the light reflection layer 23, the light transmission layer 22, and the release layer 21 are laminated on the transfer target 30. Here, the arithmetic average roughness Ra of the concavo-convex structure 31 of the transfer body 30 based on JIS B0601-1994 is 3.3 μm, and the average interval Sm of concavo-convex is 390 μm. Further, the light transmission layer 22 is divided into a region 35 and a region 36, and the concavo-convex structure 33 and the concavo-convex structure 34 in each region have different long and short sides, and the concavo-convex structure 33 is 1 μm. 34 is 2 μm.

  Therefore, it is difficult to confirm the roughness of the surface when the diffracted light of the concavo-convex structure 33 corresponding to the region 35 of the display body 1 shown in FIG. 15 is observed, and when the diffracted light of the concavo-convex structure 34 corresponding to the region 36 is observed. The roughness can be confirmed.

  Here, by forming characters and symbols using the region 35 and the region 36 and forming a latent image pattern as a display image, it cannot be confirmed when the diffracted light is not reproduced in a normal state. When observing with an illuminating light source that is reproduced, characters, symbols, and the like can be confirmed. Thereby, a display body in which a latent image pattern is perceived under a specific illumination condition can be obtained.

Next, FIG. 16 is an enlarged cross-sectional view showing still another example in which the display body of the present invention is transferred to a transfer target.
As in FIG. 15, the adhesive layer 24, the light reflection layer 23, the light transmission layer 22, and the release layer 21 are laminated on the transfer target 30. Here, the concavo-convex structure 31 of the transfer target 30 is divided into a region 38 and a region 39. The arithmetic average roughness Ra in the region 38 based on JIS B0601-1994 is 3.3 μm, and the average interval Sm of the concavo-convex is 390 μm. Yes, the arithmetic average roughness Ra based on JIS B0601-1994 in the region 39 is 0.5 μm, and the average interval Sm of the unevenness is 70 μm. Further, the length of the long side and the short side of the concavo-convex structure 37 of the light transmission layer 22 is 2 μm.

  For this reason, in the display body 1 shown in FIG. 16, it is difficult to confirm the roughness of the surface when diffracted light from the uneven structure 37 in the region 39 is observed, and the diffracted light from the uneven structure 37 in the region 38 is observed. Sometimes the roughness of the surface can be confirmed.

  Here, by forming characters and symbols using the region 38 and the region 39 and forming a latent image pattern as a display image, it is impossible to confirm when the diffracted light is not reproduced in a normal state. When observing with an illuminating light source that is reproduced, characters, symbols, and the like can be confirmed. Thereby, a display body in which a latent image pattern is perceived under a specific illumination condition can be obtained.

  As a method of changing the concavo-convex shape by providing a region on the transfer target 30, a plate obtained by patterning a convex portion on a metal plate is formed, and the shape of the convex portion is formed by heating and pressurizing the paper to be transferred. There is a method of flattening the surface of the paper.

  As another method, a screen printing method or the like is used to apply a resin to the paper to be transferred, and the pattern is applied and impregnated into the paper so that the uneven structure is filled, and the portion is flattened. There are various methods.

(Explanation of the second area)
Next, the second area will be described.
The second region 15 is a region that differs in structure and optical properties from the first region 14. The second region 15 may have a concavo-convex structure different from that of the first region 14, or may be a flat surface on which no structure is formed. A plurality of second regions 15 may exist in the display body 1.

  An example of a structure that can be used for the second region 15 is a diffraction grating. The diffraction grating is typically formed by repeatedly forming a linear concavo-convex structure (grating line) as shown in the perspective view of FIG. 8, with a pitch of about 0.5 to 1 μm and a structure height of 0. A typical specification is about 1 to 0.5 μm. The diffraction grating emits a rainbow-colored spectral color due to diffraction, and displays an image that changes in color and pattern according to the observation conditions such as the position of the light source and the observation angle of the observer, or displays a three-dimensional image Can do.

  Another structure that can be adopted for the second region 15 is an antireflection structure having a fine concavo-convex structure. The antireflection structure is typically an antireflection structure 18 having a conical structure as shown in the perspective view of FIG. 17 or a structure in which pyramidal structures are arranged in an orderly manner. The pitch is less than the wavelength of light (for example, 400 nm or less), and the height of the structure is 300 μm or more. The antireflection structure formed according to the specifications as described above has a function of preventing or reducing reflection of incident visible light, and looks black or dark gray when observed.

  Further, as a structure that can be employed in the second region 15, a light scattering structure can be cited. As shown in the perspective view of FIG. 18, the light scattering structure is typically one in which a plurality of light scattering structures 19 having irregular shapes having different sizes, shapes, and heights are irregularly arranged. The light incident on the light scattering structure 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 1 μm or more, and have a structure larger than that of a diffraction grating or an antireflection structure. Moreover, the size, arrangement interval, and shape are not uniform. Therefore, it is difficult for light to be diffracted or absorbed, and an effect of scattering light can be obtained.

  Further, the second region 15 may be a flat surface on which no concavo-convex structure is formed. When the second region 15 is a flat surface, the second region 15 looks like a mirror surface by the light reflecting layer 23.

  By combining the second region 15 and the first region 14, the design of the display body can be improved, and the effect of preventing forgery can be further improved. In the second region, a structure other than the above-described structure that exhibits optical characteristics different from those of the first region may be formed.

(Preparation method of display plate)
Next, a method for producing the original plate of the display body of the present invention will be described.
The original plate of the display body of the present invention can be produced by using a photolithography process in the same manner as a conventional relief diffraction grating production process. By exposing and developing a photosensitive resist applied substantially uniformly on a planar substrate (a glass substrate is generally used) by a charged particle beam such as an electron beam or a laser, a desired uneven shape is obtained. If the photosensitive resist is a positive resist, the portion irradiated with the charged particle beam dissolves after development, and if the photosensitive resist is a negative resist, the portion irradiated with the charged particle beam is developed after development. The remaining unirradiated part dissolves. The substrate is placed on an XY stage whose position can be adjusted with high accuracy, and the position where the charged particle beam is irradiated is determined while moving the stage under computer control.

  The substrate thus obtained has a concavo-convex structure made of a photosensitive resist and is not suitable as a stamper for mass production. Therefore, a metal stamper is produced from the substrate by using a method such as electroforming. . Electroforming is a type of surface treatment technology that forms a metal film by reducing the power of electrons by immersing an electroformed object in a predetermined aqueous solution and energizing it. By using such a method, The fine concavo-convex structure provided on the surface of the original plate can be transferred and molded as a metal plate with high accuracy. The surface of the object of electroforming needs to be able to be energized. Generally, the photosensitive resist does not conduct electricity. Therefore, before electroforming, metal is deposited on the surface of the structure by vapor deposition such as sputtering or vacuum evaporation. A thin film is provided in advance.

  Next, the concavo-convex structure is duplicated using this metal stamper as a matrix. That is, first, a thermoplastic resin or a photocurable resin is applied on a transparent substrate made of, for example, polycarbonate or polyester. 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 concavo-convex structure can be replicated by peeling the metal stamper from the cured resin.

  Generally, the base material and the resin material for formation are transparent. Therefore, normally, a reflective layer is formed on a resin layer (uneven structure forming layer) provided with an uneven structure by depositing a metal such as aluminum or a dielectric in a single layer or multiple layers by vapor deposition or the like. 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.

  As a method for producing the original plate, not only a photolithography process but also a process using a cutting tool such as a diamond tool having a fine tip, a process of corroding the surface of a metal or the like by etching, or the like can be employed. When such a method is used, it is possible to directly process the surface of the metal plate. In this case, the metal stamper can be obtained directly without creating a metal stamper by a method such as electroforming.

  In a method of processing a concavo-convex shape by irradiating a photosensitive resist coated on a substrate with a charged particle beam, a phenomenon called a proximity effect occurs. The proximity effect is a phenomenon in which the size and depth of the shape slightly change from the target size and depth depending on the size of the uneven shape to be processed and the ratio of the area irradiated with the beam per unit area. That's it. For example, even if a 0.5 mm square area is processed under the condition that a concave structure having a 1 mm square area and a depth of 0.1 mm can be processed with a certain amount of energy, a depth of 0.1 mm cannot be obtained. It becomes a slightly shallower concave structure. This is due to the phenomenon that the charged particle beam is scattered in the resist. This phenomenon is roughly divided into a phenomenon called forward scattering and a phenomenon called back scattering. The forward scattering occurs when the charged particle beam enters the resist, and the charged particle beam spreads, and the charged particle beam affects the area larger than the irradiated area. On the other hand, backscattering affects the photosensitive resist by a charged particle beam that passes through the photosensitive resist and is reflected by the front surface or the back surface of the substrate on the lower surface of the photosensitive resist. The influence of these scattered beams varies depending on the energy amount of the beam, the shape and depth of the pattern to be processed. The influence of the proximity effect also varies depending on the material composition of the photosensitive resist used and the applied film thickness.

  Therefore, when forming the convex portion or the concave portion provided in the first region on the original plate, the influence of the proximity effect changes depending on the area of the region, the size of the convex portion or the concave portion, the arrangement density, and the like. There is a possibility that a structure having a height (depth) may not be obtained. In the first area, the display color under normal illumination conditions is determined by the height (or depth) of the convex part (or concave part) provided in the first area, considering the influence of the proximity effect. It is necessary to process the structure with high accuracy.

  On the other hand, even if a third party uses a processing machine that uses a highly accurate charged particle beam, it is extremely difficult to forge an original plate having the same shape, and the same display color is obtained. It is difficult and the anti-counterfeiting effect is very high.

  As a processing machine using a charged particle beam, an electron beam drawing apparatus or a laser direct drawing apparatus is desirable. Since these apparatuses have a high processing speed and high position accuracy of the XY stage, it is possible to create a desired uneven pattern with high accuracy. Some have a function to make corrections based on experimental results so as to reduce the influence of the proximity effect. In order to obtain a desired display color, the structure employed in the first region needs to strictly control the height (depth), and these apparatuses can satisfy the requirement. Recent electron beam lithography equipment and laser direct lithography equipment have been improved in performance, and the stability of the charged particle beam to be radiated is high and the energy irradiation amount and energy density are almost the same with the same settings. There may be fluctuations due to slight changes in the usage environment (temperature, humidity, etc.) and the influence of device conditions (such as long-time operation). However, the amount of change is small, and when the same pattern is processed, the shape and depth of the processed pattern hardly change.

  On the other hand, it is possible to produce the original plate of the display body of this patent even by a method using processing or etching with a cutting device, but in that case, high processing accuracy is required, and selection of an appropriate material is important. . In addition to the fabrication of the structure of the first region, it is difficult to fabricate a diffraction grating that can be formed in the second region, an antireflection structure with a fine concavo-convex structure, a light scattering structure, etc. It is.

  DESCRIPTION OF SYMBOLS 1 ... Display body, 13, 14, 15 ... Area | region, 16 ... Convex part, 17 ... Flat part, 18 ... Antireflection structure, 19 ... Light-scattering structure, 20 ... Base material, 21 ... Release layer, 22 ... Light Transmission layer, 23 ... Light reflection layer, 24 ... Adhesive layer, 30 ... Transfer object, 31, 32, 33, 37 ... Uneven structure, 35, 36, 38, 39 ... region, d ... Pitch of diffraction grating, DL ... + 1st order diffracted light, DL_r ... + 1st order diffracted light (red), DL_g ... + 1st order diffracted light (green), DL_b ... + 1st order diffracted light (blue), GR ... diffraction grating, IL ... illumination light, LS ... light source, NL ... normal, RL: 0th-order diffracted light (regularly reflected light), α: incident angle, β: exit angle, β_r: exit angle of diffracted light of wavelength component R, β_g: exit angle of diffracted light of wavelength component G, β_b: wavelength component B Diffracted light emission angle, Ra ... arithmetic mean roughness, Sm ... concave / convex mean spacing, lr ... reference length

Claims (3)

A base material, and a light-transmitting release layer provided on one surface side of the base material;
A light-transmitting concavo-convex structure forming layer provided on the surface opposite to the substrate of the release layer;
A light reflecting layer covering at least a part of the concavo-convex structure forming layer;
A display body comprising an adhesive layer provided on the opposite side of the surface on which the uneven structure forming layer of the light reflecting layer is provided,
The concavo-convex structure forming layer includes a plurality of convex portions whose upper surface is substantially parallel to the base material surface, or a plurality of concave portions whose bottom surface is substantially parallel to the base material surface, and a flat portion substantially parallel to the base material surface. Comprising at least one first region configured by being arranged,
The plurality of protrusions or recesses are arranged in an orderly manner in the first region, and the lengths of the long sides and the short sides of the protrusions or recesses are 0.3 μm or more and 10 μm or less, respectively. The height of the recess is 0.1 μm or more and 0.5 μm or less, and the occupied area of the projection or recess in the first region is 20% or more and 80% or less,
The adhesive layer is brought into contact with a transfer target body, thermally transferred by heating and pressing, and the base material is peeled off at an interface between the base material and the release layer. The arithmetic average roughness Ra based on JIS B0601-1994 is more than 2.0 μm and not more than 10.0 μm, and the average interval Sm of unevenness based on JIS B0601-1994 is more than 130 μm and not more than 1300 μm,
Two or more first regions are provided, and in at least one of the two or more regions, the length of the long side and the short side of the convex portion or the concave portion is 1.5 μm or more and 10 μm or less In addition, in other regions, the lengths of the long side and the short side of the convex portion or the concave portion are 0.3 μm or more and less than 1.5 μm, respectively . A base material, and a light-transmitting release layer provided on one surface side of the base material;
A light-transmitting concavo-convex structure forming layer provided on the surface opposite to the substrate of the release layer;
A light reflecting layer covering at least a part of the concavo-convex structure forming layer;
A display body comprising an adhesive layer provided on the opposite side of the surface on which the uneven structure forming layer of the light reflecting layer is provided,
The concavo-convex structure forming layer includes a plurality of convex portions whose upper surface is substantially parallel to the base material surface, or a plurality of concave portions whose bottom surface is substantially parallel to the base material surface, and a flat portion substantially parallel to the base material surface. Comprising at least one first region configured by being arranged,
The plurality of protrusions or recesses are arranged in an orderly manner in the first region, and the lengths of the long sides and the short sides of the protrusions or recesses are 0.3 μm or more and 10 μm or less, respectively. The height of the recess is 0.1 μm or more and 0.5 μm or less, and the occupied area of the projection or recess in the first region is 20% or more and 80% or less,
The adhesive layer is brought into contact with a transfer target body, thermally transferred by heating and pressing, and the base material is peeled off at an interface between the base material and the release layer, wherein the transfer target body has a region. The arithmetic average roughness Ra based on JIS B0601-1994 of the surface of the transferred body is more than 2.0 μm and 10.0 μm or less in at least one of the two or more regions. And the average interval Sm of the irregularities based on JIS B0601-1994 is more than 130 μm and not more than 1300 μm, and the arithmetic average roughness based on JIS B0601-1994 of the surface of the transferred body in other regions Ra exceeds 0.02 μm and is 2.0 μm or less, and the average interval Sm between the irregularities based on JIS B0601-1994 exceeds 130 μm and 1300 μm or less. A display body characterized by being . Wherein said first region and structural and optical properties different from the second region, the diffraction grating, the anti-reflection structure, light scattering structures, and at least one is formed of the flat portion Item 3. The display according to item 1 or 2 .

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