JP5239509B2 - Optical element, labeled article and optical kit - Google Patents

Description

  The present invention relates to a display technology that provides, for example, an anti-counterfeit effect, a decorative effect, and / or an aesthetic effect.

  A latent image may be used to prevent forgery. The latent image can be formed using, for example, line moire or intaglio printing.

  A latent image using line moire is obtained by superimposing an image to be a latent image and a large number of lines arranged at high density. When this image is observed with the naked eye, many lines make it difficult to identify, and hiding these lines facilitates identification.

  A latent image using intaglio printing is obtained by providing a concave pattern and / or a convex pattern in the ink layer. The image formed by the concave pattern and / or the convex pattern is difficult to identify when viewed from the front, and is visualized by observing from an oblique direction.

  Forgery prevention technology using line moiré or intaglio printing is relatively easy to determine authenticity. However, images formed by these methods are not necessarily indistinguishable when observed with the naked eye. Therefore, these latent images are easy to realize their existence.

  The latent image can also be formed using special inks such as fluorescent ink and infrared absorbing ink. The fluorescent ink is an ink that emits light when irradiated with ultraviolet rays, and a latent image formed using the fluorescent ink is visualized when irradiated with ultraviolet rays. The infrared absorbing ink is an ink having a high infrared absorption rate, and a latent image formed using the infrared absorbing ink is visualized by observing with an infrared camera, for example.

  Latent images formed using special inks are difficult to realize. However, the visualization requires a device such as an ultraviolet lamp or an infrared camera.

  The latent image can also be formed using a liquid crystal material. For example, a thin film pattern made of a solidified liquid crystal material such as a polymer liquid crystal material is formed on a substrate having light reflectivity. The mesogens of the liquid crystal molecules are aligned in approximately one direction by, for example, performing an alignment process such as a rubbing process or a photo-alignment process on the base of the thin film pattern.

  The thin film pattern thus formed looks like an optically isotropic layer when observed with the naked eye. Therefore, a latent image can be formed with this thin film pattern. Since this thin film pattern functions as a retardation layer, when observed through a polarizer, a change in brightness according to the angle formed by the slow axis and the light transmission axis of the polarizer occurs. That is, the latent image formed by the thin film pattern is visualized by observing it through a polarizer.

  A latent image formed using a liquid crystal material is difficult to realize. In addition, the latent image can be visualized with a polarizer such as a polarizing film, and a large apparatus is not required. For this reason, anti-counterfeiting technology using a liquid crystal material has attracted high interest.

  By the way, a visual effect given by a latent image formed using a liquid crystal material cannot be perceived when observed with the naked eye. Therefore, many of the optical elements that form a latent image using a liquid crystal material further include a structure that gives a visual effect that can be perceived by the naked eye.

  For example, Patent Document 1 describes an optical element formed by laminating a latent image forming layer made of a polymer liquid crystal material and a reflection hologram. When this optical element is observed with the naked eye, a visual effect derived from a hologram can be perceived. When this optical element is observed through a polarizer, the visual effect derived from the hologram can be perceived, and the latent image formed in the latent image forming layer is visualized. Accordingly, this optical element provides an excellent decoration effect and / or aesthetic effect when observed with the naked eye, and also provides an excellent anti-counterfeit effect.

However, the combination of a hologram and a latent image formed using a liquid crystal material is already widely known. Therefore, a technique for providing a new visual effect is required.
JP 2001-63300 A

  An object of the present invention is to increase the variety of visual effects provided by an optical element including a solidified liquid crystal material.

According to the first aspect of the present invention, a light-scattering reflective layer, a liquid crystal layer made of a solidified liquid crystal material facing at least a part of one main surface of the reflective layer, and a part of the liquid crystal layer are interposed. Or a colored pattern layer facing a part of the main surface without sandwiching the liquid crystal layer therebetween, and the liquid crystal layer is adjacent to the in-plane direction, and the orientation direction or thickness of the mesogen Includes a plurality of liquid crystal portions different from each other, and when viewed with the naked eye, the first display portion corresponding to the colored pattern layer looks different from the first display portion and has a specific observation direction via a polarizer. An optical element is provided that includes a second display portion that looks the same color as the first display portion when viewed from above .

  According to a second aspect of the present invention, there is provided a labeled article characterized by including the optical element according to the first aspect and an article supporting the optical element.

  According to the 3rd side surface of this invention, the optical kit characterized by including the optical element and polarizer which concern on a 1st side surface is provided.

  According to the present invention, it is possible to increase the variety of visual effects provided by an optical element including a solidified liquid crystal material.

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

  FIG. 1 is a plan view schematically showing an optical element according to the first embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II of the optical element shown in FIG. FIG. 3 is a sectional view taken along line III-III of the optical element shown in FIG. 1 to 3, the X direction is a direction parallel to the main surface of the optical element 10, the Y direction is a direction parallel to the main surface of the optical element 10 and perpendicular to the X direction, The Z direction is a direction perpendicular to the X direction and the Y direction.

  The optical element 10 is, for example, a display body that is supported by an article to be confirmed to be a genuine product. The optical element 10 includes a substrate 11, a reflective layer 12, an intermediate layer 13, a liquid crystal layer 14, an anchor layer 15, and a colored pattern layer 16. The front surface of the optical element 10 is a surface on the colored pattern layer 16 side.

  The base material 11 is, for example, a film or sheet made of a resin such as a polyethylene terephthalate (PET) film. The substrate 11 may or may not have light transmittance. Moreover, the base material 11 may have a single layer structure, and may have a multilayer structure. The substrate 11 can be omitted.

  The reflective layer 12 is a reflective layer having light scattering properties. The reflective layer 12 covers the entire front surface of the substrate 11. The reflective layer 12 may cover only a part of the front surface of the substrate 11. Alternatively, the reflective layer 12 may at least partially cover the back surface of the substrate 11. In this case, the base material 11 is light transmissive at at least a part of the position corresponding to the reflective layer 12. Typically, the substrate 11 is transparent at least at a part of the position corresponding to the reflective layer 12.

  The reflective layer 12 includes a metal reflective surface. The reflective layer 12 is a layer formed by dispersing, for example, strips made of a metal such as aluminum in a resin.

  As this metal strip, for example, an aluminum paste containing aluminum processed into flakes as a pigment can be used. Aluminum paste includes a leafing type and a non-leafing type. When a leafing type aluminum paste is used, a reflective layer having a glossy surface close to specular reflection is obtained by arranging aluminum flakes parallel to the film surface in the surface region. When a non-leafing type aluminum paste is used, aluminum flakes are uniformly dispersed in the coating film, and a reflection layer having a scattering reflection surface is obtained. Here, it is desirable to use a non-leafing type capable of obtaining a scattering reflection surface. In addition, it is also possible to use the strip which consists of metals or alloys other than aluminum, such as silver and stainless steel, as a metal strip.

  The resin that can be included in the reflective layer 12 is light transmissive and typically transparent. As a material of this resin, for example, a thermoplastic resin can be used. As this resin or its material, for example, an acrylic resin, a urethane resin, an epoxy resin, a polyester resin, or a vinyl resin can be used alone or in combination.

  Here, as an example, the reflective layer 12 is formed by dispersing aluminum strips in a resin and covering the entire front surface of the substrate 11. Such a reflective layer 12 has light scattering properties because the aluminum strips diffusely reflect incident light in various directions.

  The liquid crystal layer 14 faces the front surface of the reflective layer 12. The liquid crystal layer 14 is formed by solidifying a liquid crystal material. Typically, the liquid crystal layer 14 is a polymer birefringent layer formed by curing a polymerizable liquid crystal material having fluidity with ultraviolet rays or heat.

  The liquid crystal layer 14 includes a plurality of liquid crystal portions 142 to 144 having different mesogen alignment directions. Here, as an example, it is assumed that the orientation direction of the mesogen is substantially parallel to the X direction in the liquid crystal portion 142 and substantially parallel to the Y direction in the liquid crystal portion 143. Here, in the liquid crystal portion 144, it is assumed that the orientation direction of the mesogen is 45 degrees clockwise with respect to the X direction when the optical element 10 is viewed from the front side. The liquid crystal portions 142 to 144 form a latent image, and the latent image is visualized when observed through a polarizer. A method of forming a plurality of regions having different mesogen orientation directions and the visual effect of the latent image formed by these regions will be described later.

  The intermediate layer 13 is interposed between the reflective layer 12 and the liquid crystal layer 14. The intermediate layer 13 has optical transparency and is typically transparent. The intermediate layer 13 includes, for example, a resin. The intermediate layer 13 plays a role of improving the adhesion between the reflective layer 12 and the liquid crystal layer 14.

  As the material of the intermediate layer 13, for example, a resin such as a thermoplastic resin can be used. As the resin or the material included in the intermediate layer 13, for example, an acrylic resin, a urethane resin, an epoxy resin, a polyester resin, or a vinyl resin can be used alone or in combination.

  The intermediate layer 13 may have a single layer structure or a multilayer structure. The intermediate layer 13 can be omitted.

  The anchor layer 15 covers the front surface of the liquid crystal layer 14. The anchor layer 15 has optical transparency and is typically transparent. In this case, the anchor layer 15 may be colorless and transparent, or may be colored and transparent.

  The anchor layer 15 plays a role as a protective layer that makes it difficult to cause damage and light deterioration of the liquid crystal layer 14 and suppresses deterioration of an image displayed by the optical element 10. In addition, the anchor layer 15 plays a role of improving the adhesion of the ink used for the colored pattern layer 16 to the liquid crystal layer 14. The anchor layer 15 can be omitted.

  The anchor layer 15 is made of resin, for example. Examples of the material of the anchor layer 15 include thermoplastic resins such as acrylic resin, urethane resin, vinyl chloride resin-vinyl acetate copolymer resin, polyester resin, melamine resin, epoxy resin, polystyrene resin, and polyimide resin, and thermosetting resin. Or ultraviolet rays or electron beam curable resins can be used alone or in combination.

  The colored pattern layer 16 is formed on the anchor layer 15. The colored pattern layer 16 faces a part of the front surface of the reflective layer 12 with the anchor layer 15, the liquid crystal layer 14, and the intermediate layer 13 interposed therebetween. The colored pattern layer 16 may or may not have optical transparency.

  The colored pattern layer 16 plays a role of causing the optical element 10 to display a visible image or a part thereof that can be perceived when observed with the naked eye. Here, the optical element 10 displays the character string “TP” when observed with the naked eye. The visible image displayed on the optical element 10 using the colored pattern layer 16 may be a character string, a character, a symbol, a figure, or a combination thereof.

  As a material of the colored pattern layer 16, for example, ink can be used. As this ink, for example, letterpress printing ink, offset printing ink, screen printing ink, flexographic printing ink, ultraviolet curable ink, thermal transfer ink, ultraviolet absorbing ink, infrared absorbing ink or fluorescent ink may be used. it can. As this ink, an optically variable ink exhibiting a different hue depending on the observation angle, for example, OVI ink (Optically Variable Ink) or pearl ink may be used. When such an ink is used, a better anti-counterfeit effect, a decorative effect and / or an aesthetic effect can be achieved. Here, as an example, ultraviolet curable colored ink is used.

This display body 10 can be manufactured by the following method, for example.
FIG. 4 is a plan view schematically showing an intermediate product obtained in an example of a manufacturing process of the optical element shown in FIGS. 1 to 3. FIG. 5 is a cross-sectional view taken along line VV of the intermediate product shown in FIG.

  In manufacturing the optical element 10 shown in FIGS. 1 to 3, first, the intermediate product 20 shown in FIGS. 4 and 5 is manufactured. The intermediate product 20 includes a base material 21, an alignment layer 22, and a liquid crystal layer 14.

  In manufacturing the intermediate product 20, first, the base material 21 is prepared. The base material 21 is a film or sheet made of a resin such as PET, for example. The base material 21 may or may not have light transmittance. Moreover, the base material 21 may have a single layer structure or a multilayer structure.

  Next, the alignment layer 22 is formed on one main surface of the substrate 21. The surface of the alignment layer 22 includes regions A2 to A4. Regions A2 to A4 correspond to the liquid crystal portions 142 to 144, respectively.

  Each of the regions A2 to A4 is provided with a plurality of grooves that are aligned in the length direction and are adjacent to each other in a direction intersecting the length direction. In the region A2, the length direction of the groove is substantially parallel to the X direction. In the region A3, the length direction of the groove is substantially parallel to the Y direction. In the region A4, the groove length direction forms an angle of 45 ° counterclockwise with respect to the X direction when the intermediate product 20 is viewed from the liquid crystal layer 14 side. When such a groove is provided, as will be described in detail later, a liquid crystal layer 14 in which mesogens are aligned along the length direction of the groove is obtained.

Here, a structure that can be employed for the alignment layer 22 and a method for forming the structure will be described in detail.
FIG. 6 is a plan view schematically showing an example of a structure that can be employed on the surface of the alignment layer. FIG. 7 is a plan view schematically showing another example of a structure that can be employed on the surface of the alignment layer. FIG. 8 is a plan view schematically showing still another example of a structure that can be employed on the surface of the alignment layer. FIG. 9 is a plan view schematically showing still another example of a structure that can be employed on the surface of the alignment layer.

  For each of the regions A2 to A4, for example, as shown in FIG. 6, a structure in which a plurality of grooves are arranged in parallel at equal intervals in the width direction can be adopted.

  These grooves may not be parallel to each other as shown in FIG. However, the closer these grooves are to be parallel, the easier it is for the major axes of the liquid crystal molecules or their mesogens to be aligned in each of the liquid crystal portions 142 to 144. The angle formed by these grooves is, for example, 5 ° or less, and typically 3 ° or less.

  In each of the regions A2 to A4, these grooves may be arranged vertically and horizontally. The lengths of the grooves may be equal to each other or different from each other. Further, the distance between adjacent grooves in the length direction may be uniform or non-uniform. Furthermore, the distance between adjacent grooves in the width direction may be uniform or non-uniform. For example, as shown in FIG. 8, in each of the regions A2 to A4, grooves having the same length may be arranged vertically and horizontally. Or you may arrange | position the groove | channel of various length at random as shown in FIG.

  The alignment layer 22 can be formed by, for example, a method of recording a hologram pattern on a photosensitive resin material using a two-beam interference method, or a method of drawing a pattern with an electron beam. Alternatively, it can be formed by pressing a mold provided with a plurality of linear protrusions against the resin, as is done in the manufacture of surface relief holograms. For example, the alignment layer 22 is formed by a method in which an original plate provided with a plurality of linear protrusions is pressed against a thermoplastic resin layer formed on the substrate 21 while applying heat, that is, by a hot embossing method. can get. Alternatively, the alignment layer 22 is formed by applying an ultraviolet curable resin on the base material 21, irradiating the ultraviolet light from the base material 21 side while pressing the original plate on the substrate 21 to cure the ultraviolet curable resin, and then removing the original plate. It is also possible to form.

  According to these methods, a plurality of regions having different groove length directions can be formed in one plane. Further, according to these methods, a plurality of regions having different groove depths, widths, and / or grooves can be formed in one plane.

  The original plate can be obtained, for example, by performing electroforming of a mother die obtained by a method of recording a hologram pattern using a two-beam interference method, a method of drawing a pattern by an electron beam, or a method of cutting by a cutting tool. It is done. If the alignment layer 22 does not have such a variety as described above, grooves may be formed by rubbing.

  The depth of these grooves is, for example, in the range of 0.05 μm to 1 μm. The length of the groove is, for example, 0.5 μm or more. The pitch of the grooves is, for example, 0.1 μm or more, and typically 0.75 μm or more. The pitch of the grooves is, for example, 10 μm or less, and typically 2 μm or less. In order to align liquid crystal molecules or their mesogens with a high degree of order, it is advantageous that the groove pitch is small.

  On the alignment layer 22 formed by the method described above, the liquid crystal layer 14 is formed. The liquid crystal layer 14 is formed by solidifying a liquid crystal material.

  For example, a photopolymerizable nematic liquid crystal material having fluidity is applied on the alignment layer 22. When a liquid crystal material is applied to the alignment layer 22, mesogens of the liquid crystal material are arranged along the length direction of the groove. If necessary, the orientation of the mesogen is promoted by heating. Next, the liquid crystal material is solidified while maintaining the alignment state of the mesogen. For example, the liquid crystal material is irradiated with ultraviolet rays to cause polymerization thereof.

  When the liquid crystal material is solidified with the mesogen alignment state substantially maintained, liquid crystal portions 142 to 144 having different slow axis directions are obtained. In this example, the liquid crystal portion 142 in which the mesogen is aligned in the X direction, the liquid crystal portion 143 in which the mesogen is aligned in the Y direction, and the mesogen when viewed from the substrate 21 side in the clockwise direction with respect to the X direction. Thus, a liquid crystal portion 144 aligned in a direction forming an angle of 45 ° is obtained.

Refractive index for alignment direction of the mesogens is extraordinary refractive index n _e, the refractive index in the direction orthogonal to the orientation direction is the ordinary index n _o. Then, the refractive index n _e is greater than the refractive index n _o. Therefore, the slow axis of the liquid crystal portion 142 is parallel to the X direction, and the fast axis is parallel to the Y direction. Further, the slow axis of the liquid crystal portion 143 is parallel to the Y direction, and the fast axis is parallel to the X direction. When the intermediate product 20 is viewed from the base material 21 side, the slow axis of the liquid crystal portion 144 is 45 ° clockwise with respect to the X direction, and the fast axis is with respect to the X direction. The angle is 45 ° counterclockwise.

  Further, on the surface of the liquid crystal layer 14 obtained by such a method facing the alignment layer 22, a plurality of linear protrusions are provided corresponding to the plurality of grooves provided on the surface of the alignment layer 22. Yes. When the structure shown in FIGS. 6 to 8 is adopted for the alignment layer 22, the diffraction grating is formed by linear protrusions or grooves provided on the surface of the liquid crystal layer 14 by making the grooves substantially parallel and setting the pitch appropriately. Can be configured. When the structure shown in FIG. 9 is employed, a unidirectional diffusion pattern can be formed by linear protrusions or grooves provided on the surface of the liquid crystal layer 14. In this unidirectional diffusion pattern, the diffusivity in the plane perpendicular to the length direction of the linear protrusions or grooves is perpendicular to the main surface of the liquid crystal layer 14 and the length of the linear protrusions or grooves. It is a pattern showing a larger light diffusion characteristic, that is, light scattering anisotropy, compared with the diffusivity in a plane parallel to the vertical direction. Here, as an example, it is assumed that the linear protrusions or grooves provided in each of the liquid crystal portions 142 to 144 constitute a diffraction grating.

  As described above, the liquid crystal layer 23 in which the orientation of the major axis of liquid crystal molecules or mesogens is fixed is obtained. Here, a nematic liquid crystal material is used as the material of the liquid crystal layer 23, but a cholesteric liquid crystal material or a smectic liquid crystal material may be used. Further, the material of the liquid crystal layer 23 may be thermally polymerizable. In this case, the liquid crystal material may be cured by heating.

  Next, the optical element 10 shown in FIGS. 1 to 3 is manufactured using the liquid crystal layer 14 of the intermediate product 20. That is, the base material 11 and the liquid crystal layer 14 are bonded together with the reflective layer 12 and the intermediate layer 13 interposed therebetween. The alignment layer 22 and the substrate 11 are removed from the liquid crystal layer 14 at an appropriate stage. Thereafter, the anchor layer 15 and the colored pattern layer 16 are sequentially formed on the liquid crystal layer 14 to obtain the optical element 10 shown in FIGS.

  Next, an image that is seen when the optical element 10 is irradiated with white light and observed with the naked eye will be described. White light is light composed of non-polarized light having all wavelengths in the visible region. Further, in FIGS. 1 to 3 and other drawings, reference numerals 101 to 104 denote display units obtained by dividing the optical element 10 along a boundary parallel to the Z direction. Specifically, the portion corresponding to the colored pattern layer 16 in the optical element 10 is the display unit 101, and the portion corresponding to the liquid crystal portion 142 among the remaining portions of the optical element 10 is the display unit 102. A portion corresponding to the portion 143 is the display unit 103, and a portion corresponding to the liquid crystal portion 144 is the display unit 104.

  When the optical element 10 is irradiated with white light and observed with the naked eye, the display units 102 to 104 are impossible or difficult to distinguish from each other as shown in FIG. To 104 is easy to distinguish. Therefore, an image corresponding to the colored pattern 16 can be observed. This will be described in more detail.

  White light as illumination light incident on the display unit 102 passes through the anchor layer 15 and the liquid crystal portion 142 shown in FIG. 2 in this order. Since a diffraction grating is formed on the front surface of the liquid crystal portion 142, a part of this incident light passes through the intermediate layer 13 as diffracted light and is reflected by the reflective layer 12. Since the reflective layer 12 has light scattering properties, the reflected light is scattered light. This scattered light passes through the intermediate layer 13, the liquid crystal portion 142, and the anchor layer 15 in this order. A diffraction grating is formed on the front surface of the liquid crystal portion 142. In addition to the reflected light from the reflective layer 12 being scattered light, the incident angle of illumination light varies in a normal environment. Therefore, the observer perceives this scattered light as a display color. Therefore, the display unit 102 looks silvery white.

  The display units 102 to 104 have different mesogen orientation directions, but the observer cannot perceive the difference. The display units 102 to 104 are different in the length direction of the grooves of the diffraction grating. As is apparent from the above description, when the display unit 102 is observed with the naked eye, the diffraction grating has a display color and brightness. Does not affect. Accordingly, the display units 103 and 104 also appear silver white.

  The display unit 101 is different from the display unit 104 in that it includes the colored pattern layer 16. Therefore, the display unit 104 looks like a color derived from the colored pattern layer 16. That is, when the colored pattern layer 16 is light transmissive, the display unit 104 looks a color corresponding to the light transmitted by the colored pattern layer 16 when illuminated with white light. And when the colored pattern layer 16 is light-shielding, the display part 104 looks the color corresponding to the light which the colored pattern layer 16 reflects, when illuminated with white light.

  In this way, the display units 102 to 104 appear silver-white, and the display unit 101 appears to be a color derived from the colored pattern layer 16. The display units 102 to 104 have substantially the same brightness. Accordingly, when the optical element 10 is irradiated with white light and observed with the naked eye from the front, the display units 102 to 104 cannot be distinguished from each other as shown in FIG. Is easily discriminated from the display units 102 to 104.

  Next, an image that is seen when the optical element 10 is observed through a polarizer will be described. Here, as an example, a linearly polarizing film is used as the polarizer.

  FIG. 10 is a plan view schematically showing an example of an image that can be observed when the optical element shown in FIGS. 1 to 3 and the linearly polarizing film are overlapped.

  In FIG. 10, when the optical element 10 shown in FIGS. 1 to 3 and the absorption linear polarizing film 50 are viewed from the polarizing film 50 side, the transmission axis of the polarizing film 50 is in the X direction. Are stacked in a clockwise direction at an angle of 45 °. When such an arrangement is adopted and this is observed from the front, as shown in FIG. 10, the display units 101 to 103 can be easily distinguished from the display unit 104, and the display units 102 and 103 are separated from the display unit 101. Discrimination is easy and discrimination from each other is impossible or difficult. This will be described in more detail.

  When the polarizing film 50 is irradiated with white light as illumination light, the linear polarizing film 50 transmits linearly polarized light having a polarization plane parallel to its transmission axis (vibration plane of the electric field vector), and a polarization plane perpendicular to the transmission axis. Absorbs linearly polarized light having

The linearly polarized light incident on the display unit 102 passes through the anchor layer 15 and the liquid crystal portion 142 shown in FIG. 2 in this order. In the liquid crystal portion 142, mesogens are aligned substantially parallel to the X direction. That is, when viewed from the polarizing film 50 side, the slow axis of the liquid crystal portion 142 is parallel to the direction rotated 45 ° counterclockwise with respect to the transmission axis of the polarizing film 50. Thus, for example, the light component having a certain wavelength λ _{0 in} the previous linearly polarized light is converted to right circularly polarized light by transmitting through the liquid crystal portion 142, and the remaining light component is transmitted through the liquid crystal portion 142. Is converted into right elliptically polarized light.

  These right circularly polarized light and right elliptically polarized light are transmitted through the intermediate layer 13 and are incident on the reflective layer 12. Since a diffraction grating is formed on the front surface of the liquid crystal portion 142, a part of this incident light is incident on the reflective layer 12 as diffracted light.

  Right circularly polarized light and right elliptically polarized light as diffracted light incident on the reflective layer 12 are reflected by the reflective layer 12. The right circularly polarized light and the right elliptically polarized light are respectively converted into left circularly polarized light and left elliptically polarized light by being reflected by the reflective layer 12. Moreover, since the reflective layer 12 has light scattering properties, this reflected light is scattered light.

  The left circularly polarized light and the left elliptically polarized light as the scattered light pass through the intermediate layer 13 and enter the liquid crystal portion 142. A diffraction grating is formed on the front surface of the liquid crystal portion 142. In addition to the reflected light from the reflective layer 12 being scattered light, the incident angle of illumination light varies in a normal environment. Therefore, the reflected light from the reflective layer 12 passes through the liquid crystal portion 142 and the anchor layer 15 in this order as scattered light.

Further, since this incident light is scattered light, it includes a light component traveling in the front direction and a light component traveling in the oblique direction. Among the light components traveling in the front direction, the left circularly polarized light having the specific wavelength λ ₀ is converted into linearly polarized light whose polarization plane is perpendicular to the transmission axis of the polarizing film 50 by transmitting through the liquid crystal portion 142. . The remaining light component passes through the liquid crystal portion 142 and is converted into left elliptical polarization, left circular polarization, right elliptical polarization, or right circular polarization.

  That is, when focusing only on the light component having a polarization plane parallel to the transmission axis of the polarizing film 50, the ratio of the intensity of the light component emitted by the display unit 102 to the intensity of the light component incident on the display unit 102 is It has wavelength dependency. In other words, the ratio of the intensity of the display light emitted from the polarizing film 50 to the intensity of the illumination light incident on the polarizing film 50 has wavelength dependency. Accordingly, the display unit 102 appears colored. The reason why the display unit 102 appears colored will be described later with reference to mathematical expressions.

  The display unit 103 and the display unit 102 are different only in that the length directions of the grooves constituting the diffraction grating are different by 90 ° and the orientation directions of mesogens are different by 90 °. Therefore, the display unit 103 behaves in the same manner as described for the display unit 102 except that the rotation direction of the polarization plane of circularly polarized light or elliptically polarized light is reversed. Therefore, the display unit 103 looks colored similarly to the display unit 102.

  The display unit 104 and the display unit 102 are different only in that the length directions of the grooves constituting the diffraction grating are different by 45 ° and the orientation directions of mesogens are different by 45 °. That is, in the display unit 104, the orientation direction of the mesogen is parallel to the transmission axis of the polarizing film 50. Therefore, the birefringence of the liquid crystal portion 144 does not affect the display. Therefore, unlike the display units 102 and 103, the display unit 104 looks silver-white without being colored.

  The display unit 101 is different from the display unit 104 in that it includes the colored pattern layer 16. Therefore, the display unit 104 looks like a color derived from the colored pattern layer 16.

  Thus, the display units 102 and 103 appear colored, the display unit 104 looks silvery white, and the display unit 101 looks like a color derived from the colored pattern layer 16. The display units 102 and 103 have substantially the same brightness. Therefore, when the polarizing film 50 is overlaid on the optical element 10 and irradiated with white light and observed from the front, the display units 101 to 103 are easily discriminated from the display unit 104 as shown in FIG. The display units 102 and 103 are easily discriminated from the display unit 101 and cannot be discriminated from each other.

  At this time, it is theoretically impossible to distinguish the display units 102 and 103 from each other. However, due to the accuracy of the grooves provided in the polarizing film 50 and the alignment layer 22, the display light spectrum may differ between the display units 102 and 103, and as a result, they may be discriminated from each other. .

Here, the reason why the display unit 102 appears to be colored will be described with reference to mathematical expressions. Note that the liquid crystal portion 142 serves as a quarter-wave plate for light having a wavelength λ ₀ .

It can be considered that the linearly polarized light having the wavelength λ ₀ emitted from the polarizing film 50 in the normal direction is the sum of the linearly polarized light component whose polarization plane is perpendicular to the X direction and the linearly polarized light component whose polarization plane is perpendicular to the Y direction. it can. As described above, the refractive index in the X direction of the liquid crystal part 142 is extraordinary refractive index n _e, the refractive index in the Y direction is the ordinary index n _o. Therefore, the liquid crystal part 142, these linear polarization component, providing a phase difference of lambda _0/4 in forward and return each. That is, the liquid crystal part 142 gives a phase difference of lambda _0/2 in total of these linearly polarized light components. Therefore, the light with the wavelength λ ₀ emitted from the display unit 102 in the normal direction cannot pass through the polarizing film 50.

By the way, the retardation Re depends on the film thickness d of the liquid crystal layer and its birefringence Δn as shown in the following equation (1).
Re = Δn × d (1)
Here, a Δn = n _e -n _o.

A pair of linearly polarizing films face each other so that their transmission axes are orthogonal to each other, and a liquid crystal layer is interposed between them so that the optical axis forms an angle of 45 ° with respect to the transmission axis of the linearly polarizing film. When one linearly polarizing film is illuminated with light having a wavelength λ from its normal direction, the intensity of light incident on the liquid crystal layer is I ₀ and the intensity of light passing through the other linearly polarizing film is I. I can be represented by the following equation (2).
I = I ₀ × sin ² (Re × π / λ) (2)
The birefringence Δn has wavelength dependency, and the birefringence Δn and the wavelength n are not in a proportional relationship. Therefore, as is clear from equation (2), the spectrum of transmitted light has a different profile from the spectrum of incident light.

  Thus, when the liquid crystal layer is sandwiched between a pair of linearly polarizing films, transmitted light having a spectrum profile different from that of incident light can be obtained. Similarly, when the liquid crystal layer is sandwiched between the linearly polarizing film and the reflective layer, reflected light having a spectrum profile different from that of the incident light can be obtained. For this reason, the display unit 102 appears colored.

FIG. 11 is a perspective view showing another example of an image displayed by the optical element shown in FIGS.
As shown in FIG. 11, when the observation direction is tilted in a plane perpendicular to the X direction in the state shown in FIG. 10, the display colors of the display units 102 and 103 change to different colors. As a result, the display units 102 and 103 can be easily distinguished from each other. For example, if the display units 102 and 103 look purple when viewed from the normal direction, the color of the display unit 102 changes to red by tilting the observation direction in a plane perpendicular to the X direction. The display unit 103 changes to green. The reason for the color change that occurs in the display units 102 and 103 will be described below.

When the observation angle θ is tilted, the effective birefringence Δn ′ of the liquid crystal layer changes from the birefringence Δn, and the effective film thickness d ′ of the liquid crystal layer shown in the following equation (3) is It is larger than twice the actual film thickness d.
d ′ = 2d / cos θ (3)
That is, the retardation Re shown in the above equation (1) changes according to the observation angle, and therefore the intensity I shown in the above equation (2) changes. As a result, the spectrum profile of the display light changes according to the observation angle.

  The birefringence Δn ′ depends on the incident angle of the illumination light and the angle formed by the projection onto the principal surface of the liquid crystal layer parallel to the propagation direction of the illumination light with respect to the optical axis of the liquid crystal layer. Specifically, the birefringence Δn ′ of the liquid crystal portion 142 does not change even when the observation direction is tilted in a plane perpendicular to the X direction because its optical axis is parallel to the X direction. On the other hand, the birefringence Δn ′ of the liquid crystal portion 143 changes as the observation direction is tilted in a plane perpendicular to the X direction because its optical axis is parallel to the Y direction.

  As described above, the display unit 102 causes a color change due to an effective change in the film thickness d ′ when the observation direction is tilted in a plane perpendicular to the X direction. On the other hand, when the viewing direction is tilted in a plane perpendicular to the X direction, the display unit 103 changes color due to an effective change in the film thickness d ′ and an effective change in the birefringence Δn ′. Arise. Therefore, when the observation direction is tilted in a plane perpendicular to the X direction, the display colors of the display units 102 and 103 change to different colors, and as a result, the display units 102 and 103 can be distinguished from each other. Become.

  FIG. 12 is a perspective view showing still another example of an image displayed by the optical element shown in FIGS. 1 to 3.

  FIG. 12 shows an image that can be observed when the optical element 10 and the polarizing film 50 are rotated 90 ° around the normal in the state shown in FIG. When the optical element 10 is rotated 90 ° around the normal line together with the polarizing film 50 while the observation direction is oblique, the display color is switched between the display unit 102 and the display unit 103. The color change described with reference to FIG. 12 also occurs when only the optical element 10 is rotated by 90 ° around the normal in the state shown in FIG.

  As described above, the image displayed by the optical element 10 shown in FIGS. 1 to 3 changes variously according to the observation conditions, as exemplified below.

  The display units 102 and 103 display the same color when viewed from the normal direction without the polarizing film 50.

  The display units 102 and 103 display the same color when observed from the normal direction without the polarizing film 50 and when observed from the oblique direction without the polarizing film 50.

  The display units 102 and 103 display substantially equal colors when observed from the normal direction through the polarizing film 50.

  The display units 102 and 103 display different colors when observed from an oblique direction through the polarizing film 50.

  The display units 102 and 103 display different colors when observed from the normal direction through the polarizing film 50 and when viewed from an oblique direction through the polarizing film.

  The display units 102 and 103 cause a color change when the position and orientation of the polarizing film 50 are fixed and the optical element 10 is observed from an oblique direction through the polarizing film 50 while rotating around the normal line.

  The display units 102 and 103 cause a color change when the position and orientation of the optical element 10 are fixed and the polarizing film 50 is observed from an oblique direction while rotating the polarizing film 50 around the normal line.

  The display units 102 and 103 fix the position and orientation of the polarizing film 50, and the display color changes when the optical element 10 is observed from an oblique direction through the polarizing film 50 while rotating around the normal line. Change.

  In the case where the display units 102 and 103 fix the relative arrangement of the optical element 10 and the polarizing film 50 and observe them from an oblique direction through the polarizing film 50 while rotating them around the normal line. The display color changes.

  The display unit 104 displays the same color as the display units 102 and 103 when observed from the normal direction without the polarizing film 50.

  The display unit 104 displays the same color when observed from the normal direction without the polarizing film 50 and when observed from the oblique direction without the polarizing film 50.

  -The display part 104 does not produce a color change, when observing from the diagonal direction, rotating the optical element 10 around the normal line without the polarizing film 50. FIG.

  -The display part 104 produces a color change, when it observes from the diagonal direction through this, rotating the polarizing film 50 around the normal line.

  The color and brightness of the display unit 101 do not change according to the observation angle both when the display unit 101 is observed without the polarizing film 50 and when the display unit 101 is observed through the polarizing film 50.

  -The display part 101 does not produce a color change, when it observes from the diagonal direction through this, rotating the polarizing film 50 around the normal line.

  As described above, the image displayed by the optical element 10 shown in FIGS. 1 to 3 varies depending on the observation conditions. And since this optical element 10 is provided with the colored pattern layer 16, even when it observes without the polarizing film 50, it displays an image. Therefore, the optical element 10 provides an excellent anti-counterfeit effect, a decorative effect, and / or an aesthetic effect.

  For example, when a labeled article including the optical element 10 and an article that supports the optical element 10 is an authentic product, if an article whose authenticity is unknown does not exhibit one or more of the above-described features, It can be determined that the article is non-genuine. That is, it is possible to discriminate an article whose authenticity is unknown between a genuine product and a non-authentic product. Therefore, for example, forgery of securities, banknotes, identification cards and other high-quality items such as printed matter such as credit cards and fine arts can be prevented or suppressed. Further, the optical kit including the optical element 10 and the polarizing film 50 can be used as a toy, a learning material, or an ornament in addition to being usable for the previous authenticity determination.

  As will be described later, the optical element 10 has one combination of the display unit 104 and a part of the display units 102 to 103 when observed through the polarizing film 50 or the naked eye. You may employ | adopt the structure which displays an image, for example, a character, a character string, a symbol, a figure, or those combination. In this way, a more complicated visual effect can be achieved, and a better anti-counterfeit effect, a decorative effect and / or an aesthetic effect can be realized.

  Further, when an optically variable ink is used for the colored pattern layer 16, not only the display units 102 and 103 but also the display unit 101 causes a color change corresponding to the observation angle when observed from an oblique direction through a polarizing film. be able to. Therefore, in this case as well, a more complicated visual effect can be achieved, and a better anti-counterfeit effect, a decorative effect, and / or an aesthetic effect can be realized.

Next, the second aspect of the present invention will be described.
FIG. 13 is a plan view schematically showing an optical element according to the second aspect of the present invention. 14 is a cross-sectional view of the optical element shown in FIG. 13 taken along line XIV-XIV.

  The optical element 10 has the same configuration as the optical element 10 described with reference to FIGS. 1 to 3 except that the following configuration is adopted. That is, in the optical element 10, the liquid crystal layer 14 includes a liquid crystal portion 145 instead of the liquid crystal portion 142. The liquid crystal portion 145 is thicker than the portion 142. In addition, the front surface of the liquid crystal portion 145 is provided with a groove similar to that provided on the front surface of the liquid crystal portion 143, that is, a plurality of grooves whose length direction is parallel to the Y direction and arranged in the X direction. ing. In the liquid crystal portion 145, the mesogen is aligned in the Y direction. In FIGS. 13 and 14, the portion denoted by reference numeral 105 is a portion corresponding to the liquid crystal portion 145 in the optical element 10.

  The optical element 10 displays an image similar to that described with reference to FIG. 1 when observed with the naked eye. However, the optical element 10 displays an image different from the optical element 10 described with reference to FIGS. 1 to 3 when observed through a polarizer.

  FIG. 15 is a plan view schematically showing an example of an image that can be observed when the optical element shown in FIGS. 13 and 14 and the linearly polarizing film are overlaid. FIG. 16 is a perspective view illustrating another example of an image displayed by the optical element illustrated in FIGS. 13 and 14. FIG. 17 is a perspective view showing still another example of an image displayed by the optical element shown in FIGS. 13 and 14.

  15 to 17, when the optical element 10 shown in FIGS. 13 and 14 and the absorption linear polarizing film 50 are viewed from the polarizing film 50 side, the transmission axis of the polarizing film 50 is X. They are stacked so as to make an angle of 45 ° clockwise with respect to the direction. When such an arrangement is adopted and this is observed from the front, as shown in FIG. 15, the display units 101 and 103 to 105 can be easily distinguished from each other. This will be described in more detail. Since the display units 101 and 104 appear to have the same color as that observed under the conditions described with reference to FIG. 10, the description thereof is omitted here.

  As is clear from the explanation using the equations (1) and (2), the colors displayed on the display units 103 and 105 when the optical element 10 and the polarizing film 50 are overlapped and these are observed from the front are liquid crystals. Depends on the thickness d of the portions 143 and 145. Since the liquid crystal portion 143 and the liquid crystal portion 145 have different thicknesses, the display units 103 and 105 display different colors. For example, the display unit 103 looks green and the display unit 105 looks yellow. Thus, when the polarizing film 50 is overlapped on the optical element 10 and observed from the front, the display units 103 and 105 display different colors.

  Further, as shown in FIG. 16, when the observation direction is tilted in a plane perpendicular to the X direction in the state shown in FIG. The color change caused by That is, the display unit 105 causes a color change different from that of the display unit 102 of the optical element 10 shown in FIGS.

  Then, as shown in FIG. 17, when the optical element 10 and the polarizing film 50 are rotated 90 ° around the normal line in the state shown in FIG. 16, the display unit 105 is similar to the display unit 103. Then, a color change caused by an effective change in film thickness d ′ and an effective change in birefringence Δn ′ occurs. However, the actual film thickness d differs between the display unit 105 and the display unit 103. Accordingly, the display unit 105 causes a color change different from that of the display unit 102 of the optical element 10 shown in FIGS.

  That is, this optical element 10 does not have the following features, unlike the optical element 10 described with reference to FIGS.

  The display units 105 and 103 display substantially the same color when viewed from the normal direction through the polarizing film 50.

  The display units 105 and 103 fix the position and orientation of the polarizing film 50, and the display color changes when the optical element 10 is observed from an oblique direction through the polarizing film 50 while rotating around the normal line. Change.

  When the display units 105 and 103 are observed from an oblique direction through the polarizing film 50 while fixing the relative arrangement of the optical element 10 and the polarizing film 50 and rotating them around the normal line. The display color changes.

  Instead, the optical element 10 has the following characteristics.

  The display units 105 and 103 display different colors when observed from the normal direction through the polarizing film 50.

  The display units 105 and 103 are different from each other when the position and orientation of the polarizing film 50 are fixed and the optical element 10 is rotated around the normal line and observed from an oblique direction through the polarizing film 50. A color change occurs while displaying.

  When the display units 105 and 103 fix the relative position of the optical element 10 and the polarizing film 50 and rotate the polarizing film 50 around its normal line and observe it from an oblique direction through this, The color change occurs while displaying different colors.

  Accordingly, this optical element 10 also provides, for example, an excellent anti-counterfeiting effect, a decoration effect, and / or an aesthetic effect, like the optical element 10 described with reference to FIGS. Therefore, when a labeled article including the optical element 10 and a printed material supporting the optical element 10 is an authentic product, when an article whose authenticity is unknown does not exhibit one or more of the above-described features, It can be determined that the article is non-genuine. That is, it is possible to discriminate an article whose authenticity is unknown between a genuine product and a non-authentic product. Further, the optical kit including the optical element 10 and the polarizing film 50 can be used as a toy, a learning material, an ornament, and the like in addition to being usable for the previous authenticity determination.

  When the thicknesses of the liquid crystal portion 143 and the liquid crystal portion 145 are different, the difference in thickness is, for example, in the range of 0.1 μm to 5 μm. When this difference is small, it is difficult to distinguish the display unit 105 and the display unit 103 from each other when observed through the polarizing film 50. If this difference is large, it becomes difficult to orient mesogens with a high degree of order in the thicker liquid crystal portion. As a result, it becomes difficult to display the designed color when observed through the polarizing film 50.

Next, the third aspect of the present invention will be described.
FIG. 18 is a plan view schematically showing an optical element according to the third aspect of the present invention.

  The optical element 10 has the same configuration as the optical element 10 described with reference to FIGS. 1 to 3 except that the following configuration is adopted. That is, in the optical element 10, the display unit 103 is omitted. The optical element 10 is designed so that the display units 101 and 102 display the same color when observed under specific conditions using a polarizer. For example, by optimizing the transmission spectrum and reflection spectrum of the colored pattern layer 16, the orientation direction of the mesogen in the liquid crystal portion 142, the film thickness of the liquid crystal portion 142, and the reflectance and light scattering ability of the reflective layer 12, the polarizer is optimized. The display units 101 and 102 display the same color when observing under specific conditions using the.

  The optical element 10 displays an image corresponding to the display unit 101 when observed with the naked eye. And when it observes on the specific conditions which use a polarizer, the image corresponding to the combination of the display part 101 and the display part 102 is displayed so that it may demonstrate below.

  FIG. 19 is a plan view schematically showing an example of an image that can be observed when the optical element shown in FIG. 18 and a linearly polarizing film are overlaid.

  In FIG. 19, when the optical element 10 and the absorption linear polarizing film 50 shown in FIG. 18 are viewed from the polarizing film 50 side, the transmission axis of the polarizing film 50 is clockwise with respect to the X direction. Are overlapped at an angle of 45 °. When such an arrangement is adopted and observed from the front, the display unit 102 appears colored. If the colors of the display unit 101 and the display unit 102 are the same, as shown in FIG. 19, it is difficult to distinguish the display unit 101 and the display unit 102 from each other. In other words, it becomes easy to view the display unit 101 and the display unit 102 as one display unit.

  Accordingly, when observed with the naked eye, the letter “P” is displayed as shown in FIG. 18, and the letter “B” as shown in FIG. 19 is displayed only when observed under a specific condition using a polarizer. "Can be displayed. That is, one piece of information can be displayed by the visible image formed by the display unit 101 and the latent image formed by the display unit 102.

  This information cannot be read when the optical element 10 is observed with the naked eye. And even if it is a case where the polarizing film 50 is used, unless it observes on specific conditions, the display part 101 and the display part 102 do not look the same color. Therefore, this information is difficult to read illegally.

  Various modifications can be made to the optical element 10 described above.

  For example, as the reflective layer 12, a layer having a metal reflective surface provided with a fine uneven structure may be used. For example, a fine uneven structure is provided on the front surface of the substrate 11. In this case, the base material 11 may or may not have optical transparency. Then, a layer made of a metal or an alloy is formed on the front surface of the substrate 11 by, for example, a vapor deposition method such as a vacuum evaporation method or a sputtering method. As the metal or alloy, for example, aluminum, silver, nickel, chromium, or an alloy thereof can be used. The reflective layer 12 is obtained as described above. The reflective layer 12 thus obtained has light scattering properties because it includes a concavo-convex structure derived from a fine concavo-convex structure provided on the front surface of the substrate 11 on the front surface.

  The reflective layer 12 may be a single-layer or multilayer dielectric film having a fine uneven structure on the front surface. For example, when a single-layer dielectric film made of zinc sulfide is used as the reflective layer 12, the background color of the reflective layer 12 can be perceived when the optical element 10 is observed with the naked eye. Further, when the optical element 10 is observed through a polarizer, the visual effect given by the background color of the reflective layer 12 can be added to the visual effect given by the liquid crystal layer 12. When a multilayer dielectric film is used as the reflective layer 12, the optical element 10 can be given wavelength selectivity. Accordingly, it is possible to obtain a visual effect different from the case where a metal vapor deposition layer or a single-layer dielectric film is used as the reflective layer 12. The multilayer dielectric film is obtained by alternately depositing a high refractive index material such as zinc sulfide and a low refractive index material such as magnesium fluoride on the substrate 11.

The optical element 10 may further include a protective layer and an adhesive layer described below.
FIG. 20 is a cross-sectional view showing a modification of the optical element shown in FIGS.

  The optical element 10 shown in FIG. 20 has the same structure as the optical element 10 described with reference to FIGS. 1 to 3 except that the optical element 10 further includes a protective layer 17 that covers the colored pattern layer 16. Yes. When the protective layer 17 is provided, the liquid crystal layer 15 or the like can be hardly damaged or light deteriorated, and deterioration of an image displayed by the optical element 10 can be suppressed. In addition, peeling of the colored pattern layer 16 can be prevented.

  As a material of the protective layer 17, for example, a hard coat material having excellent scratch resistance can be used. Alternatively, as the material of the protective layer 17, for example, acrylic resin, urethane resin, vinyl chloride resin-vinyl acetate copolymer resin, polyester resin, melamine resin, epoxy resin, polystyrene resin, polyimide resin, and other thermoplastic resins, thermosetting , Or ultraviolet or electron beam curable resins can be used alone or in combination. In order to impart friction resistance and the like to these resins, waxes such as polyethylene washes, carnauba wax and silicone wax, extender pigments such as calcium carbonate, zinc stearate, silica, alumina and talc, or silicone oils and the like These fats and oils can be added within a range that does not impair the transparency of the resin. The protective layer 17 may be colorless and transparent, or may be colored and transparent.

FIG. 21 is a cross-sectional view showing another modification of the optical element shown in FIGS.
The optical element 10 shown in FIG. 21 has the same structure as the optical element 10 described with reference to FIG. 20 except that the optical element 10 further includes an adhesive layer 18 that covers the back surface of the substrate 11. This optical element 10 is suitable for an application to be used by being attached to an article. The adhesive layer 18 may be covered with release paper.

Instead of using the polarizing film 50 as the polarizer, other types of polarizers such as a plate-like polarizer may be used. Moreover, you may use a circular polarizer or an elliptical polarizer instead of a linear polarizer. In this case, it is possible to observe a color change different from the case where a linear polarizer is used. Therefore, a more complicated visual effect can be obtained.
The invention described in the original claims is appended below.
[1]
A light-scattering reflective layer, a liquid crystal layer made of a solidified liquid crystal material facing at least part of one main surface of the reflective layer, and a part of the liquid crystal layer sandwiched therebetween or between the liquid crystal layers A colored pattern layer facing a part of the main surface without being sandwiched between,
The liquid crystal layer includes a plurality of liquid crystal portions that are adjacent to each other in an in-plane direction and have different orientation directions or film thicknesses of mesogens.
The first display unit corresponding to the colored pattern layer, and when viewed with the naked eye, the first display unit looks different from the first display unit and is observed from a specific observation direction through a polarizer. And a second display portion that looks the same color as the optical element.
[2]
The optical element according to [1], wherein the liquid crystal layer includes the plurality of liquid crystal portions that are adjacent to each other in an in-plane direction and have different mesogen alignment directions.
[3]
The optical element according to [1] or [2], wherein the liquid crystal layer includes the plurality of liquid crystal portions adjacent to each other in an in-plane direction and having different film thicknesses.
[4]
Any one of [1] to [3], further including a third display unit that looks different from the first display unit when viewed from the observation direction through a polarizer. The optical element described.
[5]
The optical element according to any one of [1] to [4], wherein the observation direction is perpendicular to a display surface of the optical element.
[6]
The optical element according to any one of [1] to [4], wherein the observation direction is oblique with respect to a display surface of the optical element.
[7]
At least one surface of the plurality of liquid crystal portions is provided with a plurality of grooves that are aligned in the length direction and are adjacent to each other in a direction intersecting the length direction [1] to [6] ] The optical element of any one of.
[8]
The optical element according to any one of [1] to [7], wherein the reflective layer includes a metal reflective layer.
[9]
[1] An article with a label comprising the optical element according to any one of [8] and an article supporting the optical element.
[10]
An optical kit comprising the optical element according to any one of [1] to [8] and a polarizer.

1 is a plan view schematically showing an optical element according to a first embodiment of the present invention. Sectional drawing along the II-II line | wire of the optical element shown in FIG. Sectional drawing along the III-III line of the optical element shown in FIG. The top view which shows roughly the intermediate product obtained in an example of the manufacturing process of the optical element shown in FIG. 1 thru | or FIG. Sectional drawing along the VV line of the intermediate product shown in FIG. The top view which shows roughly an example of the structure employable on the surface of an alignment layer. The top view which shows schematically the other example of the structure employable on the surface of an orientation layer. The top view which shows schematically the further another example of the structure employable on the surface of an orientation layer. The top view which shows schematically the further another example of the structure employable on the surface of an orientation layer. The top view which shows roughly an example of the image which can be observed when the optical element shown in FIG. 1 thru | or FIG. FIG. 4 is a perspective view showing another example of an image displayed by the optical element shown in FIGS. 1 to 3. FIG. 4 is a perspective view showing still another example of an image displayed by the optical element shown in FIGS. 1 to 3. The top view which shows roughly the optical element which concerns on the 2nd aspect of this invention. Sectional drawing along the XIV-XIV line of the optical element shown in FIG. The top view which shows roughly an example of the image which can be observed when the optical element shown in FIG.13 and FIG.14 and a linearly polarizing film are piled up. The perspective view which shows the other example of the image which the optical element shown in FIG.13 and FIG.14 displays. FIG. 15 is a perspective view showing still another example of an image displayed by the optical element shown in FIGS. 13 and 14. The top view which shows roughly the optical element which concerns on the 3rd aspect of this invention. The top view which shows roughly an example of the image which can be observed when the optical element shown in FIG. 18 and a linearly polarizing film are piled up. Sectional drawing which shows the modification of the optical element shown to FIG. Sectional drawing which shows the other modification of the optical element shown to FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Optical element, 11 ... Base material, 12 ... Reflective layer, 13 ... Intermediate layer, 14 ... Liquid crystal layer, 15 ... Anchor layer, 16 ... Colored pattern layer, 17 ... Protective layer, 18 ... Adhesive layer, 20 ... Intermediate product , 21 ... base material, 22 ... alignment layer, 50 ... polarizing film, 142 ... liquid crystal part, 143 ... liquid crystal part, 144 ... liquid crystal part, 101 ... display part, 102 ... display part, 103 ... display part, 104 ... display part 105, a display unit, A2, a region, A3, a region, A4, a region.

Claims (10)

A light-scattering reflective layer, a liquid crystal layer made of a solidified liquid crystal material facing at least part of one main surface of the reflective layer, and a part of the liquid crystal layer sandwiched therebetween or between the liquid crystal layers A colored pattern layer facing a part of the main surface without being sandwiched between ,
The liquid crystal layer includes a plurality of liquid crystal portions that are adjacent to each other in an in-plane direction and have different orientation directions or film thicknesses of mesogens.
The first display unit corresponding to the colored pattern layer, and when viewed with the naked eye, the first display unit looks different from the first display unit and is observed from a specific observation direction through a polarizer. And a second display portion that looks the same color as the optical element. The liquid crystal layer is disposed adjacent to the in-plane direction, the optical element according to claim 1, characterized in that including a plurality liquid crystal portion of the alignment directions are different from each other of the mesogens. The liquid crystal layer is disposed adjacent to the in-plane direction, the optical element according to claim 1 or 2, characterized in that including a plurality liquid crystal portion of the film thickness are different from each other. The third display unit according to any one of claims 1 to 3, further comprising a third display unit that looks different from the first display unit when viewed from the observation direction through a polarizer. Optical element. The optical element according to any one of claims 1 to 4, characterized in that it is perpendicular to the display surface of the observation direction the optical element. The optical element according to any one of claims 1 to 4 wherein the viewing direction, characterized in that it is oblique to the display surface of the optical element. At least one surface of said plurality of liquid crystal portions of claims 1 to 6 longitudinal direction, characterized in that a plurality of grooves adjacent in a direction intersecting the aligned and the longitudinal provided The optical element according to any one of the above. The optical element according to any one of claims 1 to 7 wherein the reflecting layer is characterized by containing the metal reflective layer. Labeled article, wherein the optical element according to any one of claims 1 to 8, that contains an article supported by. An optical kit comprising the optical element according to any one of claims 1 to 8 and a polarizer.

Images