JP5629965B2 - Image forming body manufacturing method and laminate - Google Patents

Description

  The present invention can record images such as letters, numbers, patterns, biometrics (fingerprints, faces, blood vessels, etc.) information as a three-dimensional image by irradiation with laser light, or can record a plurality of images appearing at different observation angles. The present invention relates to an image forming body and an image recording method thereof.

  In the recording of an image using laser light, for example, in a diffractive structure having a reflective layer behind, information is additionally recorded by selectively irradiating laser light to destroy the reflective layer. Are known. Such a method of forming a pattern by partially removing a metal or metal oxide thin film by irradiation with laser light can additionally record a high-resolution image on demand.

  On the other hand, a method for recording a plurality of images is a method of recording a plurality of images and a three-dimensional image by printing a print pattern in consideration of the lenticular lens enlargement effect and the focal shift according to the observation angle at a lens pitch in the vicinity of the lens focal length. It is known in Patent Document 2. In particular, it is possible to obtain a three-dimensional image on demand according to a method of directly printing on a focal plane of a lenticular lens by an ink jet printing method.

Further, Patent Document 3 discloses a method of forming an image on a photosensitive film by combining a lenticular lens and a photosensitive film and performing scanning exposure from the lens side.
JP 2000-47556 A JP 2008-15048 A JP-A-8-220477

  However, the conventional technology represented by Patent Document 1 is usually a two-dimensional single image recording, and the appearance is not much different from a printed image by a melted ribbon, a sublimation transfer method, an ink jet method, or the like. It is a recording function, and it has been impossible to record an accurate image such as a three-dimensional image or a lot of information such as a two-dimensional plural image so that it can be confirmed with a glance.

  In the method disclosed in Patent Document 2, the positional accuracy and pitch accuracy of the print pattern with respect to the lens of the lenticular sheet are problematic. In particular, in order to record a high-resolution image such as a photograph, there is a problem that productivity is very low because positional accuracy in μm units is required.

  In the method disclosed in Patent Document 3, since a photosensitive film is used, it is necessary to perform complicated processing such as development, fixing, and printing, and a dedicated facility is required. Not suitable for recording.

  SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an image forming body that has good productivity without requiring a complicated process and can be recorded even on demand, and an image recording method thereof. Is to provide.

In order to solve the above-mentioned problems, the present invention has at least a lens assembly layer in which a plurality of lens-shaped portions are densely arranged on a plane, and a thin film layer positioned below the lens assembly layer, and at least An image forming body that forms an image forming layer by recording an image pattern on the thin film layer of a laminate having a focal length adjusting layer partially formed with a diffractive structure between the lens assembly layer and the thin film layer A method of manufacturing the laminate, wherein the laminated body is irradiated with laser light from a certain direction on the lens assembly layer side, and the laser light is focused on the thin film layer through the lens to partially disappear the thin film layer. An image pattern is recorded by the following.

  The present invention is also characterized in that, in the method for producing an image forming body, laser light irradiation from a predetermined direction is performed on the laminated body from a plurality of different angles.

  The present invention is also characterized in that, in the method for producing an image forming body, the thin film layer has a property of sublimating or evaporating by heating.

In addition, the present invention includes a lens assembly layer in which a plurality of lens-shaped portions are densely arranged on a plane, and a thin film layer positioned below the lens assembly layer, and at least part of the relief-type diffraction pattern A laminated body having a focal length adjusting layer formed between the lens assembly layer and the thin film layer, wherein the focal length adjusting layer has a focal point of the laser light irradiated from the lens shape portion direction. has a film thickness becomes thin layer, the thin film layer have a property of evaporating or sublimating by heating, the image forming layer for recording a plurality of image patterns to the laser beam focal position of the thin film layer is formed It is characterized by.

  Since this invention is the above structure, there exist the following effects.

  That is, the basic structure of the laminate in the present invention consists of a lens assembly and a thin film layer that has the property of evaporating or sublimating due to heat and disappears, and irradiates laser light from a certain direction on the lens assembly layer side, The thin film layer can be partially lost by the laser light collected by the individual lens shape portions. By utilizing this, laser light having an arbitrary image pattern is irradiated onto the laminate from an arbitrary direction, so that the image pattern is recorded on the thin film layer to form an image forming layer, and in the vicinity of a certain direction irradiated with the laser light. Thus, it is possible to provide an image forming body in which the image pattern can be visually recognized only from.

  Further, by recording the irradiation angle of the laser beam on the laminate from a plurality of different angles, it is possible to form an image forming layer in which a plurality of image patterns are recorded in the same space. Therefore, for example, it is possible to record a stereoscopic image in the manner of a stereogram, or to reproduce a stereoscopic image by recording parallax images of the left and right eyes, and record a more accurate image pattern than a two-dimensional image. It becomes possible to do. It is also possible to record a plurality of different two-dimensional images depending on the observation angle, and it is also possible to record more image patterns.

  In addition, since the thin film layer of the present invention is characterized in that an image pattern is formed by utilizing the property of disappearing by heat, complicated processes such as development, fixing, and baking required for general photosensitive films, It is possible to provide a laminate, an image forming body, and a method for manufacturing the same, which do not require a dedicated facility, have high productivity, and can be recorded even on demand.

  That is, according to the present invention, the thin film layer is removed by irradiating a laser beam to accurately record image patterns such as letters, numbers, pictures, biometrics (fingerprints, faces, blood vessels, etc.) information, etc. A laminated body, an image forming body, and a method for manufacturing the same, which can record an image pattern and manufacture an image forming body, have high productivity without requiring complicated processes and dedicated equipment, and can be recorded even on demand. It is possible to provide.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a laminate and an image forming body according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a cross-sectional view showing a basic structure of a laminate according to the present invention.
The laminate 1 in the present invention has a configuration including a lens assembly layer 2 in which lens shape portions are densely arranged on a plane, and a thin film layer 3 having a property of evaporating or sublimating by heating. The thin film layer 3 is disposed on the side where the light is collected when the light enters the lens assembly layer 2.

FIG. 2 is a cross-sectional view showing a first embodiment of the laminate according to the present invention.
The laminate shown in FIG. 2 has the same configuration as that of the laminate shown in FIG. 1 except that the focal length adjustment layer 4 is provided between the lens assembly layer and the thin film layer. The focal length adjustment layer serves as a spacer for adjusting the distance so that the lens focal position of the lens assembly is in the vicinity of the thin film layer.

FIG. 3 is a cross-sectional view showing a second embodiment of the laminate according to the present invention.
The laminate shown in FIG. 3 has a configuration in which the lens-shaped portion constituting the lens assembly layer of the laminate shown in FIG. 2 is a spherical lens.

FIG. 4 is a cross-sectional view showing a third embodiment of the laminate according to the present invention.
The laminate shown in FIG. 4 has a structure in which a diffractive structure is formed on at least a part of the focal length adjustment layer of the laminate shown in FIG. 2, and a thin film layer corresponding to the focal length adjustment layer on which the diffractive structure is formed is The layer is formed and laminated in a shape following the diffraction structure of the focal length adjustment layer.

  5 and 6 are diagrams for explaining a method of manufacturing an image forming body in which an image pattern is recorded on the laminate shown in FIG. Here, the laminated body shown in FIG. 2 is taken as an example, but naturally, an image pattern is similarly formed on FIGS. 3 and 4 and other laminated bodies according to the present invention. Is possible.

  As shown in FIG. 5, when the laminated body is irradiated with laser light perpendicularly, the laser light is condensed by each lens shape portion constituting the lens assembly layer, and near the thin film layer through the focal length adjustment layer. Create a focus. The thin film layer near the focal point disappears due to the heat generated by the focal point of the laser beam. As a result, an image pattern is recorded on the thin film layer to form an image forming layer, and an image forming body on which an image pattern that is visible only from the vertical direction is recorded.

  As shown in FIG. 6, when the laser beam is irradiated from the direction of an arbitrary angle α with respect to the perpendicular of the laminated body, the laser beam is condensed by each lens shape portion constituting the lens assembly layer, and the focal length adjustment layer Make a focus near the thin film layer through. The thin film layer near the focal point disappears due to the extinction of the focal point of the laser beam. As a result, the image pattern is defined on the thin film layer to become an image forming layer, and an image forming body on which an image pattern that can be visually recognized only from an arbitrary angle α with respect to the perpendicular is recorded.

  Further, an image forming body in which two image patterns are recorded using both of the methods shown in FIGS. 5 and 6 can be obtained by observing from a direction perpendicular to the image forming body as shown in FIG. The portion of the forming layer that has disappeared due to evaporation or sublimation is magnified by the lens assembly layer, and the first image pattern can be visually recognized. Then, as shown in FIG. 7B, when the image forming body is observed from the direction of an arbitrary angle α with respect to the vertical line of the image forming body, the second image pattern can be similarly recognized. The first image pattern and the second image pattern can be the same image pattern or different image patterns depending on the pattern of laser light to be irradiated.

FIG. 8 is a diagram for explaining a method of manufacturing an image forming body in which a stereoscopic image is recorded on the laminate shown in FIG.
A right-view image pattern recording portion in which the thin film layer disappears and is recorded by the laser beam 6 that irradiates the right-view image pattern, and a left-view image pattern in which the thin-film layer disappears and is recorded by the laser beam 7 that irradiates the left-view image pattern A recording portion is produced. In this case, depending on the reproduction state of the image, it is possible to obtain a three-dimensional reproduced image without distortion or missing portion even if the diffusing laser beam is used.

FIG. 9 is a diagram showing a reproduction state of a stereoscopic image when an image forming body on which a stereoscopic image is recorded by the manufacturing method shown in FIG. 8 is observed.
The right eye sees the right-view image recording portion enlarged by the lens assembly layer, and the left eye sees the left-view image recording portion enlarged by the lens assembly layer. For this reason, the left and right parallax images can be visually recognized only by the respective eyes, thereby being visually recognized as a stereoscopic image.

  Hereinafter, the components constituting the laminate and the image forming body in the present invention will be described in more detail.

  The material of the thin film layer 3 has a property of disappearing by evaporation or sublimation due to heat, and it is sufficient that an image pattern can be formed by contrast between the disappeared portion and the other portions. There are no particular limitations on the pigment system, the polymer material, and the like. Uses a coating film obtained by wet coating by dissolving one or a combination of these materials in a solvent or dispersing on fine particles, or by dry coating such as vacuum deposition or sputtering. Is possible. Alternatively, a method in which a light absorbing material is added to a resin to form a thin film layer is also effective because the thin film layer can be eliminated with low energy. Further, a compound that promotes disappearance may be added, or this compound may be bonded to the resin skeleton.

  Among inorganic materials, materials for forming a thin film of metal, metal oxide, metal compound, etc. by vacuum deposition or sputtering as a thin film layer include Al, Sn, Cr, Ni, Cu. A single metal material such as Au or Ag or a compound thereof can be used. In particular, a thin film layer obtained by forming a film by a vacuum deposition method is advantageous for manufacturing a fine pattern as in the present invention because a thin film layer with high thickness accuracy can be obtained. Further, by using a metal, it is possible to draw a high contrast between the metal reflection portion where the thin film layer does not disappear and the disappeared non-reflection portion, and an image with good visibility can be formed.

As the high refractive index material serving as the transparency is thin _{layer, Sb 2 O 3 (3.0)} , Fe 2 O 3 (2.7), TiO 2 (2.6), CdS (2.6 ), CeO ₂ (2.3), ZnS (2.3), PbCl ₂ (2.3), CdO (2.2), Sb ₂ O ₃ (5), WO ₃ (5), SiO (5) , Si ₂ O ₃ (2.5), In ₂ O ₃ (2.0), PbO (2.6), Ta ₂ O ₃ (2.4), ZnO (2.1), ZrO ₂ (5) MgO (1), Si ₂ O ₂ (10), MgF ₂ (4), CeF ₃ (1), CaF ₂ (1.3 to 1.4), AlF ₃ (1), Al ₂ O ₃ (1 ), Ceramics such as GaO (2), polyethylene (1.51), polypropylene (1.49), polytetrafluoroethylene (1.35), polymethyl methacrylate (1.49), Polystyrene (1.60) organic polymers, and the like. The numerical value in parentheses following the chemical formula or compound name indicates the refractive index n. These materials are appropriately selected based on optical characteristics such as refractive index, reflectance, and transmittance, weather resistance, interlayer adhesion, and the like, and are formed in the form of a thin film.

  As a method for forming the thin film layer, a known method such as a vacuum evaporation method, a sputtering method, a CVD method, or the like that can control the film thickness, the film formation speed, the number of stacked layers, the optical film thickness, and the like can be appropriately used. It is also possible to apply high-gloss inks in which fine particles of these materials are dispersed in various solvents. In addition, high-brightness light-reflecting ink obtained by dispersing the above metal, ceramics, or organic polymer fine powder, sol, or metal particles in an organic polymer resin, organic polymer or organic polymer fine particles should be used. Is also possible. In this case, it is necessary to prevent the lens assembly layer and the focal length adjustment layer from being attacked by a solvent, but it can be formed by a known printing method such as a gravure printing method, a flexographic printing method, or a screen printing method. In addition, it is preferable that the contrast between the part where the thin film layer does not disappear and the part where the thin film layer disappeared is strong, visible dyes and pigments, fine particles for refractive index adjustment may be added to improve contrast due to the difference in refractive index, Invisible color materials such as fluorescent pigments and fluorescent dyes may be added. The film thickness of the thin film layer may be adjusted to be about 0.001 to 20 μm after drying, and may be a film thickness that can be lost depending on the power and line width of the laser beam used. It ’s fine. For example, an aluminum film thickness of 100 nm or less can be erased with laser light having an output of 1 W, a light emission width of 50 μm, and a frequency of 120 KHz.

  Further, the thin film layer may be provided partially. In this case, pasta processing, water-washed celite processing, laser processing, etc. are mentioned as examples, and for example, a fine sea island-shaped thin film layer is formed by vacuum deposition of tin or the like. It is also possible to provide.

  In the portion where the transparent thin film layer is disposed, visible information can be separately provided below the thin film layer, and the necessary information and the image forming body of the present invention can be laminated. . As a result, for example, the necessary information can be printed on an ID card, a passport, or the like, and the image forming body can be laminated to be applied as an anti-counterfeit oversheet. In this case, when the transmittance of the thin film layer is 20% or more in the wavelength region of 400 nm to 700 nm, the lower information may be easily visible.

  The lens assembly layer 2 has a structure in which lens-shaped portions having condensing elements are densely arranged on a plane, and typical examples include an eyelet lens, a microlens array, etc. The lens assembly layer in the invention is not limited to this, and a convex lens, a plano-convex lens, a biconvex lens, a meniscus convex lens, a convex cylindrical lens, a lenticular lens, a Fresnel lens, a diffraction lens, a spherical lens, or a combination of the above lenses It is also possible to use a lens assembly in which one or more compound lenses are densely arranged on a plane, a continuous film having the same surface shape as the lens assembly and having a condensing function.

  The material of the lens assembly layer is suitable for the application in consideration of light collecting properties, transparency, heat resistance, chemical resistance, wear resistance, etc. from organic materials, inorganic materials, organic inorganic composite materials, etc. What is necessary is just to select a material suitably. In particular, since the thin film layer is erased by the laser beam condensed by the lens assembly, heat resistance corresponding to the irradiation amount and irradiation frequency of the laser beam to be used is required. If the heat resistance does not satisfy the conditions, the lens may be deformed or altered by laser light irradiation during image recording. In addition, it is preferable that the plurality of lens shape portions constituting the lens assembly layer have the same shape, are periodically fine, and are integrated on a plane. Recording is possible even when lens shapes with different shapes are assembled, but if the focal lengths of the individual lenses are different, partial recording loss may occur. It is better to let them. Further, when there is no periodicity, or when they are not densely integrated, the recorded image pattern is not reproduced in the portion without the lens shape portion, so that the image pattern is partially lost.

  In the lens assembly layer, the lens-shaped portions are integrated on a plane in an arbitrary pattern area, or a plurality of lens assembly layers having different condensing functions are provided on the same plane in each pattern area. In this way, it is possible to obtain an image forming body that can be written only by a specific laser beam in a specific portion.

  As a method of forming the lens assembly layer, a dry etching method or a wet etching method, a method of manufacturing a microlens array by dripping a resin on a master plate on which a spherical surface corresponding to a lens is formed, solidifying and peeling the resin, It can be manufactured by a known manufacturing method such as a manufacturing method of a microlens array using surface tension, a manufacturing method of a microlens array in which a plurality of lens surfaces are formed on both sides, but is not limited thereto. is not. The lens assembly layer may be directly formed on the thin film layer or the focal length adjustment layer.

  The focal length adjustment layer 4 is disposed between the lens assembly layer and the thin film layer, and the interlayer distance is set so that the focal point of each lens-shaped portion constituting the laser assembly layer is located on the surface or inside of the thin film layer. It has a function to adjust. In addition, the thickness and shape of the focal point of the various laser incident angles with respect to the lens assembly layer is the surface or inside of the thin film layer, thereby suppressing distortion and blurring of the reproduced image due to the observation angle. Is also possible.

  The material of the focal length adjustment layer 4 may be any of an organic material, an inorganic material, and an organic-oriented composite material. However, since the laser beam is condensed at the interface with the thin film layer, it is necessary to eliminate the thin film layer. It is necessary to have heat resistance corresponding to the amount of laser light irradiation. As a method for forming the focal length adjustment layer, a known method such as a vacuum deposition method, a sputtering method, a CVD method, a wet coating, or a hot embossing method can be applied.

  Also, as shown in FIG. 4, a diffractive structure is formed in a part of the lower portion of the focal length adjusting layer, and the corresponding thin film layer is laminated so as to follow the shape of the focal length adjusting layer, whereby the thin film layer becomes a reflective layer. It is also possible to make a laminate having a vivid color change function depending on the observation angle. An image forming body in which an image pattern is recorded on such a laminate can obtain a vivid color change function by a relief type diffractive structure in a non-recording portion (a portion that does not disappear due to heat) of the diffractive structure thin film layer. In the recording portion (the portion disappeared by heat), the image pattern can be visually recognized as a three-dimensional image or a plurality of images, and the image recording body has high security and design.

  As a method for forming the diffractive structure, a known method such as a heat embossing method, a photopolymer method, or a composite method thereof can be used. For example, after forming a coating film of a thermoplastic resin by a wet coating method, After the thin film layer is laminated by coating, it can be formed by pressing the diffractive structure mold from the pattern thin film curved curve of the heated laminated coating film and transferring the shape.

  What is necessary is just to select the period of a diffraction structure suitably according to the wavelength range of the desired diffracted light. The depth of the diffractive structure is preferably as small as possible relative to the focal length of the lens assembly layer, and is preferably 10% or less of the focal length. Thus, by reducing the depth of the diffractive structure, it is possible to suppress variations in the degree of condensing of the laser light between the convex part and the concave part of the diffractive structure, so that a fine and stable image pattern can be recorded. Further, it is preferable to use a pulsed laser so that the unevenness of the diffractive structure is not destroyed by the heat of the laser beam. As the pulse becomes shorter, the thin film layer can be removed without increasing the temperature of the material, so that an image pattern can be recorded without breaking the diffraction structure.

The types of laser light used for recording an image pattern on the laminate of the present invention include a far infrared laser represented by a CO ₂ laser, a near infrared pulse laser represented by a Nd: YAG laser and a Nd: YVO laser. And an ultraviolet laser, a semiconductor laser, a femtosecond laser, a picosecond laser using a third harmonic of a visible light pulse laser, an excimer laser, an Nd: YAG laser, or an Nd: YVO laser. In particular, Nd: YAG laser and Nd: YVO laser are advantageous in high output and high pulse stability. In addition, the laser using the third harmonic of the Nd: YAG] laser or the Nd: YVO laser has advantages such as high resolution and UV light absorption of the marking material. In addition, since ultrashort pulse lasers such as femtosecond lasers and picosecond lasers can break molecular bonds without bringing the material to a high temperature state, recording (disappearance) can be performed without heat. A YAG or diode laser can emit a large amount of heat energy with a relatively small device, and can record an image pattern on demand. Further, it is also possible to collect or diffuse the laser beam to be irradiated for obtaining a beautiful reproduced image or adjusting the focal length. For this purpose, a known condensing element or light diffusing element may be used.

  In the image recording method of the image forming body according to the present invention, the laser light irradiated from the lens assembly layer side is condensed by each lens shape portion of the lens assembly layer, and the thin film layer is partially formed by the condensed laser light. Disappear and record. Note that by changing the irradiation angle of the laser beam on the image forming body, it is possible to record a plurality of images that are visible from each irradiation angle.

  In addition, the laser beam output, spot diameter, frequency, scanning speed, lens shape condensing action, lens so that the thin film layer does not disappear with the unfocused laser light, but disappears only with the collected laser light Adjust the focal length. By doing so, it is possible to prevent the contrast of the image pattern from being lowered by the laser light that has not passed through the lens-shaped portion. Further, an image forming body in which a lens assembly layer is provided in a pattern on the thin film layer is also possible.

  As an example of a method for recording a stereoscopic image using recording of a plurality of image patterns, there is a stereogram obtained by making it possible to reproduce a two-dimensional image at a certain angle of a three-dimensional object only from the angle. Such a stereogram original image may be obtained by using a plurality of two-dimensional images obtained by photographing a three-dimensional object from an arbitrary angle, and by recording the obtained two-dimensional images by laser irradiation from the photographed angle, Even when viewed from various angles, the reproduced image has a stereoscopic effect. As another example, a stereo that reproduces a stereoscopic image by binocular parallax is recorded by recording the left and right parallax images on the same plane and recording the left and right eyes so that only the left and right vision images are reproduced. Gram. As the original image of such a stereogram, a two-dimensional image obtained by photographing a right-view image and a left-view image may be used, and the obtained two two-dimensional images are taken from the angle at which the two images are photographed (positions of the left and right eyes). If it is difficult to irradiate with a laser, a reconstructed image with a three-dimensional feeling that feels the depth is obtained. These are one example of the image recording method of the present invention. In the image recording method of the present invention, the obtained reproduced image may be a two-dimensional multiple image, a two-dimensional animation (moving image), or a three-dimensional image. It is not limited to this.

  Further, a relief type diffractive structure layer and a reflective layer may be further laminated below the laminated body or an image forming body obtained by forming an image pattern on the laminated body.

  The relief-type diffractive structure layer is a layer forming a relief-type diffractive structure, and the materials thereof are polyvinyl chloride, acrylic resin (eg PMMA), thermoplastic resin such as polystyrene and polycarbonate, and unsaturated polyester. , Melamine, epoxy, polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate, melamine (meth) acrylate, triazine acrylate, etc. Each of these resins can be used alone, or a plurality of resins can be selected and mixed from the above thermoplastic resins and thermosetting resins, and further, a thermoformable substance having a radically polymerizable unsaturated group, or radical polymerization thereof. Ionizing radiation curable by adding an unsaturated monomer Were ones like can be used. In addition, photosensitive materials such as silver salt, dichromated gelatin, thermoplastic, diazo photosensitive material, photoresist, ferroelectric, photochromic material, thermochromic material, chalcogen glass, and the like can be used.

  As a method for forming the relief type diffractive structure layer, a known method can be used. For example, when recording interference fringes of diffraction gratings or holograms as reliefs of surface irregularities, the diffraction gratings or interference fringes have irregular shapes. As a pressing method, a relief type diffractive structure resin coating solution is applied to the protective layer of the laminated sheet in which the release resin layer and the protective layer are laminated in order on the support. The coating is formed by a means such as a roll coating method or a bar code method, and a coating film is formed. can do. Moreover, when using a photopolymer, after coating a photopolymer similarly on the protective layer of the said lamination sheet, it can duplicate by irradiating a laser beam, overlapping the said original plate. As described above, the method of recording the diffraction grating or hologram interference fringes on the surface of the relief type diffractive structure layer as the relief of the surface irregularities is particularly preferable in terms of mass productivity and low cost.

  The reflective layer is an optical thin film provided so as to cover the diffractive structure and to cover at least a portion where the diffractive structure of the diffractive structure thin film layer or the relief type diffractive structure layer is formed. The generated diffracted light is reflected. For this reason, it is also possible to obtain an optical effect by using a high refractive index material having a higher refractive index than that of the diffractive structure. In this case, the difference in refractive index between the diffractive structure and the reflective layer is preferably 0.2 or more. When the difference in refractive index is 0.2 or more, refraction and reflection occur at the interface between the diffractive structure and the reflection, and the optical effect due to the structure of the diffractive structure can be obtained.

  Examples of the material for the reflective layer include simple substances such as Al, Sn, Cr, Ni, Cu, Au, and Ag, or compounds thereof.

Examples of high refractive index materials that can be used as a reflective layer having transparency are given below. Sb ₂ O ₃ (3.0), Fe ₂ O ₃ (2.7), TiO ₂ (2.6), CdS (2.6), CeO ₂ (2.3), ZnS (2.3), PbCl ₂ (2.3), CdO (2.2), Sb ₂ O ₃ (5), WO ₃ (5), SiO (5), Si ₂ O ₃ (2.5), In ₂ O ₃ (2 0.0), PbO (2.6), Ta ₂ O ₃ (2.4), ZnO (2.1), ZrO ₂ (5), MgO (1), Si ₂ O ₂ (10), MgF ₂ ( 4), CeF ₃ (1), CaF ₂ (1.3 to 1.4), AlF ₃ (1), Al ₂ O ₃ (1), ceramics such as GaO (2), polyethylene (1.51), Organic polymers such as polypropylene (1.49), polytetrafluoroethylene (1.35), polymethyl methacrylate (1.49), polystyrene (1.60) and the like can be mentioned. The numerical value in parentheses following the chemical formula or compound name indicates the refractive index n. These materials are appropriately selected based on optical characteristics such as refractive index, reflectance, and transmittance, weather resistance, interlayer adhesion, and the like, and are formed in the form of a thin film. As a forming method, it is possible to use a known printing method such as a vacuum deposition method, a sputtering method, a CVD method or the like, which can control a film thickness, a film forming speed, the number of stacked layers, an optical film thickness, and the like. It is also possible to apply high-brightness inks in which the fine particles are dispersed in various solvents.

  In addition, high-brightness light-reflecting ink obtained by dispersing the above-mentioned metal, ceramics, or organic polymer fine powder, sol, or metal nanoparticles in an organic polymer resin, organic polymer or organic polymer fine particles should be used. You can also. In this case, care must be taken not to attack the diffractive structure with a solvent, but the diffractive structure can be formed by a known printing method such as a gravure printing method, a flexographic printing method, or a screen printing method. In addition, what is necessary is just to adjust the film thickness of a reflection layer so that it may become about 0.001-10 micrometers in the state after drying.

  In addition, the reflective layer may be provided partially. In this case, pasta processing, water-washed sealight processing, laser processing, etc. can be mentioned as examples. In addition, for example, a fine sea-island reflective layer is formed by vacuum deposition of tin or the like. It is also possible to provide.

  In the portion where the reflective layer having transparency is arranged, visible information can be separately provided below the reflective layer, and the necessary information and the image forming body of the present invention can be laminated. is there. As a result, for example, necessary information and the like can be printed on an ID card, a passport, and the like, and the image forming body can be applied as a seat starter, an anti-counterfeit oversheet, and the like. In this case, when the transmittance of the reflective layer is 20% or more in the wavelength region of 400 nm to 700 nm, the lower information may be easily visible.

  As another example, a volume hologram layer may be provided below the laminated body or an image forming body obtained by recording an image pattern on the laminated body. The volume hologram layer is a layer capable of recording information in the thickness direction and capable of recording / reproducing a three-dimensional image. Although the manufacturing method of the volume hologram layer itself is already known, imitation is difficult because it requires precise work using an optical device in manufacturing, and further security is provided by providing a volume hologram layer. It is possible to add. Further, since the volume hologram layer is expressed by the interference color of light, it has an appearance that is difficult to obtain with other image forming means.

  Examples of the material for the volume hologram layer include photopolymer materials and the like, and can be said to be suitable for industrial production of volume holograms because volume holograms can be recorded by a dry process. Photopolymer materials include, for example, liquid radical polymerizable compounds, solid radical polymerizable compounds as refractive index modulation forming materials, and high refractive index radical polymerizable compounds and low refractive index liquid cationic polymerizable compounds that are refracted. Various materials such as a system using a rate modulation forming material and a system using a thermosetting epoxy oligomer and a liquid radical polymerizable compound as a refractive index modulation forming material have been proposed, but not limited thereto.

  The volume hologram layer is formed by, for example, applying a volume hologram photosensitive resin composition to a support film so as to have a film thickness of 10 μm after drying to obtain a volume hologram forming layer, and then forming a volume hologram layer. The layer is brought into close contact with the mirror original plate, and an argon ion laser beam (wavelength 514.4 nm) is incident at 35 ° from the normal direction of the dry coating film, and incident light and reflected light are interfered to record a volume hologram (hologram mirror). Then, a method of obtaining a volume hologram layer fixed by heating, ultraviolet fixing exposure or the like can be mentioned. As a support film (not shown) for applying the volume hologram forming material, a polyethylene terephthalate film (common name: PET film) having a thickness of 1 μm to 1 mm, preferably 10 μm to 100 μm, a polyethylene film, a polypropylene film, a poly A vinyl chloride film, an acrylic film, a triacetyl cellulose film, a cellulose acetate butyrate film, or the like is used. As the support film, it is desirable to use a film having high transparency and high smoothness. However, the method for forming the volume hologram layer in the present invention is not limited to this.

  Furthermore, a barrier layer can be provided between the volume hologram layer and the adjacent layer. For example, when a release layer or a heat-sensitive adhesive layer is provided on the volume hologram layer side of the image forming body of the present invention, the low molecular weight component is transferred from the volume hologram layer to the adjacent layer over time depending on the combination. The peak of the hologram recorded due to this shifts to the blue side (short wavelength side), and when it shifts to the release layer, the peeled product may be changed. . Therefore, these barrier factors can be eliminated by providing a barrier layer.

The material used for the barrier layer is not particularly limited as long as it exhibits a barrier property, and a transparent organic resin material can be used. Among them, use is made of a solvent-free trifunctional desk, preferably an ionizing radiation-curable epoxy-modified acrylate resin, urethane-modified acrylate resin, acrylic-modified polyester resin, etc. that reacts with ionizing radiation such as ultraviolet rays and electron beams, which is 6 or more functional groups. And good. Of these, urethane-modified acrylate resins are preferred because of their high barrier properties. Further, the ionizing radiation curable resin that reacts with these ionizing radiations preferably has a molecular weight in the range of 500 to 2,000 in view of the suitability of the coating, the altitude of the finally obtained barrier layer, and the like.

  In addition, when laminating a relief type diffractive structure layer and a reflective layer, or a volume hologram layer below the laminate, the relief type diffractive structure layer, the reflective layer, or the volume is not disturbed so as not to prevent the thin film layer from being lost by laser light. It is necessary to adjust the film thickness of the hologram layer, and in reality, disappearance was confirmed when the film thickness was 150 nm or less.

  As described above, each member has been described in detail based on the embodiment of the present invention. However, each layer is colored to improve the designability, printing is performed between the front and back surfaces or the layers, and the pattern is installed. It can be appropriately used depending on the purpose of use, such as applying an overcoat that makes the step of any layer inconspicuous. In view of the adhesiveness of each layer, it is also possible to provide an adhesive layer and an adhesive anchor layer between the respective layers, and to perform various easy adhesion treatments such as corona discharge treatment, plasma treatment, and frame treatment. In addition, a heat-resistant layer may be provided between arbitrary layers in order to reduce substrate damage due to heat during laser processing, and a focus adjustment layer for adjusting the focus of the laser may be provided between arbitrary layers.

  Furthermore, for the purpose of removing light other than the diffracted light of the diffractive structure, a black layer (light absorption layer) and a colored layer (specific wavelength absorption layer) are provided on the entire surface or in an arbitrary pattern under the image forming body. Alternatively, a reflection layer or a scattering layer for reflecting and scattering light other than the diffracted light of the diffractive structure to the regular reflection direction may be provided separately. Further, a protective layer or an antireflection structure may be provided on the outermost layer as long as the lens function is not hindered.

<Example 1>
A lens assembly aligned in a hexagonal close-packed pattern of φ5.0 mm hemispheres by injecting and cooling acrylic resin melted by injection molding using a mold in which φ5.0 mm hemispheres are arranged in a hexagonal close-packed method A layer was made. A thin film layer was formed by depositing aluminum with a thickness of 80 nm below the obtained lens assembly layer by a vacuum vapor deposition method to obtain a laminate.

<Example 2>
A mold in which φ0.5 mm hemispheres are arranged in a hexagonal close-packed method was formed, and aligned with a hexagonal close-packed pattern of φ0.5 mm hemispheres directly on an aluminum-deposited PET film (Toray Metal Me 25 μm) by a photopolymer method. A lens assembly layer was formed to obtain a laminate.

<Example 3>
A laminate was obtained in the same manner as in Example 2 except that a mold in which φ0.1 mm hemispheres were arranged in a hexagonal close-packing method was used.

<Example 4>
After arranging glass beads of φ0.5 mm on a plane by an hexagonal close-packing method on an aluminum-deposited PET film (Toray Metal Me 25 μm), a polyester transparent resin was applied to fix the glass beads to obtain a laminate. .

<Example 5>
On the plane side of a lenticular lens sheet having a radius of curvature of 50 microns and 130 μm from the lens apex position to the back surface, aluminum was produced with a film thickness of 80 nm by vacuum deposition, and a thin film layer was provided to obtain a laminate.

For the laminates obtained in Examples 1 to 5, an image pattern was recorded by using a laser marker (Keyence YAG pulse laser) to obtain an image forming body. In recording the image pattern, a real image 1 was recorded by laser irradiation from the vertical direction, and an image 2 was recorded by laser irradiation from a 30 ° oblique direction from the perpendicular. The laser irradiation conditions are as follows.
Scanning speed: 500mm / s
Laser power: 5%
Line width: 0.2mm
Number of lines: 4

  The image forming body on which the image pattern was recorded by the above method confirmed the image 1 when confirmed from the vertical direction, and confirmed the image 2 when observed from an oblique direction 30 ° from the perpendicular.

It is sectional drawing which shows the basic structure of the laminated body which concerns on this invention. It is sectional drawing which shows 1st embodiment of the laminated body which concerns on this invention. It is sectional drawing which shows 2nd embodiment of the laminated body which concerns on this invention. It is sectional drawing which shows the example of 3rd embodiment of the laminated body which concerns on this invention. It is a figure which shows the process of recording an image pattern with respect to the laminated body shown in FIG. It is a figure which shows the process of recording an image pattern with respect to the laminated body shown in FIG. FIG. 3 is a diagram showing how an image forming body formed by recording two image patterns on the laminated body shown in FIG. 2. It is a figure which shows the manufacturing method of the image forming body formed by recording a stereo image with respect to the laminated body shown in FIG. It is a figure showing the reproduction | regeneration state of the stereo image at the time of observing the image forming body of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1, Laminated body 2, Lens assembly layer 3, Thin film layer 4, Focal length adjustment layer 5, Diffraction structure thin film layer 6, Image forming body 7, Laser beam 8 which irradiates a right-view image pattern 8, Irradiates a left-view image pattern Laser light

Claims (4)

A focal length having at least a part of a lens assembly layer in which a plurality of lens-shaped portions are densely arranged on a plane and a thin film layer positioned below the lens assembly layer, and at least a part of which has a diffraction structure formed A method for producing an image forming body, wherein an image pattern is formed by recording an image pattern on the thin film layer of a laminate having an adjustment layer between the lens assembly layer and the thin film layer,
An image pattern is recorded by irradiating the laminated body with laser light from a certain direction on the lens assembly layer side, condensing the laser light onto the thin film layer through the lens, and partially erasing the thin film layer. A method for producing an image forming body characterized by the above.   2. The method of manufacturing an image forming body according to claim 1, wherein the laser beam irradiation from a predetermined direction is performed on the laminated body from a plurality of different angles.   The method for producing an image forming body according to claim 1, wherein the thin film layer has a property of being sublimated or evaporated by heating. It has at least a lens assembly layer in which a plurality of lens-shaped portions are arranged densely on a plane, and a thin film layer positioned below the lens assembly layer, and a relief type diffractive structure is formed at least in part. A laminated body having a focal length adjustment layer between the lens assembly layer and the thin film layer, wherein the focal length adjustment layer is a film thickness at which the focal point of the laser light irradiated from the lens shape portion direction becomes a thin film layer And the thin film layer has a property of evaporating or sublimating by heating, and an image forming layer in which a plurality of image patterns are recorded is formed at a laser beam focal position of the thin film layer. .