JP6024794B2 - Method for producing fine particle-containing sheet - Google Patents

Description

  The present invention relates to a technique for preventing forgery by fine particles.

  In recent years, there has been a demand for anti-counterfeiting techniques that are difficult to forge and that can be easily determined. As such anti-counterfeiting techniques, holograms, watermarks, latent image patterns, pearl inks, luminescent inks, intaglio printing, micro characters, and the like are known. However, anti-counterfeiting technologies such as holograms whose presence is clear at first glance have a problem that counterfeiting is easy. Therefore, anti-counterfeiting technology that uses information that cannot be confirmed visually (with the naked eye) has attracted attention. On the other hand, since printing technology has recently developed and high-definition printing is possible, even if the information cannot be confirmed visually, the possibility of being forged increases if the position of the information is specified. There's a problem.

  Therefore, forgery prevention technology using fine particles has been proposed. These fine particles are also called taggant (additive for tracking), and when used in an article, the position of the fine particles differs depending on the individual, so it is difficult to confirm the fine particles themselves and to copy them. Therefore, advanced anti-counterfeiting can be realized. In addition, the individual can be identified.

  The fine particles are known to have information that can be identified by magnifying and observing, for example, fine particles having symbols such as letters, numbers, codes, marks, and special shapes, and colored thin films. Have been proposed (see, for example, Patent Documents 1 to 4). For fine particles having a symbol or special shape, authenticity can be determined by enlarging and identifying the symbol or special shape. Further, in the fine particles in which a plurality of colored thin films are laminated, it is possible to determine the authenticity by identifying the enlarged and laminated color pattern.

Japanese Patent No. 3665282 JP 2008-230228 A JP 2009-193069 A JP 2001-288698 A

When the fine particles are fixed to an article, ink or toner containing the fine particles is generally applied to the article. However, in order to reliably use fine particles in articles, it is necessary to increase the content of fine particles in ink and toner, or to increase the amount of ink and toner used, and the fine particles are expensive. It is disadvantageous in terms of cost. Moreover, in order to ensure that fine particles are reliably used in an article, individual inspections are required, and it is not easy to perform 100% inspection.
In addition, in order to ensure the use of fine particles in the article, a method of directly adhering the fine particles to the article using an adhesive is also conceivable. However, the portion where the fine particles are fixed is raised and uneven, resulting in the use of fine particles. There is a problem that it is easy to understand that this is done.

  The present invention has been made in view of the above circumstances, and enables fine use of fine particles in an article, facilitates inspection that fine particles are used in an article, and has high anti-counterfeiting properties. The main object is to provide a method for producing a containing sheet.

  In order to achieve the above object, the present invention provides a fine particle-containing sheet having a fine particle-containing layer forming step of forming a fine particle-containing layer in which fine particles having information identifiable by magnifying observation are dispersed in a transparent resin The fine particle-containing layer forming step is a fine particle spraying step of spraying the fine particles on a substrate, and a transparent resin composition is disposed on the base material on which the fine particles are sprayed. Provided is a method for producing a fine particle-containing sheet, comprising a resin composition arranging step and a solidifying step for solidifying the transparent resin composition.

  Further, the present invention is a method for producing a fine particle-containing sheet having a fine particle-containing layer forming step of forming a fine particle-containing layer in which fine particles having information identifiable by magnifying observation are dispersed in a transparent resin, The fine particle-containing layer forming step includes a transparent resin composition arranging step of arranging a transparent resin composition on a substrate, and a fine particle spraying of dispersing the fine particles on the substrate on which the transparent resin composition is arranged. The manufacturing method of the microparticles | fine-particles containing sheet | seat characterized by including the process and the solidification process of solidifying the said transparent resin composition is provided.

In the fine particle-containing sheet produced according to the present invention, since the fine particle-containing sheet itself can be inspected in advance before being used for an article, there is an advantage that it is not necessary to inspect each article and the inspection is easy. .
In the present invention, as described above, since the fine particle-containing sheet itself can be inspected in advance before being used in an article, it is possible to ensure that fine particles are reliably used in the article. In addition, when a conventional ink containing fine particles is used to form a fine particle-containing layer by applying ink containing fine particles and a transparent resin composition on a substrate, the content of the fine particles in the fine particle-containing layer is grasped. In particular, when the content of fine particles in the ink is small and the amount of ink used is small, it is difficult to ensure that the fine particle-containing layer surely contains fine particles. On the other hand, according to the present invention, after the fine particles are dispersed on the substrate, the transparent resin composition is disposed, or the fine resin particles are dispersed after the transparent resin composition is disposed on the substrate. It is possible to easily grasp the content of the fine particles therein, and it is possible to reliably contain the fine particles in the fine particle-containing layer. Therefore, it is possible to reliably achieve the forgery preventing effect. Furthermore, it is possible to map the number and position of fine particles in the fine particle-containing sheet, and it can be used for articles with the number and position of the fine particles determined in advance, so it is possible to realize advanced anti-counterfeiting It is.

  In the said invention, it is preferable that the easily bonding process is given to the surface of the said base material. This is because the adhesion between the base material and the fine particle-containing layer can be enhanced, and the strength of the fine particle-containing sheet can be enhanced by the base material.

  Moreover, in this invention, it is preferable that the said base material is a transparent resin base material. This is because if the base material is a transparent resin base material, the fine particle-containing sheet can be used without peeling off the base material.

  Furthermore, the manufacturing method of the fine particle containing sheet | seat of this invention may have the base material peeling process which peels the said base material after the said fine particle content layer formation process. This is because the fine particle-containing layer can be obtained alone. The fine particle-containing layer can be easily laminated with other layers, and a high-value-added fine particle-containing sheet can be obtained. In addition, it is possible to reduce the thickness of the fine particle-containing sheet by peeling the base material.

  In the present invention, the transparent resin composition is preferably a curable resin composition. This is because the viscosity of the curable resin composition is relatively easy to adjust and the viscosity can be lowered. If the viscosity of the transparent resin composition is low, the transparent resin composition is formed on the base material while maintaining the dispersed state of the fine particles dispersed on the base material in the order of the fine particle spraying step and the transparent resin composition arranging step. It becomes easy to arrange objects. Moreover, when performing in order of a transparent resin composition arrangement | positioning process and a fine particle dispersion | spreading process, it becomes easy to disperse | distribute microparticles | fine-particles uniformly in the film | membrane which consists of a transparent resin composition.

  Furthermore, in the present invention, the transparent resin composition preferably contains at least one selected from the group consisting of an ultraviolet light emitting material, an infrared light emitting material, an infrared reflecting material, an infrared absorbing material, and a quantum dot material. This is because the fine particles can be easily seen, authenticity determination is facilitated, and the effect of preventing forgery can be improved.

  In the present invention, there is an effect that inspection is easy and the fine particle-containing layer can surely contain fine particles.

It is process drawing which shows an example of the manufacturing method of the fine particle containing sheet | seat of this invention. It is the top view and sectional drawing which show an example of the microparticles | fine-particles used for this invention. It is the top view and sectional drawing which show the other example of the microparticles | fine-particles used for this invention. It is the top view and sectional drawing which show the other example of the microparticles | fine-particles used for this invention. It is the perspective view and side view which show the other example of the microparticles | fine-particles used for this invention. It is sectional drawing which shows the other example of the microparticles | fine-particles used for this invention. It is a schematic sectional drawing which shows an example of the fine particle containing sheet | seat manufactured by this invention. It is a schematic sectional drawing which shows the other example of the fine particle containing sheet | seat manufactured by this invention. It is a schematic sectional drawing which shows the other example of the fine particle containing sheet | seat manufactured by this invention. It is a schematic sectional drawing which shows the other example of the fine particle containing sheet | seat manufactured by this invention. It is a schematic sectional drawing which shows the other example of the fine particle containing sheet | seat manufactured by this invention. It is a schematic diagram which shows an example of the inspection method of the fine particle containing sheet | seat manufactured by this invention. It is the upper side figure and sectional drawing which show an example of the forgery prevention medium provided with the fine particle containing sheet | seat manufactured by this invention. It is a top view, sectional drawing, and perspective view showing other examples of a forgery prevention medium provided with a fine particle content sheet manufactured by the present invention. It is process drawing which shows the other example of the manufacturing method of the fine particle containing sheet | seat of this invention.

  Hereinafter, the manufacturing method of the fine particle containing sheet | seat of this invention is demonstrated in detail.

The method for producing a fine particle-containing sheet of the present invention is a method for producing a fine particle-containing sheet having a fine particle-containing layer forming step of forming a fine particle-containing layer in which predetermined fine particles are dispersed in a transparent resin, wherein the fine particle-containing layer is formed. The process includes a fine particle spraying process for spraying predetermined fine particles on the substrate, a transparent resin composition arranging process for arranging the transparent resin composition on the substrate, and a solidifying process for solidifying the transparent resin composition. It is characterized by.
The method for producing the fine particle-containing sheet of the present invention can be divided into two embodiments according to the order in which the fine particle spraying step and the transparent resin composition arranging step are performed.
In the following, each embodiment will be described separately.

I. First Embodiment The method for producing a fine particle-containing sheet of this embodiment includes a fine particle-containing layer forming step of forming a fine particle-containing layer in which fine particles having information that can be identified by magnifying and observing are dispersed in a transparent resin. A method for producing a fine particle-containing sheet, wherein the fine particle-containing layer forming step comprises: a fine particle spraying step for spraying the fine particles on a base material; and a transparent resin composition on the base material on which the fine particles are sprayed. A transparent resin composition arranging step for arranging the solid resin, and a solidifying step for solidifying the transparent resin composition.

A method for producing the fine particle-containing sheet of the present embodiment will be described with reference to the drawings.
1A to 1F are process diagrams showing an example of a method for producing a fine particle-containing sheet of this embodiment. First, as shown to Fig.1 (a), the predetermined fine particle 3 is spread | dispersed on the base material 2 in which the spacer 11 was formed (fine particle dispersion | distribution process). Next, as shown in FIG. 1B, the transparent resin composition 4a is injected onto the base material 2 on which the fine particles 3 are dispersed (transparent resin composition arranging step). Subsequently, as shown in FIG. 1C, the transparent resin composition 4a is covered with a flat substrate 12 such as a cover glass and planarized. Next, in this state, the transparent resin composition 4a is solidified (solidification step). Thereby, as shown in FIG.1 (d), the fine particle content layer 5 by which the fine particle 3 was disperse | distributed in the transparent resin 4b is obtained (fine particle content layer formation process). Next, as shown in FIG. 1 (e), the flat substrate 12 and the spacer 11 are peeled from the fine particle-containing layer 5, and further, as shown in FIG. 1 (f), the fine particle-containing layer 5 is peeled from the substrate 2. (Substrate peeling step). In this way, the fine particle-containing sheet 1 can be obtained.

  In the fine particle-containing sheet produced according to the present embodiment, the fine particle-containing sheet itself can be inspected in advance before being used for an article, so there is no need to inspect each article, and the advantage that the inspection is easy is provided. Have.

In addition, in the fine particle-containing sheet produced according to this embodiment, as described above, the fine particle-containing sheet itself can be inspected in advance before being used in the article, so that the fine particles are reliably used in the article. It can be guaranteed. In addition, when a conventional ink containing fine particles is used to form a fine particle-containing layer by applying ink containing fine particles and a transparent resin composition on a substrate, the content of the fine particles in the fine particle-containing layer is grasped. In particular, when the content of fine particles in the ink is small and the amount of ink used is small, it is difficult to ensure that the fine particle-containing layer surely contains fine particles. On the other hand, according to this embodiment, since the transparent resin composition is disposed after the fine particles are dispersed on the base material, the content of the fine particles in the fine particle-containing layer can be easily grasped, and the fine particle-containing It becomes possible to reliably contain fine particles in the layer. Therefore, it is possible to reliably achieve the forgery preventing effect.
Furthermore, in the fine particle-containing sheet produced according to this embodiment, it is possible to perform mapping for the number and position of the fine particles, and the number and position of the fine particles can be used in the article in a predetermined state. It is possible to realize advanced anti-counterfeiting.

  Moreover, unlike the ink and toner containing fine particles, the fine particle-containing sheet produced according to this embodiment has an advantage that it can be easily fixed to an article and has excellent handleability. Furthermore, the fine particle-containing sheet produced according to this embodiment can be easily laminated with other sheets, and a high-value-added fine particle-containing sheet can be obtained.

  Hereinafter, each process in the manufacturing method of the fine particle containing sheet | seat of this embodiment is demonstrated.

1. Fine particle-containing layer forming step The fine particle-containing layer forming step in this embodiment is a step of forming a fine particle-containing layer in which fine particles having information that can be identified by magnifying and observing are dispersed in a transparent resin. A fine particle spraying step for spraying the fine particles on the material, a transparent resin composition arranging step for placing the transparent resin composition on the base material on which the fine particles are spread, and a solidification for solidifying the transparent resin composition Process.
Hereinafter, each step in the fine particle-containing layer forming step will be described.

(1) Fine particle spraying step The fine particle spraying step in this embodiment is a step of spraying fine particles having information that can be identified by magnifying and observing on a base material.
Hereinafter, the fine particle spraying method, the fine particles, and the base material will be described.

(A) Fine particle spraying method The fine particle spraying method in the present embodiment is not particularly limited as long as it is a method capable of uniformly spraying predetermined fine particles on a substrate. Any of the spraying methods can be used.
Examples of the dry spraying method include a method of spreading fine particles as they are, a method of spraying fine particles together with a gas, and the like. The gas is not particularly limited, and examples thereof include air and inert gas. Examples of the inert gas include rare gas elements such as helium, neon, and argon, and nitrogen. Among them, it is preferable to use nitrogen that is easy to handle.
Examples of the wet spraying method include a method in which the fine particles are mixed with a solvent and sprayed, and then the solvent is volatilized. The solvent is not particularly limited as long as it has volatility, fine particles are dispersed, and the fine particles do not dissolve, but ethanol, methanol, etc. are particularly considered in consideration of the environmental impact during volatilization. It is preferable to use a mixed liquid of polar volatile solvent such as 2-propanol and water.
When spraying the fine particles, the fine particles may be charged.

The amount of the fine particles dispersed on the base material is not particularly limited as long as the authenticity determination by the fine particles is possible when the fine particle-containing sheet produced according to the present embodiment is used for the forgery prevention medium, It is preferable that at least one fine particle is dispersed per 1 cm ^{2 of the} substrate surface.

(B) Fine particles The fine particles used in the present embodiment have information that can be identified by magnifying and observing.

  In addition, “identifiable by magnifying and observing” is difficult to identify by visual observation, and can be identified by magnifying and observing using a simple magnifier such as a magnifying glass or a microscope. It means that.

  The fine particles are not particularly limited as long as they have information that can be identified by magnifying and observing, and general fine particles can be used. The information is not particularly limited as long as it can be identified by magnifying and observing. Symbols such as letters, numbers, signs, marks, designs such as shapes, patterns, colors, etc. Any information can be used. These pieces of information can be information adapted to the use of the fine particle-containing sheet of the present embodiment, and can be information expressing a predetermined meaning.

Specific examples of the fine particles will be given. The fine particles are not limited to the following examples.
2A and 2B are schematic views showing examples of fine particles, FIG. 2A is a top view, and FIG. 2B is a cross-sectional view taken along line AA in FIG. 2A. The fine particles 3 shown in FIGS. 2A and 2B have concave portions formed in a pattern on the surface, and have information 32 (star symbol) that can be identified by magnifying and observing. ing.
3 (a) and 3 (b) are schematic views showing other examples of fine particles, FIG. 3 (a) is a top view, and FIG. 3 (b) is a sectional view taken along the line BB in FIG. 3 (a). is there. The fine particles 3 shown in FIGS. 3A and 3B have a three-dimensional shape on the surface, and have information 32 (three-dimensional shape of the teapot) that can be identified by magnifying and observing.
4 (a) and 4 (b) are schematic views showing other examples of fine particles, FIG. 4 (a) is a top view, and FIG. 4 (b) is a sectional view taken along the line CC in FIG. 4 (a). is there. The fine particles 3 shown in FIGS. 4 (a) and 4 (b) have a three-dimensional shape on the surface and concave portions formed in a pattern, and information 32a (teapot information) that can be identified by magnifying and observing. 3D shape) and 32b (TEA characters).
FIGS. 5A to 5C are schematic views showing other examples of fine particles. FIGS. 5A and 5B are perspective views and FIG. 5C is a side view. Each of the fine particles 3A to 3C shown in FIGS. 5A to 5C has a three-dimensional shape on its surface, and can be identified by observing information 32 (three-dimensional shape of letters D, N, and P). have.

  The fine particles may have one information as illustrated in FIG. 3A, or may have two or more information as illustrated in FIG. 4A. Further, as the fine particles, one type of fine particles having the same information may be used, or two or more types of fine particles having different information may be used. When the fine particles have two or more pieces of information and two or more kinds of fine pieces having different information are used, at least one of the two or more pieces of information may be the same. The information may be different. When two or more kinds of fine particles are used, the fine particles can be used in combination so as to express a predetermined meaning.

  The size of the information is not particularly limited as long as it can be identified by magnifying and observing, but is preferably 300 μm or less, more preferably 250 μm or less. This is because if the size of the information is too large, it can be visually observed and the forgery prevention effect may be reduced. The size of the information is preferably observable using a simple magnifier such as a loupe, and specifically, it is preferably 50 μm or more. This is because if it is possible to observe with a simple instrument such as a simple magnifier, the authenticity can be easily determined. The size of information may be 50 μm or less. In this case, authentication with a simple instrument is difficult, but observation with a microscope or the like is possible. As information becomes smaller, confidentiality increases. In addition, if the information becomes small, the manufacturing becomes difficult and the forgery prevention effect is also enhanced.

  Further, the particle diameter of the fine particles is not particularly limited as long as it can be observed by enlarging, but specifically, it is preferably 300 μm or less, and more preferably 250 μm or less. If the particle size of the fine particles is too large, the particles can be visually observed, and the position of the fine particles is specified when used in the anti-counterfeit medium, which may reduce the anti-counterfeit effect. The particle diameter of the fine particles is preferably observable with a simple magnifier such as a magnifying glass, specifically 50 μm or more. This is because if it is possible to observe with a simple instrument such as a simple magnifier, the authenticity can be easily determined. Further, if the particle size of the fine particles is too small, it may be difficult to form a three-dimensional shape on the surface of the fine particles. The size of information may be 50 μm or less. In this case, judgment with a simple instrument becomes difficult, but observation with a microscope is possible. Confidentiality is increased by reducing the particle size of the fine particles. In addition, if the particle size of the fine particles is small, it becomes difficult to manufacture, so that the effect of preventing forgery is enhanced.

  The particle size is generally used to indicate the particle size of the particle, and is a value measured by a laser method in the present invention. The laser method is a method of measuring an average particle size, a particle size distribution, and the like by dispersing particles in a solvent and thinning and calculating scattered light obtained by applying a laser beam to the dispersion solvent. The particle size is a value measured using a particle size analyzer Microtrac UPA Model-9230 manufactured by Leeds & Northrup as a particle size measuring device by a laser method.

  The fine particles may be colorless or colored, and are appropriately selected according to the material of the fine particles described later. When the fine particles are colored, the fine particles are easily visible and can be easily identified.

  The fine particles may or may not have light permeability, and are appropriately selected according to the material of the fine particles described later. When the fine particles do not have optical transparency, the fine particles can be easily seen and identified.

The material for the fine particles is not particularly limited as long as the material can produce fine particles having the above information, and for example, a metal, a metal compound, a resin, or the like can be used. The metal and the metal compound are not particularly limited as long as they can be formed by vapor deposition, plating, or sputtering. As the metal compound, metal oxide, metal sulfide, and the like are used. Examples of the metal compound include Al, ZnS, TiO ₂ , Cu, Au, and Pt. Examples of the resin include a curable resin such as a photocurable resin and a thermosetting resin, a thermoplastic resin, and a photosensitive resin.

  When using a resin, functional materials such as an ultraviolet light emitting material, an infrared light emitting material, an infrared reflecting material, an infrared absorbing material, a quantum dot material, a magnetic material, and a coloring material, which will be described later, may be added to the resin. It is possible to easily recognize the fine particles, to easily determine the authenticity, and to improve the forgery prevention effect. In addition, the resin can be finely processed and can improve production efficiency.

  The resin preferably has solvent resistance, and in particular, when the transparent resin composition to be described later contains a solvent, the resin is volatile, and the volatility used when fine particles are sprayed by a wet spraying method. It is preferably insoluble in the solvent.

  Among the resins, a photosensitive resin is particularly preferable. This is because the fine particles can be produced with good productivity and at low cost. As the photosensitive resin, either a positive photosensitive resin or a negative photosensitive resin can be used.

  When the fine particles contain a resin, the fine particles 3 preferably have a resin layer 33 and a metal layer 34 formed on the resin layer 33, as illustrated in FIG. This is because the formation of the metal layer on the surface of the fine particles makes it easy to visually recognize the information held by the fine particles due to the reflection of light, facilitates authenticity determination, and improves the forgery prevention effect. In the fine particle-containing layer in which fine particles are dispersed in a transparent resin, when the fine particles are made of resin, the difference in refractive index between the fine particle resin and the transparent resin is small, so that the interface between the fine particles and the transparent resin Although it is difficult to see and it is difficult to visually recognize the information that the fine particles have, it is possible to improve the visibility of the information that the fine particles have by forming a metal layer on the resin layer. Because it becomes.

As the material for the resin layer, the above-mentioned resins can be used. Moreover, said metal and metal compound can be used as a material of a metal layer.
An example of a method for forming the metal layer is a vapor deposition method.
The thickness of the metal layer is not particularly limited as long as it can improve the visibility of information held by the fine particles, and can be, for example, about 1 nm to 100 nm, and within the range of 10 nm to 250 nm. Preferably there is. If the metal layer is too thick, the information possessed by the fine particles may be impaired. If the metal layer is too thin, it is difficult to form the metal layer, or the effect of enhancing the visibility of the information possessed by the fine particles is sufficient. This is because it may not be obtained.

When the fine particles contain a resin, the fine particles contain a functional material such as an ultraviolet light emitting material, an infrared light emitting material, an infrared reflecting material, an infrared absorbing material, a quantum dot material, a magnetic material, or a coloring material such as a pigment or a dye. Is preferred. This is because, as described above, it is easy to visually recognize the fine particles and it is easy to determine the authenticity. Among these, the fine particles preferably contain at least one selected from the group consisting of an ultraviolet light emitting material, an infrared light emitting material, an infrared reflecting material, an infrared absorbing material, a quantum dot material, and a magnetic material. This is because these materials can be identified by the characteristics of the material and can improve the anti-counterfeit effect. In particular, the fine particles preferably contain at least one selected from the group consisting of an ultraviolet light emitting material, an infrared light emitting material, and a quantum dot material. This is because identification is possible by light emission, and authenticity determination can be performed more easily.
Hereinafter, the functional materials will be described separately.

(Ultraviolet light emitting material)
As the ultraviolet light emitting material used in this embodiment, a material that emits fluorescence by absorbing ultraviolet light can be used. As the ultraviolet light-emitting material, either a material that emits light by absorption in a short wavelength region (about 200 nm to 300 nm) or a material that emits light by absorption in a long wavelength region (about 300 nm to 400 nm) can be used. This ultraviolet light emitting material is excited by ultraviolet light and has a spectrum peak emitted when returning to a lower energy level in the wavelength range such as blue, green, red, etc., and should be selected appropriately according to the purpose. Can do. Specific examples include Ca ₂ B ₅ O ₉ Cl: Eu ²⁺ , CaWO ₄ , ZnO: Zn, Zn ₂ SiO ₄ : Mn, Y ₂ O ₂ S: Eu, ZnS: Ag, YVO ₄ : Eu, Y _2. O ₃ : Eu, Gd ₂ O ₂ S: Tb, La ₂ O ₂ S: Tb, Y ₃ Al ₅ O ₁₂ : Ce, Sr ₅ (PO ₄ ) ₃ Cl: Eu, 3 (Ba, Mg) O · 8Al ₂ O ₃ : Eu, Zn ₂ GeO ₄ : Mn, Y (P, V) O ₄ : Eu, 0.5MgF ₂ · 3.5MgO · GeO ₂ : Mn, ZnS: Cu, ZnS: Mn and the like. These may be used alone or in combination of two or more. Note that the composition of the ultraviolet light-emitting material is expressed by connecting the main component and the activator or the light emission center with “:”.

  The content of the ultraviolet light emitting material in the fine particles is not particularly limited as long as it can be distinguished by light emission, and can be about 1% by mass to 50% by mass.

(Infrared light emitting material)
As the infrared light emitting material used in this embodiment, a material that emits fluorescence by absorbing infrared light can be used. The infrared light emitting material is excited by infrared light (about 800 nm to 1200 nm) and emits visible light (about 400 nm to 800 nm), and can be appropriately selected depending on the purpose. Specific examples include YF ₃ : Yb + Er, YF ₃ : Yb + Tm, BaFCl: Yb + Er, and the like. In addition, the said infrared luminescent material has described the composition by connecting a main component, an activator, or a luminescent center by ":".

  The content of the infrared light emitting material in the fine particles is not particularly limited as long as it can be identified by light emission, and can be about 1% by mass to 50% by mass.

(Infrared reflective material)
As the infrared reflecting material used in the present embodiment, a material having wavelength selective reflectivity with respect to infrared rays can be used, and examples thereof include a multilayer structure material, an infrared reflecting pigment, and a liquid crystal material having a cholesteric structure. it can. The wavelength of infrared rays reflected by the infrared reflecting material is not particularly limited, but is usually 800 nm to 2500 nm.

Examples of the multilayer structure material include a multilayer structure material composed of a layer having an infrared reflection surface (infrared reflection layer) formed at intervals that reflect infrared rays. The multilayer structure material reflects infrared light having a specific wavelength by Bragg reflection of each layer (infrared reflective layer).
Specifically, the infrared reflective layer can be formed using a multilayer liquid crystal material having a fixed cholesteric structure such as a crosslinked cholesteric liquid crystal.

As the infrared reflective pigment, powder and particles of an infrared reflective material are used, and any of inorganic pigments and organic pigments can be used. Examples of inorganic pigments include composite metal oxides such as titanium oxide (TiO ₂ ), zinc oxide, zinc sulfide, lead white, antimony oxide, zirconium oxide, indium tin oxide (ITO), and antimony-doped tin oxide (ATO). , Metals such as aluminum, gold, and copper. Further, as an inorganic pigment, a transparent support material such as natural or synthetic mica, another foliar silicate, glass flake, flaky silicon dioxide or aluminum oxide described in JP-A-2004-4840, and a metal oxide An interference pigment made of a coating can also be used. On the other hand, examples of the organic pigment include pigments described in JP-A-2005-330466 and JP-A-2002-249676, and examples thereof include azo, anthraquinone, phthalocyanine, perinone / perylene, Indigo / thioindigo, dioxazine, quinacridone, isoindolinone, isoindoline, diketopyrrolopyrrole, azomethine, and azomethine azo organic dyes can be used.

  Examples of the liquid crystal material having a cholesteric structure (so-called cholesteric liquid crystal material) include a chiral nematic liquid crystal material obtained by mixing a nematic liquid crystal with a chiral agent, or a polymer cholesteric liquid crystal material.

  The content of the infrared reflecting material in the fine particles is not particularly limited as long as identification by infrared reflection is possible, and can be about 0.1% by mass to 50% by mass.

(Infrared absorbing material)
The infrared absorbing material used in the present embodiment is not particularly limited as long as it is a material that can absorb infrared rays (800 nm to 1100 nm). Among them, an infrared absorbing material that absorbs a wavelength range of 800 nm to 1100 nm and has a sufficient light transmittance in the visible light range, that is, in a wavelength range of 380 nm to 780 nm is preferable.

  Examples of infrared absorbing materials include polymethine compounds, cyanine compounds, phthalocyanine compounds, naphthalocyanine compounds, naphthoquinone compounds, anthraquinone compounds, dithiol compounds, immonium compounds, diimonium compounds, aminium compounds, Pyryllium compounds, cerium compounds, squarylium compounds, copper complexes, nickel complexes, dithiol metal complexes, benzenedithiol metal complex anions disclosed in JP 2007-163644 and cyanine dye cations Organic infrared absorbing materials such as counterion conjugates, and composite tungsten oxide, tin oxide, indium oxide, magnesium oxide, titanium oxide, chromium oxide, dioxide oxide disclosed in JP-A-2006-154516 Koniumu, nickel oxide, aluminum oxide, zinc oxide, iron oxide, ammonium, lead oxide, bismuth oxide, lanthanum oxide, tungsten oxide, and inorganic infrared absorbing material such as indium tin oxide (ITO). An infrared absorption material can be used individually or in combination of 2 or more types. The “system compound” refers to an anthraquinone derivative in the case of an anthraquinone compound, for example.

  The infrared absorbing material is preferably selected as appropriate depending on the type of resin used. For example, when a photocurable resin or a photosensitive resin is used, an inorganic near-infrared absorbing material such as composite tungsten oxide can be suitably used as the infrared absorbing material.

  The content of the infrared absorbing material in the fine particles is not particularly limited as long as it can be identified by absorption of infrared rays, but is preferably in the range of 0.1% by mass to 10% by mass. This is because if the content of the infrared absorbing material is within the above range, a sufficient infrared absorbing function can be exhibited and a sufficient amount of visible light can be transmitted.

(Quantum dot material)
Quantum dot materials are semiconductor nanometer-sized fine particles that have specific optical and electrical properties due to the quantum confinement effect (quantum size effect) in which electrons and excitons are confined in small crystals of nanometer size. It is also called a semiconductor nanoparticle or a semiconductor nanocrystal.
The quantum dot material used in the present embodiment is not particularly limited as long as it is a nanometer-sized fine particle of semiconductor and produces a quantum confinement effect (quantum size effect). For example, there are semiconductor fine particles whose emission color is regulated by their own particle size and semiconductor fine particles having a dopant.

  As the quantum dot material, for example, the quantum dots described in JP2009-99563A can be used.

  The content of the quantum dot material in the fine particles is not particularly limited as long as it can be identified by light emission, and can be about 0.1% by mass to 50% by mass.

(Magnetic material)
Magnetic materials used in this embodiment include nuclear magnetic resonance (NMR), nuclear quadrupole resonance (NQR), electron spin resonance (ESR), ferromagnetic resonance, antiferromagnetic resonance, ferrimagnetic resonance, domain wall resonance, spin Those exhibiting magnetic resonance such as wave resonance and spin echo resonance can be used.

Since the resonance frequency is determined by the gyromagnetic ratio γ, which is an intrinsic parameter of the nucleus, and the magnetic field strength of the external magnetic field, the presence of fine particles can be recognized by selecting the resonance frequency at which the magnetic material exhibits magnetic resonance. And authenticity determination can be performed.
For example, when fine particles containing a magnetic material and fine particles not containing a magnetic material are irradiated with electromagnetic waves having a frequency at which the magnetic material exhibits nuclear magnetic resonance, the fine particles containing the magnetic material undergo resonance absorption and contain the magnetic material. Since the resonance absorption does not occur in the fine particles that do not, the presence of the fine particles can be recognized by observing the resonance absorption, and the authenticity determination can be performed. Further, in the obtained NMR spectrum, the position, intensity, half-value width, shape, etc. of the signal differ depending on the structure and energy state of the substance, so that it can be identified by the type of magnetic material used.

  As the magnetic material, powder or particles of magnetic material are used. Examples of the magnetic material include fine particles exhibiting magnetic resonance described in JP-A-2005-309418.

  The content of the magnetic material in the fine particles is not particularly limited as long as it can be identified by magnetic resonance, but is preferably in the range of 1% by mass to 30% by mass, and 5% by mass to 20% by mass. % Is more preferable. This is because if the content of the magnetic material is too small, identification becomes difficult, and if the content of the magnetic material is too large, it may be difficult to form information on the surface of the fine particles.

(Coloring material)
Examples of the coloring material used in this embodiment include pigments and dyes.
The coloring material is not particularly limited as long as it can be contained in fine particles, and general pigments and dyes can be used.

  As content of the coloring material in microparticles | fine-particles, it can be set as about 0.1 mass%-50 mass%.

The method for producing fine particles is not particularly limited as long as it is a method capable of producing fine particles having information that can be identified by magnifying and observing, and a general method for producing such fine particles may be used. Can be appropriately selected according to the material of the fine particles. Examples include etching, embossing, imprinting, engraving, laser writing, laser interference, masking, photolithography and the like. In the case of fine particles having a three-dimensional shape, direct drawing, gradation exposure using a gradation mask, cutting, laser processing, stereolithography, and the like can be given.
When forming fine particles having two or more pieces of information, these methods may be combined or the same method may be repeated.

  As the gradation mask, for example, a photomask for controlling the distribution of transmitted light amount (exposure amount) at the time of exposure according to the distribution state of a fine dot pattern that is not resolved at the exposure wavelength, or a light shielding agent is provided on the transparent substrate. A photomask (gray mask) dispersed in a density pattern can be used. JP, 2004-296590, A can be referred to for a photomask of a dot pattern. For gray masks, reference can be made to JP-A-2002-6473.

(C) Substrate The substrate used in the present embodiment is not particularly limited as long as the fine particles can be dispersed and a transparent resin composition described later can be disposed. In this embodiment, it is preferable to select appropriately according to whether or not the substrate peeling step described later is performed and the formation position of the substrate.

  In this embodiment, when performing a base material peeling process, it does not specifically limit as a base material. Moreover, the base material may or may not have optical transparency. As such a base material, a glass base material, a resin base material, etc. can be used, for example.

  Further, in this embodiment, the substrate peeling step is not performed, and when the fine particle-containing sheet is used for an article, the substrate is disposed so as to be on the back side of the fine particle-containing layer and the hologram layer. In some cases, the substrate may or may not have optical transparency.

On the other hand, in this embodiment, when the base material peeling step is not performed, and when the fine particle-containing sheet is used for an article, the base material is disposed on the surface side of the fine particle-containing layer or When the base material is arranged so as to be on the surface side of the hologram layer, the base material has light transparency and is preferably a transparent base material.
The light transmittance of the transparent substrate is not particularly limited as long as the fine particles in the fine particle-containing layer can be observed, but the total light transmittance in the visible region is preferably 10% or more.

  Moreover, when not performing a base material peeling process, it is preferable that a base material has flexibility. This is because the fine particle-containing sheet produced according to this embodiment can be applied to various forms of anti-counterfeit media.

  When not performing a base material peeling process, a general resin base material can be used as a base material. Examples thereof include resin base materials such as polyethylene terephthalate, polyvinyl chloride, polycarbonate, polypropylene, polyethylene, polystyrene, polyarylate, triacetyl cellulose, diacetyl cellulose, polymethyl methacrylate, polyimide, and polyamide.

Moreover, when not performing a base-material peeling process, it is preferable that the surface of a base material is subjected to the easy-adhesion process in order to improve adhesiveness with a fine particle content layer. The easy adhesion treatment is not particularly limited as long as the fine particle-containing layer and the substrate can be adhered to each other. For example, physical treatment such as plasma treatment, corona discharge treatment, glow discharge treatment, flame treatment, or chromium treatment A chemical treatment using an acid, a silane coupling agent, a primer agent, or the like can be given.
Among these, chemical treatment using a primer agent is preferable. In any case, the primer agent is suitable for treatment at the time of production of the substrate and for treatment of the surface of the substrate after production. A commercially available substrate can be used as the substrate treated with the primer agent. Moreover, as a primer agent which processes the base-material surface after manufacture, what is closely_contact | adhered to a resin composition should just be sufficient.

  It is preferable that the thickness of the substrate is appropriately selected depending on whether or not the substrate peeling step is performed. When performing a base material peeling process, as thickness of a base material, if it is the thickness which can support microparticles | fine-particles and a resin composition, it will not specifically limit. On the other hand, when not performing a base material peeling process, the thickness of a base material is suitably selected according to the use, kind, etc. of the fine particle content sheet manufactured by this embodiment, but it shall be about 1 micrometer-800 micrometers. Preferably, in the range of 10 μm to 50 μm.

  The substrate may be a single wafer or may be long.

A spacer may be formed on the base material. The spacer defines a region where the fine particles are dispersed and a region where the transparent resin composition is disposed, and is provided to facilitate the formation of the fine particle-containing layer. Further, the uniformity of the film thickness of the fine particle-containing layer can be maintained by the spacer.
As with the base material, the spacer may or may not be peeled off after the fine particle-containing layer forming step.
As a material for the spacer, a resin is usually used.
Examples of the method for forming the spacer include a method of attaching a resin film, an ink jet method, a printing method, and a photolithography method.

(2) Transparent resin composition arrangement | positioning process The transparent resin composition arrangement | positioning process in this embodiment is a process of arrange | positioning a transparent resin composition on the said base material with which the said microparticles | fine-particles were spread | dispersed.
Hereinafter, the arrangement method of the transparent resin composition and the transparent resin composition will be described.

(A) Arrangement method of transparent resin composition As an arrangement method of the transparent resin composition in the present embodiment, the transparent resin composition is arranged on the base material while maintaining the dispersed state of the fine particles dispersed on the base material. The method is not particularly limited as long as it can be used, and examples thereof include a method of injecting a transparent resin composition, a method of discharging the transparent resin composition by a discharge method such as a dispenser method and an ink jet method. Specifically, it is preferable to discharge a necessary amount of the transparent resin composition from a dispenser nozzle using a dispenser, and to cure this in a solidification step described later.

The thickness of the film made of the transparent resin composition disposed on the substrate is particularly limited as long as the authenticity can be determined by the fine particles when the fine particle-containing sheet produced according to the present embodiment is used as an anti-counterfeit medium. However, it is appropriately selected depending on whether or not to perform the substrate peeling step, the type of the transparent resin composition, and the like. For example, when the substrate peeling process is not performed, the thickness of the film may be relatively thin. On the other hand, when performing a base material peeling process, it is preferable that the thickness of the said film | membrane is comparatively thick from a self-supporting viewpoint. When the transparent resin composition is a curable resin composition, it is preferable that the thickness of the film is relatively thin from the viewpoint of suppressing cracking of the obtained fine particle-containing layer.
Specifically, the thickness of the film can be about 1 μm to 800 μm, and is preferably in the range of 10 μm to 50 μm.

  After disposing the transparent resin composition on the substrate, the transparent resin composition may be covered with a flat substrate in order to flatten the surface of the film made of the transparent resin composition. When the viscosity of the transparent resin composition is high, it is preferable to cover the transparent resin composition with a flat substrate. In addition, when the viscosity of a transparent resin composition is low, even if it does not cover a transparent resin composition with a flat substrate, it can planarize.

Similar to the base material, the flat substrate may or may not be peeled after the fine particle-containing layer forming step.
The flat substrate is not particularly limited as long as it has smoothness, but it is preferably selected as appropriate depending on whether or not the flat substrate is peeled off.

  When the flat substrate is peeled off, the flat substrate is not particularly limited. In addition, the flat substrate may or may not have light transmittance, but when the transparent resin composition is a photocurable resin composition, light may be irradiated from the flat substrate side. For this reason, it is preferable to have light transmittance. The light transmittance of the flat substrate can be the same as the light transmittance of the base material. As such a flat substrate, for example, a glass substrate, a resin substrate or the like can be used, and a cover glass is preferably used.

On the other hand, when the flat substrate is not peeled off, the flat substrate preferably has light transmittance. As described above, the light transmittance of the flat substrate can be the same as the light transmittance of the base material.
In the case where the flat substrate is not peeled off, the flat substrate preferably has flexibility. This is because the fine particle-containing sheet produced according to this embodiment can be applied to various forms of anti-counterfeit media.
As such a flat substrate, the resin base material used for the said base material can be used.

(B) Transparent resin composition The light transmittance of the transparent resin composition used in the present embodiment is not particularly limited as long as the fine particles in the obtained fine particle-containing layer can be observed. When the film is formed with the same thickness as the containing layer, the total light transmittance in the visible region is preferably 10% or more, more preferably 50% or more, and particularly preferably 80% or more.
In addition, the said total light transmittance is the value measured based on JISK7105.

The transparent resin composition is not particularly limited as long as it satisfies the above light transmittance. For example, any of a photocurable resin composition, a thermosetting resin composition, and a thermoplastic resin composition is used. be able to.
Especially, curable resin compositions, such as a photocurable resin composition and a thermosetting resin composition, are preferable. This is because the viscosity of the curable resin composition is relatively easy to adjust and the viscosity can be lowered. When the viscosity of the transparent resin composition is low, it becomes easy to dispose the transparent resin composition on the base material while maintaining the dispersed state of the fine particles dispersed on the base material.
In particular, a photocurable resin composition is preferable. By using a photocurable resin composition, it becomes possible to also use a base material with low heat resistance, and the choice of the use of the fine particle containing sheet manufactured by this embodiment spreads. Moreover, it is because production efficiency can be improved.
Specifically, any transparent resin composition such as a modified acrylate acrylic resin composition, a urethane resin composition, or an epoxy resin composition can be used.

  Moreover, the transparent resin composition may contain functional materials such as an ultraviolet light emitting material, an infrared light emitting material, an infrared reflecting material, an infrared absorbing material, and a quantum dot material.

  For example, when the transparent resin composition contains an ultraviolet light emitting material or an infrared light emitting material and the fine particles do not contain an ultraviolet light emitting material or an infrared light emitting material, the position of the fine particles is specified by the presence or absence of light emission. This makes it possible to easily determine the authenticity and improve the forgery prevention effect. Further, when the transparent resin composition contains an ultraviolet light emitting material or an infrared light emitting material, and the fine particles also contain an ultraviolet light emitting material or an infrared light emitting material, the position of the fine particles should be specified by the wavelength of light emission. This makes it possible to easily determine the authenticity and improve the forgery prevention effect.

  When the transparent resin composition contains an infrared reflecting material or an infrared absorbing material and the fine particles do not contain an infrared reflecting material or an infrared absorbing material, the position of the fine particles is determined by the presence or absence of infrared absorption or reflection. This makes it possible to easily determine the authenticity and improve the anti-counterfeit effect. Further, when the transparent resin composition contains an infrared reflecting material or an infrared absorbing material, and the fine particles also contain an infrared reflecting material or an infrared absorbing material, the position of the fine particles depends on the wavelength of infrared rays to be absorbed or reflected. This makes it possible to determine the authenticity and to improve the effect of preventing forgery.

  In the case where the transparent resin composition contains a quantum dot material and the fine particles do not contain a quantum dot material, the position of the fine particles can be specified by the presence or absence of light emission, and authenticity determination becomes easy. It becomes possible to improve the anti-counterfeit effect. In addition, when the anti-counterfeit ink contains a quantum dot material, and the fine particles also contain a quantum dot material, the position of the fine particles can be specified by the wavelength of light emission, and authenticity determination is easy. In addition, it is possible to improve the forgery prevention effect.

  The functional material is the same as that described in the above section “1. Fine particle spraying step (2) Fine particles”, and the description thereof is omitted here.

  The content of the ultraviolet light emitting material in the transparent resin composition is not particularly limited as long as it can be identified by light emission, and can be about 1% by mass to 50% by mass.

  The content of the infrared light emitting material in the transparent resin composition is not particularly limited as long as it can be identified by light emission, and can be about 1% by mass to 50% by mass.

  The content of the infrared reflecting material in the transparent resin composition is not particularly limited as long as it can be identified by infrared reflection, and can be about 0.1% by mass to 50% by mass.

  The content of the infrared absorbing material in the transparent resin composition is not particularly limited as long as it can be identified by absorption of infrared rays, but is preferably in the range of 0.1% by mass to 10% by mass. . This is because if the content of the infrared absorbing material is within the above range, a sufficient infrared absorbing function can be exhibited and a sufficient amount of visible light can be transmitted.

  The content of the quantum dot material in the transparent resin composition is not particularly limited as long as it can be identified by light emission, and can be about 0.1% by mass to 50% by mass.

  The transparent resin composition may contain a solvent. The solvent is not particularly limited as long as the fine particles are dispersed and not dissolved. Moreover, a solvent may be used individually by 1 type and may be used in mixture of 2 or more types.

(3) Solidification process The solidification process in this embodiment is a process of solidifying the transparent resin composition.
The method for solidifying the transparent resin composition is appropriately selected according to the type of the transparent resin composition. In the case of the curable resin composition, a curing method using light or heat is used. In the case of a thermoplastic resin composition, a cooling method is used.
When the transparent resin composition is covered with a flat substrate, the transparent resin composition is solidified in a state where the transparent resin composition is covered with the flat substrate, thereby forming a fine particle-containing layer with good smoothness. Can be obtained.

(4) Fine particle-containing layer In this embodiment, the content of the fine particles in the fine particle-containing layer can be determined by authenticity when the fine particle-containing sheet produced according to this embodiment is used as an anti-counterfeit medium. Although there is no particular limitation as long as it is present, it is preferable that at least one fine particle is contained per 1 cm ^{2 of} the fine particle-containing layer.

In addition, the fine particle-containing layer may be formed on one surface or in a pattern on the substrate. When the pattern shape of the fine particle-containing layer is a shape that represents a predetermined meaning, the fine particles can be used as hidden information, and the effect of preventing forgery can be enhanced.
When the fine particle-containing layer is formed in a pattern on the substrate, a spacer may be formed on the substrate, and the pattern shape of the fine particle-containing layer may be defined by the spacer, and the fine particle-containing layer may be formed after the formation of the fine particle-containing layer. You may punch only.

The film thickness of the fine particle-containing layer is not particularly limited as long as the fine particle-containing sheet produced according to the present embodiment is used as a forgery prevention medium, as long as the authenticity can be determined by the fine particles. Similarly to the thickness of the film made of the composition, it is appropriately selected depending on whether or not to perform the substrate peeling step, the type of transparent resin composition to be used, and the like.
Specifically, the film thickness of the fine particle-containing layer can be about 0.1 μm to 500 μm, and is preferably in the range of 1 μm to 100 μm.

2. Substrate peeling step In this embodiment, a substrate peeling step for peeling the substrate may be performed after the fine particle-containing layer forming step. The fine particle-containing layer can be easily laminated with other layers, and a high value-added fine particle-containing sheet can be obtained. Moreover, it is possible to reduce the thickness of the fine particle-containing sheet by peeling the substrate.

  When the spacer is formed on the base material, the spacer may be peeled when the base material is peeled off. Further, when a flat substrate is disposed on the fine particle-containing layer, the flat substrate may be peeled when the base material is peeled off.

  On the other hand, in this embodiment, it is not necessary to perform a base material peeling process. When the substrate peeling step is not performed, the strength of the fine particle-containing sheet produced according to this embodiment can be increased, and the handleability of the fine particle-containing sheet is improved. In particular, when the transparent resin composition is a curable resin composition, it is preferable that the fine particle-containing layer is relatively thin from the viewpoint of suppressing cracking of the fine particle-containing layer, so that the substrate peeling step is not performed. preferable. In addition, when the fine particle-containing sheet produced according to the present embodiment is applied to the anti-counterfeit medium, the fine particle-containing layer is formed by the base material when the substrate is disposed on the surface side of the fine particle-containing layer. Can also be protected.

3. Other Steps In this embodiment, in addition to the fine particle-containing layer forming step and the substrate peeling step, an optional step may be included.

(1) Adhesive Layer / Peeling Substrate Laminating Step In this embodiment, the adhesive layer 24 is formed on the fine particle-containing layer 5 as illustrated in FIGS. 7 and 8 after the fine particle-containing layer forming step. You may perform the adhesion layer and peeling base material lamination process which laminates | peel the peeling base material 23 through the adhesion layer 24. FIG. This is because, when the fine particle-containing sheet produced according to this embodiment is applied to the anti-counterfeit medium, the release substrate can be peeled off, and the fine particle-containing sheet can be easily attached via the adhesive layer. Moreover, it is because handling of a fine particle containing sheet | seat becomes easy because the peeling base material is laminated | stacked on the adhesion layer.

  The adhesive layer / peeling substrate lamination step may be performed after the fine particle-containing layer forming step. When performing the said base material peeling process, an adhesion layer and peeling base material lamination process may be performed before a base material peeling process, and may be performed after a base material peeling process.

  When the base material peeling step is not performed, the adhesive layer and the release base material may be laminated on the base material side or may be laminated on the fine particle-containing layer side. As will be described later, when a hard coat layer forming step of forming a hard coat layer on the fine particle-containing layer is performed, an adhesive layer and a release substrate are laminated on the surface opposite to the hard coat layer. In addition, as will be described later, when performing a hologram layer forming step of laminating the fine particle-containing layer and the hologram layer, the adhesive layer and the release substrate are laminated on the hologram layer side.

  The material of the adhesive layer is not particularly limited as long as the fine particle-containing sheet produced according to the present embodiment can be attached via the adhesive layer. For example, thermoplastic, thermosetting, photocuring, Any of the elastomers can be used, and is appropriately selected according to the use and type of the fine particle-containing sheet. When the fine particle-containing sheet is used as a transfer foil, an adhesive layer having heat sealability is used.

The film thickness of the pressure-sensitive adhesive layer is not particularly limited as long as the fine particle-containing sheet produced according to this embodiment can be attached via the pressure-sensitive adhesive layer, and can be, for example, about 1 μm to 100 μm.
A known method can be used as a method for forming the adhesive layer.

  The peeling substrate is peeled off when the fine particle-containing sheet produced according to this embodiment is applied to a forgery prevention medium. As a peeling base material, if it has peelability, it will not specifically limit, For example, a general resin base material can be used.

(2) Hard Coat Layer Forming Step In this embodiment, after the fine particle containing layer forming step, a hard coat layer forming step for forming a hard coat layer 26 on the fine particle containing layer 5 is performed as illustrated in FIG. May be. This is because the fine particle-containing layer can be protected by the hard coat layer.

The hard coat layer forming step may be performed after the fine particle-containing layer forming step. When performing the said base material peeling process, although a hard-coat layer formation process may be performed before a base material peeling process and may be performed after a base material peeling process, it is normally performed before a base material peeling process. . Moreover, when performing the said adhesion layer and peeling base material lamination process, a hard-coat layer formation process may be performed before an adhesion layer and peeling base material lamination process, and may be performed after an adhesion layer and peeling base material lamination process Good.
The hard coat layer is formed on the fine particle-containing layer so that when the fine particle-containing sheet produced according to this embodiment is applied to the anti-counterfeit medium, the hard coat layer is on the surface side of the fine particle-containing layer.

  The hard coat layer is light transmissive. The light transmittance of the hard coat layer is not particularly limited as long as the fine particles in the fine particle-containing layer can be observed, but the total light transmittance in the visible region is preferably 10% or more, and more preferably 50% or more. It is preferable that it is 80% or more especially.

  The material of the hard coat layer is not particularly limited as long as it satisfies the above light transmittance and can protect the fine particle-containing layer. For example, a photocurable resin can be used.

The film thickness of the hard coat layer is not particularly limited as long as the fine particle-containing layer can be protected, and can be, for example, about 1 μm to 100 μm.
As a method for forming the hard coat layer, a known method can be used.

(3) Hologram layer forming step In this embodiment, a hologram layer forming step of laminating the fine particle-containing layer 5 and the hologram layer 27 may be performed as illustrated in FIGS. 10 and 11. This is because the hologram layer can enhance the forgery prevention effect. In addition, the hologram layer can be protected by the fine particle-containing layer.

  The hologram layer forming step may be performed before forming the fine particle-containing layer, and the fine particle-containing layer may be formed on the hologram layer, or may be performed after the fine particle-containing layer forming step, and the hologram layer may be laminated on the fine particle-containing layer. Good. When performing the said base material peeling process, a hologram layer formation process may be performed before a base material peeling process, and may be performed after a base material peeling process. When performing the said adhesion layer and peeling base material lamination process, a hologram layer formation process is normally performed before an adhesion layer and peeling base material lamination process.

The hologram layer may be laminated on the substrate side or the fine particle-containing layer side when the substrate peeling step is not performed. When performing the hard coat layer forming step, a hologram layer is laminated on the surface opposite to the hard coat layer. When performing the adhesion layer / peeling substrate lamination step, the particle-containing layer and the hologram layer are laminated so that the hologram layer is disposed between the particle-containing layer and the adhesion layer.
The hologram layer is laminated with the fine particle-containing layer so that when the fine particle-containing sheet produced according to this embodiment is applied to the anti-counterfeit medium, the hologram layer is on the back side of the fine particle-containing layer.

The type of the hologram layer is not particularly limited, and may be a relief hologram layer or a volume hologram layer. The relief hologram layer is excellent in productivity, while the volume hologram layer is excellent in the forgery prevention effect.
A known hologram layer can be used.

  As a method for laminating the fine particle-containing layer and the hologram layer, for example, the fine particle-containing layer may be formed on the hologram layer formed on the substrate, and the fine particle-containing layer and the hologram layer are laminated via an adhesive layer. Alternatively, the fine particle-containing layer and the hologram layer may be laminated by thermocompression bonding.

4). Fine particle-containing sheet The fine particle-containing sheet produced according to this embodiment may be a single sheet or a long sheet.

  Further, the shape of the fine particle-containing sheet produced according to this embodiment is not particularly limited, and may be a rectangular shape, a polygonal shape, a circular shape, an elliptical shape, or any other shape. When the shape of the fine particle-containing sheet produced according to this embodiment is a shape that represents a predetermined meaning, the fine particles can be used as hidden information.

In this embodiment, as a method for inspecting the fine particle-containing sheet, for example, as shown in FIG. 12, a method of irradiating the fine particle-containing sheet 1 with LED illumination 51 and acquiring an image with a camera (line sensor) 52 is given. be able to. In FIG. 12, the LED illumination 51 is arranged on the side opposite to the camera 52 with respect to the fine particle-containing sheet 1 to observe the transmitted light. Although not shown, the fine particle-containing sheet is on the same side as the camera. LED illumination may be arranged to observe the reflected light.
In the inspection apparatus for the fine particle-containing sheet, the position of the fine particle is mapped, stored in a database, and collation is possible.

  In the inspection, if there is a region that does not contain fine particles in the fine particle-containing layer, a laser marking device is used to mark the region that does not contain fine particles, and the fine particle-containing sheet is formed into a predetermined shape. May be excluded.

The fine particle-containing sheet produced according to this embodiment can be used as a label as it is or as a transfer foil.
When the fine particle-containing sheet has a hologram layer, it can be used as a hologram label or a hologram transfer foil. The fine particle-containing sheet can also be used as a laminate film on an anti-counterfeit medium.

  When the fine particle-containing sheet produced according to this embodiment is applied to an anti-counterfeit medium, the fine particle-containing sheet may be fixed to the surface of the anti-counterfeit medium. In addition, the fine particle-containing sheet may be embedded in the anti-counterfeit medium, and when the anti-counterfeit medium is made of paper, the fine particle-containing sheet may be cut into thin pieces and formed on paper. When the fine particle-containing sheet is fixed to the surface of the anti-counterfeit medium, the fine particle-containing sheet may be attached as it is or may be transferred. An example of the transfer method is a thermal transfer method.

Since the fine particle-containing sheet itself can be light-transmitting, it can be applied to various anti-counterfeit media.
The fine particle-containing sheet is suitable for anti-counterfeiting applications, such as gold vouchers, gift cards, credit cards, ID cards, passports, driver's licenses, brand products, automobile parts, precision equipment parts, home appliances, cosmetics, pharmaceuticals, foods, It can be used for OA supplies, sporting goods, CDs, DVDs, software, tobacco, liquor, etc.

  FIGS. 13A and 13B are schematic views showing an example of an anti-counterfeit medium to which the fine particle-containing sheet is applied. FIG. 13A is a top view, and FIG. 13B is a diagram in FIG. It is DD sectional view taken on the line. In the anti-counterfeit medium 60 shown in FIGS. 13A and 13B, the fine particle-containing sheet 1 is fixed to the surface of the support 61.

  14A to 14C are schematic views showing other examples of the anti-counterfeit medium to which the fine particle-containing sheet is applied. FIG. 14A is a top view, and FIG. 14B is FIG. ) Is a cross-sectional view taken along the line E-E, and FIG. 14C is a perspective view showing a laminated structure of the anti-counterfeit medium. In the anti-counterfeit medium 60 shown in FIGS. 14A to 14C, the first resin layer 62, the fine particle-containing sheet 1 and the second resin layer 63 are laminated on the support 61, and the anti-counterfeit medium The fine particle-containing sheet 1 is embedded inside 60. When the fine particle-containing sheet is embedded in the anti-counterfeit medium, the fine particle-containing sheet can be prevented from being peeled off and misused.

  The anti-counterfeit medium to which the fine particle-containing sheet is applied has an excellent anti-counterfeit effect, and it is possible to easily determine the authenticity using only a simple instrument such as a loupe.

  The support constituting the anti-counterfeit medium is appropriately selected according to the use of the anti-counterfeit medium. The support may or may not have optical transparency. Examples of the material for the support include glass, resin, metal, paper, and the like.

Moreover, the 1st resin layer which comprises a forgery prevention medium may have light transmittance, and does not need to have it. In particular, when a functional layer (for example, an image receiving layer or a hologram layer) capable of recording or having arbitrary information is formed between the support and the first resin layer, the first resin layer transmits light. It is preferable to have properties. When the first resin layer has light transmittance, the light transmittance can be the same as the light transmittance when the substrate constituting the fine particle-containing sheet is a transparent substrate. As the first resin layer, for example, a general resin substrate can be used.
On the other hand, the second resin layer is light transmissive. The light transmittance of the second resin layer can be the same as the light transmittance when the substrate constituting the fine particle-containing sheet is a transparent substrate. As the second resin layer, for example, a general resin substrate can be used.
Examples of the method of laminating the support, the first resin layer, the fine particle-containing sheet, and the second resin layer include a method of laminating each layer through an adhesive layer, a method of laminating each layer by thermocompression bonding, and the like. .

II. Second Embodiment The method for producing a fine particle-containing sheet according to the present embodiment includes a fine particle-containing layer forming step of forming a fine particle-containing layer in which fine particles having information that can be identified by magnifying and observing are dispersed in a transparent resin. A method for producing a fine particle-containing sheet, wherein the fine particle-containing layer forming step includes a transparent resin composition arranging step of arranging a transparent resin composition on a substrate, and the group in which the transparent resin composition is arranged. It includes a fine particle spraying step of spraying the fine particles on a material and a solidification step of solidifying the transparent resin composition.

A method for producing the fine particle-containing sheet of the present embodiment will be described with reference to the drawings.
FIGS. 15A to 15F are process diagrams showing an example of the method for producing the fine particle-containing sheet of the present embodiment. First, as shown to Fig.15 (a), the transparent resin composition 4a is inject | poured on the base material 2 in which the spacer 11 was formed (transparent resin composition arrangement | positioning process). Next, as shown in FIG. 15 (b), predetermined fine particles 3 are spread on the base material 2 on which the transparent resin composition 4 a is disposed (fine particle spraying step). Subsequently, as shown in FIG. 15C, the transparent resin composition 4a is covered with a flat substrate 12 such as a cover glass and planarized. Next, in this state, the transparent resin composition 4a is solidified (solidification step). As a result, as shown in FIG. 15D, the fine particle-containing layer 5 in which the fine particles 3 are dispersed in the transparent resin 4b is obtained (fine particle-containing layer forming step). Next, as shown in FIG. 15 (e), the flat substrate 12 and the spacer 11 are peeled from the fine particle-containing layer 5, and further, as shown in FIG. 15 (f), the fine particle-containing layer 5 is peeled from the base material 2. (Substrate peeling step). In this way, the fine particle-containing sheet 1 can be obtained.

  In the fine particle-containing sheet produced according to the present embodiment, the fine particle-containing sheet itself can be inspected in advance before being used for an article, so there is no need to inspect each article, and the advantage that the inspection is easy is provided. Have.

In addition, in the fine particle-containing sheet produced according to this embodiment, as described above, the fine particle-containing sheet itself can be inspected in advance before being used in the article, so that the fine particles are reliably used in the article. It can be guaranteed. In addition, when a conventional ink containing fine particles is used to form a fine particle-containing layer by applying ink containing fine particles and a transparent resin composition on a substrate, the content of the fine particles in the fine particle-containing layer is grasped. In particular, when the content of fine particles in the ink is small and the amount of ink used is small, it is difficult to ensure that the fine particle-containing layer surely contains fine particles. On the other hand, according to this embodiment, since the fine resin particles are dispersed after disposing the transparent resin composition on the base material, the content of the fine particles in the fine particle-containing layer can be easily grasped. It becomes possible to reliably contain fine particles in the layer. Therefore, it is possible to reliably achieve the forgery preventing effect.
Furthermore, in the fine particle-containing sheet produced according to the present embodiment, it is possible to perform mapping on the number and position of the fine particles in the fine particle-containing sheet, and use the article in a state where the number and position of the fine particles are determined in advance. Therefore, advanced anti-counterfeiting can be realized.

  Moreover, unlike the ink and toner containing fine particles, the fine particle-containing sheet produced according to this embodiment has an advantage that it can be easily fixed to an article and has excellent handleability. Furthermore, the fine particle-containing sheet produced according to this embodiment can be easily laminated with other sheets, and a high-value-added fine particle-containing sheet can be obtained.

  In addition, since it is the same as that of what was described in the said 1st embodiment about a base material peeling process, another process, and a fine particle containing sheet | seat, description here is abbreviate | omitted. Hereinafter, the fine particle-containing layer forming step in the method for producing the fine particle-containing sheet of the present embodiment will be described.

1. Fine particle-containing layer forming step The fine particle-containing layer forming step in this embodiment is a step of forming a fine particle-containing layer in which fine particles having information that can be identified by magnifying and observing are dispersed in a transparent resin. A transparent resin composition disposing step for disposing a transparent resin composition on a material, a fine particle dispersal step for dispersing the fine particles on the substrate on which the transparent resin composition is disposed, and the transparent resin composition. A solidifying step for solidifying.
In addition, since it is the same as that of what was described in the said 1st embodiment about a solidification process and a fine particle content layer, description here is abbreviate | omitted. Hereinafter, other steps in the fine particle-containing layer forming step will be described.

(1) Transparent resin composition arrangement | positioning process The transparent resin composition arrangement | positioning process in this embodiment is a process of arrange | positioning a transparent resin composition on a base material.
The transparent resin composition and the base material are the same as those described in the first embodiment, and thus the description thereof is omitted here. Hereinafter, the arrangement | positioning method of a transparent resin composition is demonstrated.

  The arrangement method of the transparent resin composition in the present embodiment is not particularly limited as long as the transparent resin composition can be arranged on the substrate. For example, the method of injecting the transparent resin composition, the transparent resin Examples thereof include a method of applying the composition, a method of discharging the transparent resin composition by a discharging method such as a dispenser method and an ink jet method. Specifically, it is preferable to discharge a necessary amount of the transparent resin composition from the dispenser nozzle using a dispenser and cure it in the solidification step.

  The thickness of the film made of the transparent resin composition disposed on the substrate can be the same as that described in the first embodiment.

(2) Fine particle spraying step The fine particle spraying step in this embodiment is a step of spraying fine particles having information that can be identified by magnifying and observing on the base material on which the transparent resin composition is arranged. .
The fine particles are the same as those described in the first embodiment, and the description thereof is omitted here. Hereinafter, a method for dispersing fine particles will be described.

The fine particle spraying method in the present embodiment is not particularly limited as long as it is a method capable of uniformly spraying predetermined fine particles on the substrate on which the transparent resin composition is disposed. Any of the wet spraying methods can be used.
Note that the dry spray method and the wet spray method can be the same as those described in the first embodiment, and a description thereof will be omitted.

  The amount of fine particles dispersed on the substrate can be the same as that described in the first embodiment.

After the fine particles are dispersed on the base material, the transparent resin composition may be covered with a flat substrate in order to flatten the surface of the film made of the transparent resin composition. When the viscosity of the transparent resin composition is high, it is preferable to cover the transparent resin composition with a flat substrate. In addition, when the viscosity of a transparent resin composition is low, even if it does not cover a transparent resin composition with a flat substrate, it can planarize.
Since the flat substrate can be the same as that described in the first embodiment, description thereof is omitted here.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has any configuration that has substantially the same configuration as the technical idea described in the claims of the present invention and that exhibits the same effects. Are included in the technical scope.

Hereinafter, the present invention will be specifically described with reference to examples.
[Example 1]
First, a spacer (PET / Lumirror 50T60 manufactured by Toray Industries, Inc., thickness 50 μm) is placed on the base material (Easy Adhesive PET / Toyobo Co., Ltd. A4300, thickness 38 μm), and within the area surrounded by the spacers Then, star-shaped fine particles having a particle diameter of 100 μm were spread on the substrate as they were. Subsequently, a UV curable resin composition having the following composition was injected onto the substrate on which the fine particles were dispersed.
<Composition of UV curable resin composition>
・ Polyester acrylate (Aronix M-7100: manufactured by Toagosei Co., Ltd.)
30% by mass
-Triprene glycol diacrylate (Aronix M-220: manufactured by Toagosei Co., Ltd.)
35% by mass
Trimethylolpropane triacrylate (Aronix M-309: manufactured by Toagosei Co., Ltd.) 30% by mass
1-hydroxycyclohexyl phenyl ketone (Irg184: manufactured by Ciba Specialty Chemicals) 5% by mass
White plate glass (manufactured by Corning, model number 7059, thickness 1.1 mmt) was placed as a cover glass on the injected UV curable resin composition, and was planarized. In this state, ultraviolet rays were irradiated at 30 mJ / cm ² to half-cure the UV curable resin composition, and then the cover glass and the spacer were peeled off. Furthermore, ultraviolet rays were irradiated at 2000 mJ / cm ² to completely harden the UV curable resin composition.
Through these steps, a fine particle-containing layer was formed on the base material to prepare a fine particle-containing sheet. Since the substrate was transparent, the substrate was used as it was as a fine particle-containing sheet without peeling off.

[Example 2]
A card was produced using the fine particle-containing sheet produced in Example 1.
First, on a base material (PET-G / polycarbonate alloy resin, G7260 manufactured by Sumitomo Bakelite Co., Ltd., thickness 610 μm), a laser coloring layer (PET-G / polycarbonate alloy resin, PG-CLE-HL manufactured by Mitsubishi Plastics, Inc.) Thickness 50 μm), first resin layer (PA-C manufactured by Mitsubishi Plastics, thickness 50 μm), fine particle-containing sheet, and second resin layer (PA-C manufactured by Mitsubishi Plastics, thickness 50 μm) Were laminated. Each layer was joined by an adhesive layer or thermocompression bonding.
Next, laser light was irradiated from the card surface (second resin layer side) to print a print image on the laser coloring layer. At this time, the laser light passes through the second resin layer, passes through the fine particle-containing sheet in the region where the fine particle-containing sheet exists, further passes through the first resin layer, reaches the laser coloring layer, and laser coloring. Color the layer.
In this way, a card in which the fine particle-containing sheet was embedded was manufactured.

DESCRIPTION OF SYMBOLS 1 ... Fine particle containing sheet 2 ... Base material 3, 3A, 3B, 3C ... Fine particle 4a ... Transparent resin composition 4b ... Transparent resin 5 ... Fine particle content layer 11 ... Spacer 23 ... Peeling base material 24 ... Adhesive layer 26 ... Hard coat layer 27 ... Hologram layer 32, 32a, 32b ... Information that can be identified by magnifying and observing 60 ... Anti-counterfeit medium

Claims (6)

A method for producing a fine particle-containing sheet having a fine particle-containing layer forming step of forming a fine particle-containing layer in which fine particles having information identifiable by magnifying and observing are dispersed in a transparent resin,
The fine particle-containing layer forming step includes
Forming a spacer on the substrate, and placing the transparent resin composition in a region defined by the spacer;
On the base material on which the transparent resin composition is disposed, a fine particle spraying step of spraying the fine particles,
A solidification step of solidifying the transparent resin composition.   The method for producing a fine particle-containing sheet according to claim 1, wherein the surface of the base material is subjected to an easy adhesion treatment.   The method for producing a fine particle-containing sheet according to claim 1, wherein the base material is a transparent resin base material.   The method for producing a fine particle-containing sheet according to claim 1, further comprising a base material peeling step for peeling the base material after the fine particle-containing layer forming step.   The method for producing a fine particle-containing sheet according to any one of claims 1 to 4, wherein the transparent resin composition is a curable resin composition.   The transparent resin composition contains at least one selected from the group consisting of an ultraviolet light emitting material, an infrared light emitting material, an infrared reflecting material, an infrared absorbing material, and a quantum dot material. 6. The method for producing a fine particle-containing sheet according to any one of 5 to 5.

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