JP5953832B2 - Recording medium and transfer foil - Google Patents

Description

  The present invention relates to a recording medium having a high anti-counterfeit property having a magnetic recording layer, a fluorescent ink layer, and a cholesteric liquid crystal layer, and a transfer foil used in the recording medium.

  Conventionally, authenticity is determined for economically valuable high-priced products, credit cards, traveler's checks, or vouchers that generate high value when used as ID (Identification) means. A hologram (label) suitable for the above is given to prevent forgery and prove as a genuine product. However, recently, holograms that are indistinguishable from the real one are manufactured, and new ones that prove authenticity are required.

  As a medium for preventing counterfeiting, for example, Patent Document 1 proposes a magnetic card having a visual effect by hologram and a mechanical information processing capability by magnetism. Patent Document 2 proposes an authenticity identification film in which a light absorption layer, a hologram forming layer, a reflective film in which cholesteric liquid crystal alignment is fixed, and a protective layer are sequentially formed on a substrate film.

  The magnetic cards and authenticity identification films listed above have a high decorative property by hologram, and are added with specific conditions for magnetic recording or cholesteric liquid crystal alignment, and have a certain anti-counterfeiting property. The technology for counterfeiting has progressed, and at present, it is not satisfactory in terms of anti-counterfeiting.

  In order to improve anti-counterfeiting with the above-mentioned magnetic cards, etc., for example, we considered printing on the magnetic recording layer with fluorescent ink that cannot be recognized by the naked eye. Is absorbed by the magnetic recording layer, the luminance of the fluorescence is lowered, and there is a problem that the fluorescence is not sufficiently recognized. As described above, information to be displayed or recorded is increasing as a medium for preventing forgery, and further development of a recording medium corresponding to diversification of design is demanded.

JP-A-6-130882 International Publication WO2000 / 013065

  Therefore, in order to solve the above problems, the object of the present invention is to provide high anti-counterfeiting properties, and when the magnetic recording layer is printed with fluorescent ink, the fluorescent brightness is high and the recognition of fluorescence is ensured. Further, it is to provide a recording medium in which either left circularly polarized light or right circularly polarized light of incident light is reflected, and the reflected color of the cholesteric liquid crystal is changed in hue by changing the viewing angle.

The above object is achieved by the present invention described below. That is, the first of the gist of the present invention is that a black magnetic recording layer, a concealing layer made of an aluminum powder and an acrylic resin , black light irradiation on the other side surface of the transparent substrate having a cholesteric liquid crystal layer on one side. The recording medium is characterized by sequentially laminating images of fluorescent ink layers that emit fluorescence. The second of the gist of the present invention is that a black magnetic recording layer, a concealing layer made of an aluminum powder and an acrylic resin, a black light with respect to the cholesteric liquid crystal layer surface of the transparent substrate having a cholesteric liquid crystal layer on one side, A recording medium in which images of a fluorescent ink layer that develops fluorescence when irradiated are sequentially laminated.
As a result, the fluorescent ink layer on the magnetic recording layer has a high fluorescence luminance and can reliably recognize the fluorescence. Furthermore, either left circularly polarized light or right circularly polarized light of the incident light with respect to the recording medium having a cholesteric liquid crystal layer is reflected, and the reflected color of the cholesteric liquid crystal changes in hue due to a change in viewing angle. It is a highly preventive recording medium. Since the variable information and the like are recorded on the magnetic recording layer, the pattern information and the like formed on the cholesteric liquid crystal layer are included, and the fluorescent ink layer is unrecognizable with the naked eye, the anti-counterfeiting property is high. Furthermore, since it has a cholesteric liquid crystal layer on the magnetic recording layer of black, as described above, either one of left circular polarized light or right circular polarized light of the incident light is reflected, the reflection color of the cholesteric liquid crystal, This is a recording medium with high anti-counterfeiting and high design properties that exhibits selective reflectivity such that the hue changes depending on the viewing angle, and circular polarization selectivity.

In the first aspect of the present invention, a front KiToru Akirasei substrate, between the magnetic recording layer of the black, the hologram forming layer and a transparent reflective layer, and a transparent reflective layer and the magnetic recording layer sequentially arranged so as to be in contact, through the transparent substrate and the cholesteric liquid crystal layer the hologram forming layer, it Ru can be a recording medium, wherein a recognizable. In the second aspect of the present invention, the hologram forming layer and the transparent reflective layer are in contact with each other between the cholesteric liquid crystal layer and the black magnetic recording layer, and the transparent reflective layer and the black magnetic recording layer are in contact with each other. In this way, the hologram forming layer can be recognized through the transparent base material and the cholesteric liquid crystal layer.
As a result, the hologram image formed by the fine irregularities formed in the hologram forming layer becomes unique utilizing the optical characteristics of the cholesteric liquid crystal layer, and has higher anti-counterfeiting properties and higher design properties.

The third aspect of the present invention is that a cholesteric liquid crystal layer, a black magnetic recording layer, a concealing layer made of aluminum powder and an acrylic resin, and a fluorescent ink layer that develops fluorescence when irradiated with black light are formed on one surface of the substrate. The transfer foil is characterized by sequentially laminating an image and an adhesive layer.

In the third aspect of the present invention, the hologram forming layer and the transparent reflective layer are in contact with each other between the cholesteric liquid crystal layer and the black magnetic recording layer, and the transparent reflective layer and the black magnetic recording layer are in contact with each other. Can be sequentially provided.

  The recording medium of the present invention has a fluorescent ink layer on the magnetic recording layer, has a high fluorescence brightness, can reliably recognize fluorescence, and is either left circularly polarized light or right circularly polarized light of incident light. The hue of the reflected color of the cholesteric liquid crystal that reflects one side changes due to a change in viewing angle. Therefore, the magnetic recording layer on which information is recorded and the reflected color of the cholesteric liquid crystal change the hue due to the change in the viewing angle, and the cholesteric liquid crystal layer that can recognize pattern information etc. It is a recording medium with a fluorescent ink layer that can recognize information that cannot be recognized by irradiating it with black light, and has high anti-counterfeiting properties.

It is the schematic which shows one Embodiment of the recording medium of this invention. It is the schematic which shows other embodiment of the recording medium of this invention. It is the schematic which shows other embodiment of the recording medium of this invention. It is the schematic which shows other embodiment of the recording medium of this invention. It is the schematic which shows embodiment of the transfer foil of this invention, and the recording medium formed by carrying out thermal transfer using the transfer foil. It is the schematic which shows embodiment of the transfer foil of this invention, and the recording medium formed by carrying out thermal transfer using the transfer foil.

Next, an embodiment of the invention will be described in detail.
FIG. 1 shows an embodiment of a recording medium 1 of the present invention. As the transparent base material 2 having the cholesteric liquid crystal layer 7 on one side, in the case of FIG. 1, the magnetic recording layer 3, the concealing layer 4, and the fluorescent ink layer 5 are sequentially laminated in contact with the transparent base material 2. It is a recording medium. Although not shown, a hologram image with fine irregularities is formed on the surface of the cholesteric liquid crystal layer 7 in contact with the transparent substrate 2 so that the hologram image can be visually recognized by reflection from the magnetic recording layer 3. Can do. The hologram image can be observed with a unique hue that exhibits selective reflectivity and circular polarization selectivity with respect to incident light of the cholesteric liquid crystal, has high anti-counterfeiting properties, and high design.

  In the magnetic recording layer 3, for example, variable information such as the date of birth and address of the individual who becomes the owner of the recording medium is recorded by magnetism. A concealing layer 4 is formed in order to conceal the black color of the magnetic recording layer 3 and enhance the fluorescence coloring property of the fluorescent ink layer 5.

  Moreover, the fluorescent ink layer 5 can form a pattern or an image on the concealing layer 4 by various printing methods. Also, using a thermal transfer sheet provided with a heat transferable fluorescent ink layer on a substrate different from that of the recording medium 1, the fluorescent ink layer is thermally transferred onto the concealing layer of the recording medium in a pattern or image. Thus, for example, an image (or a face pattern) of the face of the individual who becomes the owner of the recording medium can be formed. If such a fluorescent ink layer is recorded as information associated with information recorded on a magnetic recording layer or the like, the anti-counterfeiting property is enhanced, which is more preferable.

  FIG. 2 shows another embodiment of the recording medium 1 of the present invention. A cholesteric liquid crystal layer 7 is provided on one surface of the transparent substrate 2, and a hologram forming layer 8, a transparent reflecting layer 6, a magnetic recording layer 3, a concealing layer 4, a fluorescence are formed on the other surface of the transparent substrate 2. A recording medium 1 in which ink layers 5 are sequentially laminated. The recording medium 1 shown in FIG. 2 includes a hologram forming layer 8 and a transparent reflective layer 6 between the transparent base material 2 and the magnetic recording layer 3 of the recording medium shown in FIG. The hologram recording layer 8 is sequentially provided so as to be in contact with the magnetic recording layer 3, and the hologram forming layer 8 can be recognized through the transparent substrate 2 and the cholesteric liquid crystal layer 7.

  FIG. 3 shows another embodiment of the recording medium 1 of the present invention. As the transparent base material 2 having the cholesteric liquid crystal layer 7 on one surface, in the case of FIG. 3, a recording having a structure in which the magnetic recording layer 3, the concealing layer 4, and the fluorescent ink layer 5 are sequentially laminated in contact with the cholesteric liquid crystal layer 7. It is a medium. Although not shown, it is possible to form a hologram image with fine irregularities on the surface of the cholesteric liquid crystal layer 7 in contact with the magnetic recording layer 3 and to make the hologram image visible by reflection from the magnetic recording layer 3. it can. The hologram image can be observed with a unique hue that exhibits the characteristics of selective reflection with respect to incident light of the cholesteric liquid crystal and circular polarization selectivity, and has high anti-counterfeiting properties and high design properties.

  FIG. 4 shows another embodiment of the recording medium 1 of the present invention. A recording medium 1 in which a cholesteric liquid crystal layer 7, a hologram forming layer 8, a transparent reflecting layer 6, a magnetic recording layer 3, a concealing layer 4, and a fluorescent ink layer 5 are sequentially laminated on one surface of a transparent substrate 2. The recording medium 1 shown in FIG. 4 includes a hologram forming layer 8 and a transparent reflective layer 6 between the cholesteric liquid crystal layer 7 and the magnetic recording layer 3 of the recording medium shown in FIG. The hologram forming layer 8 is sequentially provided so as to be in contact with the recording layer 3, and the hologram forming layer 8 can be recognized through the transparent substrate 2 and the cholesteric liquid crystal layer 7. The recording medium 1 shown in FIGS. 1 to 4 is a base material that is made into paper as a hologram thread having a tape-like or thread-like shape with a very narrow width of about 0.2 mm to 5 mm, or has transparency. Can be used by adhering to.

  FIG. 5 shows an embodiment of a transfer foil 11 of the present invention and a recording medium 1 formed by thermal transfer using the transfer foil. FIG. 5A shows a transfer foil 11 in which a cholesteric liquid crystal layer 7, a magnetic recording layer 3, a concealing layer 4, a fluorescent ink layer 5, and an adhesive layer 10 are sequentially laminated on one surface of a substrate 9. The transfer foil 11 has a structure in which a cholesteric liquid crystal layer 7, a magnetic recording layer 3, a concealing layer 4, a fluorescent ink layer 5, and an adhesive layer 10 are sequentially laminated on a substrate 9 as a thermally transferable layer 12. .

  The recording medium 1 shown in FIG. 5B is stacked so that the adhesive layer 10 of the transfer foil 11 and the adherend 13 in FIG. A plurality of layers in which the cholesteric liquid crystal layer 7, the magnetic recording layer 3, the hiding layer 4, the fluorescent ink layer 5, and the adhesive layer 10 are sequentially laminated are peeled off from the material 9 and provided on the adherend 13. That is, the illustrated recording medium 1 has a configuration in which an adhesive layer 10, a fluorescent ink layer 5, a concealing layer 4, a magnetic recording layer 3, and a cholesteric liquid crystal layer 7 are sequentially laminated on an adherend 13, The laminate is heat-transferred using the transfer foil shown in FIG.

  Although not shown, it is possible to form a hologram image with fine irregularities on the surface of the cholesteric liquid crystal layer 7 in contact with the magnetic recording layer 3 and to make the hologram image visible by reflection from the magnetic recording layer 3. it can. (This is the condition observed from the direction of the arrow A shown in the figure.) The hologram image can be observed with a unique hue that exhibits the selective reflectivity of the cholesteric liquid crystal with respect to the incident light and the characteristics of circularly polarized light, and has anti-counterfeiting properties. Is high and has high design properties.

  Further, when observed from the adherend 13 side of the recording medium 1 (under the conditions observed from the direction of the arrow B shown in the figure), the recording medium 1 has the concealing layer 4 that conceals the black color of the magnetic recording layer 3. The fluorescent ink layer 5 passes through the adherend 13 and can recognize fluorescence. However, the adherend 13 is light transmissive, for example, a transparent film, thin paper, or the like. In the magnetic recording layer 3, for example, variable information such as the date of birth and address of the individual who becomes the owner of the recording medium can be recorded magnetically.

  The fluorescent ink layer 5 can form a pattern or an image on the concealing layer 4 by various printing methods. The fluorescent ink layer 5 has a heat transferable fluorescent ink on a substrate different from the recording medium 1. Using a thermal transfer sheet provided with a layer, the fluorescent ink layer is thermally transferred in a pattern or image onto the concealing layer of the recording medium, for example, an image of an individual's face (or the owner of the recording medium) (or Face pattern) and the like. If such a fluorescent ink layer is recorded as information associated with information recorded on a magnetic recording layer or the like, the anti-counterfeiting property is enhanced, which is more preferable.

  FIG. 6 shows an embodiment of a transfer foil 11 of the present invention and a recording medium 1 formed by thermal transfer using the transfer foil. 6A, the cholesteric liquid crystal layer 7, the hologram forming layer 8, the transparent reflecting layer 6, the magnetic recording layer 3, the concealing layer 4, the fluorescent ink layer 5, and the adhesive layer 10 are provided on one surface of the substrate 9. The transfer foils 11 are sequentially stacked. This transfer foil 11 has a cholesteric liquid crystal layer 7, a hologram forming layer 8, a transparent reflective layer 6, a magnetic recording layer 3, a concealing layer 4, a fluorescent ink layer 5, an adhesive as a heat transferable layer 12 on a substrate 9. In this configuration, the layers 10 are sequentially stacked.

  The recording medium 1 shown in FIG. 6B is stacked so that the adhesive layer 10 and the adherend 13 of the transfer foil 11 of FIG. A plurality of layers in which the cholesteric liquid crystal layer 7, the hologram forming layer 8, the transparent reflection layer 6, the magnetic recording layer 3, the concealing layer 4, the fluorescent ink layer 5, and the adhesive layer 10 are sequentially laminated are peeled off from the material 9. It is provided on the body 13. That is, the illustrated recording medium 1 includes an adhesive layer 10, a fluorescent ink layer 5, a concealing layer 4, a magnetic recording layer 3, a transparent reflecting layer 6, a hologram forming layer 8, and a cholesteric liquid crystal layer 7 on an adherend 13. Are stacked in sequence, and the stack is thermally transferred using the transfer foil shown in FIG.

  In the recording medium 1 shown in FIG. 6B, the hologram forming layer 8 has a hologram image formed with fine irregularities, and the reflection by the transparent reflecting layer 6 and the black surface of the magnetic recording layer 3 are formed. Thus, the visibility of the hologram image is enhanced. In this case, the condition is such that the hologram image can be recognized by being reflected by the transparent reflective layer 6 as viewed from the cholesteric liquid crystal layer 7 side. (The conditions observed from the direction of the arrow A shown in the figure.) The hologram image exhibits selective reflectivity with respect to incident light and circular polarization selectivity of the cholesteric liquid crystal against the black surface of the magnetic recording layer. It can be observed with its unique hue, has high anti-counterfeiting properties and high design properties.

  Further, when observed from the adherend 13 side of the recording medium 1 (under the conditions observed from the direction of the arrow B shown in the figure), the recording medium 1 has the concealing layer 4 that conceals the black color of the magnetic recording layer 3. The fluorescent ink layer 5 passes through the adherend 13 and can recognize fluorescence. However, the adherend 13 is light transmissive, for example, a transparent film, thin paper, or the like. In the magnetic recording layer 3, for example, variable information such as the date of birth and address of the individual who becomes the owner of the recording medium can be recorded magnetically.

  The fluorescent ink layer 5 can form a pattern or an image on the concealing layer 4 by various printing methods. The fluorescent ink layer 5 has a heat transferable fluorescent ink on a substrate different from the recording medium 1. Using a thermal transfer sheet provided with a layer, the fluorescent ink layer is thermally transferred as a pattern or image onto the concealing layer of the recording medium, for example, an image of the face of the individual who becomes the owner of the recording medium (or the face Pattern) or the like. If such a fluorescent ink layer is recorded as information associated with information recorded on a magnetic recording layer or the like, it is more preferable because the anti-counterfeiting property is enhanced.

  The recording medium 1 has a unique hologram image through the magnetic recording layer 3 on which information is recorded, and the cholesteric liquid crystal layer 7 in which the color of the cholesteric liquid crystal changes its hue due to a change in viewing angle. By irradiating information that cannot be recognized only with the naked eye by irradiating black light, information by the fluorescent ink layer 5 can be recognized, and anti-counterfeiting is high.

Hereinafter, the recording medium of the present invention and each layer constituting the transfer foil will be described in detail.
(Base material)
Examples of the transparent substrate 2 having transparency in the recording medium of the present invention include synthetic resin films having transparency such as polyethylene terephthalate, polyethylene, polypropylene, and vinyl chloride. The thickness of the substrate is usually about 3 to 300 μm, and in the present invention, it is preferable to use a substrate having a thickness of about 20 to 175 μm in consideration of handling suitability and the like.

(Magnetic recording layer)
The magnetic recording layer 3 is composed of γ-Fe ₂ O ₃ , Co-coated γ-Fe ₂ O ₃ , Fe ₃ O ₄ , CrO ₂ , Fe, Fe—Cr, Fe—Co, Co—Cr, Co—Ni, and MnAl. A dispersion in which conventionally known magnetic fine particles such as Ba ferrite and Sr ferrite are dispersed in an appropriate resin or ink vehicle is formed by a conventionally known coating method such as a gravure method, a roll method, or a knife edge method. Can do. Further, the magnetic recording layer can also be formed by using a metal such as Fe, Fe-Cr, Fe-Co, Co-Cr, or an alloy thereof, or an oxide thereof, by vacuum deposition, sputtering, plating, or the like. .

  When the magnetic recording layer is formed by a coating method, the film thickness is about 1 to 100 μm, preferably about 5 to 20 μm. When the magnetic recording layer 3 is formed by vacuum deposition, sputtering, or plating, the film thickness is about 100 to 1 μm, preferably about 500 to 2000.

Examples of resins or ink vehicles in which magnetic fine particles such as γ-Fe ₂ O ₃ are dispersed include butyral resin, vinyl chloride-vinyl acetate copolymer resin, urethane resin, polyester resin, cellulose resin, acrylic resin, styrene-maleic An acid copolymer resin or the like is used, and a rubber-based resin such as nitrile rubber or a urethane elastomer is added as necessary. In addition, surfactants, silane coupling agents, plasticizers, waxes, silicone oils, carbon and other pigments can be added to the dispersion in which the magnetic fine particles are dispersed in the resin. .

(Hidden layer)
The concealing layer 4 is provided to conceal the black color of the magnetic recording layer and enhance the fluorescence coloring property of the fluorescent ink layer, and is composed mainly of a pigment and a binder. As the pigment, inorganic pigments can be used, for example, calcium carbonate, zinc oxide, aluminum oxide, titanium dioxide, silicon dioxide, aluminum hydroxide, barium sulfate, talc, kaolin, clay, calcined kaolin, etc., brass powder, aluminum Examples thereof include metal powders such as powder and copper powder. Examples of the white pigment include inorganic fillers such as silica, alumina, clay, talc, calcium carbonate, and barium sulfate, and white pigments such as titanium oxide and zinc oxide, which are preferably used. This is because a fluorescent image is conspicuous when the concealing layer is white and an image of the fluorescent ink layer is formed on the concealing layer.

  Any resin may be used as the binder resin in the concealing layer, and preferable resins include acrylic resins, cellulose resins, polyester resins, vinyl resins, polyurethane resins, polycarbonate resins, and the like. The hiding layer is composed of the above-mentioned pigment and a binder as main components, and other additives are added as necessary, and the coating amount is adjusted by a conventionally known method, i.e., gravure coating, gravure reverse coating, roll coating, etc. The thickness is about 5 to 50 μm when dried.

(Fluorescent ink layer)
In the recording medium of the present invention, the fluorescent ink layer 5 is provided on the concealing layer. The fluorescent ink layer can be formed by a printing method such as letterpress printing or gravure printing. Further, it is preferable to form a fluorescent ink layer as an arbitrary pattern or image as variable information by thermal transfer on the concealing layer by a thermal transfer sheet provided with a thermally transferable fluorescent ink layer on a substrate.

  Whether the fluorescent ink layer is formed by a printing method or a thermal transfer method, the fluorescent agent used is a commercially available fluorescent agent, for example, LC-0001 manufactured by Nippon Kayaku Co., Ltd. as a red coloring fluorescent agent. Examples of the green coloring fluorescent agent include EG-502 manufactured by Mitsui Chemicals, and the blue coloring fluorescent agent includes Ubitex OB manufactured by Ciba-Geigy Corporation. These fluorescent agents are almost colorless under visible light, but the above color development is observed when irradiated with black light (light having a wavelength of about 365 nm). These fluorescent agents can be dispersed or dissolved in a binder (vehicle) suitable for a printing method and a thermal transfer method, converted into an ink, printed, or coated to form a fluorescent ink layer. In this case, not only one type of fluorescent ink layer that emits fluorescence of one color is used, but also two or more fluorescent ink layers containing organic or inorganic fluorescent agents that emit fluorescence of different colors upon irradiation with ultraviolet rays. Can be formed. Thereby, a recording medium having higher anti-counterfeiting properties and excellent design properties can be obtained, which is preferable.

  The binder described above is as transparent as possible so that the formation of the fluorescent ink layer cannot be recognized with the naked eye. As the binder, a material having high transparency and capable of being melted at a heating temperature and fused to the concealing layer of the recording medium is used in the thermal transfer system. Specific examples include polyester resins, polystyrene resins, acrylic resins, polyurethane resins, acrylic urethane resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, polyamide resins, and silicone resins. Modified resins and mixtures of these resins can be used.

  In the case of the fluorescent ink layer formed by the thermal transfer method, the blending ratio of the fluorescent agent in the fluorescent ink layer is about 0.05 to 50% by mass, particularly about 0.1 to 20% by mass of the entire fluorescent ink. Is preferred. Further, the thickness of the fluorescent ink layer is usually 0.2 to 5 μm, preferably 0.4 to 3 μm.

  In the present invention, when the fluorescent ink layer is formed by the thermal transfer method, not only one type of fluorescent ink layer that generates fluorescence of one color is used, but also organic or inorganic that emits fluorescence of different colors with respect to ultraviolet irradiation. By attaching a fluorescent ink layer containing two or more colors containing a fluorescent agent to the image forming area on the concealing layer of the recording medium according to the image information to be printed so that the dots of each color do not overlap. By forming an image that emits a plurality of fluorescent colors and / or fluorescent colors that are a mixture of them when irradiated with ultraviolet rays, a recording medium with higher anti-counterfeiting properties and excellent design properties can be obtained. Therefore, this method is preferably performed in the present invention.

(Cholesteric liquid crystal layer)
As the cholesteric liquid crystal layer 7, it is possible to use any medium that exhibits optically selective reflectivity and circular polarization selectivity, such as a polymer film in which liquid crystal alignment is fixed, or a film in which cholesteric liquid crystal is dispersed in an appropriate resin. Although it is possible, a polymer film in which the liquid crystal alignment is fixed can be preferably used.

  Examples of the polymer film in which the liquid crystal alignment is fixed include a polymer film in which the low-molecular liquid crystal is cholesterically aligned and then the low-molecular liquid crystal is crosslinked and fixed by photoreaction or thermal reaction. . As another example, a side chain type or main chain type thermotropic polymer liquid crystal was cholesterically aligned in a liquid crystal state and then cooled to a temperature below the liquid crystal transition point to fix the alignment state. A polymer film can be mentioned. Furthermore, a polymer film prepared by fixing the alignment state by gradually removing the solvent after cholesteric alignment of the side chain type or main chain type lyotropic polymer liquid crystal in a solution can also be used.

  Examples of polymer liquid crystals that can be used for film production include side chain polymers such as polyacrylates, polymethacrylates, polysiloxanes, and polymalonates having liquid crystal forming groups in the side chains, and polyesters having liquid crystal forming groups in the main chain. , Main chain type polymers such as polyesteramide, polycarbonate, polyamide, and polyimide. If necessary, apply a cholesteric liquid crystal-containing ionizing radiation curable resin composition containing cholesteric liquid crystal in an ionizing radiation curable resin to an appropriate substrate, and form a film by irradiating the coating film with ionizing radiation. May be. It can also comprise so that the base material when apply | coated may be peeled off.

  The cholesteric liquid crystal constituting the cholesteric liquid crystal layer has a regular twist so that the alignment structure of the liquid crystal molecules draws a spiral in the film thickness direction, and the pitch P of the spiral (necessary for rotating the liquid crystal molecules by 360 °) 2) of (1) selective reflectivity that strongly reflects light in a specific wavelength band of incident light, and (2) circular polarization selectivity. Shows two optical properties.

  Since the selective reflectivity of (1) is limited to a specific wavelength range, the reflected light becomes a chromatic color with high color purity by appropriately selecting the pitch P of the cholesteric liquid crystal. Further, when the incident light is incident obliquely with respect to the normal line, the pitch P apparently decreases, so that the center wavelength λs shifts to the short wavelength side, and the bandwidth Δλ decreases. This phenomenon is called blue shift because the center wavelength λs shifts to the short wavelength side, and can be easily identified visually. For example, the reflected color of a cholesteric liquid crystal that is colored red when observed from the normal direction (0 ° incident position) is sequentially orange, yellow, green, blue-green, and blue as the viewing angle increases. Observe to change.

  The circularly polarized light selectivity of (2) above refers to the property of reflecting only circularly polarized light in a specific rotational direction and transmitting circularly polarized light having an opposite rotational direction. Of the incident light, the circularly polarized light component in the same direction as the twist direction of the alignment structure of the cholesteric liquid crystal is reflected, and the rotational direction of the reflected light is also the same direction, while the circularly polarized light component rotating in the opposite direction is transmitted. Is a unique property unique to cholesteric liquid crystals. For example, in the case of a cholesteric liquid crystal having a right twist structure, right circularly polarized light is reflected, the reflected light remains right circularly polarized light, and left circularly polarized light is transmitted. Therefore, the cholesteric liquid crystal layer is a layer that generates reflected light by reflecting only one of left circularly polarized light and right circularly polarized light in incident light.

  The cholesteric liquid crystal layer in the present invention has the above two optical properties. In the recording medium of the present invention, since the cholesteric liquid crystal layer has the black surface of the magnetic recording layer, the transmitted light to the recording medium is absorbed by the magnetic recording layer, and excessive reflection due to the transmitted light can be prevented. The reflected light is easily visible. When a hologram forming layer and a transparent reflective layer are provided between a transparent substrate having a cholesteric liquid crystal layer on one side and a magnetic recording layer, the hologram image formed on the hologram forming layer is With the black surface of the surface of the cholesteric liquid crystal, it can be observed with a unique hue that exhibits the selective reflection property with respect to the incident light of the cholesteric liquid crystal and the circular polarization selectivity property, and has high anti-counterfeiting properties and high design properties.

(Hologram forming layer)
The hologram forming layer 8 is formed on the recording medium by a known coating method such as roll coating, gravure coating, comma coating, or die coating and drying, or the hologram forming layer is thermally transferred. It can also be formed using a thermal transfer foil. The hologram forming layer can be made of a resin material that can reproduce the fine pattern of the hologram. Generally, thermoplastic resins such as polyvinyl chloride resin, acrylic resin, polystyrene, polycarbonate, etc., unsaturated polyester resins, melamine, epoxy, acrylate, etc. are used alone or in combination with the above thermoplastic resins. In addition, a thermoformable substance having a radically polymerizable unsaturated group, or a monomer having a radically polymerizable unsaturated group added thereto, and an ionizing radiation curable resin and Can be used. The film thickness of such a hologram forming layer is preferably in the range of 0.1 to 10 μm.

  The size and shape of the hologram image formed on the hologram forming layer is not particularly limited because it varies depending on the required mode. As a method for forming a hologram image, a conventionally known method, for example, an embossing method for embossing fine irregularities using an original plate provided with an irregular pattern of hologram interference fringes can be mentioned. The hologram image may be a planar hologram or a volume hologram. In the case of a planar hologram, a relief hologram is particularly preferable from the viewpoint of mass productivity and cost. In addition, Fresnel holograms, Fraunhofer holograms, lensless Fourier transform holograms, laser reproduction holograms such as image holograms, white light reproduction holograms such as rainbow holograms, color holograms utilizing these principles, computer holograms, hologram displays, multi A flex hologram, a holographic stereogram, a holographic diffraction grating, or the like can be used.

(Transparent reflective layer)
Further, by providing the transparent reflective layer 6 between the hologram forming layer and the magnetic recording layer, the visibility of the hologram image in the hologram forming layer is improved, and the cholesteric liquid crystal layer is black on the surface of the magnetic recording layer. Therefore, the transmitted light to the recording medium is absorbed by the magnetic recording layer, and excessive reflection by the transmitted light can be prevented, and the reflected light of a certain wavelength of the cholesteric liquid crystal layer can be effectively visually recognized.

The transparent reflective layer has a substantially colorless and transparent hue, and its optical refractive index may be higher or lower than the refractive index of the hologram forming layer, and is not particularly limited. For example, there are a thin film having a higher refractive index than that of the hologram forming layer and a thin film having a lower refractive index. Examples of the former include ZnS, TiO ₂ , Al ₂ O ₃ , Sb ₂ S ₃ , SiO, SnO ₂ and ITO. Examples of the latter include LiF, MgF ₂ , and AlF ₃ . Preferably, metal oxide or metal nitride is used. The transparent reflective layer can be formed on the relief surface of the hologram forming layer by a vacuum thin film method such as vapor deposition, sputtering, ion plating, and CVD so as to have a thickness of about 10 to 200 nm.

(Adherent)
The adherend 13 that is a part of the configuration of the recording medium 1 recognizes the fluorescent ink layer through the adherend by holding and laminating a fluorescent ink layer, a concealing layer, and the like that are thermally transferred from the transfer foil. A transparent film, thin paper or the like having light transmittance is used. As a transparent film, the thing similar to the transparent base material 2 demonstrated above can be used. Examples of the thin paper include glassine paper and high-quality paper. The thickness of these adherends is usually about 5 to 100 μm.

(Base material)
As the base material 9 of the transfer foil, various materials can be applied depending on the use as long as they have heat resistance, mechanical strength, mechanical strength that can withstand manufacturing, and solvent resistance. For example, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polyamide resins such as nylon 6 (registered trademark), polyolefin resins such as polyethylene, polypropylene and polymethylpentene, vinyl resins such as polyvinyl chloride, polymethyl Examples thereof include acrylic resins such as methacrylate, cellulose resins such as polycarbonate, cellophane, and cellulose acetate. Preferably, in terms of heat resistance and mechanical strength, polyethylene terephthalate is the most suitable for polyester resin films such as polyethylene terephthalate and polyethylene naphthalate. The thickness of the substrate is usually about 2.5 to 100 μm, but 4 to 70 μm is preferable in terms of transferability.

(Adhesive layer)
In the transfer foil used in the present invention, an adhesive layer 10 is provided in order to improve the adhesion between the adherend and the fluorescent ink layer, the hiding layer, and the like. The adhesive layer may be made of any conventionally known pressure-sensitive adhesive or heat-sensitive adhesive, but is more preferably formed from a thermoplastic resin having a glass transition temperature (Tg) of 40 ° C. to 80 ° C., for example, a polyester resin From resins with good thermal adhesiveness (heat sealability) such as vinyl chloride-vinyl acetate copolymer resin, acrylic resin, UV blocking resin, butyral resin, epoxy resin, polyamide resin, vinyl chloride resin, etc. It is preferable to select one having an appropriate glass transition temperature.

  By applying and drying a coating liquid to which an additive is added as necessary to the resin constituting the adhesive layer as described above, it is preferably formed to a thickness of about 0.5 to 10 μm at the time of drying. If the thickness of the adhesive layer is too small, the adhesion between the adherend and the fluorescent ink layer, the hiding layer, etc. is inferior, and the transfer foil tends to be poorly transferred. On the other hand, when the thickness is too large, the transfer sensitivity is lowered during the thermal transfer from the transfer foil, and the thermal transfer of the fluorescent ink layer, the concealing layer, etc. tends to become unstable.

Next, the present invention will be described more specifically with reference to examples. Hereinafter, unless otherwise specified, parts or% is based on mass.
Example 1
As the transparent substrate 2, a transparent hard vinyl chloride film having a thickness of 100 μm was used. On one surface of the substrate, a cholesteric liquid crystal layer 7 having a holographic image of an irregular shape of a predetermined logo mark was provided by a thermal transfer method. In addition, said hologram image is the conditions provided in the surface which contact | connects a transparent base material. Further, γ-Fe ₂ O ₃ magnetic fine particles and a magnetic recording layer 3 made of urethane resin are applied to the other surface of the transparent substrate so as to have a thickness of 15 μm (after drying). did.

  On the magnetic recording layer 3, a concealing layer 4 made of aluminum powder and acrylic resin was applied so as to cover the entire magnetic recording layer 3 so as to have a thickness of 20 μm (after drying). .

  On the magnetic recording layer 3 in the recording medium produced as described above, the date of birth and address variable information of the individual who will be the owner of the recording medium are written and recorded. Further, on the concealing layer 4 of the recording medium, a fluorescent ink layer thermally transferred with a thickness of 3 μm using a separately prepared fluorescent ink layer that can be thermally transferred is displayed as the above personal face image. The recording medium 1 of Example 1 was produced. However, the fluorescent ink layer contains a blue coloring fluorescent agent.

  In the above recording medium, the fluorescent ink layer on the magnetic recording layer has a high fluorescence luminance and can reliably recognize the fluorescence. Furthermore, either the left circularly polarized light or the right circularly polarized light of the incident light with respect to the recording medium having a cholesteric liquid crystal layer is reflected, and the reflected color of the cholesteric liquid crystal changes in hue due to a change in viewing angle. Variable information and the like are recorded on the magnetic recording layer, the pattern information and the like formed on the cholesteric liquid crystal layer are included, and the fluorescent ink layer that cannot be recognized by the naked eye has high anti-counterfeiting properties. . Further, this recording medium could be used as a hologram thread having a tape shape with a width of 2 mm.

(Example 2)
The recording medium produced in Example 1 was changed to a configuration in which the hologram forming layer 8 and the transparent reflective layer 6 were provided between the transparent substrate 2 and the magnetic recording layer 3. That is, a hologram forming layer 8 (thickness: 2.0 μm) mainly composed of a melamine-based crosslinkable ultraviolet curable resin having a hologram image having a concavo-convex shape with a predetermined logo mark, and a transparent reflecting layer 6 (thickness) on which titanium oxide is deposited. 500 mm) was provided by a thermal transfer method. The above hologram image is a condition provided on the surface in contact with the transparent reflective layer.

In addition, the recording medium of Example 2 was formed in the same manner as the recording medium of Example 1 except that the conditions for forming the fluorescent ink layer by thermal transfer formed on the concealing layer of the recording medium were changed to the following conditions. Produced. (See Figure 2)
Using a thermal transfer sheet in which a heat transferable fluorescent ink layer (thickness 3 μm) containing a blue coloring fluorescent agent and a heat transferable fluorescent ink layer (thickness 3 μm) containing a red coloring fluorescent agent are formed in a surface sequence, On the concealing layer of the recording medium, the above personal face image is formed by thermally transferring the hair and eyebrows with a fluorescent ink layer of blue coloring fluorescent agent, and other facial contours are fluorescent with red coloring fluorescent agent. A recording medium of Example 2 was produced by thermal transfer using an ink layer.

  In the recording medium, two fluorescent colors were generated, their fluorescent luminances were high, and the fluorescence was reliably recognized. Further, the visibility of the hologram image was higher than that of the recording medium of Example 1, and therefore, the anti-counterfeiting property was higher than that of the recording medium of Example 1, and the design property was excellent. Further, this recording medium could be used as a hologram thread having a tape shape with a width of 2 mm.

Example 3
A polyethylene terephthalate film having a thickness of 10 μm was used as the substrate 9, and a polymer film having a fixed liquid crystal orientation was laminated on one surface of the substrate by heating and pressing to form a cholesteric liquid crystal layer. . On the surface of the cholesteric liquid crystal layer thus formed, a holographic image having an irregular shape with a predetermined logo mark was formed by an embossing method. On the cholesteric liquid crystal layer 7 on which the hologram image is formed, γ-Fe ₂ O ₃ magnetic fine particles and a magnetic recording layer 3 made of urethane resin are applied to a thickness of 15 μm (after drying). Then, a concealing layer 4 made of aluminum powder and an acrylic resin is applied on the magnetic recording layer so as to cover the entire magnetic recording layer so as to have a thickness of 20 μm (after drying). did.

  On the formed concealing layer, a fluorescent ink layer (thickness 3 μm) containing a blue coloring fluorescent agent is a vertical pattern, and a fluorescent ink layer (thickness 3 μm) containing a red coloring fluorescent agent is a horizontal pattern. Then, it was formed by printing with a letterpress printing method. Further, the adhesive layer 10 mainly composed of vinyl chloride-vinyl acetate copolymer resin (Tg is 60 ° C.) is applied to cover the fluorescent ink layer and the concealing layer so as to have a thickness of 4 μm. Thus, a transfer foil of Example 3 was produced (see FIG. 5A).

Example 4
The transfer foil 11 of Example 3 and the transparent polyethylene terephthalate film adherend 13 having a thickness of 175 μm are overlapped so that the adhesive layer 10 of the transfer foil 11 and the adherend 13 are in contact with each other. The substrate of the transfer foil 11 is peeled off from the adherend 13 by pressurization and heating with a hot stamp, and the adhesive layer 10, the fluorescent ink layer 5, the concealing layer 4, and the magnetism are formed on the adherend 13. A recording medium of Example 4 having a configuration in which the recording layer 3 and the cholesteric liquid crystal layer 7 were sequentially laminated was produced (see FIG. 5B). This recording medium could be easily produced by the thermal transfer method using the transfer foil 11.

  On the recording medium, the date of birth and address variable information of the individual who will be the owner of the recording medium are written and recorded in the magnetic recording layer. In the obtained recording medium, the fluorescent ink layer on the magnetic recording layer was able to recognize the two-color fluorescent ink layer through the adherend, and their fluorescent luminance was high. Also, when observing from the cholesteric liquid crystal layer side of the recording medium, the hologram image formed on the cholesteric liquid crystal layer is observed with a unique hue that exhibits the characteristics of selective reflection of circular light and selective polarization of cholesteric liquid crystal. The anti-counterfeiting property was high and the design property was also high.

(Example 5)
The transfer foil produced in Example 3 was changed to a configuration in which the hologram forming layer 8 and the transparent reflective layer 6 were provided between the cholesteric liquid crystal layer 7 and the magnetic recording layer 3. That is, a hologram forming layer 8 (thickness: 2.0 μm) mainly composed of a melamine-based crosslinkable ultraviolet curable resin having a hologram image having a concavo-convex shape with a predetermined logo mark, and a transparent reflecting layer 6 (thickness) on which titanium oxide is deposited. 500 mm) was provided by a thermal transfer method. The above hologram image is a condition provided on the surface in contact with the transparent reflective layer. However, the conditions were such that there was no hologram image on the surface of the cholesteric liquid crystal layer 7 of the transfer foil produced in Example 3. Otherwise, the transfer foil of Example 5 was produced in the same manner as Example 3 (see FIG. 6A).

(Example 6)
The transfer foil 11 of Example 5 and the transparent polyethylene terephthalate film adherend 13 having a thickness of 175 μm are overlapped so that the adhesive layer 10 of the transfer foil 11 and the adherend 13 are in contact with each other. The substrate of the transfer foil 11 is peeled off from the adherend 13 by pressurization and heating with a hot stamp, and the adhesive layer 10, the fluorescent ink layer 5, the concealing layer 4, and the magnetism are formed on the adherend 13. A recording medium of Example 6 having a configuration in which the recording layer 3, the transparent reflection layer 6, the hologram forming layer 8, and the cholesteric liquid crystal layer 7 were sequentially laminated was produced (see FIG. 6B). This recording medium could be easily produced by the thermal transfer method using the transfer foil 11.

  On the recording medium, the date of birth and address variable information of the individual who will be the owner of the recording medium are written and recorded in the magnetic recording layer. In the obtained recording medium, the fluorescent ink layer on the magnetic recording layer was able to recognize the two-color fluorescent ink layer through the adherend, and their fluorescent luminance was high. Further, when viewed from the cholesteric liquid crystal layer side of the recording medium, the hologram image formed on the hologram forming layer is highly visible due to the transparent reflective layer, and the reflection of the cholesteric liquid crystal against the black background of the surface of the magnetic recording layer. Through the cholesteric liquid crystal layer in which the hue changes depending on the viewing angle, the color can be observed with a unique hue, and the anti-counterfeiting property is high and the design property is also high.

DESCRIPTION OF SYMBOLS 1 Recording medium 2 Transparent base material 3 Magnetic recording layer 4 Concealment layer 5 Fluorescent ink layer 6 Transparent reflection layer 7 Cholesteric liquid crystal layer 8 Hologram formation layer 9 Base material 10 Adhesive layer 11 Transfer foil 12 Thermal transferable layer 13 Substrate

Claims (8)

Sequential images of a black magnetic recording layer, a concealing layer made of aluminum powder and an acrylic resin, and a fluorescent ink layer that develops fluorescence when irradiated with black light on the other side of a transparent substrate having a cholesteric liquid crystal layer on one side A recording medium characterized by being laminated. Before KiToru Akirasei substrate, between the magnetic recording layer of the black, the hologram forming layer and a transparent reflective layer, the transparent provided the reflective layer and successively to the magnetic recording layer is in contact, the hologram forming layer The recording medium according to claim 1, wherein the recording medium is recognizable through a transparent substrate and a cholesteric liquid crystal layer. With a transparent base material having a cholesteric liquid crystal layer on one side, a black magnetic recording layer, a concealing layer made of aluminum powder and an acrylic resin, and a fluorescent ink layer that develops fluorescence when irradiated with black light. A recording medium characterized by sequentially laminating images. A hologram forming layer and a transparent reflective layer are sequentially provided between the cholesteric liquid crystal layer and the black magnetic recording layer so that the transparent reflective layer and the black magnetic recording layer are in contact with each other, and the hologram forming layer is transparent. The recording medium according to claim 3, wherein the recording medium can be recognized through the conductive substrate and the cholesteric liquid crystal layer. 4. The recording medium according to claim 1, wherein the image formed by the fluorescent ink layer is composed of two color fluorescent agents of blue color and red color. A cholesteric liquid crystal layer, a black magnetic recording layer, a concealing layer made of aluminum powder and an acrylic resin , an image with a fluorescent ink layer that develops fluorescence when irradiated with black light , and an adhesive layer are sequentially laminated on one side of the substrate. Transfer foil characterized by A hologram forming layer and a transparent reflective layer are sequentially provided between the cholesteric liquid crystal layer and the black magnetic recording layer so that the transparent reflective layer and the black magnetic recording layer are in contact with each other. Item 7. The transfer foil according to Item 6 . The transfer foil according to claim 6, wherein the image formed by the fluorescent ink layer is composed of two color fluorescent agents of blue color and red color.

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