JP2006082545A - Thermal recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermal recording medium that can enhance protection effectiveness against forgery. <P>SOLUTION: This thermal recording medium has, as a center piece, an optical diffraction structure layer 20 which is composed of an optical diffraction structure cambium 20A having a hologram or diffraction grating pattern on the whole surface, and a pattern reflective layer 20B with a predetermined image pattern on its rear surface. In addition the optical diffraction structure layer 20 is laminated with, on its front face side, the thermal recording layers 3A, 3B of which colorings come out differently depending upon the pre-conditions if the colorings are transparent or translucent before heating, and at the same time this optical diffraction structure layer 20 has, on its rear face side, a gluing layer that has the almost same index of refraction as that of the optical diffraction structure cambium A and is cemented with substrate 10. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a thermal recording medium provided with a thermal recording layer.

  Various cards such as credit cards or deposit / savings cards, transportation commuter pass tickets, or ID cards usually have information such as the name and number of each owner, validity period, or riding section according to the purpose of use. Selected and recorded as visual information. When recording information as visual information, a thermal coloring method that requires a short time for recording and does not require a large apparatus is often used. As the thermosensitive coloring method, an irreversible method is usually used, so although tampering is difficult, the visual information obtained is not so high in resolution and the color density is constant, so it is possible to try counterfeiting with a color copier, etc. There is sex.

  Conventionally, in order to prevent counterfeiting by color copiers, advanced inks such as using special inks that use dichroic dyes or forming fine tints that are visible to the naked eye but cannot be copied at the copier resolution Attempts have been made to use printing technology. However, when recording information by the thermal coloring method as visual information, the coloring hue is determined in advance by the material, and it is difficult to increase the resolution. Difficult to do.

  As a forgery prevention card, a substrate, a reflective layer, and a patterned thermotropic polymer liquid crystal layer are formed in this order, and the thermotropic polymer liquid crystal layer is heated and pressed to give liquid crystal properties, and a polarizing film A structure in which the pattern of the thermotropic polymer liquid crystal layer can be seen through the film is proposed. (Patent Document 1).

The anti-counterfeit card described in Patent Document 1 has a latent image that cannot be seen with the naked eye, and the latent image is visualized through a polarizing film, and a unique color is visible. It is said that the judgment is possible. However, if a thermographic polymer liquid crystal layer having a pattern as described in Patent Document 1 is laminated adjacent to a heat-sensitive recording layer on which recording is performed by heat-sensitive color development, and then heated and pressed to finish, the heat-sensitive recording is performed. The layer may also develop color. In addition, it is possible to apply the same recording as a latent image to the thermotropic polymer liquid crystal layer when recording on the thermal recording layer, but individual information is usually recorded on the thermal recording layer. It is difficult to have a certain latent image, which is not preferable for authenticity determination.
Japanese Unexamined Patent Application Publication No. 2004-122666 (Claim 1).

  An object of the present invention is to provide a heat-sensitive recording medium that can improve the effect of preventing forgery.

  In order to solve the above problems, the invention of claim 1 is directed to an optical diffraction structure having an optical diffraction structure forming layer provided with a hologram or a diffraction grating pattern, and a reflective layer provided on the back surface of the optical diffraction structure forming layer. A heat-sensitive recording medium comprising: a layer; and a heat-sensitive recording layer that is laminated on the light diffraction structure layer and that develops color when heated.

According to a second aspect of the present invention, there is provided the thermal recording medium according to the first aspect, wherein the hologram or the diffraction grating pattern is provided on the entire surface of the optical diffraction structure forming layer. is there.
The invention of claim 3 is the heat-sensitive recording medium according to claim 1 or 2, wherein the reflective layer is transparent or translucent.
According to a fourth aspect of the present invention, in the heat-sensitive recording medium according to the first to third aspects, the reflective layer is a partially reflective layer partially provided on the back surface of the light diffraction structure forming layer. The heat-sensitive recording medium is characterized.
According to a fifth aspect of the present invention, there is provided the thermal recording medium according to the fourth aspect, wherein the partial reflection layer is a pattern reflection layer having a planar shape formed from a predetermined pattern. .
A sixth aspect of the present invention is the thermal recording medium according to the fourth or fifth aspect, wherein the refractive index is provided on the back surface of the light diffraction structure forming layer and has substantially the same refractive index as the light diffraction structure formation layer. A heat-sensitive recording medium comprising the same layer.
The invention according to claim 7 is the thermal recording medium according to any one of claims 1 to 6, wherein the thermal recording layer includes two or more layers having different colors. It is a thermal recording medium.
According to an eighth aspect of the present invention, in the thermal recording medium according to any one of the first to seventh aspects, the thermal recording layer is transparent or semi-transparent before heating color development. And a thermal recording medium.
The invention according to claim 9 is the sheet-like base material according to any one of claims 1 to 8, wherein the sheet-like base material is laminated on the back side with respect to the heat-sensitive recording layer and the light diffraction structure layer. And an adhesive layer that is laminated on the back side of the sheet-like substrate and can be attached to an adherend.
A tenth aspect of the present invention is the thermal recording medium according to any one of the first to ninth aspects, wherein the thermal recording medium is laminated on the back side of the thermal recording layer and the light diffraction structure layer, and is attached to the adherend. An adhesive layer that can be attached to the sheet, and a sheet-like base material that is laminated on the surface side of the heat-sensitive recording layer and the light diffraction structure layer, and is provided in a peelable manner. A thermosensitive recording medium, wherein the thermosensitive recording layer and the light diffraction structure layer can be transferred.
An eleventh aspect of the present invention is the thermal recording medium according to any one of the first to tenth aspects, further comprising an image receiving layer for receiving ink.
The invention of claim 12 is the heat-sensitive recording medium according to any one of claims 1 to 11, further comprising a tint block printing layer on which a forgery-preventing tint block is printed. It is.
According to a thirteenth aspect of the present invention, in the thermosensitive recording medium according to any one of the first to twelfth aspects, a machine-readable and / or writable information recording unit comprising a magnetic recording layer and / or an IC chip is provided. It is a thermosensitive recording medium characterized by comprising.

According to the present invention, the following effects can be obtained.
(1) In the present invention, the light diffraction structure layer includes a light diffraction structure formation layer provided with a hologram or a diffraction grating pattern, and a reflection layer provided on the back surface of the light diffraction structure formation layer. The thermosensitive recording layer is laminated on the light diffraction structure layer and develops color when heated.
As a result, since the pattern and hue of the light diffraction structure forming layer change depending on the viewing angle, the authenticity of the heat-sensitive information medium can be identified, and forgery by a copying machine or the like can be prevented. . Furthermore, information such as characters can be recorded on the thermal recording layer using a thermal printer or the like.

(2) In the present invention, since the hologram or the diffraction grating pattern is formed on the entire surface of the light diffraction structure forming layer, the effect of the hologram can be expressed on the entire surface.

(3) In the present invention, since the reflective layer is transparent or translucent, it is possible to visually recognize characters, patterns, and the like printed on the layer disposed on the back side of the reflective layer.

(4) In the present invention, since the reflection layer is a partial reflection layer partially provided on the back surface of the light diffraction structure formation layer, a hologram or a diffraction grating pattern is provided on the entire surface of the light diffraction structure formation layer. Even in such a case, an effect such as a hologram can be exhibited only in the range where the partial reflection layer is formed.

(5) In the present invention, since the planar shape of the partial reflection layer is a pattern reflection layer formed from a predetermined pattern, a predetermined pattern can be formed in addition to the effect of (4).

(6) Since the present invention includes the same refractive index layer that is provided on the back surface of the optical diffraction structure forming layer and has substantially the same refractive index as the optical diffraction structure forming layer, the optical diffraction structure forming layer and the same refractive index layer are provided. In the range where these are in direct contact with each other, the effect of a hologram or the like can be almost eliminated. (However, subtle holograms can be confirmed.)

(7) In the present invention, since the heat-sensitive recording layer includes two or more layers having different colors, recording of characters, symbols and the like can be performed in two or more colors, and a complicated visual effect can be obtained. Thereby, the effect of preventing forgery of the thermal recording medium can be further improved.

(8) In the present invention, since the heat-sensitive recording layer is transparent or translucent in a state before color development by heating, characters, symbols, holograms, etc. of each layer formed on the back side of the heat-sensitive recording layer are visually recognized. Can do.

(9) The present invention provides a sheet-like base material laminated on the back side of the thermosensitive recording layer and the light diffraction structure layer, and an adhesive that is laminated on the back side of the sheet-like base material and can be attached to an adherend. Since it is provided with a layer, it can be used as a thermal recording medium label.

(10) In the present invention, the adhesive layer that can be attached to the adherend is laminated on the back side of the heat-sensitive recording layer and the light diffraction structure layer, and the sheet-like substrate is formed of the heat-sensitive recording layer and the light diffraction layer. It is laminated on the surface side of the structural layer and is provided so as to be peelable. The heat-sensitive recording layer and the light diffraction structure layer can be transferred to the adherend.
Thereby, it can be used as a thermal recording medium transfer sheet.

(11) Since the present invention includes an image receiving layer for receiving ink, it is possible to improve printing characteristics, printing strength, and the like.

(12) Since the present invention includes the tint block printing layer on which the forgery-preventing tint block is printed, the anti-counterfeiting effect of the thermal recording medium can be further improved.

(13) Since the present invention includes a machine-readable and / or writable information recording unit comprising a magnetic recording layer and / or an IC chip, invisible information is stored in the magnetic recording layer or information is written to the IC chip. Can read.

  FIG. 1 is a diagram showing a laminated structure of a thermal recording medium of the present invention, and FIG. 2 is a diagram showing a form suitable for applying the thermal recording medium of the present invention to a target article (adhered body). 3 and 4 are diagrams showing an embodiment of a thermal recording medium to which the present invention is applied.

  As shown in FIG. 1A, a thermosensitive recording medium 1 of the present invention is basically a thermosensitive recording layer 3 laminated on an optical diffraction structure layer 2 that gives a hologram or a diffraction grating pattern. The structure layer 2 is composed of a light diffraction structure forming layer 2A having fine unevenness of the light diffraction structure on the lower surface side and a reflection layer 2B formed along the fine unevenness. As shown in FIG. 1B, the heat-sensitive recording medium 1 of the present invention has the heat-sensitive recording layer 3 as the heat-sensitive recording layer A (reference numeral: 3A) and the heat-sensitive recording layer B (reference numeral: 3B) from the light diffraction structure layer 2 side. 2), or although not shown, the thermal recording layer 3 may be composed of three or more layers. Details of the light diffraction structure layer 2 are the same as those described with reference to FIG.

  The light diffractive structure forming layer 2A of the light diffractive structure layer 2 is a fine layer for providing a hologram or a diffraction grating pattern on one side of a layer made of a transparent synthetic resin, usually in order to avoid contamination or damage. Concavities and convexities are provided. Alternatively, in the case of a volume hologram, a transparent synthetic resin layer is provided with a diffraction grating for providing a hologram or a diffraction grating pattern, and in any case, basically transparent It is.

  As the light diffraction structure forming layer 2A, the former having fine irregularities is suitable for mass production by a method such as hot pressing. As a hologram and a diffraction grating pattern, either a plane hologram or a volume hologram can be used. A relief hologram, a Lippmann hologram, a Fresnel hologram, a Fraunhofer hologram, a lensless Fourier transform hologram, a laser reproduction hologram (image hologram, etc.), white Examples include mechanically formed diffraction gratings such as optical reproduction holograms (rainbow holograms), color holograms, computer holograms, hologram displays, multiplex holograms, holographic stereograms, holographic diffraction gratings, and electron beam direct drawing.

  As a material constituting the light diffraction structure forming layer 2A, a hologram or a diffraction grating pattern can be reproduced by casting or embossing. The photosensitive resin composition which can shape | mold a hardening part can be utilized. Specifically, for example, thermoplastic resins such as polyvinyl chloride, acrylic (polymethyl methacrylate), polystyrene, or polycarbonate, unsaturated polyester, melamine, epoxy, polyester (meth) acrylate, urethane (meth) acrylate, epoxy ( It is a thermosetting resin such as (meth) acrylate, polyether (meth) acrylate, polyol (meth) acrylate, melamine (meth) acrylate, or triazine-based acrylate, each of which is individual, thermoplastic resin, or thermosetting resin. It may be a mixture of each other or a mixture of a thermoplastic resin and a thermosetting resin. An ionizing radiation curable resin composition having a radically polymerizable unsaturated group and having thermoformability or a radically polymerizable unsaturated monomer added can also be used. The thickness of the light diffraction structure forming layer 2A is preferably about 1 to 2 μm, and when a coating composition such as an ionizing radiation curable resin composition is used, a transparent synthetic resin film is used as an object to be coated. Good.

Since the reflection layer 2B cannot obtain the visibility of the light diffraction pattern by the light diffraction structure formation layer 2A alone, or can obtain only a very low visibility even if it is obtained, the back surface of the light diffraction structure formation layer 2A. It is the layer provided in. As the reflective layer 2B, a reflective metal thin film made of a metal such as aluminum is provided, or a transparent thin film made of a material having a refractive index different from that of the light diffraction structure forming layer 2A is provided. If the metal thin film has a normal thickness, for example, about 50 nm, it is opaque, so that the lower layer is concealed. These metal thin film and transparent thin film function as the reflective layer 2B, and both can be formed by a vapor phase method such as vapor deposition. Examples of the transparent thin film include ZnS, TiO ₂ , Al ₂ O ₃ , Sb ₂ S ₃ , or SiO having a higher refractive index than that of the light diffraction structure forming layer 2A, or a refractive index higher than that of the light diffraction structure forming layer 2A. Low LiF, MgF ₂ or AlF ₃ . Since a general light-reflective metal thin film such as aluminum also becomes transparent when the thickness is 20 nm or less, a transparent material made of a material having a light refractive index different from that of the light diffraction structure forming layer 2A as described above. The same effect as a thin film. Furthermore, a transparent synthetic resin having a different light refractive index from that of the light diffraction structure forming layer 2A may be used. In this case, the reflective layer 2B can be formed on the back surface of the light diffraction structure forming layer 2A by, for example, printing.
Whether the reflective layer 2B is transparent or opaque is determined by whether or not the visibility of an image or the like provided in the lower layer should be ensured. That is, by making the reflective layer 2B transparent or semi-transparent, it is possible to visually recognize characters, patterns, and the like printed on the layer disposed on the back side of the reflective layer 2B.

  As the synthetic resin constituting the light diffraction structure forming layer 2A, it is desirable to select and use a hard resin having excellent wear resistance and contamination resistance. However, these synthetic resins have the ability to form holograms and the like. Since it is selected first, an OP layer (not shown), which is a transparent protective layer, is laminated on the upper surface of the light diffraction structure layer 2 as another layer as necessary in order to further strengthen. It is preferable to do. As the resin for forming the OP layer, a thermoplastic resin may be used, but a thermosetting resin composition using a thermosetting resin, or an ionizing radiation curable resin composition that is cured by ultraviolet ray or electron beam irradiation, etc. The physical and chemical performances can be further improved by using the above curable compound and heating after coating, or by irradiating with ionizing radiation and crosslinking curing. The thickness of the OP layer is preferably about 2 μm because of the enhancement of the protective function and the desire to reduce the thickness. As the ionizing radiation curable resin composition, a prepolymer, an oligomer and / or a monomer having a polymerizable unsaturated bond or an epoxy group in the molecule are appropriately mixed. The ionizing radiation refers to an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing or cross-linking molecules, and usually an ultraviolet ray or an electron beam is used.

  Examples of prepolymers and oligomers in the ionizing radiation curable resin composition include unsaturated polyesters such as unsaturated dicarboxylic acid and polyhydric alcohol condensates, polyester methacrylate, polyether methacrylate, polyol methacrylate, melamine methacrylate, etc. Examples include methacrylates, polyester acrylates, epoxy acrylates, urethane acrylates, polyether acrylates, polyol acrylates, acrylates such as melamine acrylate, and cationic polymerization type epoxy compounds. These prepolymers and oligomers are used in combination with one or more polyfunctional monomers or monofunctional monomers as necessary. In order to give ordinary application suitability to ionizing radiation curable resin compositions The prepolymer or oligomer is preferably 5% by weight or more, and the monomer and / or polythiol compound is preferably 95% by weight or less.

  When flexibility is required when an ionizing radiation curable resin composition is applied and cured, it is preferable to reduce the amount of monomer or use an acrylate monomer having 1 or 2 functional groups. When wear resistance, heat resistance, and solvent resistance are required when an ionizing radiation curable resin composition is applied and cured, ionizing radiation such as using an acrylate monomer with three or more functional groups A curable resin composition can be designed. Here, examples of the functional group having 1 include 2-hydroxy acrylate, 2-hexyl acrylate, and phenoxyethyl acrylate. Examples of the functional group having 2 include ethylene glycol diacrylate and 1,6-hexanediol diacrylate. Examples of the functional group having 3 or more include trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, and dipentaerythritol hexaacrylate.

  When hardening after application | coating of an ionizing radiation curable resin composition is performed by ultraviolet irradiation, a photoinitiator and a photoinitiator are added. As the photopolymerization initiator, in the case of a resin system having a radical polymerizable unsaturated group, acetophenones, benzophenones, thioxanthones, benzoin, benzoin methyl ether and the like are used alone or in combination. In the case of a resin system having a cationic polymerizable functional group, an aromatic diazonium salt, an aromatic sulfonium salt, an aromatic iodonium salt, a metatheron compound, a benzoin sulfonic acid ester or the like is used alone or as a mixture as a photopolymerization initiator. . The addition amount of a photoinitiator is 0.1-10 weight part with respect to 100 weight part of ionizing radiation-curable resin compositions.

In order to form the light diffraction structure forming layer 2A, after applying to an appropriate application target, a hologram or diffraction grating pattern is formed using a replication mold having fine irregularities on the mold surface to give a hologram or diffraction grating pattern. After shaping, after shaping, if it is a curable resin, cure by taking a curing means, and when using a photosensitive resin composition, develop with an appropriate developer, By revealing fine irregularities.
With the above configuration, since the light diffraction structure layer 2 changes in pattern and hue according to the viewing angle, the authenticity of the thermal recording medium 1 can be identified, and forgery by a copying machine or the like can be prevented. be able to.

  The heat-sensitive recording layer 3 is formed from a material that develops color when heated, and is printed using a thermal printer or the like. The thermosensitive recording layer 3 is composed of, for example, an electron donating dye precursor and an electron accepting compound as main components. As the electron-donating dye precursor, any leuco dye that is applied to this kind of heat-sensitive material is arbitrarily applied, and it can be applied to yellow, magenta, cyan, or other hue systems depending on the application. A color is selected. For example, leuco compounds such as triphenylmethane, fluorane, phenothiazine, auramine, spiropyran, and indinophthalide are preferably used.

  The electron-accepting compound is used as a developer in combination with an electron-donating dye precursor, and specifically includes the following acidic substances. That is, phenolic substances such as bisphenol A, octylphosphonic acid, nonylphosphonic acid, decylphosphonic acid, dodecylphosphonic acid, tetradecylphosphonic acid, hexadecylphosphonic acid, octadecylphosphonic acid, eicosylphosphonic acid, etc., α-hydroxy Organic acids such as octanoic acid, α-hydroxydodecanoic acid, α-hydroxytetradecanoic acid, α-hydroxyhexadecanoic acid, or α-hydroxyoctadecanoic acid, metal complex compounds, thio Diphenylurea or quinones.

  The electron-donating dye precursor and the electron-accepting compound are dispersed in a binder resin to constitute the heat-sensitive recording layer 3. Examples of binder resins include starches, celluloses, gelatin, casein, polyvinyl alcohols, maleic anhydride copolymers, acrylics, styrene butadiene copolymer emulsions, urea resins, melamine resins, amide resins, or polyurethane resins. Various auxiliary agents can be used as necessary, for example, polyethylene wax or glyoxal as an antifoaming agent, stearic acid amide, behenic acid amide, methylenebisstearic acid amide, dibenzyl oxalate, or tolylbiphenyl as a sensitizer. Ether or the like, or pigments such as kaolin, clay, calcium carbonate, titanium oxide, styrene, or silica. The heat-sensitive recording layer 3 made of the above materials is usually a colorless, transparent or slightly haze layer. However, as long as the thickness is not excessive, it does not impair the transparency and has transparency in that sense. . That is, the hologram or the like of the light diffraction structure layer 2 formed on the back surface of the thermosensitive recording layer 3 can be visually recognized.

  When two or more thermosensitive recording layers 3 are provided, the materials constituting the layers can be selected so that the coloring hues of the layers are different, and two or more colors can be developed. When two or more heat-sensitive recording layers 3 are provided, the material constituting the heat-sensitive recording layer 3 is selected and formed so that the energy required for each layer to develop color differs. When the thermal recording layer 3 is laminated as two or more layers in contact with each other, for example, the thermal recording layer 3 is already provided based on the action of the solvent in the ink used to form the thermal recording layer to be provided later. Since the electron donating dye precursor and the electron accepting compound in the heat sensitive recording layer may react and develop color, the two or more different heat sensitive recording layers or between other layers and the heat sensitive recording layer May be provided with an intermediate layer made of a resin or the like for the purpose of separating the layers. By providing an intermediate layer, it is possible to create a difference in energy required for each of two or more different thermosensitive recording layers to develop a color, that is, to create an energy gap. The boundary when the layer is colored can be clarified, that is, the contrast can be clarified.

FIG. 2A is a diagram showing a thermal recording medium label 4 to which the present invention is applied.
As shown in FIG. 2A, the heat-sensitive recording medium label 4 has a light diffraction structure layer 2, a heat-sensitive recording layer 3 (ie, heat-sensitive recording medium 1), and a protective layer 7 in this order on the surface of the sheet-like substrate 5. The adhesive layer 6 is laminated on the back surface of the sheet-like substrate 5. That is, the thermosensitive recording medium label 4 is laminated on the back side of the thermosensitive recording layer 3 and the light diffraction structure layer 2 and on the back side of the sheet-like substrate 5, and the target article (cover) Since it is provided with an adhesive layer 6 (adhesive layer) that can be attached to an adhesive body, it is a thermal recording medium that can be used as a label.
The sheet-like substrate 5 is preferably present as an object to be formed when forming the light diffraction structure layer 2 or the heat-sensitive recording layer 3, or in the sense of imparting mechanical strength to the heat-sensitive recording medium label 4. You can also The protective layer 7 is for increasing the durability after the heat-sensitive recording medium label 4 is applied to the target article using the adhesive layer 6, but can also be omitted.
Further, as shown in FIG. 2B, the light diffraction structure layer 2 and the heat-sensitive recording layer 3 in the heat-sensitive recording medium label 4 are sheet-like, contrary to the case described with reference to FIG. The heat-sensitive recording layer 3 and the light diffraction structure layer 2 may be laminated in this order from the substrate 5 side.
When the sheet-like substrate 5 is transparent, the sheet-like substrate 5 is the uppermost layer, and the sheet-like substrate 5, the thermal recording layer 3, the light diffraction structure layer 2, and the adhesive layer 6 are arranged in this order from the upper side. You may laminate | stack, and the protective layer 7 may be laminated | stacked on the upper side of the sheet-like base material 5 in that case. Of course, the sheet-like substrate 5 may be the uppermost layer, and the sheet-like substrate 5, the light diffraction structure layer 2, the thermosensitive recording layer 3, and the adhesive layer 6 may be laminated in this order from the upper side. A protective layer 7 may be laminated on the upper side of the material 5.
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FIG. 2C is a diagram showing a thermal recording medium transfer sheet 8 to which the present invention is applied.
In FIG.2 (c), the protective layer 7 is laminated | stacked on the back surface of the sheet-like base material 5 so that peeling is possible, Furthermore, the thermal recording layer 3, the optical diffraction structure layer 2 (namely, thermal recording medium 1), adhesive layer 6 are laminated in order. That is, the heat-sensitive recording medium transfer sheet 8 is laminated on the back side of the heat-sensitive recording layer 3 and the light diffraction structure layer 2, and an adhesive layer 6 (adhesive layer) that can be attached to the target article (adhered body). And a sheet-like base material 5 which is laminated on the surface side of the heat-sensitive recording layer 3 and the light diffraction structure layer 2 and is provided so as to be peelable, so that it can be used as a transfer sheet. It is a medium.
The adhesive layer 6 can be omitted from the thermal recording medium transfer sheet 8 as long as the adhesive layer is formed on the surface of the target article during transfer. Moreover, although the protective layer 7 is for increasing the durability of the surface after performing transfer to the target article using the adhesive layer 6, it can also be omitted.
Further, as shown in FIG. 2D, the light diffraction structure layer 2 and the heat sensitive recording layer 3 in the heat sensitive recording medium transfer sheet 8 are formed from the light diffraction structure layer 2 and the heat sensitive recording layer 3 from the sheet-like substrate 5 side. It may be laminated in order. Also in this case, the adhesive layer 6 and the protective layer 7 can be omitted.

  As described with reference to FIGS. 2A to 2D, in the thermal recording medium label 4 and the thermal recording medium transfer sheet 8, the order of stacking the light diffraction structure layer 2 and the thermal recording layer 3 is arbitrary. Good. Further, an adhesive layer can be interposed between the respective layers as required.

  The sheet-like base material 5 is preferably used as a formation target when forming the light diffraction structure layer 2 and the heat-sensitive recording layer 3, and preferably has the meaning of imparting mechanical strength to the heat-sensitive recording medium transfer sheet 8. You can also

  As the sheet-like base material 5, it is possible to reduce the thickness, and it is preferable to have a solvent resistance and a heat resistance that can withstand processing when manufacturing a mechanical strength and authenticity determination medium. Since it depends on the purpose of use, it is not limited, but a film-like or sheet-like plastic is preferable. Examples include various plastic films or plastic sheets such as polyethylene terephthalate (PET), polycarbonate, polyvinyl alcohol, polysulfone, polyethylene, polypropylene, polystyrene, polyarylate, triacetyl cellulose (TAC), diacetyl cellulose, polyethylene vinyl alcohol, and the like. can do.

  The adhesive layer 6 is used to apply a thermal recording medium label 4, a thermal recording medium transfer sheet 8, and the like having the light diffraction structure layer 2, the thermal recording layer 3 (that is, the thermal recording medium 1), and the like to a target article. As the adhesive constituting the adhesive layer 6, a heat sensitive adhesive or a pressure sensitive adhesive can be used. In the case of the thermal recording medium label 4, a pressure sensitive adhesive that can be attached only by pressure is often used, and in the case of the thermal recording medium transfer sheet 8, it can be instantly transferred by heat and pressure. In this sense, a heat-sensitive adhesive is often used.

  In addition to general protection of the light diffraction structure layer 2 and the heat-sensitive recording layer 3, the protective layer 7 prevents surface deformation due to heat and pressure caused when recording on the heat-sensitive recording layer 3, and is resistant to chemicals. In addition to improving the property, water resistance, friction resistance, head matching properties, etc., it is also used for the purpose of improving transparency. As a material constituting the protective layer 7, a resin composition having desired physical properties as the surface protective layer is selected from those already mentioned as the binder resin constituting the thermosensitive recording layer 3. In particular, when surface scratch resistance, chemical resistance, and contamination resistance are required, a thermosetting resin, or an ionizing radiation curable resin such as an ultraviolet curable resin or an electron beam curable resin is usually used. In order to smoothly move the thermal recording medium label 4, the thermal recording medium transfer sheet 8, and the thermal head during recording on the thermal recording layer 3, the protective layer 7 has releasability. Preferably it is. For this reason, it is preferable to mix a release material such as silicone in the protective layer 7 or to coat the surface of the protective layer with a material containing the release material. The protective layer 7 is also required to have both printability and slipperiness since printing using a thermal transfer ribbon may be performed so that unauthorized rewriting cannot be performed after the thermal recording medium is used. Sometimes. In this case, after a layer having printability is first formed, a material including a releasable substance is used, for example, a point having a diameter of about 0.1 mm and a line having a width of about 0.1 mm are set to 0. By arranging the portions having the releasability and the portions having the printability by arranging them at intervals of about 2 mm or more, it is possible to have both properties.

  In the thermal recording medium transfer sheet 8, it is preferable that the thermal recording medium 1 is detachably laminated with the sheet-like substrate 5. When the protective layer 7 and other layers are present, it is only necessary to ensure releasability between the sheet-like substrate 5 and the layer in contact with the sheet-like substrate 5. Even if it is said to be peelable, an adhesive strength that does not peel is required until just before transfer. When a PET film is used as the sheet-like substrate 5, most of the binder resin in the paint or ink does not adhere firmly to the PET film and can be peeled off during transfer. If necessary, a binder resin having high adhesiveness may be added to increase the peel strength, or a peelable binder resin or material such as wax may be added to lower the peel strength.

  FIG. 3 is a diagram showing one embodiment of the thermal recording medium 9 of the present invention. As shown in FIG. 3 (a), the thermal recording medium 9 has a base material 10 in which a laminate composed of the light diffraction structure layer 2, the thermal recording layer 3 (that is, the thermal recording medium 1), and the protective layer 7 from the lower side. The magnetic recording layer 11 is laminated on the lower surface side of the base material 10 so that the reflective layer 2B side is in contact therewith. As shown in FIG. 3B, the thermosensitive recording medium 9 is based on a laminate composed of the thermosensitive recording layer 3, the light diffraction structure layer 2 (that is, the thermosensitive recording medium 1), and the protective layer 7 from the lower side. The magnetic recording layer 11 may be laminated on the material 10 so that the heat-sensitive recording layer 3 side is in contact therewith, and the magnetic recording layer 11 may be laminated on the lower surface side of the substrate 10.

  In the case where the thermal recording layer 3 of the thermal recording medium 9 as shown in FIG. 3B is subjected to thermal recording, the portion (= recording portion) colored by the recording of the thermal recording layer 3 is more than the thermal recording layer 3. Due to the action of the light diffraction structure layer 2 laminated on the top, an effect is produced in which the color of the recording portion appears to change when viewed from the upper surface side of the figure. For example, when the heat-sensitive recording layer 3 has two layers for black color development and red color development, by performing thermal recording, the recording part colored in red and the recording part colored in black are not colored. A solid visual part is produced, but a complicated visual effect is produced in which the color changes on the recording part colored in red, on the recording part colored in black, and on the plain part not colored. In this way, it is possible to make it difficult to counterfeit or to counterfeit a thing with a complicated visual effect, and it is possible to suppress copying using a color copier.

FIG. 4 is a diagram showing a thermal recording medium 9 which is one embodiment of the present invention.
The heat-sensitive recording medium 9 includes a magnetic recording layer 11, a base material 10, an intermediate layer 12A, a heat-sensitive recording layer A (reference 3A), an intermediate layer 12B, a heat-sensitive recording layer B (reference 3B), a light diffraction structure layer 2, from the lower surface side. And the protective layer 7 is laminated | stacked. The role of the intermediate layer B (reference numeral 12B) is as described above, but the role of the intermediate layer A is to prevent the thermal recording layer A from developing color when the substrate 10 and the thermal recording layer A are laminated. This is to thermally cut off between the material 10 and the heat-sensitive recording layer A.

  The laminate composed of the base material 10 and the magnetic recording layer 11 is widely used for various cards such as credit cards or savings cards, transportation commuter passes, identification cards, etc. The magnetic recording layer 11 Various information is recorded as invisible information, the recorded information is read using reading means, and predetermined steps are executed to settle the purchase price, deposit or withdraw cash, or pass through the gate , Etc. are performed.

  The base material 10 has strength and thickness according to the application, and is made of the same plastic film or plastic sheet as the material constituting the sheet-like base material 5 or paper, and if necessary, 2 -3 sheets or more may be combined.

  The magnetic recording layer 11 is (1) provided by directly applying to a base material 10 using a magnetic paint prepared by adding a material containing magnetic agent powder and kneading. (2) What is the base material 10? Applied to another thin plastic film, etc., cut into stripes and attached to the card substrate 10, or (3) Magnetic recording layer transfer prepared by being peelably laminated on a temporary substrate The sheet is formed by being transferred to the base material 10 by a transfer method. The magnetic recording layer 11 is formed as a thin film of a magnetic substance in a gas phase by vapor deposition or sputtering of the magnetic substance on the base material 10, or the formation of such a thin film is a base of a magnetic recording medium. It may be performed on a base material different from the material, and then cut and pasted into a stripe shape or applied by transfer.

  In the thermal recording 3 of the thermal recording medium 9, for example, information such as the name and number of each owner, the valid period, the boarding section, or the amount of money is recorded as visual information, and it is configured so that visual determination is possible. ing.

  Further, since the light diffraction structure layer 2 of the thermal recording medium 9 in the above example has an effect of changing the hue depending on the viewing angle, it gives an impression that reproduction by color copying is difficult, and an effect of preventing forgery occurs.

  In the heat-sensitive recording medium 9 of the above example, the magnetic recording layer 11 is provided as the information recording means on the base material 10. However, the magnetic recording layer 11 may be replaced with an IC chip, or the magnetic recording layer 11 And an IC chip may be provided.

  In the thermal recording medium 9 of the present invention, in addition to the visual information recording performed using the thermal recording layer 3, the name of the issuing organization, the name of the card, the cautionary note, the explanatory note, the amount for use as a voucher, etc. Information, an arbitrary pattern, or a color pattern may be provided. The information, the pattern, or the color pattern may be formed by an arbitrary means such as printing, and a portion to be formed includes the thermal recording layer 3. Any part may be used as long as it does not interfere with recording on the recording medium, and any part of the thermal recording medium 1, the thermal recording medium label 4, or the thermal recording medium transfer sheet 8 described above may be used. Good.

The description has been given of the embodiment in which the reflective layer 2B is provided on the entire back surface of the light diffraction structure forming layer 2A. Hereinafter, the thermal recording medium provided with the reflective layer partially patterned on the back surface of the light diffraction structure forming layer 2A. I will explain. Note that portions that perform the same functions as those of the above-described thermal recording medium 9 and the like are denoted by the same reference numerals, redundant description is omitted appropriately, and changes are mainly described. Further, the surface on which the print recorded on the heat-sensitive recording medium and the hologram recorded on the light diffraction structure forming layer can be visually recognized is defined as the front surface, and the opposite surface is defined as the back surface. To do.
FIG. 5 is a cross-sectional view showing the thermal recording medium 100 on which the light diffraction structure layer 20 is laminated.
As shown in FIG. 5, the thermal recording medium 100 includes a protective layer 7, a thermal recording layer 3, a base material 10, a magnetic recording layer 11 (described above), a light diffraction structure forming layer 20A, and a pattern reflection layer 20B. The optical diffraction structure layer 20 comprised from these, and the contact bonding layer 30 are provided.
The heat-sensitive recording medium 100 is formed so that an effect such as a hologram is positively exhibited only in a range where the pattern reflection layer 20B exists. Further, as described later, the thermal recording medium 100 uses a material having a refractive index equivalent to that of the optical diffraction structure forming layer 20A as the adhesive layer 30, so that the adhesive layer 30 and the optical diffraction structure formation layer 20A are In a direct contact range (that is, a range where the pattern reflection layer 20B does not exist), the effect of a hologram or the like can be almost eliminated. Hereinafter, each layer of the thermal recording medium 100 will be described in detail.

As shown in FIG. 5, the light diffractive structure layer 20 includes a light diffractive structure forming layer 20A having a hologram or diffraction grating pattern applied to the entire surface, and a pattern reflecting layer 20B provided by patterning a predetermined pattern on the back surface thereof. It consists of.
For the light diffraction structure forming layer 20A, various resin materials such as a thermosetting resin, a thermoplastic resin, and an ionizing radiation curable resin can be selected. Examples of the thermosetting resin include unsaturated polyester resins, acrylic urethane resins, epoxy-modified acrylic resins, epoxy-modified unsaturated polyester resins, alkyd resins, and phenol resins. Examples of the thermoplastic resin include acrylate resin, acrylamide resin, nitrocellulose resin, and polystyrene resin. These resins are used alone or as a copolymer of two or more. These resins may be used alone or in combination of two or more kinds of isocyanate resins, metal soaps such as cobalt naphthenate and zinc naphthenate, benzoyl peroxide, peroxides such as methyl ethyl ketone peroxide, benzophenone, acetophenone, anthraquinone, naphthoquinone, A heat or ultraviolet curing agent such as azobisisobutyronitrile or diphenyl sulfide may be blended. Examples of the ionizing radiation curable resin include epoxy acrylate, urethane acrylate, and acrylic-modified polyester. Other monofunctional or polyfunctional monomers, oligomers and the like can be conjugated to such an ionizing radiation curable resin for the purpose of adjusting the cross-linked structure and viscosity.

  The pattern reflection layer 20B is a layer for reflecting all or part of the light beam that has passed through the light diffraction structure forming layer 20A. When the amount of light rays reflected by the pattern reflection layer 20B is large, the light diffraction structure layer 20 becomes an opaque type hologram. When the amount of light rays passing therethrough is large, the light diffraction structure layer 20 becomes a transparent type hologram. . Here, the opaque type hologram means a hologram whose back side layer is less visible than the hologram part, while the transparent type hologram means a hologram whose back side layer is more easily visible than the hologram part. . That is, for example, when there is a printed layer or the like on the back side of the hologram, the opaque type cannot confirm the printed content from the front surface, whereas the transparent type visually recognizes the printed content or the like. be able to. The pattern reflection layer 20B can be formed by a method such as sublimation, vacuum deposition, sputtering, reactive sputtering, ion plating, electroplating, or printing.

  When the light diffraction structure layer 20 is formed into an opaque type hologram, the pattern reflection layer 20B is formed thick to increase the amount of reflected light. In this case, the pattern reflection layer 20B is made of, for example, Al, Cr, Ti, Fe, Co, Ni, Cu, Ag, Au, Ge, Mg, Sb, Pb, Cd, Bi, Sn, Se, In, Ga, Rb. Etc. and their oxides, nitrogen compounds, etc., alone or in combination of two or more. Among the above metal thin films, Al, Cr, Ni, Ag, Au and the like are particularly preferable, and the film thickness is in the range of 1 to 10,000 nm, desirably 2 to 200 nm.

On the other hand, when the light diffraction structure layer 20 is formed into a transparent type hologram, a transparent material having a large refractive index difference is used for the pattern reflection layer 20B, or a large amount of light passes through using a metal thin film. To do.
When a transparent substance is used for the pattern reflection layer 20B, it is formed by printing or the like using a transparent resin material having a refractive index different from that of the light diffraction structure forming layer 20A. The refractive index of the transparent resin material may be larger or smaller than the refractive index of the resin of the light diffraction structure forming layer 20A, but the difference in refractive index is preferably 0.1 or more, more preferably 0.5 or more. Preferably, 1.0 or more is optimal.
In the case where a metallic reflective film other than a transparent resin is used for the pattern reflective layer 20B, it is preferable to form it as thin as 20 nm or less in order to provide light transmittance. Examples of the transparent type reflective layer preferably used include titanium oxide (TiO ₂ ), zinc sulfide (ZnS), and Cu · Al composite metal oxide.

The pattern reflection layer 20B is formed using, for example, a water washing method, an etching method, or the like.
In the water washing method, water-soluble ink is provided in a pattern on the back surface of the light diffraction structure forming layer 20A, and further, for example, a metal layer is provided using a technique such as vapor deposition. That is, a metal layer is provided by masking the back surface of the light diffraction structure forming layer 20A with water-soluble ink. By washing this with water, only the water-soluble ink and the metal layer provided thereon are removed by washing, and the portion of the metal layer where the water-soluble ink did not exist remains to form the pattern reflection layer 20B. can do.
In the etching method, a metal layer is provided on the entire back surface of the light diffraction structure forming layer 20A, and then a pattern layer (resist layer) is provided with an acid-resistant and alkali-resistant resin for etching. In this case, the pattern reflection layer 20B can be formed by leaving the metal layer in a pattern in a portion where the resist layer exists.

  The adhesive layer 30 is a layer for adhering the base material 10 and the light diffraction structure layer 20 which are other layers. The adhesive layer 30 is a layer having substantially the same refractive index as that of the light diffraction structure forming layer 20A (hereinafter referred to as “the same refractive index layer”) by selecting one having the same refractive index as that of the light diffraction structure forming layer 20A. Most of the light rays that have passed through the light diffraction structure forming layer 20A can pass therethrough. Thereby, in the range where the adhesive layer 30 (the same refractive index layer) and the optical diffraction structure forming layer 20A are in contact with each other, the effect of the hologram or the like can be almost eliminated. However, also in this range, the hologram or diffraction grating pattern is applied to the entire surface of the light diffraction structure forming layer 20A. Therefore, the heat-sensitive recording medium 100 can confirm a subtle hologram or the like by using a measuring instrument or the like, and can determine authenticity.

FIG. 6 is a diagram showing a part of a thermal recording medium 100A, which is an example of the thermal recording medium 100 described above, from the surface.
The base material 10 of the heat-sensitive recording medium 100A is, for example, white. The thermosensitive recording layer 3 is made of a transparent or translucent material, and a ring is printed by a thermal printer or the like, and the range of the ring is colored, for example, red. The light diffractive structure layer 20 is patterned with the letters “DNP” on the light diffractive structure forming layer 20A, and the pattern reflecting layer 20B has a star shape (a shape as viewed from the surface side) with a star mark (predetermined pattern). ) Is patterned.

  Explaining how the heat-sensitive recording medium 100A appears, the heat-sensitive recording layer 3 is colored in red without lacking the entire range of the ring because no other print layer is formed on the surface side. In the range where “DNP” of the light diffractive structure forming layer 20A is patterned and the star mark of the pattern reflecting layer 20B overlap (indicated by a black area in the figure), the light diffractive structure layer 20 has an effect such as a hologram. Is expressed. On the other hand, in the range where the “DNP” of the light diffraction structure forming layer 20A and the star mark of the pattern reflection layer 20B do not overlap (indicated by the broken line in the figure), the effect of the hologram or the like is almost eliminated by the action of the adhesive layer 30. Like the surrounding area, the surface of the substrate 10 can be visually recognized. Further, in the range where the pattern reflection layer 20B is provided, a star-shaped pattern can be confirmed.

FIG. 7 is a cross-sectional view showing the thermal recording medium transfer sheet 200.
The thermal recording medium transfer sheet 200 is a transfer sheet that allows the thermal recording medium 100 to be adhered to an adherend.
The thermal recording medium transfer sheet 200 has a release layer and a sheet-like substrate 5 on the surface of the protective layer 7 (that is, the surface side of the thermal recording layer 3 and the light diffraction structure layer 20) with respect to the thermal recording medium 100. Then, the adhesive layer 30 is laminated on the back surface of the base material 10 (that is, the back surface side of the heat-sensitive recording layer 3 and the light diffraction structure layer 20). Thereby, the thermal recording medium transfer sheet 200 can transfer the thermal recording medium 100 to an adherend.
Note that the base material 10 may be omitted if not necessary, for example, because the mechanical strength of the thermal recording medium transfer sheet 200 is sufficient.
In addition, as shown in FIG. 7, an adhesive layer is provided between the optical diffraction structure layer 20 and the layer in contact with the optical diffraction structure layer 20 (in the case of FIG. 7, the base material 10). It does not have to be provided. In this case, the same effect as described above can be obtained by forming the layer (base material 10) in contact with the light diffraction structure layer 20 from a transparent or translucent material to have the same refractive index. .
Further, the magnetic recording layer 11 may not be provided if it is not necessary.

Thermal recording media 300 to 600 shown in FIGS. 8 to 11 are sectional views showing an example in which the configuration of the thermal recording medium 100 shown in FIG. 5 is changed.
The thermosensitive recording medium 300 shown in FIG. 8 is provided with two color thermosensitive recording layers 3A and 3B and intermediate layers 12A and 12B with respect to the thermosensitive recording medium 100 so that, for example, black and red can be developed. It is a thing.

A thermal recording medium 400 shown in FIG. 9 is obtained by changing the light diffraction structure layer 20 to the surface side of the thermal recording layers 3A and 3B with respect to the thermal recording medium 300.
In the thermal recording medium 400, an anchor layer 41 is provided between the light diffraction structure layer 20 and the thermal recording layer 3B for adhesion between the layers. In this case, by making the refractive index of the anchor layer 41 and the optical diffraction structure forming layer 20A substantially the same, the anchor layer 41 functions as a layer having the same refractive index, and a hologram in a range where these two layers are in direct contact with each other. The effects such as can be almost eliminated.
Further, the anchor layer 41 may be deleted when the light diffraction structure layer 20 and the thermosensitive recording layer 3B can be directly joined. In this case as well, the same effect as described above can be obtained by making the refractive index of the light diffraction structure forming layer 20A and the thermal recording layer 3B equal and causing the thermal recording layer 3B to function as the same refractive index layer.
The thermal recording medium 400 is not provided with a protective layer (see the protective layer 7 such as the thermal recording medium 300). This is because the thermal recording medium 400 has no problem with surface damage, dirt adhesion, and the like.

A thermal recording medium 500 shown in FIG. 10 is obtained by providing a printing layer or the like on the front side and the back side of the thermal recording medium 300. A primer 42A is applied to the back side of the magnetic recording layer 11 in order to improve the printing strength of the ink. An explanatory note print layer 43 is provided by using silk printing, offset printing or the like for explaining the usage method of the thermal recording medium 500 (for example, “notes on the use of a commuter pass” for a commuter pass). Further, a protective layer 7A is provided on the back surface side.
On the surface side of the protective layer 7B, a primer 42B and an image receiving layer 44 for improving the printing strength and the like are provided in order, and on the surface thereof, for example, to prevent forgery by copying using a copying machine or the like. A tint block printing layer 45 on which a tint block having a fine pattern is printed is provided by silk printing, offset printing, or the like. A lubrication layer 46 is laminated on the surface of the tint block printing layer 45, and friction between a feeding mechanism such as an inkjet printer or a thermal transfer printer for forming the printing layer 47 and the thermal recording medium 500, an inkjet head and the thermal recording medium 500 Friction etc. are reduced. The print layer 47 is a print layer provided on the surface of the thermal recording medium 500, and “invalid” is printed on a commuter pass whose expiration date has passed, using an inkjet printer, a thermal transfer printer, or the like.

  A thermal recording medium 600 shown in FIG. 11 is provided with an OP layer 48, a printing layer, etc. (descriptive text printing layer 43, tint block printing layer 45, printing layer 47) on the front and back sides of the thermal recording medium 400. . Since the configuration for providing the print layer and the like is the same as that of the thermal recording medium 500, the description thereof is omitted. The OP layer 48 is provided because the strength of the material differs or the adhesiveness with the upper layer differs depending on the type of the light diffraction structure layer 20.

As described above, the thermal recording medium 100A and the like have the pattern reflection layer 20B formed from stars (predetermined patterns). As a result, even if a hologram or diffraction grating pattern is formed on the entire surface of the light diffraction structure forming layer 20A, the effect of the hologram or the like can be expressed only in the range of the pattern reflection layer 20B, and the effect of preventing forgery can be improved. The star can be visually recognized when viewed from the surface.
The thermal recording medium 100 and the like are provided on the back surface of the light diffraction structure forming layer 20A and include the same refractive index layer having substantially the same refractive index as the light diffraction structure forming layer 20A. In the range where the layer having the same refractive index is in direct contact, the effect of a hologram or the like can be almost eliminated.
Further, the heat-sensitive recording medium 300 or the like is transparent or semi-transparent before heating and color development, and the heat-sensitive recording layers 3A and 3B are layers having different colors. For this reason, the hologram, printing, etc. of the layer formed in the back surface side rather than the thermosensitive recording layers 3A and 3B can be visually recognized. In addition, since the recording of characters, symbols, etc. can be performed in two or more colors and a complicated visual effect can be obtained, the effect of preventing forgery of the thermal recording medium can be further improved.

  A magnetic paint (barium ferrite: urethane resin: carbon = 36: 12: 2 50% solvent solution (solvent; toluene: MEK: MIBK = 20: 15: 15) was applied to the surface of a PET film having a thickness of 188 μm. It was dried and aged at a temperature of 80 ° C. to form a magnetic recording layer to obtain a laminated sheet composed of a PET film / magnetic recording layer, where the symbol “/” is before and after this symbol. It means that they are laminated together.

Separately from the above, a hologram layer-forming composition having the following composition was applied to the surface of a PET film having a thickness of 25 μm by a gravure coating method to form a hologram-forming resin film having a thickness of 2 μm.
(Hologram layer forming composition)
・ Acrylic resin ………………………………………………………… 40 parts by mass ・ Melamine resin ……………………………………………… ………………… 10 parts by mass ・ Cyclohexanone ………………………………………………………… 50 parts by mass ・ Methyl ethyl ketone …………………………… ………………………… 50 parts by mass

The hologram-forming resin film was embossed using a metal plate in which hologram interference fringes were formed in a concavo-convex shape to give holographic unevenness to form a hologram layer. Thereafter, aluminum was vapor-deposited on the resin surface provided with irregularities to a thickness of 30 nm to form a reflective layer.
Subsequently, a composition for forming a heat seal layer having the following composition is applied on the reflective layer by a gravure coating method to form a heat seal layer having a thickness of 2 μm. From the configuration of PET film / hologram layer / reflective layer / heat seal layer A transfer sheet was obtained.
(Heat seal layer forming composition)
・ Vinyl chloride / vinyl acetate copolymer resin ………………………………… 20 parts by mass ・ Acrylic resin …………………………………………………… ……… 10 parts by mass ・ Ethyl acetate …………………………………………………………… 20 parts by mass ・ Toluene …………………………… ……………………………………… 50 parts by mass

The laminated sheet composed of the PET film / magnetic recording layer prepared above is disposed so that the heat seal layer side of the transfer sheet obtained above is in contact with the PET sheet side of the laminated sheet, the temperature of the hot plate: 140 ° C., pressure Transfer was performed under the conditions of 20 kg / cm ² , and after the transfer, the PET film of the transfer sheet was peeled off to obtain a laminated sheet having a configuration of hologram layer / reflection layer / heat seal layer / PET film / magnetic recording layer.

  On the hologram layer of the obtained laminated sheet, two heat-sensitive recording layers and a protective layer for black color development and red color development were sequentially formed to obtain a heat-sensitive recording medium. As a paint for forming a heat-sensitive recording layer for black color development, 3- (N-ethyl-N-acylamino) -6-methyl-7-anilinofluorane, bisphenol A, and a binder solution (10% aqueous solution of polyvinyl alcohol) are used. As a coating material for forming a heat-sensitive recording layer for red color development, a coating comprising 3-diethylamino-7-chlorofluorane, 3,3-dichlorophenylthiourea, and a binder solution (10% aqueous solution of polyvinyl alcohol) is used. In addition, a urethane acrylate resin solution was used as the protective layer-forming coating material.

  A magnetic paint (barium ferrite: urethane resin: carbon = 36: 12: 2 50% solvent solution (solvent; toluene: MEK: MIBK = 20: 15: 15) was applied to the surface of a PET film having a thickness of 188 μm. It was dried and aged at a temperature of 80 ° C. to form a magnetic recording layer, and a laminated sheet having a PET film / magnetic recording layer configuration was obtained.

Separately from the above, a hologram layer-forming composition having the following composition was applied to the surface of a PET film having a thickness of 25 μm by a gravure coating method to form a hologram-forming resin film having a thickness of 2 μm.
(Hologram layer forming composition)
・ Acrylic resin ………………………………………………………… 40 parts by mass ・ Melamine resin ……………………………………………… ………………… 10 parts by mass ・ Cyclohexanone ………………………………………………………… 50 parts by mass ・ Methyl ethyl ketone …………………………… ………………………… 50 parts by mass

  The hologram-forming resin film was embossed using a metal plate in which hologram interference fringes were formed in a concavo-convex shape to give holographic unevenness to form a hologram layer. Thereafter, aluminum was vapor-deposited on the resin surface provided with irregularities to a thickness of 30 nm to form a reflective layer.

  A red color thermosensitive recording layer, an intermediate layer (1), a black color thermosensitive recording layer, and an intermediate layer (2) are sequentially formed on the reflective layer of the obtained laminated sheet to obtain a thermosensitive recording medium. It was. As a coating material for forming a heat-sensitive recording layer for red color development, a paint comprising 3-diethylamino-7-chlorofluorane, 3,3-dichlorophenylthiourea, and a binder solution (10% aqueous solution of polyvinyl alcohol) is used for black color development. The heat-sensitive recording layer-forming paint comprises 3- (N-ethyl-N-acylamino) -6-methyl-7-anilinofluorane, bisphenol A, and a binder solution (polyvinyl alcohol 10% aqueous solution). A thing was used. A urethane acrylate resin solution was used as a paint for forming the two intermediate layers (1) and (2).

Subsequently, on the intermediate layer (2), a composition for forming a heat seal layer having the following composition was applied by a gravure coating method to form a heat seal layer having a thickness of 2 μm, and a PET film / hologram layer / reflection layer / thermosensitive recording layer. A transfer sheet composed of (red) / intermediate layer (1) / thermosensitive recording layer (black) / intermediate layer (2) / heat seal layer was obtained.
(Heat seal layer forming composition)
・ Vinyl chloride / vinyl acetate copolymer resin ………………………………… 20 parts by mass ・ Acrylic resin …………………………………………………… ……… 10 parts by mass ・ Ethyl acetate …………………………………………………………… 20 parts by mass ・ Toluene …………………………… ……………………………………… 50 parts by mass

The laminated sheet composed of the PET film / magnetic recording layer prepared above is disposed so that the heat seal layer side of the transfer sheet obtained above is in contact with the PET sheet side of the laminated sheet, the temperature of the hot plate: 140 ° C., pressure Transfer is performed under the condition of 20 kg / cm ² , and after transfer, the PET film of the transfer sheet is peeled off, and the hologram layer / reflection layer / thermal recording layer (red) / intermediate layer (1) / thermal recording layer (black) / A laminated sheet having a configuration of intermediate layer (2) / heat seal layer / PET film / magnetic recording layer was obtained.

Next, the manufacturing method of Example 3 of the thermal recording medium to which the present invention is applied will be described.
The heat-sensitive recording medium A of Example 3 is a recording medium having a pattern reflection layer, and is a protective layer / heat-sensitive recording layer / OP layer / light diffraction structure layer (light diffraction structure forming layer / pattern reflection layer) / adhesive layer / base. It is composed of a material / magnetic recording layer.
(Preparation of base film)
A magnetic material (barium ferrite: urethane resin: carbon = 36: 12: 2) is applied to a PET film (base material), dried, and aged at 80 ° C. to prepare a base film composed of a base material / magnetic recording layer. did.

(Preparation of transfer film A)
A release layer / OP layer / light diffraction structure forming layer was coated on a sheet-like substrate formed of another PET film, and hologram processing was performed. After masking by printing a pattern with a water-based ink on the back surface of the light diffraction structure forming layer, vapor deposition was performed. This was washed with water and the aqueous ink was dropped to form a pattern reflection layer on the portion where the washing ink was not printed. Thus, a transfer film A composed of a sheet-like substrate / release layer / OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) was produced.

(Adhesion between base film and transfer film A)
Between the substrate surface of the substrate film produced as described above and the back surface of the light diffraction structure layer (light diffraction structure forming layer / pattern reflection layer) of the transfer film A, an adhesive layer is provided and bonded, By peeling off the sheet-like substrate, a laminated sheet A composed of OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) / adhesive layer / base material / magnetic recording layer was produced.
(Formation of thermal recording layer)
A heat-sensitive recording layer (black dye 3- (N-ethyl-N acylamino) -6-methyl-7-anilinofluorane), developer (bisphenol A, solvent) is formed on the surface of the laminated sheet A, that is, the surface of the OP layer. (Polyvinyl alcohol 10% aqueous solution) and a protective layer (urethane acrylate) were formed.

  Through the above steps, a thermal recording medium A composed of a protective layer / thermal recording layer / OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) / adhesive layer / base material / magnetic recording layer is produced. We were able to.

Next, a manufacturing method of Example 4 of the thermal recording medium to which the present invention is applied will be described.
The heat-sensitive recording medium B of Example 4 is obtained by further adding layers to the front and back surfaces of the heat-sensitive recording medium A produced in Example 3, and has an image receiving layer / protective layer / heat-sensitive recording layer / OP layer / light diffraction structure. Layer (light diffraction structure forming layer / pattern reflective layer) / adhesive layer / base material / magnetic recording layer / description printed layer / protective layer.
(Formation of image receiving layer and explanatory text printing layer)
The image receiving layer is formed by applying to the surface of the thermosensitive recording medium A produced in Example 3, that is, the surface of the protective layer (RL primer: XEL (D) curing agent: AF-WAX307 = 400: 20: 9). did.
The explanatory note printing layer was formed by printing an explanatory note on the back surface of the thermal recording medium A, that is, the back surface of the magnetic recording layer. The protective layer was formed by applying urethane acrylate to the back surface of the explanatory note printing layer.

  Image receiving layer / protective layer / thermosensitive recording layer / OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) / adhesive layer / base material / magnetic recording layer / description printed layer / The thermal recording medium B could be produced by drying and aging the sheet composed of the protective layer.

Next, a manufacturing method of Example 5 of the thermal recording medium to which the present invention is applied will be described.
The heat-sensitive recording medium C of Example 5 has an image receiving layer / OP layer / light diffraction structure layer (light diffraction structure forming layer / pattern reflective layer) / heat sensitive recording layer (red) / intermediate layer / heat sensitive recording layer (black) / protection. Layer / adhesive layer / base material / magnetic recording layer / description printed layer / protective layer.
Hereinafter, differences from the thermal recording media A and B will be mainly described.

(Preparation of base film)
Since it is the same as that of Example 3, it abbreviate | omits.
(Preparation of transfer film C)
First, as in Example 3, film C (transfer film A in Example 3) composed of a sheet-like substrate / release layer / OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) ) Was produced.
Next, in order to form the heat-sensitive recording layer (red) on the back surface of the film C, that is, the back surface of the light diffraction structure layer (light diffraction structure forming layer / pattern reflection layer), the heat-sensitive recording layer (red dye 3-diethylamino) is formed. -7-chlorofluorane), a developer (3,3-dichlorophenthiourea), and a solvent (polyvinyl alcohol 10% aqueous solution) were laminated. Further, a heat-sensitive recording layer (black) is formed through the same steps as in Example 3, and a sheet-like substrate / OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) / heat-sensitive recording layer (red) ) / Intermediate layer / thermosensitive recording layer (black) / protective layer. In this case, the light diffraction structure forming layer and the thermosensitive recording layer (red) were selected to have the same refractive index in order to substantially eliminate the effect of the hologram in the range where they are in direct contact.

(Adhesion between base film and transfer film C)
An OP layer / light diffractive structure layer (light diffractive structure layer) is obtained by providing an adhesive layer and bonding the base material surface of the base film and the back surface of the protective layer of the transfer film C and peeling the sheet-like base material. A laminated sheet C composed of a formation layer / pattern reflection layer) / thermosensitive recording layer (red) / intermediate layer / thermosensitive recording layer (black) / protective layer / adhesive layer / base material / magnetic recording layer was produced.
(Formation of image receiving layer and explanatory text printing layer)
An image receiving layer, an explanatory note printing layer, and a protective layer were formed by the same steps as in Example 4.

  Image receiving layer / OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) / heat-sensitive recording layer (red) / intermediate layer / heat-sensitive recording layer (black) / protective layer / The thermal recording medium C was able to be produced by drying and aging a sheet composed of an adhesive layer / base material / magnetic recording layer / description printed layer / protective layer.

Next, a manufacturing method of Example 6 of the thermal recording medium to which the present invention is applied will be described.
The heat-sensitive recording medium D of Example 6 has an OP layer / light diffraction structure layer (light diffraction structure forming layer / pattern reflection layer) / anchor layer / heat-sensitive recording layer (red) / heat-sensitive recording layer (black) / protective layer / adhesion. Layer / substrate / magnetic recording layer.
The heat-sensitive recording medium D is mainly different from the heat-sensitive recording medium A or the like in the manufacturing process of the light diffraction structure layer.

(Preparation of base film)
Since it is the same as that of Example 3, it abbreviate | omits.
(Preparation of transfer film D)
First, a release layer, an OP layer, and a light diffraction structure forming layer were provided on a sheet-like substrate formed from a PET film, and hologram embossing was performed on the light diffraction structure forming layer. The back surface of the light diffraction structure forming layer was subjected to corona treatment, and after printing a pattern with water-based ink, corona treatment, vapor deposition, and water washing were performed to form a pattern reflection layer. Thus, a demetalized hologram original fabric D composed of a sheet-like base material / OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) was produced.
Next, an anchor layer is applied to the back surface of the demetalized hologram original D, a heat-sensitive recording layer (red dye 3-diethylamino-7-chlorofluorane), a developer (3,3-dichlorophenthiourea), Solvent (polyvinyl alcohol 10% aqueous solution), thermal recording layer (black dye 3- (N-ethyl-N acylamino) -6-methyl-7-anilinofluorane), developer (bisphenol A, solvent (polyvinyl) A 10% aqueous solution of alcohol) and a protective layer (urethane acrylate) were formed, whereby a sheet-like substrate / OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) / anchor layer / thermosensitive recording layer ( A transfer film D comprising red) / thermosensitive recording layer (black) / protective layer was produced.
(Adhesion between base film and transfer film D)
The base material surface of the base material film and the back surface of the protective layer of the transfer film D were adhered by providing an adhesive layer, and the sheet-like base material was peeled off.

  Through the above steps, OP layer / light diffraction structure layer (light diffraction structure formation layer / pattern reflection layer) / anchor layer / heat-sensitive recording layer (red) / heat-sensitive recording layer (black) / protective layer / adhesive layer / base material / A thermosensitive recording medium D composed of a magnetic recording layer could be produced.

Samples of card and transportation commuter pass were prepared by adding layers as necessary to the thermal recording media A to D produced in Examples 3 to 6 and cutting them.
Further, it was visually confirmed that the effect of the hologram was positively exhibited only in the pattern reflective layer pattern and the range where the pattern reflective layer was formed.

(Modification)
The present invention is not limited to the embodiments described above, and various modifications and changes are possible, and these are also within the equivalent scope of the present invention.
(1) In Examples 1 and 2, an example using a metal plate for embossing was shown, but the present invention is not limited to this. Any plate that can be embossed may be used. For example, a resin plate may be used.

(2) In Example 3 and the like, the reflection layer is an example of a pattern reflection layer having a predetermined pattern, but the present invention is not limited to this. The reflective layer may not have a predetermined pattern. For example, a reflection layer (partial reflection layer) partially provided on the back surface of the light diffraction structure forming layer may be used (see the partial reflection layer 20C shown in FIG. 6).

It is a figure which shows the thermal recording medium 1 of this invention. It is a figure which shows the form which applies the thermosensitive recording medium of this invention to a target article. It is a figure which shows the thermal recording medium 9 of this invention. It is a figure which shows the thermal recording medium 9 of this invention. It is a figure which shows the thermal recording medium 100 of this invention. It is a figure which shows 100 A of thermal recording media of this invention from the surface. It is a figure which shows the thermal recording medium transfer sheet 200 of this invention. It is a figure which shows the thermal recording medium 300 of this invention. It is a figure which shows the thermal recording medium 400 of this invention. It is a figure which shows the thermal recording medium 500 of this invention. It is a figure which shows the thermal recording medium 600 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,9 Thermal recording medium 2 Optical diffraction structure layer 2A Optical diffraction structure formation layer 2B Reflective layer 3 Thermal recording layer 4 Thermal recording medium label 5 Sheet-like base material 7 Protective layer 8 Thermal recording medium transfer sheet 10 Base material 11 Magnetic recording layer DESCRIPTION OF SYMBOLS 20 Light diffraction structure layer 20A Light diffraction structure formation layer 20B Pattern reflection layer 30 Adhesive layer 43 Description printing layer 45 Copy-forgery-inhibited pattern printing layer 47 Printing layer 48 OP layer 100,100A, 300-600 Thermal recording medium 200 Thermal recording medium transfer sheet

Claims (13)

A light diffractive structure forming layer provided with a hologram or a diffraction grating pattern, and a light diffractive structure layer having a reflective layer provided on the back surface of the light diffractive structure forming layer;
A heat-sensitive recording layer laminated on the light diffraction structure layer and colored by heating;
A thermal recording medium comprising: The heat-sensitive recording medium according to claim 1,
The light diffraction structure forming layer has the hologram or the diffraction grating pattern applied to the entire surface,
A thermal recording medium characterized by the above. In the heat-sensitive recording medium according to claim 1 or 2,
The reflective layer is transparent or translucent;
A thermal recording medium characterized by the above. The thermal recording medium according to claim 1, wherein:
The reflective layer is a partially reflective layer partially provided on the back surface of the light diffraction structure forming layer;
A thermal recording medium characterized by the above. The thermal recording medium according to claim 4,
The partial reflection layer is a pattern reflection layer whose planar shape is formed from a predetermined pattern;
A thermal recording medium characterized by the above. In the heat-sensitive recording medium according to claim 4 or 5,
Provided on the back surface of the light diffraction structure forming layer, comprising a refractive index identical layer having substantially the same refractive index as the light diffraction structure formation layer;
A thermal recording medium characterized by the above. In the thermal recording medium according to any one of claims 1 to 6,
The heat-sensitive recording layer comprises two or more layers having different colors;
A thermal recording medium characterized by the above. The thermal recording medium according to any one of claims 1 to 7,
The heat-sensitive recording layer is transparent or semi-transparent before heating and coloring,
A thermal recording medium characterized by the above. In the heat-sensitive recording medium according to any one of claims 1 to 8,
A sheet-like base material laminated on the back side of the thermosensitive recording layer and the light diffraction structure layer; and
An adhesive layer that is laminated on the back side of the sheet-like base material and can be attached to an adherend;
A thermal recording medium characterized by the above. The thermal recording medium according to any one of claims 1 to 9, wherein
An adhesive layer that is laminated on the back side of the heat-sensitive recording layer and the light diffraction structure layer, and can be attached to an adherend;
A sheet-like base material that is laminated on the surface side of the thermosensitive recording layer and the light diffraction structure layer, and is provided so as to be peelable;
The thermosensitive recording layer and the light diffraction structure layer can be transferred to the adherend,
A thermal recording medium characterized by the above. In the thermal recording medium according to any one of claims 1 to 10,
Having an image receiving layer for receiving ink;
A thermal recording medium characterized by the above. The heat-sensitive recording medium according to any one of claims 1 to 11,
Having a tint block printing layer printed with anti-counterfeiting tint blocks;
A thermal recording medium characterized by the above. In the thermal recording medium according to any one of claims 1 to 12,
Comprising a machine-readable and / or writable information recording unit comprising a magnetic recording layer and / or an IC chip;
A thermal recording medium characterized by the above.

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