JPH11198537A - Composite for heat-sensitive destruction pattern formation - Google Patents

Abstract

(57) [Problem] To provide a composite such as a card capable of recording an invisible information pattern by thermal destruction, a method of forming an invisible information pattern by thermal destruction, and a method of reading an invisible information pattern. . The composite has at least a heat-sensitive destruction layer, a detection layer which is substantially transparent in a visible light region and can be detected under irradiation with excitation light, and a synoptic layer having an appearance substantially equivalent to the heat-sensitive destruction layer. . The heat-sensitive destruction layer is, for example, a metal deposition layer.
A method for producing a composite having an invisible pattern that forms a pattern that cannot be recognized by the naked eye by partially removing the heat-sensitive destruction layer of the composite by thermal destruction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a composite suitable for forming an invisible information pattern, and a method for forming and reading an invisible information pattern.

[0002]

2. Description of the Related Art Printed materials such as labels and cards provided with a code pattern such as a bar code which can be detected by optical means have been widely used in distribution management systems. Further, for the purpose of preventing such disguise, or for maintaining the aesthetic appearance of an article provided with such a label or the like, a printed matter that is invisible to the naked eye and can be detected by infrared rays or the like has been proposed (for example, Japanese Patent Application Laid-Open No. 9-313382).
No. 9-30104). In these printed patterns, the code pattern is formed by printing a pattern with an infrared absorbing ink or by pattern printing a reflective layer on the infrared absorbing layer. These pattern printings are performed by, for example, screen printing, and practically, it is desired that they can be formed by a simpler method.

[0003] In addition to magnetic recording, cards such as telephone cards, orange cards, and highway cards are used to visually confirm the recorded information. (For example, JP-A-59-199284,
No. 60-52390). In these cards,
The recorded information is intended for visual confirmation, and in order to enhance the contrast of the reflectance between the heat-sensitive destruction layer and the exposed base that has been destroyed, a colored base may be used or a colored layer may be used as the base layer. Provided. Recording methods such as thermal recording and discharge breakdown recording are simple and widely used methods. However, if visual confirmation is possible, it cannot be applied to an article for which counterfeiting is to be avoided or an article for which confidential information is to be recorded. Thermal destruction recording is a simple and widespread method, but there is no known means capable of recording an invisible information pattern by thermal destruction.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide means capable of recording an invisible information pattern due to thermal destruction. More specifically, the object of the present invention is to
It is an object of the present invention to provide a composite such as a card capable of recording an invisible information pattern by thermal destruction, a method of forming an invisible information pattern by thermal destruction, and a method of reading an invisible information pattern.

[0005]

SUMMARY OF THE INVENTION The present invention provides a heat-sensitive rupture layer,
The present invention relates to a composite having at least a detection layer that is substantially transparent in a visible light region and can be detected under irradiation with excitation light, and a synoptic layer having an appearance substantially equivalent to the heat-sensitive destruction layer. Further, the present invention provides a composite comprising at least a heat-sensitive destruction layer, a detection layer which is substantially transparent in a visible light region and can be detected under irradiation with excitation light, and at least a synoptic layer having an appearance substantially equivalent to the heat-sensitive destruction layer. The present invention relates to a method for producing a composite having an invisible pattern, characterized in that the heat-sensitive rupture layer of the body is partially removed by heat rupture to form a pattern that cannot be recognized by the naked eye. The invisible pattern is, for example, an information pattern. In addition, the present invention relates to a method for detecting an invisible pattern, which comprises irradiating a complex having an invisible pattern produced by the method of the present invention with a detection layer excitation light to detect the pattern. The present invention also relates to a method for reading an invisible information pattern, which comprises irradiating a composite having an invisible information pattern produced by the method of the present invention with excitation light from a detection layer to read an information pattern.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The heat-destructible pattern-forming composite The heat-destructible composite of the present invention comprises a heat-sensitive destructive layer, a detection layer which is substantially transparent in a visible light region and can be detected under irradiation with excitation light, and the heat-sensitive destructive layer. It has at least an envisioned layer having an appearance substantially equivalent to the layer. The heat-sensitive destruction layer may be a layer made of a material that is removed by being scattered or evaporated by heating, and may be, for example, a metal deposition layer. The metal deposition layer may be made of a metal or a metal compound having a relatively low melting point, for example, Te, Sn, In, Al,
It can be composed of a metal comprising Bi, Pb and Zn, an alloy containing at least one of these metals, and at least one selected from the group consisting of compounds of these metals. The detection layer may be any layer that is substantially transparent in the visible light region and that can be detected under irradiation with excitation light, such as an ultraviolet absorber, an ultraviolet fluorescent agent, and an infrared ray that can be detected under irradiation with excitation light. It may contain an absorber or an infrared fluorescent agent. Furthermore, the detection layer can be made substantially transparent in the visible light region by appropriately adjusting the thickness, the added amount of the ultraviolet absorber, the particle size, and the like. In addition, the detection layer is composed of a material that is substantially invariant under conditions where the heat-sensitive layer is thermally broken.

Examples of the ultraviolet absorber include benzophenones (for example, 2-hydroxy-4-methoxybenzophenone, 2,2 order | dihydroxy-4-methoxybenzophenone, 2-hydroxy-4-n-octoxybenzophenone), Benzotriazoles (for example, 2-
(5-methyl-2-hydroxyphenyl) -benzotriazole, 2- [2-hydroxy-3,5-bis (α,
α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (3,5-di-t-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2-
(3-t-butyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5-
Di-tert-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5-di-tert-amyl-2-hydroxyphenyl) benzotriazole, 2-
(2 order | hydroxy-5 order | t-octylphenyl) benzotriazole, 2- (2-hydroxy-5-t-octyl) benzotriazole), titanium oxide, zinc oxide and the like.

The ultraviolet fluorescent agent is, for example, a substance that emits luminescence, and includes both inorganic fluorescent materials and organic fluorescent materials. As the inorganic phosphor, Ca, Ba, M
g, mainly composed of crystals such as oxides such as Zn and Cd, sulfides, silicates, phosphates and tungstates;
A pigment obtained by adding a metal element such as n, Zn, Ag, Cu, Sb, or Pb or a rare earth element such as a lanthanoid as an activator and calcining the same can be used. Preferred phosphors are ZnO: Zn, Br5 (PO4) 3Cl:
Eu, Zn ₂ GeO ₄ : Mn, Y ₂ O ₃ : Eu, Y (P,
V) O ₄ : Eu, Y ₂ O ₂ Si: Eu, Zn ₂ GeO ₄ :
Mn and the like can be exemplified. Examples of the organic phosphor include diaminostilbene disulfonic acid derivatives, imidazole derivatives, coumarin derivatives, derivatives such as triazole, carbazole, pyridine, naphthalic acid, imidazolone, dyes such as fluorescein and eosin, and compounds having a benzene ring such as anthracene. obtain.

[0009] As the infrared absorber, for example, JP-A-9
Inorganic substances such as ytterbium oxide described in JP-A-104857 and ytterbium phosphate described in JP-A-8-143853 and JP-A-9-143448 can be exemplified.
Further, as the infrared absorbing agent, a transparent dye having an absorption at an oscillation wavelength of a red light emitting diode or a semiconductor laser and having no absorption in a visible light region can be mentioned. As such a dye, for example, a cyanine dye-based dye Phthalocyanine, naphthoquinone, anthraquinone, dithiol complex, and triphenylmethane.

As the infrared fluorescent agent, for example, there are YF ₃ : Yb, Er, ZnS: Cu, Co and the like. Further, there is a type having a characteristic of emitting infrared light of wavelength λ2 in response to excitation light of wavelength λ1, and having characteristics of λ1 ≠ λ2 and λ1 <λ2. As such an infrared fluorescent agent, for example, the composition is LiNd _0.9 Yb _0.1 P ₄ O ₁₂ , LiBi _0.2 Nd _0.7 Yb _0.1 P ₄ O ₁₂ , NaN
d _0.9 Yb _0.1 P ₄ O ₁₂ , Nd _0.8 Yb _0.2 Na ₅ (WO ₄ ) ₄ , Nd _0.8 Yb _0.2 Na ₅
(Mo _0.5 W _0.5 O ₄ ) ₄ , Ce _0.05 Gd _{0.05 Nd 0.75} Yb _0.15 Na ₅ (Mo _0.7 W
_0.3 O ₄ ) ₄ , Nd _0.9 Yb _0.1 Al ₃ (BO ₃ ) ₄ , Nd _0.9 Yb _0.1 Al _2.7 Cr _0.3
(BO ₃ ) ₄ , Nd _0.5 Yb _0.4 P ₃ O ₁₄ , Nd _0.8 Yb _0.2 K ₃ (PO ₄ ) _{2 and the} like. These are all pump light (λ1) 800
Infrared (λ2) having a remarkable peak in the emission spectrum at 980 to 1020 nm is emitted upon receiving an infrared ray of nm.

The synoptic layer is not particularly limited as long as it has substantially the same appearance as the above-mentioned heat-sensitive destruction layer. However, besides the appearance, the encapsulation layer is composed of a material that is substantially invariant under conditions in which the thermally rupture layer is thermally ruptured. The passivation layer can be, for example, a metal deposition layer or a layer containing a metal pigment. The metal deposition layer can be appropriately selected from the materials listed for the heat-sensitive destruction layer. However, from the viewpoint that the heat-sensitive destruction layer is substantially invariable under the conditions of heat-sensitive destruction, when both the heat-sensitive destruction layer and the synoptic layer are metal-deposited layers, the metal-deposited layer constituting the heat-sensitive destruction layer is It is appropriate to use a metal having a lower melting point than the metal vapor deposition layer constituting the synoptic layer. Alternatively, from the viewpoint that the heat-sensitive destruction layer is substantially invariable under the condition of heat-sensitive destruction, when the heat-sensitive destruction layer and the entrainment layer are metal deposited layers of the same material, the heat-sensitive destruction layer is more layered than the entrapment layer. Suitably, the thickness is small.

In the case of a layer containing a metal pigment, as the metal pigment, the metabolic layer has substantially the same appearance as that of the heat-destructible layer, and the metal layer is substantially subjected to heat-destructive conditions. It can be appropriately selected in consideration of the fact that it is unchanged. Examples of the metal pigment include metal and metal compound pigments exemplified as the material constituting the metal deposition layer. Further, the layer containing the metal pigment may contain a binder suitable as a medium for dispersing the metal pigment. The binder can be appropriately selected in consideration of the fact that the encapsulating layer has substantially the same appearance as that of the heat-sensitive destruction layer and is substantially invariable under the conditions under which the heat-sensitive destruction layer is thermally destructed. As the resin constituting the binder, generally, proteins, rubber, celluloses, shellac, copal, starch, rosin and other natural resins,
Thermosetting of thermoplastic resin such as vinyl resin, acrylic resin, styrene resin, polyolefin resin, novolac phenol resin, resol phenol resin, urea resin, melamine resin, polyurethane resin, epoxy resin, unsaturated polyester, etc. Resin and the like. Furthermore, if necessary, the flexibility of the print film, a plasticizer for strength stability, viscosity adjustment, a solvent for drying,
Further, auxiliaries such as drying, viscosity, dispersibility, and various reactants can be appropriately added. Further, a photopolymerization-curable or electron beam-curable ink that does not use a solvent can be used as a binder. The main component is an acrylic resin,
Specifically, a commercially available acrylic monomer can be used.

The composite of the present invention can have a substrate, a magnetic recording layer, or a magnetic recording layer and a substrate adjacent to the envisioned layer. As the substrate, for example, vinyl chloride, nylon, cellulose diacetate, cellulose triacetate, polystyrene, polyethylene, polypropylene,
Plastics such as polyester, polyimide, and polycarbonate, metals such as copper and aluminum, paper, impregnated paper, and the like can be used alone or in combination as a composite. Physical properties required as a substrate, for example, strength,
A preferable material may be appropriately selected from the above materials in consideration of rigidity, concealing property, light opacity, and the like. In addition, the thickness of the base is usually about 0.005 to 5 mm.

As the magnetic recording layer, for example, γ-F
e ₂ O ₃ , Co-deposited γ-Fe ₂ O ₃ , Fe ₃ O ₄ , CrO ₂ , Fe, Fe-Cr, Fe-C
o, a conventionally known magnetic fine particle such as Co-Cr, Co-Ni, MnAl, Ba ferrite or Sr ferrite is dispersed in a suitable resin or ink vehicle, and a dispersion is obtained by a gravure method, a roll method, a knife edge method, etc. Can be formed on a substrate by a conventionally known coating method. Also, the magnetic recording layer
A metal such as Fe, Fe-Cr, Fe-Co, or Co-Cr or an alloy thereof can be formed on a substrate by a vacuum deposition method, a sputtering method, a plating method, or the like. FIG. 1 shows an example of the composite 10 of the present invention having a magnetic recording layer and a substrate. In the figure, a base material 1, a magnetic recording layer 2, a synoptic layer 3, a detection layer 4, and a heat-sensitive destruction layer 5 are shown in this order from the bottom.

Further, the composite of the present invention may have a hiding layer and / or a protective layer adjacent to the heat-sensitive destruction layer. Examples of the concealing layer include those containing a binder and a colored pigment shown below. As the binder, for example, ethyl cellulose, ethyl hydroxyethyl cellulose, cellulose acetate propionate, a cellulose derivative such as cellulose acetate, polystyrene, a styrene resin such as poly-α-methylstyrene or a styrene copolymer resin, polymethyl methacrylate,
Polyethyl methacrylate, polyethyl acrylate, acrylic resin such as polybutyl acrylate or methacrylic resin alone or copolymer resin, rosin, rosin modified maleic resin, rosin modified phenol resin, rosin ester resin such as polymerized rosin, poly Examples include, but are not limited to, vinyl acetate resins, coumarone resins, vinyl toluene resins, vinyl chloride resins, polyester resins, polyurethane resins, butyral resins, and the like.

The following pigments can be mentioned as colored pigments. Yellow: Fast Yellow G (Yellow-1) Fast Yellow 10G (Yellow-3) Disazo Yellow AAA (Yellow-12) Disazo Yellow AMX (Yellow-13) Disazo Yellow AAOT (Yellow-14) Disazo Yellow AAAA (Yellow-17) Yellow Iron Yellow-42) Disazo Yellow HR (Yellow-83)

Yellow-red (orange): Ortho-nitroanilina orange (Orange-2) Dinitroaniline orange (Orange-5) Disazoo-orange PMP (Orange-13) Vulcan orange (Dianisidine orange) (Oran
Ge-16)

Red: Toluidine red (Red-3) Chlorinated rose red (Red-4) Naphthol carmine FB (Red-5) Naphthol red M (Red-17) Brilliant fast scarlet (Red-22) Naphthol red 23 (Red) -23) Pyrazolone red (Red-38) Barium red 2B (Red-48: 1) Calcium red 2B (Red-48: 2) Strontium red 2B (Red-48: 3) Manganese red 2B (Red-48: 4) Barium Risole Red (Red-49: 1) Lake Red C (Red-53: 1) Brilliant Carmine 6B (Red-57: 1) Pigment Scarlet 3B Lake (Red-60:
1) Rake Bordeaux 10B (Red-63: 1) Anthosine 3B lake (Red-66) Anthosine 5B lake (Red-67) Rhodamine 6G lake (Red-81) Eosin lake (Red-90) Bengal (Red-101) Naphthol Red FGR (Red-112)

Purple: Rhodamine B lake (Violet-1) Methyl violet lake (Violet-3) Quinacridone red (Violet-19) Dioxazine violet (Violet-23)

Blue: Victoria Pure Blue BO Lake (Blue-1) Basic Blue 5B Lake (Blue-3) Basic Blue 6G Lake (Blue-9) Phthalocyanine Blue (α-form, unstable form) (Blue-
15: 1) phthalocyanine blue (β-form, non-crystalline form) (Blue-
15: 3) Phthalocyanine blue (β-form, non-crystalline, non-assembled) (B
blue-15: 4) Fast Sky Blue (Blue-17: 1) Alkaline Blue G Toner (Blue-18) Alkaline Blue R Toner (Blue-19) Peacock Blue Lake (Blue-24) Navy Blue (Blue-27) Ultramarine ( Blue-29) Reflex Blue 2G (Blue-56) Reflex Blue R (Blue-61)

Green: Brilliant Green Lake (Green-1) Diamond Green Thioflavin Lake (Green)
-2) Phthalocyanine Green G (Green-7) Green Gold (Green-10) Phthalocyanine Green Y (Green-36)

The protective layer can be formed, for example, using the same resin as used for the binder. Preferably, it is formed using a photopolymerization-curable or electron-curable ink containing an acrylic monomer as a main component without using a solvent. As the acrylic monomer, those described above can be used in the same manner. In addition, the above-mentioned ink contains additives such as a polymerization initiator in addition to the monomer as described above, and these additives are appropriately selected from phosphors and those having transparency to emitted light. FIG. 2 shows an example of the composite of the present invention having a protective layer and a substrate. In the figure, in order from the bottom, a substrate 1, an entrainment layer 3, a detection layer 4, a heat-sensitive destruction layer 5, and a protective layer 6
It is. In the composite of the present invention, an anchor layer may be provided between the above-mentioned base material, synovial layer, detection layer, heat-sensitive destruction layer, hiding layer and protective layer. The anchor layer is formed by a known coating method using an anchor layer paint appropriately selected in consideration of the properties of the binder resin constituting each layer. The anchor layer plays a role in increasing the adhesion between the layers. As the binder polymerization used for the anchor layer,
Examples include polyester resin, vinyl chloride / vinyl acetate copolymer, polyurethane resin, polyvinyl butyral resin, acrylic resin, cellulose resin, styrene / maleic acid copolymer resin, rubber-based resin, polyvinylidene chloride resin, and polyamide resin. The composite of the present invention may be in the form of, for example, a card, a label, or the like, but is not limited thereto.

Method for Preparing a Composite Having an Invisible Pattern A composite having a pattern that cannot be recognized by the naked eye can be formed by partially removing the heat-destructible layer of the composite of the present invention by heat-sensitive destruction. The invisible pattern may be an information pattern, and the information pattern may include a character, a number, a symbol, a pattern, and a barcode (1).
And two-dimensional). Thermal destruction
Discharge breakdown, breakdown by a thermal head, or breakdown by laser beam irradiation can be used. Both methods,
Known methods and apparatuses can be applied as they are. Invisible pattern detection / reading method The composite of the present invention having the invisible pattern prepared above can be irradiated with the detection layer excitation light to detect the pattern. Further, when the invisible pattern is an invisible information pattern, the information pattern can be read. The wavelength and intensity of the excitation light to be irradiated can be appropriately determined according to the absorbing agent and the fluorescent agent contained in the detection layer, and using a known excitation light,
For example, irradiation can be performed as laser light or the like. Further, pattern detection and reading can also be performed using known methods and apparatuses as they are.

[0024]

According to the present invention, there are provided a composite such as a card capable of recording an invisible information pattern by thermal destruction, a method of forming an invisible information pattern by thermal destruction, and a method of reading the invisible information pattern. can do. The composite of the present invention can record an invisible information pattern due to simple and widespread thermal destruction,
This is extremely useful in fields that require forgery prevention and concealment of confidential information.

[0025]

The present invention will be further described with reference to the following examples. Example 1 (Composite Having Ultraviolet-Excited Fluorescent Ink Layer) Transparent PET (5
0 μm) Al was vacuum-deposited on a substrate at 700 ° C. to a thickness of 70 nm. An OP ink layer (thickness: 2 μm) having the following composition is formed on the vapor-deposited layer, an ultraviolet excitation fluorescent ink layer (thickness: 3 μm) having the following composition, and an O layer having the following composition:
The P ink layer (film thickness: 2 μm) was sequentially coated by gravure printing. Further, Sn was deposited thereon at 230 ° C. to a thickness of 80 nm. An OP ink layer (film thickness 2 μm) having the following composition was gravure coated on the vapor deposition layer. Next, a natural rubber-based latex was applied as a pressure-sensitive adhesive to the back surface of the base material to a thickness of 20 μm, and a release paper was further applied thereon. Finally, the composite of the present invention was obtained by performing slit and roll processing.

UV-excited fluorescent ink composition Green luminescent ink (NS colorless fluorescent green 50) Fluorescent pigment (GOF-C: manufactured by Nemoto Special Chemical) 50 parts by weight Micro silica 4 parts by weight Organic bentonite 1 part by weight Alkyd resin 37 parts by weight Petroleum-based Solvent 8 parts by weight OP ink composition Byron 200 (polyester resin) 30 parts by weight Toluene 40 parts by weight MEK 30 parts by weight

A thermal printer (BC-1)
2W: Autonics) at 300 ° C. to print a barcode. In the obtained composite, the pattern was hardly visible visually. Further, a bar code reading test was performed on the obtained composite using a fluorescent touch scanner (manufactured by Nippon Denso Co., Ltd., irradiation wavelength: 365 nm, detection wavelength: 505 nm).

Example 2 (Composite Having Infrared Absorbing Ink Layer) Transparent PET (50
μm) Al was vacuum-deposited on a substrate at 700 ° C. to a thickness of 70 nm. OP ink layer as in Example 1 on the vapor deposition layer
(Film thickness: 2 μm), an infrared absorbing ink layer (film thickness: 5 μm) having the following composition, and an OP ink layer (film thickness: 2 μm) similar to that of Example 1 were successively applied thereon by gravure printing. Further, Sn was deposited thereon at 230 ° C. to a thickness of 80 nm. The same OP ink layer (film thickness: 2 μm) as in Example 1 was gravure coated on the deposited layer. Next, a natural rubber-based latex was applied as a pressure-sensitive adhesive to the back surface of the base material to a thickness of 20 μm, and a release paper was further applied thereon. Finally,
The composite of the present invention was obtained by slitting and rolling.

Infrared absorbing ink composition pigment (ytterbium oxide) 30 parts by weight Byron 200 (polyester resin) 30 parts by weight Toluene 20 parts by weight MEK 20 parts by weight

A thermal printer (BC-1)
2W: Autonics) at 300 ° C. to print a barcode. In the obtained composite, the pattern was hardly visible visually. Further, a bar code reading test was performed on the obtained composite using an infrared touch scanner (manufactured by Optoelectronics, irradiation wavelength: 940 nm, detection wavelength: 960 nm).

Example 3 (Composite Having a Colored Concealing Ink Layer and an Infrared Absorbing Ink Layer) A transparent PET (50 μm) substrate was treated with Al at 700 ° C.
Then, vacuum deposition was performed to a film thickness of 70 nm. An OP ink layer (thickness: 2 μm) as in Example 1 above the vapor-deposited layer, a colored concealment ink layer (thickness: 2 μm) having the following composition, and an infrared absorbing ink layer as in Example 2 above (Thickness: 5 μm), and an OP ink layer (thickness: 2 μm) similar to that of Example 1 was sequentially applied thereon by gravure printing. In addition, Sn
Was deposited at 230 ° C. to a thickness of 80 nm. An OP ink layer (film thickness: 2 μm) and a color concealment ink layer (film thickness: 2 μm) having the following composition as in Example 1 were successively gravure coated on the vapor deposited layer. Next, a natural rubber-based latex was applied as a pressure-sensitive adhesive to the back surface of the base material to a thickness of 20 μm, and a release paper was further applied thereon. Finally, the composite of the present invention was obtained by performing slit and roll processing.

Hidden ink composition pigment (Disazo Yellow AAMX) 10 parts by weight Byron 200 (polyester resin) 50 parts by weight Toluene 20 parts by weight MEK 20 parts by weight

A thermal printer (BC-1)
2W: Autonics) at 300 ° C. to print a barcode. The pattern of the obtained composite became more difficult to visually recognize as compared with the case where the pattern was not concealed (Example 2). Further, a bar code reading test was performed on the obtained composite using an infrared touch scanner (manufactured by Optoelectronics, irradiation wavelength: 940 nm, detection wavelength: 960 nm).

Example 4 (Composite Having Infrared Fluorescent Ink Layer) Transparent PET (50
μm) Al was vacuum-deposited on a substrate at 700 ° C. to a thickness of 70 nm. OP ink layer as in Example 1 on the vapor deposition layer
(Film thickness: 2 μm), an infrared fluorescent ink layer having the following composition (film thickness: 5 μm), and an OP ink layer (film thickness: 2 μm) similar to that of Example 1 were successively applied thereon by gravure printing. Further, Sn was deposited thereon at 230 ° C. to a thickness of 80 nm. The same OP ink layer (film thickness: 2 μm) as in Example 1 was gravure coated on the deposited layer. Next, a natural rubber-based latex was applied as a pressure-sensitive adhesive to the back surface of the base material to a thickness of 20 μm, and a release paper was further applied thereon. Finally,
The composite of the present invention was obtained by slitting and rolling.

Infrared absorbing ink composition Infrared emitting phosphor (Nd _0.1 Yb _0.1 Y _0.8 PO ₄ ) 40 parts by weight Byron 200 (polyester resin) 20 parts by weight Toluene 20 parts by weight MEK 20 parts by weight

A thermal printer (BC-1)
2W: manufactured by Autonics) at 300 ° C. The pattern of the obtained composite was almost invisible visually. Further, a wavelength of 8
Excitation was performed with a 10-nm light source, and luminescence intensity was measured by receiving luminescence with a silicon photodetector having a peak sensitivity of 980 nm. As a result, it was confirmed that the light emission luminance was sufficient for reading the pattern.

Example 5 (Composite Having Ultraviolet Absorbing Ink Layer) Transparent PET (50
μm) Al was vacuum-deposited on a substrate at 700 ° C. to a thickness of 70 nm. OP ink layer as in Example 1 on the vapor deposition layer
(Thickness: 2 μm), an ultraviolet absorbing ink layer having the following composition (thickness: 3 μm), and an OP ink layer (thickness: 2 μm) similar to that of Example 1 were successively applied thereon by gravure printing. Further, Sn was deposited thereon at 230 ° C. to a thickness of 80 nm. The same OP ink layer (film thickness: 2 μm) as in Example 1 was gravure coated on the deposited layer. Next, a natural rubber-based latex was applied as a pressure-sensitive adhesive to the back surface of the base material to a thickness of 20 μm, and a release paper was further applied thereon. Finally,
The composite of the present invention was obtained by slitting and rolling.

UV absorbing ink composition pigment (titanium oxide) 15 parts by weight Acrylic resin 30 parts by weight Toluene 30 parts by weight MEK 25 parts by weight

A thermal printer (BC-1)
2W: manufactured by Autonics) at 300 ° C. The pattern of the obtained composite was almost invisible visually. Further, a wavelength of 3
The reflectance was measured by irradiating 65 nm ultraviolet rays. As a result, it was confirmed that there was a sufficient reflectance difference for reading the pattern.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view of a composite of the present invention having a magnetic recording layer and a substrate.

FIG. 2 is a schematic explanatory view of a composite of the present invention having a protective layer and a substrate.

Claims (15)

[Claims] 1. A heat-sensitive destruction layer, a layer which is substantially transparent in a visible light region and can be detected under irradiation with excitation light (hereinafter referred to as a detection layer), and a layer having substantially the same appearance as the heat-sensitive destruction layer (Hereinafter referred to as a synoptic layer). 2. The heat-sensitive destruction layer is a metal deposition layer.
The complex according to any one of the above. 3. The method according to claim 1, wherein the metal deposition layer is made of Te, Sn, In, A
The composite according to claim 2, comprising a metal consisting of l, Bi, Pb, and Zn, an alloy containing at least one of these metals, and at least one selected from the group consisting of compounds of these metals. 4. The composite according to claim 1, wherein the detection layer contains an ultraviolet absorber, an ultraviolet fluorescent agent, an infrared absorber, or an infrared fluorescent agent. 5. The composite according to claim 1, wherein the synoptic layer is a metal deposition layer or a layer containing a metal pigment. 6. The composite according to any one of claims 1 to 5, wherein the detection layer and the entrainment layer are substantially invariant under conditions where the heat-sensitive destruction layer is thermally destructed. 7. The heat-sensitive destruction layer and the contemporaneous layer are metal deposited layers, and the metal-deposited layer forming the heat-sensitive destruction layer has a lower melting point than the metal-deposited layer forming the constitutive layer. A conjugate according to any one of the preceding claims. 8. The composite according to claim 1, wherein the heat-sensitive destruction layer and the entrainment layer are metal deposited layers of the same material, and the heat-sensitive destruction layer is thinner than the entrapment layer. 9. The composite according to claim 1, further comprising a base material, a magnetic recording layer, or a magnetic recording layer and a base material adjacent to the synoptic layer. 10. The composite according to claim 1, further comprising a hiding layer and / or a protective layer adjacent to the heat-sensitive destruction layer. 11. A composite comprising at least a heat-sensitive destruction layer, a detection layer which is substantially transparent in the visible light region and can be detected under irradiation with excitation light, and a synoptic layer having an appearance substantially equivalent to the heat-sensitive destruction layer. A method for producing a composite having an invisible pattern, wherein the heat-sensitive destruction layer of the body is partially removed by heat-destruction to form a pattern that cannot be recognized by the naked eye. 12. The method according to claim 11, wherein the invisible pattern is an information pattern. 13. The method of claim 13, wherein the heat-sensitive destruction is performed by a discharge, a thermal head,
Or heating by laser light irradiation.
Or the method of 12. 14. A method for detecting an invisible pattern, comprising irradiating a composite having an invisible pattern produced by the method according to claim 11 with a detection layer excitation light to detect the pattern. 15. A method for reading an invisible information pattern, comprising irradiating a composite having an invisible information pattern produced by the method according to claim 12 with a detection layer excitation light to read the information pattern.