JPH10244747A - Infrared absorption printed matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an infrared absorption printed matter which reduces a manufacturing cost, has no limit to the color of a visible image to be formed, is excellent in concealability of a formed image pattern due to infrared absorption, and obviates the formation of a white color printed layer for concealment. SOLUTION: This infrared absorption printed matter has a base material 10, an infrared absorption layer consisting of at least one layer formed on one face side of the base material, and a camouflage pattern layer 31 visually recognizable by visible light, which is formed on one face side of, or on the other face side of, the infrared absorption layer. The infrared absorption layer has a first region A (21) having first infrared absorbing characteristics and a second region B (22) formed in a position different from the first region and having second infrared absorbing characteristics different from the first infrared absorbing characteristics, or infrared transmitting characteristics, and the first and second regions are constituted to have a color tone whose visual recognition is difficult under visible light.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a security print using an infrared absorbing ink. In particular, it is difficult to see under visible light, and it is possible to detect images by infrared detection device by irradiating infrared rays. Prevent counterfeiting of securities such as cash vouchers and prepaid cards, passports, ID cards, etc. Related to the printed matter that is needed to do so.

[0002]

2. Description of the Related Art Conventionally, printed matter, such as securities such as cash vouchers and prepaid cards, which need to be protected from forgery, can be visually recognized under ordinary visible light to enhance security. Ink has been developed which can detect an image visually or by an infrared detection camera by irradiating ultraviolet rays or infrared rays. For example, a fluorescent ink that emits fluorescence by irradiating ultraviolet rays and an infrared absorbing ink containing a material that absorbs infrared rays are known.

[0003] As the above-mentioned infrared absorbing ink, a transparent infrared absorbing ink containing a material having substantially no absorption in the visible light region and having absorption in the infrared region is known. A technology that makes it difficult to view under visible light by making the spectral characteristics of the visible region of the region where this transparent infrared absorbing ink is printed on the substrate similar to the spectral characteristics of the visible region of the substrate. It is disclosed in JP-A-4-70394. As a method of using such a transparent infrared absorbing ink,
A method of printing a transparent barcode with a transparent infrared-absorbing ink and using the code information with an infrared detector, or a method of printing a pattern in the printed material with a transparent infrared-absorbing ink and checking it with an infrared camera Etc. are known.

[0004] Further, Japanese Patent Application Laid-Open No. 3-114872 discloses that
Printing each ink in a predetermined pattern using an ink containing a photochromic compound that absorbs in the near-infrared region or infrared region by irradiation with ultraviolet light or other wavelengths, and an ink not containing it Printed matter is disclosed. By measuring the infrared absorption after the irradiation of the ultraviolet light, the printed matter can be distinguished from the part printed with the ink containing the photochromic compound and the part printed with the ink containing no photochromic compound.

As a non-transparent infrared absorbing ink, a black carbon ink is known. Infrared transmitting inks that do not absorb infrared rays, yellow, magenta,
By printing by overlaying cyan ink, a black print area can be obtained in the visible light area, but since it is infrared-transmissive, the black print area formed by carbon ink and the infrared transmission and absorption characteristics are different. Differently, both can be distinguished by the infrared irradiation means and the infrared detection means.

Japanese Patent Application Laid-Open No. 63-307996 discloses a red printed material which can be detected by an infrared sensor and has a printed area printed with a printing ink having a different infrared absorption characteristic. Outer absorption prints are disclosed. The printed matter further includes a first printing area made of a printing ink that absorbs infrared rays and a second printing area made of a general printing ink, and it is difficult to visually discriminate the color tone between the first printing area and the second printing area. Can be
Excellent concealment of image patterns formed by infrared absorption,
It can be used for general printed matter.

[0007] Further, Japanese Patent Application Laid-Open No. 3-114871,
It has a substrate with printing information, the substrate holds a region having characteristics that are invisible to the naked eye, and the region is
A region containing no dye having absorption in the near infrared or infrared region, which is visually the same as the surface, or containing a dye having the first mixture ratio, and a dye having absorption in the near infrared or infrared region, A printed matter comprising a combination with a region portion included in a mixing ratio is disclosed.

[0008]

However, in a printed material using the above-mentioned infrared absorbing ink, an infrared absorbing material or a photochromic compound used for the transparent infrared absorbing ink is a special material, so that it is expensive as a raw material. ,
There is a problem that the manufacturing cost increases. In addition, when the infrared absorption characteristics of black printing using carbon ink and black printing obtained by superimposing yellow, magenta, and cyan inks, which are infrared transmitting inks, are used, the color of a visible image to be formed is limited. There is a problem.

A first printing area made of a printing ink that absorbs infrared rays and a second printing area made of a general printing ink, so that the color tone of the first printing area and the second printing area are visually close to each other. In some cases, it has been desired to eliminate the difference in color tone between two regions having different infrared absorption characteristics and to further enhance the concealment of an image pattern formed by infrared absorption. When an infrared absorption pattern using a colored infrared absorption ink is formed in a color image, the color of the infrared absorption ink in the visible light region hinders the formation of a beautiful color image. It is necessary to print a white ink layer that transmits infrared light and has visual concealing properties on the upper layer of the absorbing ink layer, and form a color image with ordinary yellow, magenta, cyan, black, etc. ink on the upper layer. Yes, the printing layer for concealment had to be formed separately with a white ink.

Accordingly, an object of the present invention is to reduce the manufacturing cost by not using a special material, to have no limitation on the color of a visible image to be formed, to be excellent in concealment of an image pattern formed by infrared absorption, An object of the present invention is to provide an infrared-absorbing printed material which does not require forming a white concealing print layer even when an infrared-absorbing pattern is formed in a color image.

[0011]

In order to achieve the above-mentioned object, an infrared-absorbing printed material of the present invention comprises a substrate and at least one infrared absorbing layer formed on one side of the substrate. A layer having a camouflage pattern layer visible on visible light formed on one or the other surface of the infrared absorption layer, wherein the infrared absorption layer has a first infrared absorption characteristic. A region and the first region are formed at different positions;
A second region having a second infrared absorption characteristic or an infrared transmission characteristic different from the first infrared absorption characteristic, wherein the first region and the second region are visually recognized under visible light; Has a difficult color tone.

The printed matter of the present invention has a color tone that is difficult to see under visible light, but has an infrared absorption image formed by a first region and a second region having different infrared absorption characteristics. In addition, due to slight differences in printing density and printing accuracy,
Even if it is possible to easily recognize an infrared absorption image pattern even under visible light, by forming a camouflage pattern layer in addition to the first print layer and the second print layer, infrared light under visible light can be obtained. The concealment of the absorption image pattern can be improved.

Further, in order to achieve the above object, the infrared absorbing printed matter of the present invention has a substrate and at least two or more infrared absorbing layers formed on one side of the substrate. And
The infrared absorption layer is formed at a first region having a first infrared absorption characteristic and at a position different from the first region, and is provided at a second red region different from the first infrared absorption characteristic. A second region having an external absorption characteristic or an infrared transmission characteristic, wherein the first region and the second region each have two or more layers, and the first region is formed under visible light. And the second region has another color tone that is difficult to visually recognize, and one of the positive image and the negative image is formed differently from each other to form one visible image.

The above-mentioned printed matter of the present invention is a multicolor printed matter in which two or more colors of ink are printed, and the printing layer of each color contains an infrared absorbing pigment in the first region and the second region. By changing the amount, an infrared absorption image pattern that can detect an infrared absorption image pattern by an infrared camera or the like can be formed. The first region and the second region have different tones that are difficult to visually recognize under visible light, and the first region and the second region form one of a positive image and a negative image differently from each other. Thus, since one visible image is formed, it is possible to make it difficult to notice that the infrared absorption image pattern is hidden there.

Further, in order to achieve the above object, the infrared absorbing printed material of the present invention has a substrate and at least four or more infrared absorbing layers formed on one side of the substrate. And
The infrared absorption layer is formed at a first region having a first infrared absorption characteristic and at a position different from the first region, and is provided at a second red region different from the first infrared absorption characteristic. A second region having external absorption characteristics or infrared transmission characteristics, wherein the first region and the second region each include four or more layers including a cyan layer, a magenta layer, a yellow layer, and a black layer. The first region and the second region have different color tones that are difficult to visually recognize under visible light, and one of a positive image and a negative image is formed different from each other to form one visible image. Is formed.

The printed matter of the present invention can form a color image in four colors of cyan, magenta, yellow, and black, and each color layer is formed by a first region and a second region.
By changing the content of the infrared-absorbing pigment between the region and the region, an infrared-absorbing image pattern that can be detected by an infrared camera or the like can be formed. The first region and the second region have different tones that are difficult to visually recognize under visible light, and the first region and the second region form one of a positive image and a negative image differently from each other. Thus, since one visible image is formed, it is possible to make it difficult to notice that the infrared absorption image pattern is hidden there. Here, the four colors of cyan, magenta, yellow and black are in the range of colors used in normal process inks, and it is sufficient that a color image can be obtained by printing them in multiple colors. Is not limited.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

First Embodiment FIG. 1 is a cross-sectional view of an infrared-absorbing print of this embodiment.
A first print layer 21 is formed on a portion corresponding to the first print region A on the infrared reflective base 10, and a second print layer 22 is formed on a portion corresponding to the second print region B on the base 10. It has been done. Further, a first printing layer 21 and a second printing layer 22
A camouflage pattern layer 31 is formed on the upper layer. The first print layer 21 and the second print layer 22 have different infrared absorption characteristics. For example, the first print layer 21 contains an infrared absorbing material, and the second print layer 22 contains an infrared absorbing material. The composition should not be allowed to occur. However, the color tone difference is adjusted to be as small as possible so that visual distinction under visible light becomes difficult. The camouflage printing layer above the first printing layer 21 and the second printing layer 22 is obtained by printing a tint block or the like using, for example, an infrared transmitting ink.

In this embodiment, the color tone of the first print layer and the second print layer under visible light is not limited, and may be any color such as cyan, magenta, yellow, red, green, and blue. These infrared-absorbing printing layers are formed by adding an infrared-absorbing material to an infrared-transmitting ink for forming a normal visible image printing layer having no absorption in the infrared region. It can be formed by printing on a base material as a basic ink.

The infrared absorbing material is a substance that absorbs infrared light, and can be broadly classified into an infrared absorbing pigment and an infrared absorbing dye. Colorless infrared-absorbing pigments that absorb little or no visible light can be broadly divided into colored infrared-absorbing pigments having a certain absorption band in the visible region. Is excellent in the concealability of an image pattern formed by infrared absorption, it is preferable to use a colored infrared absorbing pigment for the purpose of reducing the production cost.

As the infrared absorbing pigment, transition metal compounds and complexes such as iron, copper, chromium, cobalt and nickel can be used. For example, a miroly blue pigment which is an iron complex (iron ferricyanide complex) is preferably used. In addition, the above compounds may be used alone or in combination of two or more.

As the infrared absorbing dye, dyes such as polymethine (cyanine dye), phthalocyanine, naphthoquinone, anthraquinone, dithiol, and triphenylmethane can be used.

In terms of light fastness (fading to infrared rays), infrared absorbing pigments are superior to infrared absorbing dyes, and it is preferable to use inorganic substances such as the above-mentioned metal pigments.

The content of the infrared-absorbing pigment with respect to the entire composition constituting the infrared-absorbing ink is set at 0 in order to improve both infrared absorption intensity and transferability (adhesion) to a printing substrate. 0.5-35% by weight is preferred. If the content is small, the infrared absorption intensity is not sufficient, and the image pattern formed by the infrared absorption may not be distinguished. Further, when the content is large, the printability deteriorates.

Further, it is necessary that the first print layer and the second print layer of the present embodiment have different infrared absorption characteristics. Specifically, it is necessary to change the concentration of the infrared absorption pigment contained in each print layer. Can be realized. Further, for example, the first print layer may contain an infrared absorbing material, and the second print layer may contain no infrared absorbing material.

Since commonly used coloring inks are infrared-transmitting, a desired color tone under visible light can be obtained by mixing these infrared-transmitting coloring inks with the above-mentioned infrared absorbing ink. Infrared absorbing ink can be produced. Further, the color difference is adjusted to be as small as possible so that the first print layer and the second print layer are difficult to visually recognize under visible light. Specifically, the color tone under visible light of the ink for the first printing layer and the ink for the second printing layer is adjusted by adjusting the type and concentration of the infrared-transmissive coloring ink to be mixed with the infrared-absorbing ink. Can be adjusted.

The following are specific examples of the infrared-transmitting pigments used in the infrared-transmitting colored inks. These infrared-transmitting pigments need only have no absorption in the infrared region. Process inks such as magenta, yellow and black can be used. In the following specific examples, parentheses C.I. I. Pigment (Color
Indicates the classification of Index Pigment.

Among the above-mentioned infrared transmitting color pigments, for example, the following pigments can be used as the yellow pigment. Fast Yellow G (Yellow-1), Fast Yellow 10G (Yellow-3), Disazo Yellow AAA
(Yellow-12), Disazo Yellow AAMX (Yellow-1
3), Disazo Yellow AAOT (Yellow-14), Disazo Yellow AAOA (Yellow-17), Disazo Yellow HR (Yellow-83).

As the magenta pigment among the above-mentioned infrared-transmissive coloring pigments, for example, the following can be used. Toluidine Red (Red-3), Chlorinated Rose Red (Red-4), Naphthol Carmine FB (Red-5), Naphthol Red M (Red-17), Brilliant Fast Scar Red (Red-22), Naphthol Red (Red) -twenty three),
Pyrazolone Red (Red-38), Barium Red 2B (Re
d-48: 1), calcium red 2B (Red-48: 2), strontium red (Red-48: 3), manganese red (Red-4
8: 4), Barium Risole Red (Red-49: 1), Lake Red C (Red-53: 1), Brilliant Carmine 6B (Re-
d-57: 1), Pigment Scar Red 3B Rake (Red-6
0: 1), Rake Bordeaux 10B (Red-63: 1), Ansosine 3B Lake (Red-66), Ansosine 5B Lake (Red-66)
67), rhodamine 6G lake (Red-81), eosin lake (Red-90), naphthol red FGR (Red-112).

Among the infrared-transmitting coloring pigments described above, as the cyan pigment, for example, the following can be used. Victoria Pure Blue BO Lake (Blue-1),
Basic Blue 5B Lake (Blue-3), Basic Blue 6G Lake (Blue-9), Phthalocyanine Blue (α
Type, unstable form) (Blue-15: 1), phthalocyanine blue (β-type, non-crystalline) (Blue-15: 3), phthalocyanine blue (β-type, non-crystalline, non-assembled) (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), Reflex Blue 2G (Blue-56), Reflex Blue R
(Blue-61).

Among the above-mentioned infrared-transmissive coloring pigments, for example, the following pigments can be used as black pigments. Format black (mixed pigment of yellow, magenta and cyan pigments), aniline black (Black-1).

Among the above-mentioned infrared-transmissive coloring pigments, for example, the following can be used as the white pigment (enrichment pigment). Zinc flower (White-4), titanium oxide (Whit
e-6), calcium carbonate (White-18), clay (White-1)
9), barium sulfate (White-21), alumina white (W
hite-24).

The vehicle of the infrared-absorbing ink for forming the infrared-absorbing printing layer of the present invention includes an infrared wavelength region,
Further, those having substantially no absorption band in the wavelength region of visible light are preferable. Examples of the binder resin as a main component of the vehicle include polyethylene-based [polyethylene (PE), ethylene-vinyl acetate copolymer (EVA),
Vinyl chloride-vinyl acetate copolymer], polypropylene (PP), vinyl type (polyvinyl chloride (PVC), polyvinyl butyral (PVB), polyvinyl alcohol (PVA), polyvinylidene chloride (PVdC), polyvinyl acetate (PVAc) , Polyvinyl formal (PV
F)], polystyrene [polystyrene (PS), styrene-acrylonitrile copolymer (AS), acrylonitrile-butadiene-styrene copolymer (ABS)],
Acrylic [polymethyl methacrylate (PMMA),
MMA-styrene copolymer], polycarbonate (P
C), cellulose type [ethyl cellulose (EC), cellulose acetate (CA), propyl cellulose (CP), acetic acid / cellulose acetate (CAB), cellulose nitrate (C
N)], fluorine-based [polychlorofluoroethylene (PC
TFE), polytetrafluoroethylene (PTFE),
Tetrafluoroethylene-hexafluoroethylene copolymer (FEP), polyvinylidene fluoride (PVd
F)], urethane-based (PU), nylon-based [type 6,
Type 66, type 610, type 11], polyester (alkyd) type [polyethylene terephthalate (P
ET), polybutylene terephthalate (PBT), polycyclohexane terephthalate (PCT)], and a thermoplastic resin such as a novolak phenol resin. In addition, thermosetting resins such as resol type phenol resin, urea resin, melamine resin, polyurethane resin, epoxy, unsaturated polyester, protein, rubber,
Natural resins such as shellac, copal, starch, and rosin can also be used.

Furthermore, these resins can be emulsions for water-based paints. Examples of emulsions for aqueous paints include vinyl acetate (homo) emulsion, vinyl acetate-acrylate copolymer emulsion, and vinyl acetate-ethylene copolymer resin emulsion (E).
VA emulsion), vinyl acetate-vinyl versatate copolymer resin emulsion, vinyl acetate-polyvinyl alcohol copolymer resin emulsion, vinyl acetate-vinyl chloride copolymer resin emulsion, acrylic emulsion, acrylic silicone emulsion, styrene-acryl copolymer resin emulsion, Polystyrene emulsion, urethane emulsion, chlorinated polyolefin emulsion,
Epoxy-acryl dispersion, SBR latex, or the like can be used.

Further, if necessary, a plasticizer for stabilizing the flexibility and strength of the print film and a solvent for adjusting the viscosity and drying may be added to the vehicle. As the solvent, a low-boiling solvent having a boiling point of about 100 ° C. and a high-boiling petroleum solvent having a boiling point of 250 ° C. or more can be used depending on the printing method. As a solvent having a low boiling point, for example, alkylbenzene or the like can be used.

Further, auxiliary agents such as various reactants for improving drying, viscosity and dispersibility can be appropriately added.
The auxiliary agent is used to adjust the performance of the ink. For example, a compound that improves the friction resistance of the ink surface after drying, a dryer that promotes the drying of the ink, and the like can be used.

A photopolymerization-curable or electron beam-curable resin that does not use a solvent can also be used as a binder resin that is a main component of the vehicle. For example, there is an acrylic resin, and specifically, the followings can be used as those commercially available as acrylic monomers.

Examples of the monofunctional acrylate include 2-ethylhexyl acrylate, 2-ethylhexyl EO adduct acrylate, ethoxydiethylene glycol acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, and caprolactone adduct of 2-hydroxyethyl acrylate. Phenoxyethyl acrylate, phenoxydiethylene glycol acrylate, nonylphenol EO adduct acrylate,
Nonylphenol EO adduct caprolactone adduct acrylate, 2-hydroxy-3-phenoxypropyl acrylate, tetrahydrofurfuryl acrylate, furfuryl alcohol caprolactone adduct acrylate, acryloylmorpholine, dicyclopentenyl acrylate, dicyclopentanyl acrylate,
Dicyclopentenyloxyethyl acrylate, isobornia acrylate, acrylate of caprolactone adduct of 4,4-dimethyl-1,3-dioxane, acrylate of caprolactone adduct of 3-methyl-5,5-dimethyl1,3-dioxane Etc. can be used.

Examples of the polyfunctional acrylate include hexanediol diacrylate, neopentyl glycol diacrylate, polyethylene glycol diacrylate, tripropylene glycol diacrylate, neopentyl glycol hydroxypivalate diacrylate, and neopentyl glycol hydroxypivalate. Diacrylate of caprolactone adduct of
Acrylic acid adduct of 1,6-hexanediol diglycidyl ether, diacrylate of acetal compound of hydroxypivalaldehyde and trimethylolpropane, 2,2-bis [4- (acryloyloxydiethoxy) phenyl] propane, 2,2-bis [4- (acryloyloxydiethoxy) phenyl] methane, diacrylate of hydrogenated bisphenol A ethylene oxide adduct, tricyclodecane dimethanol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, Trimethylolpropane propylene oxide adduct triacrylate, glycerin propylene oxide adduct triacrylate, dipentaerythritol hexaacrylate / pentaacrylate mixture, dipenta Lower fatty acid and esters of acrylic acid Risuritoru, acrylate caprolactone adduct of dipentaerythritol, tris (acryloyloxyethyl) isocyanurate, and the like can be used 2-acryloyloxyethyl phosphate.

The inks composed of these resins are solvent-free and have a composition that causes a chain polymerization reaction by irradiation of electromagnetic waves or electron beams. Among them, the ultraviolet irradiation type requires a photopolymerization initiator, A polymerization inhibitor, a chain transfer agent and the like may be added as a sensitizer and an auxiliary depending on the above.

As the photopolymerization initiator, 1) direct photolysis type such as arylalkyl ketone, oxime ketone, acylphosphine oxide, etc. 2) radical polymerization reaction type such as benzophenone derivative, thioxanthone derivative, etc. 3) cationic polymerization reaction As the mold, an aryldiazonium salt, an aryliodonium salt, an arylsulfonium salt, an arylacetophenone salt, or the like can be used. In addition, 4) an energy transfer type, 5) a photo redox type, 6) an electron transfer type, or the like can be used. be able to. For the electron beam curing type, a resin similar to that of the above-described ultraviolet irradiation type may be used, and a photopolymerization initiator may not be required, and various assistants may be added as needed.

As a method for forming an infrared-absorbing printing layer containing an infrared-absorbing pigment, various conventionally known methods can be used. For example, there are an intaglio printing method such as a relief printing method and a gravure method, a lithographic printing method of an offset method, and a screen stencil (stencil). In addition, thermal transfer methods (for example, JP-A-61-213195, JP-A-59-54598, and JP-A-62-111800)
JP-A-3-187786) and an ink-jet method (for example, see JP-A-3-81376).

In this embodiment, a camouflage pattern layer such as a tint block made of visible ink as shown in FIG. 2 is provided to make it difficult to visually recognize an image formed as an infrared absorption image under visible light. The camouflage pattern is preferably as random as possible. As ink for camouflage pattern layer,
Infrared transmitting inks can be used, and one of the above infrared transmitting inks can be used as it is.

In addition to the camouflage pattern described above,
Underlay or background on the lower or upper layer of the infrared absorbing print layer
As the printing layer or the like, a visible image layer composed of a single color or multiple colors may be formed, and can be formed by a known printing method using a known coloring paint or ink. For example, a coloring paint or ink can be obtained by adding various pigments to a binder according to the color to be colored. As the binder, those exemplified as the resin constituting the vehicle component of the infrared absorbing ink for the infrared absorbing printing layer described above can be used. Colored paint or ink
If necessary, a plasticizer, a stabilizer, a wax, a desiccant, a drying aid, a curing agent, a thickener, a dispersant, a solvent or a diluent can be added. Examples of the printing method include a printing method such as a usual gravure method, a roll method, a knife edge method, and an offset method, and a transfer method. When using the transfer method,
For the purpose of improving the adhesiveness of the transfer pattern, it is preferable to coat the appropriate resin in advance to form a smooth layer, thereby smoothing the transfer surface.

In the above method, a first printing layer is formed on a portion corresponding to a first printing region on a substrate, a second printing layer is formed on a portion corresponding to a second printing region, and a camouflage pattern layer is formed. As the substrate used in the present invention, a conventionally known substrate can be used. Further, an intermediate layer and a protective layer not shown in FIG. 1 may be formed, and a conventionally known layer can be used for the formation.

As the substrate, paper such as high-quality paper, OCR paper, art paper, coated paper, mirror coated paper, condenser paper, paraffin paper, polyester, polypropylene, cellophane, acetate, vinyl chloride, polyvinyl chloride, polycarbonate, acrylic, etc. Plastic film, copper,
Metals such as aluminum can be used alone or in combination as a composite. In order to correctly detect the infrared absorption image pattern, it is preferable that the material reflects 80% or more of infrared light. The material can be appropriately selected from the above materials in consideration of physical properties required for the substrate, for example, strength, rigidity, concealing property, light opacity and the like.

As the intermediate layer, those having high transmittance with respect to visible light and infrared light are preferable. As the constituent components, those exemplified as the resin constituting the vehicle component of the infrared absorbing ink for the infrared absorbing printing layer described above can be used. In particular, a photopolymerization-curing type or an electron beam-curing type which does not use a solvent is preferable. This can be formed using the above-mentioned acrylic monomer. In addition, you may add a solvent and an auxiliary agent as needed.

The protective layer preferably has high transparency to visible light and infrared light, and can be formed by overlamination or overcoating. The overlaminate can be formed by laminating a transparent film such as polyethylene terephthalate, polyvinyl chloride, polyethylene, or polypropylene by a conventional method.

As the overcoat, those exemplified as the resin constituting the vehicle component of the infrared absorbing ink of the infrared absorbing printing layer described above can be used. In particular, a photopolymerization-curing type or an electron beam-curing type without using a solvent is preferable, and examples thereof include an acrylic resin. This can be formed using the above-mentioned acrylic monomer.
As described above, additives such as a polymerization initiator are contained, and those additives having high transparency to visible light and infrared light are appropriately selected. Further, an OP layer may be formed on the outermost surface by offset printing of a medium or the like.

An example of the present embodiment will be described below with reference to the drawings. Example 1 Colored infrared absorbing ink A1 and infrared transmitting ink T1,
And an infrared-transparent ink C1 for a camouflage printing layer were produced with the compositions shown in the following table, respectively.

[0051]

[Table 1]

[0052]

[Table 2]

[0053]

[Table 3]

In Table 1, Millory Blue Base is an infrared absorbing ink having the composition shown in Table 4 below.

[0055]

[Table 4]

The positive pattern shown in FIG. 3 is offset-printed on the base material 10 made of high-quality paper (90 kg / 46 format) using the above-mentioned colored infrared absorbing ink A1.
And Next, the negative pattern of the background portion in FIG. 3 was offset-printed with the infrared-transmitting ink T1 having substantially the same color as the second print layer 22. First print layer 21 and second print layer 22
Is as shown in FIG. 4, and the first printed layer 21 on which the infrared absorbing ink A1 is printed is in the infrared region more than the second printed layer 22 on which the infrared transmitting ink T1 is printed. It has strong absorption, for example, the difference in reflectance around 830 nm is about 40%. In the visible region, both had very similar spectral shapes. Therefore, this infrared-absorbing image pattern printed material could be printed so as to be a substantially uniform color under visible light, but due to slight differences in printing density and printing accuracy, the infrared-absorbing image pattern could easily be printed under visible light. It was possible to recognize.

Next, in order to make it difficult to recognize the infrared-absorbing image pattern under visible light, the first printing layer 21 and the second
A camouflage pattern layer 31 shown in FIG. 2 was formed on the print layer 22 by offset printing. In the printed matter obtained as a result, it was difficult to visually recognize the infrared absorption image pattern under visible light.

The infrared absorption image of the above infrared absorption printed matter is
Although it could not be visually recognized under visible light, the infrared absorption portion (positive pattern of FIG. 3 composed of the first print layer) was black with good contrast using the infrared camera shown in FIG. In the infrared transmitting portion (the negative pattern of FIG. 3 composed of the second print layer), the pattern could be recognized as white. Here, the infrared camera shown in FIG. 5 uses a small LED (peak emission wavelength 830 nm) as a light source, and a camera lens is provided with a visible light cut filter. When the printed matter is irradiated with infrared light, the intensity of the reflected light is detected by the camera,
Binarization is performed by converting an optical signal into an electric signal, and the pattern is converted into a black-and-white contrast pattern in a small CRT (SON).
Y VIS-4000 / 4000E).

The above-mentioned infrared absorbing printed matter does not use a special material such as a transparent infrared absorbing pigment, so that the manufacturing cost is reduced, and the color of a visible image formed by mixing various coloring pigments is not limited. And excellent in concealment of an image pattern formed by infrared absorption.

Second Embodiment FIG. 6 is a cross-sectional view of an infrared-absorbing print of this embodiment.
In the present embodiment, cyan, magenta, yellow,
A color image is formed by a subtractive color mixture method using a combination of the four inks in the same manner as a normal color print using black four-color inks. All the printed portions that appear black when viewed under visible light are shown. Actually, it can have regions exhibiting various colors formed by the combination of the presence or absence of each color ink.

In FIG. 6, a first print layer 21 is formed on a portion corresponding to the first print region A on the infrared reflective base 10, and a portion corresponding to the second print region B on the base 10 is provided. The second print layer 22 has been formed. First printing layer 2
The first and second print layers 22 have different infrared absorption characteristics. For example, the first print layer 21 contains an infrared absorbing material, and the second print layer 22 has a composition that does not contain an infrared absorbing material. . The first print layer 21 and the second print layer 22 are mixed with an infrared-transmissive pigment used in a normal printed matter and printed, for example, as an ink having a cyan color visually under visible light. The type and density of the mixed color infrared transmitting pigments are adjusted so as to make the difference in color tone as small as possible so that visual distinction under visible light becomes difficult.

The third print layer 23 is formed on the first print layer 21.
Is formed, and a fourth print layer 24 is formed on the second print layer 22. Similarly to the relationship between the first print layer 21 and the second print layer, the third print layer 23 and the fourth print layer 24 also have different infrared absorption characteristics. For example, the third print layer 23 contains an infrared absorbing material. The fourth print layer 24 has a composition that does not contain an infrared absorbing material, and is mixed with an infrared transmissive pigment and printed, for example, as an ink having a magenta color visually under visible light. The type and density of the mixed color infrared transmitting pigments are adjusted so as to make the difference in color tone as small as possible so that visual distinction under visible light becomes difficult.

The fifth print layer 25 is formed on the third print layer 23.
Is formed, and a sixth print layer 26 is formed on the fourth print layer 24. Similarly to the relationship between the first print layer 21 and the second print layer, the fifth print layer 25 and the sixth print layer 26 also have different infrared absorption characteristics. For example, the fifth print layer 25 may contain an infrared absorbing material. The sixth print layer 26 has a composition that does not contain an infrared absorbing material, is mixed with an infrared transmissive pigment, and printed as an ink having a yellow color, for example, under visual light, and The type and density of the mixed color infrared transmitting pigments are adjusted so as to make the difference in color tone as small as possible so that visual distinction under visible light becomes difficult.

The seventh print layer 27 is formed on the fifth print layer 25.
Is formed, and an eighth printed layer 28 is formed on the sixth printed layer 26. Similarly to the relationship between the first print layer 21 and the second print layer, the seventh print layer 27 and the eighth print layer 28 also have different infrared absorption characteristics. For example, the seventh print layer 27 contains an infrared absorbing material. The eighth print layer 28 has a composition not containing an infrared absorbing material, and is mixed with an infrared transmissive pigment and printed, for example, as an ink having a black color visually under visible light. The type and density of the mixed color infrared transmitting pigments are adjusted so as to make the difference in color tone as small as possible so that visual distinction under visible light becomes difficult.

As described above, the first printing area A on the infrared-reflective substrate 10 has the first printing layer 21 for cyan, the third printing layer 23 for magenta, and the fifth printing layer for yellow. 25
And a seventh printing layer 27 of black color is formed,
In the print area B, a second print layer 22 of cyan, a fourth print layer 24 of magenta, a sixth print layer 26 of yellow, and an eighth print layer 28 of black are formed. Area A
Since the inks with different infrared absorption characteristics are used in the first and second printing regions B and B, the infrared absorption characteristics can be changed between the first printing region A and the second printing region B where the inks are laminated. Thereby, an infrared absorption image can be formed.

Further, the first print area A and the second print area
In the printing region B, the infrared absorption characteristics can be made different by changing the concentration of the infrared absorbing pigment contained in each printing layer for each color. Further, for example, the first print layer, the third print layer, the fifth print layer, and the seventh print layer contain an infrared absorbing material, and the second print layer, the fourth print layer, the sixth print layer, and the eighth print layer. The printing layer may have a composition that does not contain an infrared absorbing material.

The first print area A and the second print area B form either one of a positive image and a negative image different from each other, and one color image is formed by both images.
Therefore, it is possible to make it difficult to notice that the infrared absorption image pattern is hidden there.

In order to form the above-mentioned infrared absorbing printed matter, the inks of the respective colors of cyan, magenta, yellow and black described in the first embodiment and other materials can be used. Here, the four colors of cyan, magenta, yellow and black only need to be in the range of colors used in normal process inks, and if a color image can be obtained by printing them in multiple colors, the absorption band in the visible region thereof can be reduced. position,
The width or shape is not limited. Further, an intermediate layer, a protective layer, and the like not shown in FIG. 6 may be formed. In that case, the materials described in the first embodiment can be used.

Hereinafter, examples of the present embodiment will be described with reference to the drawings. Example 2 Cyan infrared absorbing ink A2 and infrared transmitting ink T
2. Magenta infrared absorbing ink A3 and infrared transmitting ink T3, yellow infrared absorbing ink A4 and infrared transmitting ink T4, black infrared absorbing ink A5 and infrared transmitting Inks T5 were each produced with the composition shown in the table below.

[0070]

[Table 5]

[0071]

[Table 6]

[0072]

[Table 7]

[0073]

[Table 8]

In Tables 5 to 8, Millory Blue Base is the infrared absorbing pigment described in Example 1. FIG. 7 shows a spectral reflection spectrum of a printing layer obtained by printing the cyan infrared absorbing ink A2 and the infrared transmitting ink T2. The printing layer on which the infrared absorbing ink A2 is printed has a stronger absorption in the infrared region than the printing layer on which the infrared transmitting ink T2 is printed. For example, the difference in reflectance around 830 nm is about 2
5%. In the visible region, both printed layers had almost identical spectral shapes.

FIG. 8 shows the spectral reflection spectrum of the printing layer obtained by printing the magenta infrared absorbing ink A3 and the infrared transmitting ink T3. The printing layer on which the infrared absorbing ink A3 is printed has a stronger absorption in the infrared region than the printing layer on which the infrared transmitting ink T3 is printed.
The difference in reflectance near m was about 30%. In the visible region, both printed layers had almost identical spectral shapes.

FIG. 9 shows the spectral reflection spectrum of the printing layer obtained by printing the yellow infrared absorbing ink A4 and the infrared transmitting ink T4. The printing layer on which the infrared absorbing ink A4 is printed has a stronger absorption in the infrared region than the printing layer on which the infrared transmitting ink T4 is printed.
The difference in reflectance near m was about 30%. In the visible region, both printed layers had almost identical spectral shapes.

FIG. 10 shows the spectral reflection spectrum of a printing layer obtained by printing the black infrared absorbing ink A5 and the infrared transmitting ink T5. The printing layer on which the infrared absorbing ink A5 is printed has a stronger absorption in the infrared region than the printing layer on which the infrared transmitting ink T5 is printed, for example, 830.
The difference in reflectance near nm was about 25%. In the visible region, both printed layers had almost identical spectral shapes.

Using the cyan infrared absorbing ink A2 described above, a white PET base material (manufactured by Panac, E-22, thickness 1)
The positive pattern shown in FIG. Next, the negative pattern of the background portion in FIG. At this time, when the first print layer 21 and the second print layer 22 are printed, a cyan positive pattern and a negative pattern are printed,
A single cyan image could be formed by combining the positive and negative patterns.

Next, the positive pattern shown in FIG. 3 was offset-printed on the first printing layer 21 using the magenta infrared absorbing ink A3 to form a third printing layer 23.
Next, the negative pattern of the background portion in FIG. 3 was offset-printed on the upper layer of the second print layer 22 with the magenta infrared-transmitting ink T3 to form a fourth print layer 24.

Next, the positive pattern shown in FIG. 3 was offset-printed on the upper layer of the third print layer 23 using the yellow infrared absorbing ink A4 to form a fifth print layer 25.
Next, a negative pattern of the background portion of FIG. 3 was offset-printed on the upper layer of the fourth print layer 24 with the infrared-transparent ink T4 of yellow color to form a sixth print layer 26.

Next, the positive pattern shown in FIG. 3 was offset-printed on the upper layer of the fifth printing layer 25 using the black infrared absorbing ink A5 to form a seventh printing layer 27.
Next, the negative pattern of the background portion in FIG. 3 was offset-printed on the upper layer of the sixth printing layer 26 with the infrared transmitting ink T5 of black color to form an eighth printing layer 28.

As described above, the first print area 21, the third print layer 23, the fifth print layer 25, and the seventh print layer 27 of FIG. A color image having a positive pattern is formed, and a region B on the substrate 10
The second print layer 22, the fourth print layer 24, the sixth print layer 26
A color image having the negative pattern of FIG. 3 is formed, and the color image of the first print area A and the color image of the second print area B are combined to form one color image. Was completed. It is difficult to visually recognize the infrared-absorbing image pattern of the thus-obtained infrared-absorbing printed material under visible light, and a printed material substantially similar to ordinary process color printing can be produced visually.

On the other hand, in the same manner as in Example 1, the infrared absorbing printed matter described above was obtained by using the infrared camera shown in FIG. The positive pattern was recognized as black, and the infrared transmitting portion (negative pattern in FIG. 3 formed in the second printing area B) was recognized as white.

The above-mentioned infrared absorbing printed matter does not use a special material such as a transparent infrared absorbing pigment, so that the production cost is reduced, and the color of a visible image formed by mixing various coloring pigments is limited. In addition, the opacity of the image pattern formed by infrared absorption is excellent, and the infrared absorption pattern can be formed in a color image without separately forming a white opaque print layer.

The present invention is not limited to the above embodiment.
For example, the contrast of the infrared absorbing image is given by the printing layer containing the infrared absorbing pigment and the printing layer not containing the infrared absorbing pigment. However, the contrast can be given by giving a difference in the concentration of the infrared absorbing pigment. For multi-color printing, use cyan,
Magenta, yellow, and black are used.
Multicolor printing may be performed by selecting two or more of these colors, or multi-layer printing of two or more other colors may be performed. Further, a camouflage pattern layer may be further provided in addition to the multicolor printing. In addition, various changes can be made without departing from the spirit of the present invention.

[0086]

According to the present invention, the production cost is reduced by using no special material, the color of the visible image to be formed is not limited, and the image pattern formed by infrared absorption is excellent in concealment. Infrared absorbing printed matter can be provided.

According to the present invention, the production cost is reduced by using no special material, the color of a visible image to be formed is not limited, and the image pattern formed by infrared absorption is excellent in concealment. It is possible to provide an infrared-absorbing printed material capable of forming an infrared-absorbing pattern in a multicolor printed image without separately forming a white concealing printing layer.

According to the present invention, the production cost is reduced by using no special material, the color of the visible image to be formed is not limited, and the image pattern formed by infrared absorption is excellent in concealment. It is possible to provide an infrared-absorbing printed material capable of forming an infrared-absorbing pattern in a color image without separately forming a white concealing printing layer.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of an infrared-absorbing printed matter of the present invention.

FIG. 2 is an example of a camouflage pattern preferably used for the infrared absorbing printed matter of the present invention.

FIG. 3 shows an image pattern formed by infrared absorption in Examples 1 and 2 of the infrared absorbing printed matter of the present invention.

FIG. 4 shows an infrared absorbing ink (A1) and an infrared transmitting ink (T) of Example 1 of the infrared absorbing printed matter of the present invention.
1 shows the shape of the spectral reflection spectrum of a printed matter obtained by printing using 1).

FIG. 5 is a schematic diagram of an infrared camera for recognizing an infrared absorption image formed on the infrared absorption printed material of the present invention.

FIG. 6 is a sectional view showing a second embodiment of the infrared absorbing printed matter of the present invention.

FIG. 7 is a spectral reflection spectrum of a printed material obtained by printing using the cyan infrared absorbing ink (A2) and the infrared transmitting ink (T2) of Example 2 of the present invention. .

FIG. 8 is a spectral reflection spectrum of a printed material obtained by printing using the magenta infrared absorbing ink (A3) and the infrared transmitting ink (T3) of Example 2 of the present invention. .

FIG. 9 is a spectral reflection spectrum of a printed material obtained by printing using the yellow infrared absorbing ink (A4) and the infrared transmitting ink (T4) of Example 2 of the present invention. .

FIG. 10 shows a black infrared absorbing ink (A5) and an infrared transmitting ink (T) of Example 2 of the present invention.
5 is a spectral reflection spectrum of a printed matter obtained by printing using 5).

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Base material, 21 ... 1st printing layer, 22 ... 2nd printing layer, 2
3: Third print layer, 24: fourth print layer, 25: fifth print layer, 26: sixth print layer, 27: seventh print layer, 28: eighth
Print layer, 31: camouflage pattern layer, A: first print area, B: second print area.

Claims (5)

[Claims] 1. A substrate, at least one or more infrared absorbing layers formed on one surface of the substrate, and visible light formed on one or the other surface of the infrared absorbing layer. The infrared absorption layer is formed at a first region having a first infrared absorption characteristic and at a position different from the first region, and the infrared absorption layer is formed at a position different from the first region. A second region having a second infrared absorption characteristic or an infrared transmission characteristic different from the external absorption characteristic, wherein the first region and the second region have a color tone that is difficult to see under visible light. Infrared absorbing printed matter. 2. A base material, and at least two or more infrared absorption layers formed on one surface side of the base material, wherein the infrared absorption layer has a first infrared absorption characteristic. And a second region formed at a position different from the first region and having a second infrared absorption characteristic or an infrared transmission characteristic different from the first infrared absorption characteristic. The first region and the second region each have two or more layers, and have a color tone in which the first region and the second region are difficult to visually recognize under visible light. One of the positive image and the negative image is formed differently from each other.
Infrared absorbing printed matter forming a visible image. 3. A base material, and at least four or more infrared absorption layers formed on one surface side of the base material, wherein the infrared absorption layer has a first infrared absorption characteristic. And a second region formed at a position different from the first region and having a second infrared absorption characteristic or an infrared transmission characteristic different from the first infrared absorption characteristic. The first region and the second region each have four or more layers including a cyan layer, a magenta layer, a yellow layer, and a black layer, and the first region and the second region under visible light. An infrared-absorbing printed matter having another color tone that makes it difficult to visually recognize the second area, and forms one visible image by forming either the positive image or the negative image different from each other. 4. The red light according to claim 1, wherein the infrared absorbing layer has an infrared absorbing property by containing an inorganic infrared absorbing pigment containing a transition metal compound and a complex. Outside printed matter. 5. The infrared absorbing printed matter according to claim 1, wherein the infrared absorbing layer has an infrared absorbing property by containing an iron complex.