Forgery preventing printed matter and ink composition

Abstract

To provide a forgery preventing printed matter and an ink composition having a bright hue in a visible wavelength region, capable of reducing a hue limit in design, having a wide hue reproduction range, having high forgery resistance, and having a printing region exhibiting a specific spectral reflectance formed by simple means.SOLUTION: A forgery preventing printed matter according to the present invention is a forgery preventing printed matter having a printed portion formed on a substrate, wherein the printed portion has a maximum reflectivity of 40% or more in a visible-wavelength region and an average spectral reflectance of 85% or more in a wavelength region 900 nm to 950 nm; an average spectral reflectance in a wavelength region 830 nm to 850 nm is lower than an average spectral reflectance in the wavelength region 900 nm to 950 nm by 30% or more; and the forgery preventing printed matter comprises a printing region formed by using an ink composition including two or more kinds of colorants.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an anti-counterfeiting printed matter and an ink composition. More specifically, the present invention relates to an anti-counterfeiting printed matter having a printed area with a maximum reflectance of 40% or more in the visible wavelength range and an average spectral reflectance of 85% or more in the wavelength range of 900 nm to 950 nm, and an ink composition for forming such a printed area. [Background technology]

[0002] It is known that when a printing area is formed by preparing a general printing ink, the printing area absorbs light in the visible wavelength region and transmits light in the infrared wavelength region. Therefore, when preparing an anti-counterfeiting printed matter, a printing area having a function of absorbing light in the infrared wavelength region is formed, and the printing area is irradiated with light in the infrared wavelength region to discriminate between genuine and counterfeit. As the printing ink used to form the printing area having a function of absorbing light in the infrared wavelength region, a printing ink containing carbon black (CI Pigment Black 7) or ITO, which is a material that absorbs light in the near-infrared wavelength region, is used.

[0003] On the other hand, with the development of printing equipment and digital devices such as printers, color copiers, and scanners, it has become easy to produce elaborate copies of anti-counterfeit printed matter of valuable printed matter, etc. For this reason, anti-counterfeit printed matter with enhanced resistance to counterfeiting through various anti-counterfeiting technologies has been proposed.

[0004] Patent Document 1 discloses an anti-counterfeiting printed matter in which an image is formed on at least a part of a base material by a first printed area printed with a first ink and a second printed area printed with a second ink, the first printed area and the second printed area being visually recognized as the same color in the visible light range, the first printed area having a reflectance characteristic of 80% or more in the wavelength range of 780 to 1000 nm, and the second printed area having a reflectance characteristic of 20 to 60% in the wavelength range of 780 to 830 nm and a reflectance characteristic of 80% or more in the wavelength range of 900 to 1000 nm, and the first printed area and the second printed area being characterized in that only the second printed area is visually recognized under a first wavelength in the infrared range, and neither the first printed area nor the second printed area is visually recognized under a second wavelength different from the first wavelength. This anti-counterfeiting printed matter (i) differs from known technologies such as infrared-transmitting and absorbing pair inks or metallic inks in that it prevents counterfeiting by changing the spectral reflectance only in a specific wavelength range, thereby providing a printed matter with high anti-counterfeiting resistance; (ii) it can reproduce the characteristics of the spectral reflectance in the infrared range by selecting general coloring pigments without using materials with high black density such as carbon black, thereby providing a printed matter with high design freedom; and (iii) by using pair inks to produce printed matter, it is possible to visually recognize different infrared images for each of two specific wavelengths in the near-infrared light range and determine whether it is genuine or not, thereby enabling easy authenticity determination.

[0005] Patent Document 2 discloses a thermal transfer material having a thermally meltable ink layer formed on a substrate, the thermally meltable ink layer being a layer containing a near-infrared absorbing agent (excluding carbon black), the near-infrared absorbing agent being a phthalocyanine-based compound that absorbs light at a wavelength of 700 nm, and the near-infrared absorbing agent being one or more compounds selected from the group consisting of copper phthalocyanine bromide, cobalt phthalocyanine, halogenated cobalt phthalocyanine, titanium phthalocyanine, halogenated titanium phthalocyanine, lead phthalocyanine, halogenated lead phthalocyanine, aluminum phthalocyanine, halogenated aluminum phthalocyanine, monochloroaluminum phthalocyanine, and monochloroaluminum halogenated phthalocyanine. A record using this thermal transfer material can be observed as a normal record with the naked eye, but can be identified as a special record using an infrared absorption detector, and is therefore effective in verifying and preventing tampering with various products, securities, bankbooks, certification cards, etc. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2011-178009 A [Patent Document 2] Japanese Patent Application Publication No. 1-30788 Summary of the Invention [Problem to be solved by the invention]

[0007] Many of the anti-counterfeiting printed matters known so far are printed using an ink composition containing carbon black that absorbs in the infrared region. Anti-counterfeiting printed matters formed from such ink compositions absorb in the entire wavelength range from the visible wavelength range to the near infrared range, so that when the printed layer is visually observed in the visible wavelength range, it tends to have a dark hue, which imposes design restrictions, and since it always absorbs at any wavelength in the infrared range, it is easy to distinguish between genuine and counterfeit. Furthermore, carbon black is easily available as a commercial product, and since it is easy to produce printed matters, its counterfeit resistance is becoming weaker.

[0008] One of the problems that the present invention aims to solve is to provide an anti-counterfeit printed matter having a printed area that has a bright hue in the visible wavelength range, allows for reduced hue restrictions during design, has a wide hue reproduction range, is highly resistant to counterfeiting, and exhibits a specific spectral reflectance formed by simple means.

[0009] One of the problems that the present invention aims to solve is to provide an ink composition that has a bright hue in the visible wavelength range, can reduce hue restrictions at the time of design, has a wide hue reproduction range, is highly resistant to counterfeiting, and can form a printed area showing a specific spectral reflectance by simple means. [Means for solving the problem]

[0010] As a result of intensive research into solving the above-mentioned problems, the present inventors found that the above-mentioned problems can be solved by (i) an anti-counterfeit printed matter having a printed area P1 in which the maximum reflectance in the visible wavelength region is in a specific range, the average spectral reflectance in the specific wavelength region is in a specific range, and the average spectral reflectance in the specific wavelength region has a specific relationship, and (ii) an ink composition that forms a printed area P3 in which the maximum reflectance in the visible wavelength region is in a specific range, the average spectral reflectance in the specific wavelength region is in a specific range, and the average spectral reflectance in the specific wavelength region has a specific relationship, and thus completed the present invention.

[0011] The present invention relates to the following anti-counterfeit printed matter and ink composition. [Item 1] An anti-counterfeiting printed matter having a printed portion formed on a substrate, The printing unit includes: The maximum reflectance in the visible wavelength range is 40% or more, The average spectral reflectance in the wavelength range of 900 nm to 950 nm is 85% or more, A printed area has an average spectral reflectance in the wavelength range of 830 nm to 850 nm that is 30% or more lower than the average spectral reflectance in the wavelength range of 900 nm to 950 nm. The anti-counterfeiting printed matter. [Item 2] An ink composition for printing the anti-counterfeit printed matter according to item 1, The ink composition includes at least one colorant containing a titanyl phthalocyanine pigment. [Item 3] The ink composition according to item 2, wherein the content of the titanyl phthalocyanine pigment is 0.3% by mass or more and 25% by mass or less based on the total amount of the ink composition. Effect of the Invention

[0012] The present invention provides an anti-counterfeiting printed matter CP having a printed area P1 that has a bright hue in the visible wavelength range, allows for reduced hue restrictions during design, has a wide hue reproduction range, is highly resistant to counterfeiting, and exhibits a specific spectral reflectance formed by simple means.

[0013] The present invention provides an ink composition that has a bright hue in the visible wavelength range, reduces hue restrictions during design, has a wide hue reproduction range, is highly resistant to counterfeiting, and can form a printing area P3 (printing area 1) that exhibits a specific spectral reflectance by simple means. [Brief description of the drawings]

[0014] [Figure 1]FIG. 2 shows the visibility of the anti-counterfeit printed matter CP of Example 1, which is one embodiment of the present invention, in the visible wavelength range, at a wavelength of 830 nm using an infrared monitor, and at a wavelength of 940 nm using an infrared monitor. [Diagram 2] FIG. 1 shows the spectral reflectance at wavelengths of 400 nm to 1000 nm for a printed area P1 printed with blue ink, a printed area P1 printed with red ink, and a printed area P1 printed with yellow ink used when printing an anti-counterfeit printed matter CP of Example 1, which is one embodiment of the present invention. [Diagram 3] FIG. 13 is a diagram showing the visibility of the anti-counterfeit printed matter of Comparative Example 1 in the visible wavelength region, at a wavelength of 830 nm using an infrared monitor, and at a wavelength of 940 nm using an infrared monitor. [Figure 4] FIG. 13 is a graph showing the spectral reflectance in the wavelength range of 400 nm to 1000 nm for the area printed with the blue ink, the area printed with the red ink, and the area printed with the yellow ink used in printing the anti-counterfeit printed matter of Comparative Example 1. [Diagram 5] FIG. 13 is a diagram showing the visibility in the visible wavelength region, the visibility at a wavelength of 830 nm using an infrared monitor, and the visibility at a wavelength of 940 nm using an infrared monitor, for the anti-counterfeit printed matter of Comparative Example 2. [Figure 6] FIG. 13 is a graph showing the spectral reflectance in the wavelength range of 400 nm to 1000 nm for the area printed with the blue ink, the area printed with the red ink, and the area printed with the yellow ink used in printing the anti-counterfeit printed matter of Comparative Example 2. [Figure 7] FIG. 13 is a diagram showing the a* and b* values ​​in the L*a*b* color system of the red ink, orange ink, yellow ink, green ink, blue ink, and purple ink of Example 3, which is one embodiment of the present invention, and the red ink, orange ink, yellow ink, green ink, blue ink, and purple ink of Comparative Example 5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The present invention will be described in detail below. A first embodiment of the present invention relates to an anti-counterfeit printed matter CP, and a second embodiment of the present invention relates to an ink composition.

[0016] It should be understood that the present invention is not limited to the following embodiments, and includes various other embodiments within the scope of the technical ideas described in the claims.

[0017] [Anti-counterfeiting printed matter CP] The anti-counterfeiting printed matter CP according to the first embodiment of the present invention is an anti-counterfeiting printed matter CP having a printed part P0 formed on a substrate S, The printing unit P0 is The maximum reflectance in the visible wavelength range is 40% or more, The average spectral reflectance in the wavelength range of 900 nm to 950 nm is 85% or more, The average spectral reflectance in the wavelength range of 830 nm to 850 nm is 30% or more lower than the average spectral reflectance in the wavelength range of 900 nm to 950 nm, A printing area P1 formed using an ink composition containing two or more colorants; It is an anti-counterfeiting printed CP.

[0018] <Print section P0> The printing portion P0 can be formed on at least a portion of the substrate S. In some cases, the printing portion P0 can be provided on the entire surface of the substrate S.

[0019] The printing unit P0 includes a printing area P1. The printing unit P0 may be configured only with the printing area P1, or may include a printing area P2 other than the printing area P1.

[0020] <Print area P1> (Maximum reflectance in the visible wavelength range) The maximum reflectance of the printed area P1 in the visible wavelength region is 40% or more. It is preferably 45% or more, more preferably 50% or more, and even more preferably 55% or more. If the maximum reflectance in the visible wavelength region is less than 40%, the hue of the printed area P1 in the visible wavelength region becomes dark, and the design color is restricted, and the degree of freedom of color may be narrowed. If the maximum reflectance in the visible wavelength region is 40% or more, the hue of the printed area P1 in the visible wavelength region becomes bright, and the degree of freedom of color can be increased without being restricted by the design color. The printed area P1 can be made to have the same color tone as the ink composition used in normal printing. Therefore, it is difficult to detect that the counterfeit prevention measures have been taken, and even if a part of the printed area P0 is the printed area P1 to which the counterfeit prevention measures have been taken, it is possible to make the printed area P0 an integrated printed area P0 that does not feel strange.

[0021] In the present invention, the "visible wavelength region" has a lower limit of 360 nm to 400 nm, preferably 380 nm, more preferably 400 nm, and an upper limit of 760 nm to 830 nm, preferably 800 nm, more preferably 760 nm.

[0022] The maximum reflectance in the visible wavelength region can be obtained by measurement using a spectrophotometer.

[0023] (Average spectral reflectance in the wavelength range 900nm to 950nm) The printed area P1 has an average spectral reflectance of 85% or more in the wavelength range of 900 nm to 950 nm, preferably 90% or more, and more preferably 93% or more. If the average spectral reflectance in the wavelength range of 900 nm to 950 nm is 85% or more, when the printed area P1 is visually observed in the wavelength range of 900 nm to 950 nm using an infrared visualizing device, it will be visually observed as a reflective area with a white color tone.

[0024] The average spectral reflectance in the wavelength region of 900 nm to 950 nm can be obtained by measuring the spectral reflectance at predetermined wavelength intervals, preferably 1 nm intervals, starting from 900 nm using a spectrophotometer and calculating the average value of the spectral reflectances.

[0025] In the present invention, the "average spectral reflectance in the wavelength range of 900 nm to 950 nm" may be substantially the same value as the "spectral reflectance at a wavelength of 940 nm", and in such cases, this value may be used.

[0026] (Average spectral reflectance in the wavelength range 830nm to 850nm) The average spectral reflectance of the printed region P1 in the wavelength range of 830 nm to 850 nm is at least 30% lower than the average spectral reflectance in the wavelength range of 900 nm to 950 nm, preferably at least 33%, and more preferably at least 35% lower. With a difference in average spectral reflectance of 30% or more, the printed region P1 is visually recognized as having different color tones in the wavelength ranges of 830 nm to 850 nm and 900 nm to 950 nm.

[0027] The average spectral reflectance in the wavelength range of 830 nm to 850 nm can be obtained by measuring the spectral reflectance at predetermined wavelength intervals, preferably 1 nm intervals, starting from 830 nm using a spectrophotometer and calculating the average value of the spectral reflectances.

[0028] In the present invention, the "average spectral reflectance in the wavelength range of 830 nm to 850 nm" may be approximately the same value as the "spectral reflectance at a wavelength of 830 nm" or the "spectral reflectance at a wavelength of 850 nm", and in such cases, this value may be used.

[0029] (Adjustment of reflectance of print area P1) There are no particular limitations on the method for adjusting the maximum reflectance in the visible wavelength region, the average spectral reflectance in the wavelength region of 900 nm to 950 nm, and the average spectral reflectance in the wavelength region of 830 nm to 850 nm of the printed region P1 to each fall within a predetermined range.

[0030] One way to achieve a maximum reflectance of 40% or more in the visible wavelength range is to use an ink composition that forms the printing area P1 in which the amount of components that result in dark colors such as black in the visible wavelength range is reduced.

[0031] As a means for making the average spectral reflectance in the wavelength region of 900nm to 950nm 85% or more and the average spectral reflectance in the wavelength region of 830nm to 850nm 30% or more lower than the average spectral reflectance in the wavelength region of 900nm to 950nm, for example, a method of using an ink composition containing a component whose spectral reflectance changes significantly in the wavelength region of 850nm to 900nm as the ink composition for forming the printed region P1 can be mentioned. The printed region P1 formed using an ink composition containing such a component shows relatively different spectral reflectances in the wavelength regions of 900nm to 950nm and 830nm to 850nm, and in some cases, can be changed from an absorption region to a reflection region, so that the color tone visually recognized in each wavelength region can be different (white and black).

[0032] Examples of components that are not dark in the visible wavelength range and whose spectral reflectance changes significantly in the wavelength range of 850 nm to 900 nm include some blue pigments and green pigments, and in particular, titanyl phthalocyanine pigments.

[0033] (Spectral reflectance of printing area P1) The spectral reflectance of the print area P1 is, for example, as shown in FIG.

[0034] The solid line in Fig. 2 shows the spectral reflectance of the blue printed area P1 formed with blue ink from wavelengths of 400 nm to 1000 nm. As shown in Fig. 2, the blue printed area P1 exhibited reflectance characteristics specific to blue in the visible wavelength range (approximately 73% reflectance at a wavelength of 470 nm), approximately 55% at a wavelength of 830 nm, and approximately 95% at a wavelength of 940 nm.

[0035] The dotted line in Fig. 2 indicates the spectral reflectance of the yellow printed area P1 formed with yellow ink from 400 nm to 1000 nm. As shown in Fig. 2, the yellow printed area P1 exhibited reflectance characteristics specific to yellow in the visible wavelength range (approximately 74% reflectance at a wavelength of 510 nm), approximately 55% at a wavelength of 830 nm, and approximately 95% at a wavelength of 940 nm.

[0036] The dashed line in Fig. 2 indicates the spectral reflectance of the red printed area P1 formed with red ink from 400 nm to 1000 nm. As shown in Fig. 2, the red printed area P1 exhibited reflectance characteristics specific to red in the visible wavelength range (approximately 61% reflectance at a wavelength of 620 nm), approximately 55% at a wavelength of 830 nm, and approximately 95% at a wavelength of 940 nm.

[0037] (Examples of anti-counterfeit printed matter CP) FIG. 1 is a specific example of an anti-counterfeit printed matter CP according to a first embodiment of the present invention. As shown in FIG. 1, the anti-counterfeit printed matter CP has a printed portion P0 printed on a part of a substrate S, and the printed portion P0 is composed of a printed area P1 and a printed area P2. In the anti-counterfeit printed matter CP according to the first embodiment of the present invention, the printed area P1 (the pattern of "1000" in FIG. 1) is a reflective area in the wavelength range of 900 nm to 950 nm, and is therefore visually recognized as a white color tone, and in the wavelength range of 830 nm to 850 nm, it is a relatively absorbing area, and is therefore visually recognized as a black color tone. This makes it possible to easily distinguish between genuine and counterfeit.

[0038] Fig. 3 is a specific example of a printed matter according to a comparative example, printed using an ink composition generally used for printing. The printed matter shown in Fig. 3 has a printed area (the "1000" pattern in Fig. 3) that is a reflective area in both the wavelength range of 900 nm to 950 nm and the wavelength range of 830 nm to 850 nm, and is therefore visually recognized as a white color tone in both cases, and there is no difference in visibility due to the difference in wavelength range, so that it can be clearly distinguished from the anti-counterfeit printed matter CP according to the first embodiment of the present invention.

[0039] Fig. 5 is a specific example of a printed matter according to another comparative example, printed with an ink composition containing carbon black that exhibits absorption characteristics in the infrared wavelength region. The printed matter shown in Fig. 5 has a printed region (the "1000" pattern in Fig. 5) that is an absorption region in both the wavelength region of 900 nm to 950 nm and the wavelength region of 830 nm to 850 nm, and therefore is visually recognized as a black color tone in both cases, and there is no difference in visibility due to the difference in wavelength region, so that it can be clearly distinguished from the anti-counterfeit printed matter CP according to the first embodiment of the present invention.

[0040] <Ink composition> In the anti-counterfeit printed matter CP of the first embodiment of the present invention, the ink composition forming the printed area P1 is not particularly limited as long as it is an ink composition capable of forming a printed area P1 having a maximum reflectance of 40% or more in the visible wavelength range, an average spectral reflectance of 85% or more in the wavelength range of 900 nm to 950 nm, and an average spectral reflectance in the wavelength range of 830 nm to 850 nm that is 30% or more lower than the average spectral reflectance in the wavelength range of 900 nm to 950 nm, and which contains at least one type of colorant.

[0041] The ink composition contains at least one colorant, a varnish, and, if necessary, an auxiliary.

[0042] In the present invention, the ink composition is preferably an ink composition containing at least one colorant containing a titanyl phthalocyanine pigment.

[0043] In the present invention, when the ink composition contains a titanyl phthalocyanine pigment, the content of the titanyl phthalocyanine pigment is preferably 0.3% by mass or more and 25% by mass or less based on the total amount of the ink composition.

[0044] (Coloring agent) The colorant is not particularly limited as long as it is a component that can color the ink composition to a desired color tone. For example, inorganic color pigments, organic color pigments, luster pigments, dyes, fluorescent pigments, extender pigments, etc., in colors such as red, blue, yellow, green, purple, black, white, and orange, etc., may be mentioned. The colorant may have a particle surface treated with a surface treatment agent such as a rosin compound, a silane coupling agent, a resin, or a pigment derivative, if necessary. In the present invention, the ink composition contains two or more types of colorants.

[0045] Examples of inorganic color pigments include carbon black, iron black, titanium oxide, zinc oxide, zinc yellow, red iron oxide, yellow iron oxide, ultramarine blue, Prussian blue, chromium oxide green, cobalt green, composite oxides (nickel-titanium, chromium-titanium, bismuth-vanadium, cobalt-aluminum, cobalt-aluminum-chromium, ultramarine blue), etc. These may be used alone or in combination of two or more.

[0046] Examples of organic coloring pigments include phthalocyanine pigments, azo pigments, quinacridone pigments, anthraquinone pigments, dioxane pigments, indigo pigments, thioindigo pigments, perinone pigments, perylene pigments, indoline pigments, azomethine pigments, isoindolinone pigments, isoindoline pigments, dioxazine pigments, quinophthalone pigments, metal complex pigments, diketopyrrolopyrrole pigments, polycyclic pigments, threne pigments, benzimidazolone pigments, anthrapyrimidine pigments, nitro pigments, nitroso pigments, and aniline black.

[0047] Examples of the luster pigment include metal powders and metal foils such as aluminum, copper, zinc, tin, brass, and silver, oxide-coated mica such as titanium dioxide-coated mica, oxide-coated glass flakes, fish scale foil, bismuth oxychloride, and pigments having pearlescent or interference luster such as cholesteric liquid crystal pigments. These may be used alone or in combination of two or more.

[0048] Examples of dyes include water-soluble dyes, oil-soluble dyes, and disperse dyes in colors such as red, blue, yellow, green, purple, black, white, and orange. The dyes may be acid dyes, basic dyes, reactive dyes, direct dyes, and food dyes. These may be used alone or in combination of two or more.

[0049] Examples of fluorescent pigments include pigments that use light in a specific wavelength region as excitation energy and emit light in a wavelength region different from the aforementioned wavelength.

[0050] Examples of the extender pigment include talc, mica, barium sulfate, clay, calcium carbonate, kaolinite (kaolin), silicon oxide, bentonite, ground calcium carbonate, barium carbonate, zirconia, alumina, etc. These may be used alone or in combination of two or more. The volume average particle size of the extender pigment may be about 0.001 to 100 μm.

[0051] In the present invention, the ink composition is preferably an ink composition containing two or more colorants including a titanyl phthalocyanine pigment. By using such an ink composition, it is possible to easily form an anti-counterfeit printed matter CP having high counterfeit resistance.

[0052] The titanyl phthalocyanine pigment is preferably, for example, a compound represented by the following formula (1).

[0053] [ka] (In formula (1), X 1 , X 2 , X 3 and X 4 are halogen atoms, alkyl groups, alkoxy groups, cyano groups or nitro groups, and may be the same or different. a, b, c and d are integers of 0 to 4 and may be the same or different. When a, b, c and d are integers of 2 to 4, a plurality of X1 , X 2 , X 3 and X 4 may be the same or different.)

[0054] The titanyl phthalocyanine pigment is a pale blue pigment by itself. In the present invention, the titanyl phthalocyanine pigment is preferably a titanyl phthalocyanine in which a, b, c and d in the formula (1) are all 0. The crystal form of the titanyl phthalocyanine is not particularly limited. Any of the crystal forms such as Y type, A type (β type), B type (α type) and the like can be used, and Y type titanyl phthalocyanine or B type titanyl phthalocyanine is preferred. The titanyl phthalocyanine can be either a synthetic product or a commercially available product.

[0055] The printed area P1t formed from the ink composition containing the titanyl phthalocyanine pigment has different spectral reflectances in the infrared region: (i) the spectral reflectance in the visible wavelength region exhibits transmission, making it possible to brighten the hue and reduce hue limitations at the time of design; (ii) the spectral reflectance in the wavelength region of 830 nm to 850 nm exhibits absorption, so the printed area P1t can be viewed as black; and (iii) the spectral reflectance in the wavelength region of 900 nm to 950 nm exhibits transmission, so the printed area P1t can be viewed as white.

[0056] Conventionally, carbon black has been widely used as a colorant whose spectral reflectance exhibits absorption in the infrared region. However, the printed region P1c formed from an ink composition containing carbon black exhibits spectral reflectance absorption even in the visible wavelength region, so that the printed region appears dark in hue when viewed in the visible wavelength region, and since the spectral reflectance exhibits absorption in the wavelength region of 830 nm to 950 nm (the entire infrared region), the printed region P1c is perceived as black.

[0057] As a result, the authenticity of the anti-counterfeit printed matter CP of the present invention can be discriminated using two wavelength ranges within the infrared region, allowing for a high level of authenticity discrimination and providing high resistance to counterfeiting.

[0058] The amount of the two or more colorants blended in the ink composition is not particularly limited as long as the desired color tone can be obtained and the ink composition can be used for printing. For example, the total amount of the two or more colorants is 1% by mass or more and 70% by mass or less, preferably 50% by mass or less, based on the total amount of the ink composition.

[0059] In the present invention, when the ink composition contains a titanyl phthalocyanine pigment, the content of the titanyl phthalocyanine pigment is preferably 0.3% by mass or more and 25% by mass or less based on the total amount of the ink composition.

[0060] (varnish) The varnish constituting the ink composition is composed of a binder and a liquid component that dissolves or disperses the binder, and forms an ink coating film after printing to constitute the printing area P1.

[0061] (binder) Examples of the binder include resins used as binders or binding agents in the field of ink compositions and curable compounds having ethylenic unsaturated bonds. These may be used alone or in combination of two or more.

[0062] Examples of the resin include acrylic resins, polyester resins, styrene resins, polyolefin resins, epoxy resins, polyurethane resins, phenol resins, rosin resins, alkyd resins, petroleum resins, hydrocarbon resins, etc. The weight average molecular weight of these resins can be, for example, 500 or more and 1,000,000 or less.

[0063] Examples of the curable compound having an ethylenically unsaturated bond include monofunctional monomers having one ethylenically unsaturated bond in the molecule, and difunctional or higher monomers having two or more ethylenically unsaturated bonds in the molecule, which can be polymerized by light, heat, etc. to cure the ink composition. These may be used alone or in combination of two or more.

[0064] The content of the binder is not particularly limited, and can be, for example, from 5% by mass to 60% by mass with respect to the total amount of the ink composition.

[0065] (liquid component) The liquid components forming the varnish are liquid components that have been used in the preparation of ink compositions up to now, and are used to dissolve resins to make varnishes or to adjust the viscosity of the ink composition. The liquid components are those that are in a liquid state at the temperature during printing (usually 10°C to 40°C), and include organic solvents (e.g., ketone-based solvents, halogen-based solvents, hydrocarbon-based solvents, petroleum-based solvents, ether-based solvents, ester-based solvents, glycol ether-based solvents, amide-based solvents, etc.), animal and vegetable oils, animal and vegetable oil derivatives, mineral oils, water, etc. These may be used alone or in combination of two or more.

[0066] (auxiliary agent) The ink composition for forming the anti-counterfeit printed matter CP of the present invention may contain an auxiliary agent as necessary. The auxiliary agent is not particularly limited as long as it is used as an auxiliary agent for printing ink. For example, dispersants, surfactants, drying agents, waxes, gelling agents, viscosity modifiers, antioxidants, bactericides and antifungal agents may be mentioned. These may be used alone or in combination of two or more.

[0067] The dispersant may be any of anionic dispersants, cationic dispersants, amphoteric dispersants and nonionic dispersants, and examples thereof include polymer dispersants, low molecular weight compounds (surfactants), pigment derivatives, etc. These may be used alone or in combination of two or more.

[0068] Examples of the surfactant include anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, fluorine-based surfactants, silicone-based surfactants, etc. These may be used alone or in combination of two or more.

[0069] Examples of the drying agent include metal dryers formed from various metals and higher fatty acids, etc. These may be used alone or in combination of two or more.

[0070] Examples of waxes include vegetable waxes, animal waxes, petroleum waxes, synthetic waxes, etc. These may be used alone or in combination of two or more.

[0071] Examples of the gelling agent include metal chelate compounds, organic acid metal salts (metal soaps), and metal soap oligomers.

[0072] Examples of the viscosity modifier include the animal and vegetable oils and / or the animal and vegetable oil derivatives, polyvinyl alcohol, cellulose compounds, polyamines, polyimines, starch compounds, alginic acid compounds, fatty acid ester compounds, polyacrylic acid compounds, etc. These may be used alone or in combination of two or more.

[0073] Examples of the antioxidant include phenol-based antioxidants, amine-based antioxidants, sulfur-based antioxidants, phosphorus-based antioxidants, etc. These may be used alone or in combination of two or more.

[0074] Examples of the bactericide and antifungal agent include sodium dehydroacetate, sodium benzoate, sodium pyridinethione-1-oxide, p-hydroxybenzoic acid ethyl ester, 1,2-benzisothiazolin-3-one and salts thereof, etc. These may be used alone or in combination of two or more.

[0075] <Printing method / base material S> The printing method used when producing the anti-counterfeit printed matter CP according to the first embodiment of the present invention is not particularly limited. For example, printing methods such as offset printing (offset printing using dampening water, offset printing without dampening water), intaglio printing, letterpress printing, lithographic printing, stencil printing, letterpress printing, screen printing, gravure printing, flexographic printing, electrophotographic printing, and inkjet printing can be used. When printing the anti-counterfeit printed matter CP, one of these printing methods may be used alone, or two or more printing methods may be used.

[0076] The substrate S used in producing the anti-counterfeit printed matter CP according to the first embodiment of the present invention is not particularly limited. Substrate S of any shape, such as a sheet or a three-dimensional shape, can be used. Examples of materials constituting the substrate S include paper, plastic, metal, glass, ceramic, wood, and composites of two or more of these materials.

[0077] <Authenticity determination method> The anti-counterfeit printed matter CP according to the first embodiment of the present invention can be used to discriminate between genuine and counterfeit by utilizing the characteristic spectral reflectance characteristics of the print area P1 in the visible wavelength region and the infrared wavelength region.

[0078] Since printed area P1 exhibits transmittance in the visible wavelength range, it is possible to brighten the hue and reduce hue restrictions during design. Therefore, even when combined with a printed area (printed area P2) using inks of various commonly used color tones, it is possible to create an anti-counterfeiting printed matter CP with a natural, integrated design.

[0079] Furthermore, in the wavelength region of 830 nm to 850 nm, the spectral reflectance shows absorption, so that the printed region P1 can be visually recognized as black, whereas in the wavelength region of 900 nm to 950 nm, the spectral reflectance shows transmission, so that the printed region P1 can be visually recognized as white to gray, and thus shows different spectral reflectances in the infrared region. As a result, the anti-counterfeit printed matter CP of the present invention can be discriminated for authenticity using two wavelength regions in the infrared region, so that a high level of authenticity discrimination is possible and it has high counterfeit resistance.

[0080] When discriminating the authenticity of the anti-counterfeit printed matter CP of the present invention, for example, a method of discriminating authenticity having the following steps can be used.

[0081] (Step 1) Measure the average spectral reflectance in the wavelength region of 830 to 850 nm. Note that the average spectral reflectance in the wavelength region of 830 to 850 nm may be approximately the same as the spectral reflectance at a wavelength of 830 nm or 840 nm, and in such cases, this may be used.

[0082] (Step 2) Measure the average spectral reflectance in the wavelength region of 900 to 950 nm. Note that the average spectral reflectance in the wavelength region of 900 to 950 nm may be approximately the same as the spectral reflectance at a wavelength of 940 nm, and in such cases, this may be used.

[0083] (Step 3) The difference between the average spectral reflectance measured in the 830-850 nm wavelength range and the average spectral reflectance measured in the 900-950 nm wavelength range is calculated, and compared with the allowable range value (a difference in average spectral reflectance of 30% or more) to determine authenticity.

[0084] To more easily distinguish between genuine and counterfeit, the printed portion P0 is viewed using an infrared visualization device in the wavelength region of 830 nm to 850 nm and in the wavelength region of 900 nm to 950 nm to confirm the difference in color tone, thereby making it possible to distinguish between genuine and counterfeit. When the printed portion P0 is viewed using an infrared visualization device in the wavelength region of 830 nm to 850 nm, a part of the printed portion P0 is viewed as black, while when viewed in the wavelength region of 900 nm to 950 nm, the part of the printed portion P0 that was viewed as black in the wavelength region of 830 nm to 850 nm is recognized as white, making it easy to distinguish between genuine and counterfeit.

[0085] As the infrared visualization device used in determining the authenticity of the printed part P0, for example, an infrared camera, a CCD, a CMOS sensor, or the like can be used.

[0086] Infrared monitors and general image sensors can also be used. To read only specific wavelength ranges, a filter that cuts visible light and a light source that emits only light of a specific wavelength (such as an infrared LED) or a bandpass filter that transmits only light of a specific wavelength and a light source that emits near-infrared light (such as an incandescent light bulb) can be combined with an image sensor.

[0087] <Application> The anti-counterfeiting printed matter CP according to the first embodiment of the present invention can be used as various printed matters that require anti-counterfeiting, particularly as security printed matters that require advanced anti-counterfeiting technology and printed matters that require design, such as banknotes (paper money), revenue stamps, postage stamps, gift certificates, coupons, admission tickets, securities, various certificates, passports, security labels, etc.

[0088] [Ink composition] The ink composition according to the second embodiment of the present invention is an ink composition containing two or more colorants, The printing area P3 formed using the ink composition is The maximum reflectance in the visible wavelength range is 40% or more, The average spectral reflectance in the wavelength range of 900 nm to 950 nm is 85% or more, The average spectral reflectance in the wavelength range of 830 nm to 850 nm is 30% or more lower than the average spectral reflectance in the wavelength range of 900 nm to 950 nm. The ink composition. The ink composition according to the second embodiment of the present invention is useful as an ink composition for anti-counterfeit printed matter CP due to the characteristic reflectance of the printed area P3 that is formed.

[0089] The specific configuration of the ink composition according to the second embodiment of the present invention can be the same as that of the ink composition used to form the printing area P1 having a specific reflectance in the anti-counterfeit printed matter CP according to the first embodiment.

[0090] The printed area P3 formed using the ink composition according to the second embodiment of the present invention is substantially identical to the printed area P1 contained in the anti-counterfeit printed matter CP according to the first embodiment of the present invention. EXAMPLES

[0091] The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited thereto. In each example, "parts" means parts by mass and "%" means % by mass.

[0092] In Examples 1 to 3 and Comparative Examples 1 to 5, CI Pigment Blue 15:3 was used as the blue colorant, CI Pigment Red 185 was used as the red colorant, and CI Pigment Yellow 180 was used as the yellow colorant, respectively.

[0093] In Example 3 and Comparative Example 5, CI Pigment Orange 16 was used as the orange colorant, CI Pigment Green 36 was used as the green colorant, and CI Pigment Violet 23 was used as the purple colorant, respectively.

[0094] In Examples 1 to 3 and Comparative Examples 1 to 5, the "average spectral reflectance in the wavelength range of 830 nm to 850 nm" is approximately the same value as the "spectral reflectance at a wavelength of 830 nm" or the "spectral reflectance at a wavelength of 840 nm," so the value of the "spectral reflectance at a wavelength of 830 nm" or the "spectral reflectance at a wavelength of 840 nm" was used.

[0095] In Examples 1 to 3 and Comparative Examples 1 to 5, the "average spectral reflectance in the wavelength range of 900 nm to 950 nm" is approximately the same value as the "spectral reflectance at a wavelength of 940 nm," so the value of the "spectral reflectance at a wavelength of 940 nm" was used.

[0096] [Example 1, Comparative Examples 1 and 2] <Example 1> (Ink Creation) A blue ink was prepared by mixing 8.0% by mass of blue colorant and 1.0% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0097] Red ink was prepared by mixing 8.0% by mass of red colorant and 1.0% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0098] A yellow ink was prepared by mixing 8.0% by mass of a yellow colorant and 1.0% by mass of titanyl phthalocyanine with respect to the total amount of the ink.

[0099] (Visual confirmation of color tone of printed matter) The prepared blue, red, and yellow inks were mixed and printed using an offset printing machine to obtain a printed matter with the number "1000" printed in the specified color tone.

[0100] The obtained prints were visually observed in the visible wavelength range, and visually observed using an infrared monitor at a wavelength of 830 nm and at a wavelength of 940 nm. The results are shown in FIG.

[0101] As shown in Figure 1, when the printed matter of Example 1 was viewed in the visible wavelength range (Figure 1(a)), the "1000" pattern was viewed in a specified color tone, when viewed using an infrared monitor at a wavelength of 830 nm (Figure 1(b)), the "1000" pattern was viewed in a black tone, and when viewed using an infrared monitor at a wavelength of 940 nm (Figure 1(c)), the "1000" pattern was viewed in a white tone.

[0102] (Spectral reflectance of each color) Using the prepared blue, red and yellow inks, solid patterns with an ink thickness of 1 μm were printed using an IGT color developer to prepare blue, red and yellow printed areas P1, respectively. The spectral reflectance of each of the prepared blue, red and yellow printed areas P1 was measured. The results are shown in Figure 2.

[0103] 2, the blue, red, and yellow printed areas P1 according to Example 1 all exhibited a reflectance of approximately 55% at a wavelength of 830 nm and approximately 95% at a wavelength of 940 nm. In addition, in the visible wavelength region, the blue printed area P1 exhibited a reflectance of approximately 73% at a wavelength of 470 nm, the red printed area P1 exhibited a reflectance of approximately 61% at a wavelength of 620 nm, and the yellow printed area P1 exhibited a reflectance of approximately 74% at a wavelength of 510 nm, all of which exhibited high reflectance, indicating that all of the printed areas P1 exhibited bright hues.

[0104] From this, it can be seen that the blue, red, and yellow printed area P1 according to Example 1 has a bright hue in the visible wavelength range, and therefore there are no restrictions on design colors, allowing for a high degree of color freedom.

[0105] <Comparative Example 1> (Ink Creation) A blue ink was prepared by adding 8.0% by mass of blue colorant to the total amount of ink, without adding titanyl phthalocyanine to the ink.

[0106] A red ink was prepared by adding 8.0% by mass of red colorant to the total amount of ink, without adding titanyl phthalocyanine to the ink.

[0107] A yellow ink was prepared by adding 8.0% by mass of a yellow colorant to the total amount of the ink, without adding titanyl phthalocyanine to the ink.

[0108] (Visual confirmation of color tone of printed matter) Using the prepared blue, red and yellow inks, a printed matter having a "1000" design in a predetermined color tone was obtained in the same manner as in Example 1.

[0109] The obtained print was visually observed in the visible wavelength region at wavelengths of 830 nm and 940 nm in the same manner as in Example 1. The results are shown in FIG.

[0110] As shown in Figure 3, when the printed matter of Comparative Example 1 was viewed in the visible wavelength range (Figure 3(a)), the "1000" pattern was viewed in a specified color tone, when viewed using an infrared monitor at a wavelength of 830 nm (Figure 3(b)), the "1000" pattern was viewed in a white tone, and when viewed using an infrared monitor at a wavelength of 940 nm (Figure 3(c)), the "1000" pattern was viewed in a white tone.

[0111] (Spectral reflectance of each color) Using the prepared blue, red, and yellow inks, blue, red, and yellow printed areas were prepared in the same manner as in Example 1. The spectral reflectance of each of the prepared blue, red, and yellow printed areas was measured. The results are shown in FIG.

[0112] As shown in FIG. 4, the blue, red and yellow printed areas according to Comparative Example 1 all exhibited a reflectance of approximately 90% at a wavelength of 830 nm and approximately 90% at a wavelength of 940 nm.

[0113] In addition, in the visible wavelength region, the blue printed region exhibited reflectance characteristics similar to those of Example 1, with a reflectance of approximately 72% at a wavelength of 470 nm, the red printed region exhibiting reflectance of approximately 90% at a wavelength of 620 nm, and the yellow printed region exhibiting reflectance of approximately 80% at a wavelength of 510 nm.

[0114] <Comparative Example 2> (Ink Creation) A blue ink was prepared by mixing 8.0% by mass of blue colorant and 1.0% by mass of carbon black based on the total amount of ink.

[0115] Red ink was prepared by mixing 8.0% by mass of red colorant and 1.0% by mass of carbon black based on the total amount of ink.

[0116] A yellow ink was prepared by mixing 8.0% by mass of a yellow colorant and 1.0% by mass of carbon black based on the total amount of the ink.

[0117] (Visual confirmation of color tone of printed matter) Using the prepared blue, red and yellow inks, a printed matter having a "1000" design in a predetermined color tone was obtained in the same manner as in Example 1.

[0118] The obtained print was visually observed in the visible wavelength region at wavelengths of 830 nm and 940 nm in the same manner as in Example 1. The results are shown in FIG.

[0119] As shown in Figure 5, when the printed matter of Comparative Example 2 was viewed in the visible wavelength range (Figure 5(a)), the "1000" pattern was viewed in a specified color tone, when viewed using an infrared monitor at a wavelength of 830 nm (Figure 5(b)), the "1000" pattern was viewed in a black tone, and when viewed using an infrared monitor at a wavelength of 940 nm (Figure 5(c)), the "1000" pattern was viewed in a black tone.

[0120] (Spectral reflectance of each color) Using the prepared blue, red, and yellow inks, blue, red, and yellow printed areas were prepared in the same manner as in Example 1. The spectral reflectance of each of the prepared blue, red, and yellow printed areas was measured. The results are shown in FIG.

[0121] As shown in FIG. 6, the blue, red and yellow printed areas according to Comparative Example 2 all exhibited a reflectance of approximately 58% at a wavelength of 830 nm and approximately 60% at a wavelength of 940 nm.

[0122] On the other hand, in the visible wavelength range, the blue printed area shows approximately 43% at a wavelength of 470 nm, the red printed area shows approximately 52% at a wavelength of 620 nm, and the yellow printed area shows approximately 43% at a wavelength of 510 nm, indicating that all colors have low reflectance and dark hues.

[0123] This means that the hue is dark in the visible wavelength range, which restricts the design colors and limits the color freedom.

[0124] [Example 2, Comparative Examples 3 and 4] <Example 2> (Ink Creation) A blue ink was prepared by mixing 15.0% by mass of blue colorant and 1.0% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0125] A red ink was prepared by mixing 15.0% by mass of red colorant and 1.0% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0126] A yellow ink was prepared by mixing 15.0% by mass of a yellow colorant and 1.0% by mass of titanyl phthalocyanine with respect to the total amount of the ink.

[0127] (For each color, L * Value, a * Value, b * Value and color difference ΔE * value) Using the prepared blue, red and yellow inks, solid patterns with an ink thickness of 1 μm were printed using an IGT color developer to prepare blue, red and yellow print areas P1, respectively. * Value, a * value and b * The values ​​were measured and the results are shown in Table 1.

[0128] In addition, the color value in the Lab color system of Example 2 is (L * EX2 , a * EX2 , b* EX2 ), and the color value in the Lab color system of Comparative Example 3 (L * RF3 , a * RF3 , b * RF3 ) is the color difference ΔE between the printed area P1 of each color in Example 2 and the printed area of ​​each color in Comparative Example 3. * The following formula: ΔE * =[(L * RF3 -L * EX2 ) 2 +(L * RF3 -L * EX2 ) 2 +(L * RF3 -L * EX2 ) 2 ] 1 / 2 The results are shown in Table 1.

[0129] (Spectral reflectance and difference between 830nm and 940nm wavelengths for each color) Using the prepared blue, red, and yellow inks, solid patterns with an ink thickness of 1 μm were printed using an IGT color developer to prepare blue, red, and yellow printed areas P1, respectively. The spectral reflectance at a wavelength of 830 nm and the spectral reflectance at a wavelength of 940 nm were measured for each of the prepared blue, red, and yellow printed areas P1, and the absolute value of the difference in the spectral reflectance was calculated. The results are also shown in Table 1.

[0130] <Comparative Example 3> (Ink Creation) A blue ink was prepared by adding 15.0% by mass of blue colorant to the total amount of ink, without adding titanyl phthalocyanine to the ink.

[0131] A red ink was prepared by adding 15.0% by mass of red colorant to the total amount of ink, without adding titanyl phthalocyanine to the ink.

[0132] A yellow ink was prepared by adding 15.0% by mass of a yellow colorant to the total amount of the ink, without adding titanyl phthalocyanine to the ink.

[0133] (For each color, L * Value, a * value and b * value) Using the prepared blue, red and yellow inks, blue, red and yellow printed areas were prepared in the same manner as in Example 2. For each of the prepared blue, red and yellow printed areas, the L * Value, a * value and b * The values ​​were measured and the results are shown in Table 1.

[0134] (Spectral reflectance and difference between 830nm and 940nm wavelengths for each color) Using the prepared blue, red, and yellow inks, blue, red, and yellow printed areas were prepared in the same manner as in Example 2. For each of the prepared blue, red, and yellow printed areas, the spectral reflectance at a wavelength of 830 nm and the spectral reflectance at a wavelength of 940 nm were measured, and the absolute value of the difference in the spectral reflectance was calculated. The results are also shown in Table 1.

[0135] <Comparative Example 4> (Ink Creation) A blue ink was prepared by mixing 15.0% by mass of blue colorant and 1.0% by mass of carbon black based on the total amount of ink.

[0136] Red ink was prepared by mixing 15.0% by mass of red colorant and 1.0% by mass of carbon black based on the total amount of ink.

[0137] A yellow ink was prepared by mixing 15.0% by mass of a yellow colorant and 1.0% by mass of carbon black based on the total amount of the ink.

[0138] (For each color, L * Value, a * Value, b * Value and color difference ΔE * value) Using the prepared blue, red and yellow inks, blue, red and yellow printed areas were prepared in the same manner as in Example 2. For each of the prepared blue, red and yellow printed areas, the L * Value, a * value and b * The values ​​were measured and the results are shown in Table 1.

[0139] In addition, the color value in the Lab color system of Comparative Example 4 is (L * RF4 , a * RF4 , b * RF4 ), and the color value in the Lab color system of Comparative Example 3 (L * RF3 , a * RF3 , b * RF3 ) and the color difference ΔE * The following formula: ΔE * =[(L * RF3 -L * RF4 ) 2 +(L * RF3 -L * RF4 ) 2 +(L * RF3 -L * RF4 ) 2 ] 1 / 2 The results are shown in Table 1.

[0140] (Spectral reflectance and difference between 830nm and 940nm wavelengths for each color) Using the prepared blue, red and yellow inks, blue, red and yellow printed areas were prepared in the same manner as in Example 2. For each of the prepared blue, red and yellow printed areas, the spectral reflectance at a wavelength of 830 nm and the spectral reflectance at a wavelength of 940 nm were measured, and the absolute value of the difference in the spectral reflectance was calculated. The results are also shown in Table 1.

[0141] [Table 1]

[0142] [Example 3, Comparative Example 5] <Example 3> (Ink Creation) Red ink a was prepared by mixing 9.0% by mass of red colorant and 1.2% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0143] Orange ink b was prepared by mixing 9.0% by mass of orange colorant and 1.2% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0144] Yellow ink c was prepared by mixing 9.0% by mass of yellow colorant and 1.2% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0145] Green ink d was prepared by mixing 9.0% by mass of green colorant and 1.2% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0146] Blue ink e was prepared by mixing 9.0% by mass of blue colorant and 1.2% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0147] Purple ink f was prepared by mixing 9.0% by mass of purple colorant and 1.2% by mass of titanyl phthalocyanine with respect to the total amount of ink.

[0148] (For each color, a * Value, b * value and spectral reflectance at a wavelength of 840 nm) Using the prepared red, orange, yellow, green, blue and purple inks a to f, printing was performed so that the spectral reflectance at a wavelength of 840 nm in the printing area P1 was about 50%, and the red, orange, yellow, green, blue and purple printing areas P1 were prepared. * Value, b * The value and the spectral reflectance at a wavelength of 840 nm were measured. The results are shown in Table 2.

[0149] Also, a * Value on the horizontal axis, b * The vertical axis represents the value, and the vertical axis represents the (a * Value, b * The results are also shown in Figure 7.

[0150] <Comparative Example 5> (Ink Creation) Red ink a' was prepared by mixing 9.0% by mass of red colorant and 1.2% by mass of carbon black based on the total amount of ink.

[0151] Orange ink b' was prepared by mixing 9.0% by mass of orange colorant and 1.2% by mass of carbon black based on the total amount of ink.

[0152] Yellow ink c' was prepared by mixing 9.0% by mass of yellow colorant and 1.2% by mass of carbon black based on the total amount of ink.

[0153] Green ink d' was prepared by mixing 9.0% by mass of green colorant and 1.2% by mass of carbon black based on the total amount of ink.

[0154] Blue ink e' was prepared by mixing 9.0% by mass of blue colorant and 1.2% by mass of carbon black based on the total amount of ink.

[0155] Purple ink f' was prepared by mixing 9.0% by mass of purple colorant and 1.2% by mass of carbon black based on the total amount of ink.

[0156] (For each color, a * Value, b * value and spectral reflectance at a wavelength of 840 nm) Using the prepared red, orange, yellow, green, blue and purple inks a' to f', printing was performed so that the spectral reflectance at a wavelength of 840 nm in the printed area was about 50%, and red, orange, yellow, green, blue and purple printed areas were produced. * Value, b * The value and the spectral reflectance at a wavelength of 840 nm were measured. The results are shown in Table 2.

[0157] Also, a * Value on the horizontal axis, b * The vertical axis indicates the value of the ink, and the vertical axis indicates the number of inks (a' to f') used for printing. * Value, b * The results are also shown in Figure 7.

[0158] As shown in FIG. 7, the printed area P1 of each color made with the ink composition of each color containing the colorant of each color and titanyl phthalocyanine has a difference of a in the Lab color system compared to the printed area of ​​each color made with the ink composition of each color containing the colorant of each color and carbon black. * value and b * The values ​​are high for all colors, and it can be seen that the hue reproduction range is wide.

[0159] [Table 2]

[0160] Although the present invention has been described in detail above, various modifications can be made in the above configuration without departing from the scope of the present invention. Therefore, all matters contained in the above description or shown in the accompanying drawings should be interpreted as illustrative. [Explanation of symbols]

[0161] CP: Anti-counterfeiting printed matter S: Base material P0: Printing department P1:Print area P1 P2:Print area P2

Claims

1. An anti-counterfeiting printed matter having a printed portion formed on a substrate, The printing unit includes: The maximum reflectance in the visible wavelength region is 40% or more, The average spectral reflectance in the wavelength range of 900 nm to 950 nm is 85% or more, A printed area has an average spectral reflectance in the wavelength range of 830 nm to 850 nm that is 30% or more lower than the average spectral reflectance in the wavelength range of 900 nm to 950 nm. The anti-counterfeiting printed matter.

2. The ink composition for printing the anti-counterfeit printed matter according to claim 1, The ink composition includes at least one colorant containing a titanyl phthalocyanine pigment.

3. The ink composition according to claim 2 , wherein the content of the titanyl phthalocyanine pigment is 0.3% by mass or more and 25% by mass or less based on the total amount of the ink composition.

Images