JP2008031594A - Sheet-like article for preventing forgery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet-like article for preventing forgery, whose dropped portions can be colored to easily confirm the traces of falsification under visible light, even if various organic solvents are dropped on the article, and to provide a means for improving the penetration and diffusion of the organic solvent in the sheet-like article to have brilliant color. <P>SOLUTION: This sheet-like article contains a water-insoluble and organic solvent-soluble dye and/or pigment. Or, a coating layer containing the dye or the pigment is disposed on the sheet-like article. The trace of falsification can visually be recognized under visible light by dropping an organic solvent. It is preferable that a plurality of the dyes and/or the pigments capable of being dissolved in organic solvents having different solubility parameters are contained. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an anti-counterfeit sheet. More specifically, the present invention relates to a forgery-preventing sheet-like material that can easily be visually recognized under visible light even if tampering is attempted using an organic solvent.

  Bills, gift certificates, passports, stock certificates, checks, etc. have various anti-counterfeiting measures to prevent them from being counterfeited. For example, it has been considered to provide forgery prevention means that can be easily visually recognized without using special equipment under natural light or normal illumination. Based on this idea, various proposals have been made for anti-counterfeit paper and anti-counterfeit printed matter that allow easy viewing of tampered traces, and materials used for these as shown below.

  For example, in Patent Document 1 and Patent Document 2, there is a proposal for a security paper that contains manganese ferrosite anide in a paper and turns brown when an attempt is made to erase characters written in the amount column using an ink eraser. is there.

  Patent Document 3 proposes a falsification-preventing paper in which a substance that changes color by an oxidizing agent, a tannin, and a penetrating agent are processed into paper, and when the ink is erased, the color does not disappear.

  Patent Document 4 proposes a safety paper that exhibits a fluorescent color when a water-soluble pyrenesulfonic acid metal salt-based reactive fluorescent dye is contained in the paper and attempts to tamper with ink erasing or weak alkali.

  In Patent Document 5, a leuco dye and a phenolic substance, a coloring layer mainly composed of a binder is provided on the surface of the paper, and when tampering with an organic solvent is attempted, the leuco dye and the phenolic substance are eluted by the penetration of the organic solvent. There is a proposal for a falsification-preventing paper in which the two chemically react to develop color. Further, Patent Documents 6 to 9 propose a label or a seal provided with a falsification preventing technique that reacts with an organic solvent to develop a color by combining a leuco dye and a developer.

  Further, the present applicant previously described in Patent Document 10 that water-insoluble and organic solvent-soluble fluorescent dye particles are contained in the paper, and when falsification is attempted with the organic solvent, the dye is eluted and permeated to exhibit a fluorescent color. Made a proposal. However, when an organic solvent is dropped on the paper, the penetration of the organic solvent is poor, and therefore, traces of alteration may not be clearly determined. In addition, applications are limited due to low printability.

Japanese Patent No. 78774 Patent No. 77962 Patent No. 136286 Patent No. 1414483 JP 63-182496 A JP 07-271302 A JP-A-10-250228 Japanese Patent Laid-Open No. 10-268772 JP 2003-29637 A JP 2000-129596 A

  For the purpose of tampering with the contents printed on the surface of the printed matter, it is convenient to have a forgery prevention means that can easily visually recognize the tampering trace when trying to remove the printing ink using various organic solvents. This invention makes it a subject to provide the sheet-like material for forgery prevention useful as such a means. Specifically, even when a plurality of types of organic solvents having different solubility parameters are dropped, the dropping portion develops color, and a forgery-preventing sheet-like material that can easily check the trace of tampering under visible light Is to provide. Another object of the present invention is to provide a means for making the color development clearer by improving the penetration and diffusion of the organic solvent in the sheet-like material.

  That is, the invention according to claim 1 of the present invention includes one or more water-insoluble and organic solvent-soluble dyes and / or pigments, and visually recognizes tampering traces caused by the dropping of one or more organic solvents under visible light. A forgery-preventing sheet-like material characterized in that it is made possible.

  That is, in the invention according to claim 2 of the present invention, the coating layer containing at least one kind of water-insoluble and organic solvent-soluble dye and / or pigment is present on at least one side of the sheet-like material, and at least one kind of organic solvent is used. It is a forgery-preventing sheet-like material characterized in that traces of tampering caused by dripping can be visually recognized under visible light.

  That is, the invention according to claim 3 of the present invention is the anti-counterfeit sheet-like material according to claim 1 or 2, wherein a coating layer containing a filler and a binder is present.

  That is, the invention according to claim 4 of the present invention is characterized in that when two or more kinds of organic solvents having different solubility parameters are dropped, the trace of dropping can be visually recognized in any case under visible light. It is a sheet material for forgery prevention of any one of -3.

  That is, the invention according to claim 5 of the present invention is characterized in that the sheet-like material is made of wood pulp as a main raw material, and the anti-counterfeit sheet-like material according to any one of claims 1 to 4. It is a thing.

  That is, the invention according to claim 6 of the present invention is characterized in that the water-insoluble and organic solvent-soluble dye is an azo dye, an aminoketone dye, or a coumarin dye. The anti-counterfeit sheet material described in 1.

  That is, the invention according to claim 7 of the present invention is the counterfeit according to any one of claims 1 to 5, wherein the water-insoluble and organic solvent-soluble pigment is an azo pigment or a phthalocyanine pigment. It is a sheet for prevention.

  According to the anti-counterfeit sheet according to the present invention, a coating layer containing at least one kind of water-insoluble and organic solvent-soluble dyes and / or pigments is provided, and there is also a coating layer containing a filler and a binder. In order to tamper with the contents printed on the surface of the printed matter, when you try to remove the printing ink using various organic solvents, you can easily see the trace of tampering, so banknotes, gift certificates , Passports, stock certificates, checks and the like can be preferably used as anti-counterfeiting means.

  The dye and / or pigment used in the present invention must be water-insoluble and organic solvent-soluble. This is because, if it is water-soluble, the dye particles dissolve in water during the production of a sheet or the like, and the object of the present invention cannot be achieved. In addition, forgery prevention paper is usually printed using oil-soluble ink, and variable information such as address, name, and amount is usually written with a ballpoint pen using oil-soluble ink. In order to falsify information, it is necessary to use an organic solvent. For this reason, if the dye and / or pigment used in the present invention is not soluble in an organic solvent, the trace of tampering cannot be visually recognized when attempting to tamper with the organic solvent.

  The dyes and / or pigments used in the present invention are those in which traces of tampering are developed under ordinary photogens when attempting to tamper with an organic solvent. What can be done is preferred.

  Any dye particles can be used as long as they are water-insoluble and organic solvent-soluble. For example, various dyes such as azo series, amino ketone series, coumarin series, oxazole series, and pyralizone series are exemplified, but the dye is not limited to these. This type of dye is sold by a dye maker, but examples include “Oil Red 5B” (manufactured by Orient Chemical Industries), “Yellowfluor 10GN” (manufactured by LANXESS), “ “Kayaset Flavine FN” (manufactured by Nippon Kayaku Co., Ltd.), “Leucopher EF 2N” (manufactured by Clariant Co., Ltd.), “TBO” (manufactured by Sumitomo Seika Co., Ltd.), “Kayaset Red SF-R” (Nihon Kasei) Yakuhin Co., Ltd.), “VALIFAST BLUE 1605” (Orient Chemical Industries, Ltd.), “Oil Green BG” (Orient Chemical Industries, Ltd.), “VALIFAST RED 2303” (Orient Chemical Industries, Ltd.) ), "Oil Blue BOS" (Orient Chemical Co., Ltd.) Manufacture), "SPILON RED GEH Special" (Hodogaya Chemical Industries, Ltd.), "MACROLEX VIOLET 3R" (Manufactured by LANXESS), "MACROLEX Red 5B FG" (Manufactured by LANXESS), "MACROLEX Green 5B" "(Manufactured by LANXESS)", "Kayfect Blue T" (manufactured by Nippon Kayaku Co., Ltd.), "Kayaset Blue 814" (manufactured by Nippon Kayaku Co., Ltd.), "SPILON BLUE 2BNH" (Hodogaya Chemical Co., Ltd.) ) Manufacturing), “SPIRON GREEN 3GNH Special” (manufactured by Hodogaya Chemical Co., Ltd.), etc., but is not limited thereto. Among these, azo dyes, aminoketone dyes, and coumarin dyes are particularly preferable because the coloring under visible light is colored and bright.

  Examples of the pigment used in the present invention include azo, phthalocyanine, anthraquinone, perlin, pyranthrone, quinacridone, dioxazine, isoindolinone, thioindigo, quinophthalone, metal, pigment, carbon, Sulfur oxide, cuprous oxide, sulfate, carbonate, silicate, chromate, aluminate, ferrocyanine and other organic or inorganic pigments are included, but are not limited to these Is not to be done. Examples of product names include “TB-200 Red GY”, “TB-500 Orange R”, “TB-520 BLUE 2B”, “TB-510 Green B”, “Seika First Carmine 1476T-7”, “A120 "Red", "430 Brilliant Bordeaux 10B", "Mono Azo Lake 10G", "Seika First Red 116", "Seika First Yellow 1983-10G" (all manufactured by Dainichi Seika Kogyo Co., Ltd.), etc. Is not to be done. In particular, it is preferable to use an azo pigment or a phthalocyanine pigment because the color development under visible light is colored and vivid.

  The dye and / or pigment used in the present invention is in the form of particles. The size of the particles is usually 200 μm or less. In the present invention, it is preferable to use particles having a particle size of 50 μm or less for the purpose of being dispersed in the paint.

  The dye and / or pigment used in the present invention is preferably used by mixing two or more kinds of dyes and / or pigments as required. In particular, it is particularly preferable to select and mix different dyes and / or pigments so that they can be dissolved in two or more types of organic solvents having different solubility parameters, since they can be arbitrarily adapted to tampering with various organic solvents. .

  Organic solvents used for falsification include various organic solvents such as methanol, ethanol, aniline, isopropyl alcohol, acetone, methyl ethyl ketone, chloroform, cresol, acetonitrile, benzene, cyclohexane, ethyl acetate, toluene, octane, mixtures thereof, and petroleum middle distillates. A naphtha that is a minute can be considered. These organic solvents differ in the types of dyes and pigments that can be eluted due to differences in solubility parameters. Therefore, as described above, by mixing two or more water-insoluble and organic solvent-soluble dyes and / or pigments and adding them to the sheet-like material, it is possible to develop color for a plurality of organic solvents having different solubility. Therefore, a higher level of anti-tampering effect can be obtained than when a dye or pigment is used alone.

The solubility parameter is a value also called an sp value, and is one factor that determines the solubility of the polymer and the solvent. In general, polar polymers tend to be soluble in polar solvents and difficult to dissolve in nonpolar solvents. On the other hand, nonpolar polymers tend to reverse. A factor for judging the strength of this affinity is a solubility parameter, which is indicated by δ. It is defined as δ = (ΔH / V) ^1/2 where ΔH is the molar evaporation heat of a liquid and V is the molar volume. Table 1 shows typical solvent solubility parameter values.
(Table 1) Solubility parameter sp value of various solvents: Solubility parameter value

  Examples of the sheet-like material used as the substrate in the present invention include paper, film, nonwoven fabric, and synthetic paper. As the paper, wood pulp generally used for papermaking, for example, softwood bleached kraft pulp (NBKP), hardwood bleached kraft pulp (LBKP), softwood bleached sulfite pulp (NBSP), thermomechanical pulp (TMP), etc. As a main component, non-wood pulp such as hemp, bamboo, straw, kenaf, modified pulp such as cationized pulp, mercerized pulp, microfibrillated pulp, rayon, vinylon, nylon Recycled fibers such as acrylic and polyester, semi-synthetic fibers, and synthetic fibers can be appropriately mixed and used. Examples of the film include materials such as polyester resins, polyethylene terephthalate resins, diacetate resins, triatesate resins, acrylic resins, polycarbonate resins, polyvinyl chloride resins, polyimide resins, cellophane, and celluloid. Nonwoven fabrics include those produced by dry, wet, and direct methods using materials such as rayon, vinylon, nylon, acrylic, polyester, cotton, pulp, hemp, wool, and glass fiber. Examples of synthetic paper include polypropylene, polystyrene, polyethylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyamide, and the like, which are produced by a stretching method. However, none are limited to those described above.

  In the present invention, a commonly used general method can be used as a method for incorporating a dye and / or pigment into a sheet-like material. For example, paper or non-woven fabric can be dispersed in the raw material, and film can be kneaded into the raw material. It is also possible to perform coating on the surface of other sheet-like materials.

  In the present invention, when a dye and / or pigment is applied to a sheet, kaolin, calcium carbonate, titanium oxide, clay, talc, aluminum hydroxide, zinc oxide, aluminum silicate, calcium silicate, synthetic amorphous It is preferable to apply inorganic fillers such as silica and zeolite, filler components generally used for coating, such as styrene or acrylic plastic pigments and polyethylene. If they are not contained at all, the penetration of the organic solvent into the coating layer is slow, which hinders the phenomenon of dye elution, and may cause blistering and blocking, which is not preferable.

  The coating layer containing the dye and / or pigment in the present invention preferably contains 0.05 to 3.0% by mass of the dye and / or pigment. If it is added in an amount of more than 3.0% by mass, the production machine is soiled or show-through occurs, which is not preferable. If it is less than 0.05% by mass, the color development becomes weak and a sufficient effect cannot be obtained.

  In the present invention, the coating layer containing a dye and / or pigment preferably contains 10 to 80 parts by mass of a binder based on the total filler. If the amount is less than 10 parts by mass, the amount of the binder is insufficient, so that the strength as a paint is weakened, which is not preferable. On the other hand, if it exceeds 80 parts by mass, the strength as a paint is sufficient, but it is not preferable because phenomena such as blocking and stickiness of the coating layer surface become remarkable. As the binder, for example, various copolymers such as acrylic, styrene, styrene-acrylic, styrene-butadiene can be used as synthetic polymer latex. Furthermore, synthetic binders such as polyvinyl alcohol and carboxymethyl cellulose, starches such as oxidized starch, etherified starch, esterified starch and enzyme-modified starch, natural binders such as modified starch, starch derivatives and casein can also be used. Moreover, various adjuvants, such as a dispersing agent, a water retention agent, an antifoamer, a water-resistant agent, a fungicide, and an antibacterial agent, can also be mix | blended suitably as needed.

  In the present invention, by providing a coating layer containing a filler and a binder on the surface of an anti-counterfeit sheet-like material, for example, various coating layers containing a dye and / or a pigment can be concealed. Since an effect is acquired, it is preferable.

  Further, by providing a coating layer containing a filler and a binder, the penetration of the solvent into the layer containing the dye and / or pigment can be improved, and the eluted dye and / or pigment can be applied to the surface of the sheet. Diffusion and fixing can also be improved. As a result, color development becomes clear and visual recognition becomes easier. Furthermore, it is preferable to provide this coating layer because it is possible to improve the printability of the sheet-like material.

  The filler used in the coating layer containing filler and binder includes kaolin, light calcium carbonate, heavy calcium carbonate, talc, titanium oxide, silica, clay, plastic pigment, colloidal silica, alumina, aluminum hydroxide, calcium sulfate, sulfuric acid. Fillers generally used for paper coating such as barium, zinc oxide, satin white, aluminum silicate, magnesium silicate, calcium silicate, magnesium carbonate and zeolite can be applied.

  In the coating layer containing a filler and a binder, the binder is preferably blended in an amount of 5 to 25 parts by mass with respect to the filler. Binders include various synthetic polymers such as acrylic, styrene, styrene-acrylic, styrene-butadiene, urea, maleic anhydride, ethylene-vinyl acetate copolymer, melamine, and methacrylate, polyvinyl alcohol, carboxymethyl cellulose Synthetic binders such as carboxyethyl cellulose and acrylic acid esters, or starches such as oxidized starch, etherified starch, esterified starch and enzyme-modified starch, modified starch, starch derivatives, casein, soy protein, gelatin and other natural binders can do. Moreover, various adjuvants, such as a dispersing agent, a water retention agent, an antifoamer, a water-resistant agent, a fungicide, and an antibacterial agent, can also be mix | blended suitably as needed.

  In the present invention, when a coating layer containing a dye and / or pigment is provided, a general coating machine such as an air knife coater, blade coater, die coater, roll coater, gravure coater, bar coater or gate roll coater is used. it can.

  In the present invention, when a coating layer containing a dye and / or a pigment is provided, a printing machine may be used so that the coating layer forms characters. Thus, it is preferable to attempt alteration with an organic solvent because the characters can be lifted and the effect of preventing forgery can be further improved.

Examples are described below, but “parts by mass” and “g / m ² ” in the text mean numerical values in terms of solid content.
[Example 1]
70 parts by weight of kaolin, 30 parts by weight of calcium carbonate, 5 parts by weight of starch as binder, SBR latex (trade name “Smartex SN-322” manufactured by Nippon A & L Co., Ltd.) %) Was prepared according to a conventional method (this is referred to as paint A). In addition, water-insoluble and organic solvent-soluble anthraquinone dye particles (trade name “MACROLEX Red Violet R” manufactured by Lanxess Co., Ltd.) having an average particle diameter of 4 μm are prepared in an amount of 1 part by mass with respect to the solid content of the paint. 5 μm of 3 μm water-insoluble and organic solvent-soluble pirarizone dye particles (trade name “Kayaset Flavine FN” manufactured by Nippon Kayaku Co., Ltd.) was added to the solid content of the paint (this is designated as paint B). This paint B was mixed with 40 parts by weight of softwood bleached kraft pulp (NBKP) and 60 parts by weight of hardwood bleached kraft pulp (LBKP) in 400 ml C.I. S. F. The slurry containing the clay, paper strength enhancer, and sizing agent was applied to a base paper having a basis weight of 60 g / m ² using a long web paper machine, and coated with 10 g / m ² using an air knife coater. Further, 15 g / m ² of coating material A was applied onto this coating layer to obtain a forgery-preventing sheet material having a basis weight of 85 g / m ² .

[Example 2]
40 ml of softwood bleached kraft pulp (NBKP), 60 ml of hardwood bleached kraft pulp (LBKP) in 400 ml C.I. S. F. The pulp slurry was adjusted by adding 0.4 parts by weight of a paper strength enhancer, 0.3 parts by weight of a sizing agent, and a sulfuric acid band. 1.0 part by mass of anthraquinone dye particles having an average particle size of 4 μm (manufactured by “MACROLEX Red Violet R” Lanxess Co., Ltd.) and a water-insoluble and organic solvent-soluble pirarizone having an average particle size of 3 μm -Based dye particles (trade name “Kayaset Flavine FN” manufactured by Nippon Kayaku Co., Ltd.) are mixed in an amount of 3.0 parts by mass, and a sheet material for anti-counterfeiting of 95 g / m ² is obtained using a long net paper machine according to a conventional method. It was.

[Example 3]
In the same manner as in Example 2, 40 parts by mass of softwood bleached kraft pulp (NBKP) and 60 parts by weight of hardwood bleached kraft pulp (LBKP) were added to 400 ml C.I. S. F. The pulp slurry was adjusted by adding 0.4 parts by weight of a paper strength enhancer, 0.3 parts by weight of a sizing agent, and a sulfuric acid band. Pigment pigment particles having an average particle diameter of 3 μm (trade name “Sumikaprint Red BF” manufactured by Sumika Color Co., Ltd.) and 3.0 μm pigment pigment particles having an average particle diameter of 4 μm (trade name “Sumikaprint Yellow”). After mixing 5.0 parts by mass of 2RN "Sumika Color Co., Ltd.), 95 g / m < ² > of anti-counterfeit sheet was obtained using a long paper machine according to a conventional method.

[Example 4]
According to a conventional method, a water-based paint (concentration 35% by weight) mainly composed of 70 parts by weight of kaolin, 30 parts by weight of calcium carbonate, 5 parts by weight of starch as a binder, and 15 parts by weight of SBR latex (trade name “Smartex SN-322”) A paint A was prepared. To this, 1 part by mass of water-insoluble and organic solvent-soluble azo dye particles having an average particle diameter of 4 μm (trade name “SPILON RED GEH Special”) with respect to the solid content of the paint and an average particle diameter of 4 μm are water-insoluble and An organic solvent-soluble azo dye particle (trade name “SPILON BLUE 2BNH”) was added in an amount of 5 parts by mass with respect to the solid content of the coating material to prepare a coating material B. A slurry obtained by adding white clay, a paper strength enhancer, and a sizing agent to 40 parts by weight of this paint B, softwood bleached kraft pulp (NBKP), 60 parts by weight of hardwood bleached kraft pulp (LBKP), and a basis weight of 60 g / m using a long paper machine. 10 g / m ^{2 was} coated on one side of the base paper made in No. ² using an air knife coater. Further, 15 g / m ² of coating material A was applied onto this coating layer to obtain a forgery-preventing sheet material having a basis weight of 85 g / m ² .

[Example 5]
According to a conventional method, a water-based paint (concentration 35% by weight) mainly composed of 70 parts by weight of kaolin, 30 parts by weight of calcium carbonate, 5 parts by weight of starch as a binder, and 15 parts by weight of SBR latex (trade name “Smartex SN-322”) A paint A was prepared. The water-insoluble and organic solvent-soluble azo pigment particles (trade name “Monoazo Lake 10G”) having an average particle diameter of 3 μm are 1 part by mass with respect to the solid content of the paint, and the water-insoluble and organic solvent having an average particle diameter of 4 μm. 5 parts by mass of soluble azo dye particles (trade name “Cyanine Blue HS-3” manufactured by Dainichi Seika Co., Ltd.) was added to the solid content of the coating material to prepare coating material B. A slurry obtained by adding white clay, a paper strength enhancer, and a sizing agent to 40 parts by weight of this paint B, softwood bleached kraft pulp (NBKP), 60 parts by weight of hardwood bleached kraft pulp (LBKP), and a basis weight of 60 g / m using a long paper machine. 10 g / m ^{2 was} coated on one side of the base paper made in No. ² using an air knife coater. Further, 15 g / m ² of coating material A was applied onto this coating layer to obtain a forgery-preventing sheet material having a basis weight of 85 g / m ² .

[Example 6]
A synthetic paper made of polypropylene (YUPO FPG # 110, manufactured by YUPO Corporation) was prepared, and 10 g / m ^{2 of the} coating material B used in Example 4 was applied thereto using a bar coater. Further, 15 g / m ^{2 of the} coating material A used in Example 4 was applied onto the coating layer to obtain a forgery-preventing sheet.

[Example 7]
A film sheet made of polyethylene terephthalate (thickness: 110 μm) having a hydrophilic treatment on the surface was prepared, and the coating material B used in Example 5 was applied at a solid content mass of 10 g / m ² using a bar coater. Further, 15 g / m ^{2 of} coating material A used in Example 5 was applied onto this coating layer to obtain a forgery-preventing sheet.

[Example 8]
A polyester nonwoven fabric having a basis weight of 50 g / m ² was prepared, and the coating material B used in Example 5 was coated on the roll coater with a solid content mass of 10 g / m ² . Further, 15 g / m ^{2 of} coating material A used in Example 5 was applied onto this coating layer to obtain a forgery-preventing sheet.

[Comparative Example 1]
In the same manner as in Example 1, 40 parts by mass of softwood bleached kraft pulp (NBKP) and 60 parts by mass of hardwood bleached kraft pulp (LBKP) were added to 400 ml C.I. S. F. The pulp slurry was adjusted by adding 0.4 parts by weight of a paper strength enhancer, 0.3 parts by weight of a sizing agent, and a sulfuric acid band. To this, a phthalocyanine-based cationic direct dye (trade name “Turquoise K-GL liq” manufactured by Clariant Co., Ltd.) (water-soluble and insoluble in organic solvent) was added internally, and 95 g / A sheet of m ² was made.

[Comparative Example 2]
A synthetic phthalocyanine-based cationic direct dye (trade name “Turquoise K-GL liq”) is formed on a synthetic paper (Yupo FPG # 200, manufactured by Oji Oil Chemical Co., Ltd.), a biaxially stretched film formed mainly of polypropylene resin. A coating (mixture C) manufactured by Clariant Co., Ltd.) was applied at 15 g / m ² to obtain a sheet.

[Comparative Example 3]
A film sheet (thickness: 110 μm) made of polyethylene terephthalate with a hydrophilic treatment applied to the surface was prepared, and 15 g / m ^{2 of the} same paint C as in Comparative Example 2 was applied thereto with a bar coater to obtain a sheet-like material. .

[Comparative Example 4]
A polyester nonwoven fabric having a basis weight of 50 g / m ² was prepared, and the same paint C as in Comparative Example 2 was applied at 15 g / m ² with a roll coater to obtain a sheet-like material.

  As representative organic solvents, ethyl acetate, toluene, methyl ethyl ketone, isopropyl alcohol, and benzene were dropped on the surfaces of the sheet-like materials obtained in Examples and Comparative Examples. Visual observation was performed. In addition, the case where water was dripped for reference was also observed visually. The above observation results are shown in Tables 2 and 3. The color development was evaluated as ◎ for remarkable color development, ○ for normal color development, and × for those that did not change. In addition, it confirmed that the same result was obtained for visible light used for evaluation both under natural light and under illumination with an incandescent bulb.

（表３）

(Table 2)

(Table 3)

  The coated surface of Example 1 and the paper surfaces of Examples 2 and 3 appear to be lightly colored in the hue of the dye or pigment used because the dye or pigment particles are uniformly dispersed. . However, when observed using a magnifying glass, it can be seen that the particles are distributed in a state of particles.

  When various organic solvents are dropped on the surface of the anti-counterfeit sheet-like material obtained in these examples, the contained dye or pigment is eluted and diffuses to the surroundings by capillary action. When the dropping site is observed after the solvent is volatilized, for example, in the dropping of ethyl acetate, red spots are confirmed in Example 1, Example 4, and Example 6, and in Examples 2 and 3, a red circle is observed. However, blue spots were confirmed in Example 5, Example 7, and Example 8. In the dropping of toluene, yellow spots in yellow in Example 1, Example 2, Example 4, and Example 6, red circles in Example 3, blue in Examples 5, 7, and 8. The circle was confirmed. In the dropping of methyl ethyl ketone, yellow spots in yellow in Example 1, Example 4 and Example 6, red circles in yellow in Example 2, red circles in Example 3, Example 5 and Examples 7. In Example 8, blue spots were confirmed in red. In the dropping of isopropyl alcohol, yellow circles in Example 1, Example 2, Example 4, and Example 6, yellow spots in red in Example 3, and Example 5, Example 7, and Example 8 were used. Red spots were confirmed. In the dropping of benzene, yellow circles were observed in Example 1, Example 2, Example 4, and Example 6, red and yellow spots were observed in Example 3, and Example 5 “Example 7 and Example 8”. Blue spots were observed in red, and no change was observed in any of the examples when water was dropped, and Comparative Examples 1 to 4 were all organic solvents used in the test. , And no change was observed with respect to the dripping of water.

The anti-counterfeit sheet material of the present invention has the following effects.
(1) Passports, traveler's checks, checks, bills, and identification cards often use oil-soluble inks to describe variable information such as name and amount, and passports and identification cards protect photographs. Sheets are often affixed. According to the present invention, traces when attempting to falsify variable information using oil-soluble ink using a solvent or to replace a photo are visually visible under visible light without using a special instrument. Therefore, the anti-counterfeit sheet material of the present invention can be suitably used for such anti-counterfeit applications.
(2) In addition, taking advantage of the fact that fraud can be done using solvent and label peeling, and the reattached traces can be easily seen, proof of brand products, sealing of electronic devices (inside credit card readers, etc.) It can also be used suitably for brand protection label applications such as the purpose of preventing unauthorized rewriting of specifications).
(3) The dye and / or pigment used in the present invention can be appropriately selected according to the solvent expected to be used for falsification. In addition, by using two or more kinds of dyes and / or pigments with different solubility parameters at the same time, it can cope with a wide range of solvents, and due to the difference in solubility, the traces of tampering are not constant, such as circular or speckled Therefore, a higher anti-counterfeit effect can be obtained.

: It is sectional drawing which showed an example about the sheet material for forgery prevention of this invention. The base material contains a water-insoluble and organic solvent-soluble dye and / or pigment. : It is sectional drawing which showed an example which showed the sheet-like material for forgery prevention of this invention. A coating layer containing a pigment is provided on the substrate. : It is sectional drawing which showed an example which showed the sheet-like material for forgery prevention of this invention. A coating layer containing a pigment is provided on the sheet-like material of FIG.

Explanation of symbols

1. Base material 2. 2. Dye or pigment particles Pigment coated substrate

Claims (7)

  Forgery prevention characterized in that it contains one or more water-insoluble and organic solvent-soluble dyes and / or pigments, and the trace of tampering caused by the dropping of one or more organic solvents is visible under visible light. Sheet material.   A coating layer containing one or more water-insoluble and organic solvent-soluble dyes and / or pigments is present on at least one side of the sheet-like material, and visible traces of tampering due to the dripping of one or more organic solvents are visible under visible light. A forgery-preventing sheet-like material characterized by being made possible.   3. A forgery-preventing sheet material according to claim 1 or 2, wherein a coating layer containing a filler and a binder is present.   The forgery prevention according to any one of claims 1 to 3, wherein when two or more kinds of organic solvents having different solubility parameters are dropped, in any case, traces of the dropping can be visually recognized under visible light. Sheet material.   The sheet material for preventing forgery according to any one of claims 1 to 4, wherein the sheet material is made of wood pulp as a main raw material.   The anti-counterfeit sheet-like material according to any one of claims 1 to 5, wherein the water-insoluble and organic solvent-soluble dye is an azo dye, an aminoketone dye, or a coumarin dye. The anti-counterfeit sheet-like material according to any one of claims 1 to 5, wherein the water-insoluble and organic solvent-soluble pigment is an azo pigment or a phthalocyanine pigment.

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