JP2010065336A - Chips and anti-counterfeit paper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anti-counterfeit material, capable of easily discriminating true or false without using a special tool or device and also having a high anti-counterfeit effect. <P>SOLUTION: The chips of which base material is provided with a temperature responsive coated layer of changing its hue reversibly by the change of temperature, are produced. Addition of the chips to the anti-counterfeit paper allows discrimination the color-changing effect of the chips by the change of temperature to enable the discriminatement of true or false easily. By providing two kinds or more of the temperature responsive coated layers, higher effects can be obtained. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a material having an authentication function. More specifically, the present invention relates to a strip used for anti-counterfeit paper, and in particular, a strip that can easily and highly judge authenticity by changing to a completely different hue due to a change in temperature, and Relates to anti-counterfeit paper containing

Securities with a monetary value such as banknotes, gift certificates, stock certificates, bonds, checks, lotteries, etc. have various anti-counterfeiting measures so that they are not easily counterfeited or altered. The same applies to admission tickets for the Olympics, passports, and other various identification cards.

By the way, due to recent technological advances, the above-mentioned securities are printed by a multicolor printer, copied by a color copier, or a color printer that captures an image with a digital scanner linked to a personal computer. Forgery is increasing in many ways, such as by printing. Recently, even for home printers, it has become possible to produce counterfeit products relatively easily because the resolution, hue, and the like can be reproduced so precisely that they cannot be distinguished from the real ones. In this way, the increase in counterfeiting using digital devices has become a problem, and the damage caused by the counterfeiting has become familiar.

From the background as described above, various proposals have been made as techniques for preventing counterfeiting using digital devices. For example, Patent Document 1 proposes an anti-counterfeit paper having an intermediate hue that is difficult to be reproduced by a color copying machine or the like and having strips that are colored by ultraviolet irradiation. Patent Document 2 proposes a forgery-preventing paper in which a strip in which layers that cause a color change depending on the viewing angle are stacked is formed. In Patent Document 3, a security element having a hologram is proposed, and pearl pigment printing, ultraviolet fluorescent printing, and a forgery-preventing paper using a substrate subjected to these as a thread after being processed are proposed. .

In addition, holograms and pearl pigments have metallic luster and pearl luster, and the metallic luster and pearl luster can be reproduced by printing with a color copier or by outputting an image read with a digital scanner with a color printer. Can not counterfeit. For example, in the case of Patent Document 4, the present applicant forms a partial coating layer mainly composed of a pearl pigment and an adhesive on the surface of a base paper to obtain a forgery-preventing paper. Proposed to get prevention printed matter. Moreover, in patent document 5, it proposed about the strip which provided the pearl luster.

As described above, various techniques for preventing forgery have been proposed and adopted. However, even if we establish anti-counterfeiting technology, new anti-counterfeiting means are being created one after another, so new anti-counterfeiting technology is always in demand to counter new emerging counterfeiting means. It has been. Furthermore, as a result of being easily counterfeited by a method using a printing machine, scanner, etc. as described above, the damage caused by the counterfeit is also familiar, so that forgery can be easily determined without using special equipment. Prevention technology is needed. For example, in a store where a gift certificate or the like is purchased, there is a demand for a technique that allows a store clerk to easily determine the authenticity of a gift certificate that has been brought in on the spot.

JP 2000-73298 A Japanese Patent Laid-Open No. 2005-15963 JP 2006-528369 A JP-A-6-313298 JP 7-243193 A

  In order to easily determine the authenticity, it is desirable not to use a special instrument such as a black light or a magnetic detection device, and a security material that can easily determine the authenticity is effective. An object of the present invention is to provide a new anti-counterfeiting material that is effective as a means for simply determining authenticity as a new anti-counterfeiting material.

  As a result of intensive studies on the above problems, the present inventor has completed the present invention by providing a layer whose hue changes with a change in temperature on a base material and obtaining a small piece of the layer. Furthermore, by forging the strips on paper, it was possible to obtain anti-counterfeit paper having an unprecedented effect.

That is, the invention according to claim 1 of the present invention is a strip in which a temperature-responsive coating layer whose hue changes as the temperature changes is provided on at least one side of the substrate.

The invention according to claim 2 of the present invention is the strip according to claim 1, wherein the hue of the temperature-responsive coating layer reversibly changes as the temperature changes.

The invention according to claim 3 of the present invention is the strip according to claim 1 or 2, wherein the base material is paper.

  The invention according to claim 4 of the present invention is the strip according to claim 1 or 2, wherein the substrate is a transparent multilayer film.

The invention according to claim 5 of the present invention is the strip according to any one of claims 1 to 4, wherein a pearl luster layer is provided on the substrate.

The invention according to claim 6 of the present invention is the strip according to any one of claims 1 to 5, wherein an ultraviolet absorbing layer is provided on the substrate.

The invention according to claim 7 of the present invention is the strip according to any one of claims 1 to 6, wherein the temperature at which the hue changes is in the range of -4 ° C to 58 ° C.

The invention according to claim 8 of the present invention is the strip according to any one of claims 1 to 6, wherein the temperature at which the hue changes is in the range of 25 ° C to 33 ° C.

In the invention according to claim 9 of the present invention, there are two or more types of temperature-responsive coating layers that exhibit the same hue at room temperature but differ in hue at any temperature other than room temperature, on one side of the substrate. Or the strip according to any one of claims 1 to 8, wherein the strip is present separately on both sides of the substrate.

In the invention according to claim 10 of the present invention, there are two or more types of temperature-responsive coating layers on one surface of the substrate that exhibit different hues at room temperature but have the same hue at any temperature other than room temperature. Or the strip according to any one of claims 1 to 8, wherein the strip is present separately on both sides of the substrate.

An invention according to an eleventh aspect of the present invention is a forgery-preventing paper, characterized in that the strip according to any one of the first to tenth aspects is used.

The invention according to claim 12 of the present invention is the anti-counterfeit paper according to claim 11, wherein two or more kinds of strips showing different hue changes are used.

The invention according to claim 13 of the present invention is characterized in that two or more types of strips exhibit the same hue at room temperature but differ in hue at any temperature other than room temperature. It is.

The invention according to claim 14 of the present invention is the anti-counterfeit paper according to claim 12, wherein two or more types of strips exhibit different hues at room temperature but have the same hue after heat change. is there.

The anti-counterfeit paper using strips according to the present invention has the following effects, and is preferably used as an anti-counterfeit measure for banknotes, gift certificates, passports, stock certificates, identification cards, cards, admission tickets, stock certificates, checks, etc. can do.
(1) It is possible to easily determine the authenticity by visually observing the discoloration effect of the strip due to the temperature change.
(2) The pearl luster strip has a color shift effect in which the hue continuously changes depending on the viewing angle under visible light, and it can be easily determined by visual inspection.
(3) The effects (1) and (2) can be simultaneously confirmed by visual observation, and since a special technical instrument is not required for this detection, authentication can be easily determined.

The first embodiment of the present invention is a strip obtained by providing a temperature-responsive coating layer whose hue changes with temperature at least on a base material and then sizing it. Since the hue of the strip changes due to a change in temperature condition, it is possible to determine the authenticity by visual observation. For example, if it is designed so that when the strip is touched with a finger, the hue of the strip changes in response to the heat of the body temperature, anyone can easily identify the authenticity.

The material used for the temperature-responsive coating layer is a conventionally known electron-donating color-forming organic compound, a compound having a phenolic hydroxyl group, an alcohol, an ether, an ester, or a ketone. It is a thermochromic material consisting of three components with a selected organic solvent. Electron-donating color-forming organic compounds include, for example, diphenylmethane phthalides, triphenylmethane phthalides, phenyl indolyl phthalides, indolyl phthalides, diphenyl methane azaphthalides, phenyl indolyl azaphthalides, Fluoranes, styrinoquinolines, azomethines, leucooramines, spiropyrans, rhodamine lactams, diazarhodamine lactones, naphtholactams, phenothiazines, triazenes, spirophthalanthanthenes is not. Examples of the compound having a phenolic hydroxyl group include monophenols and polyphenols, and specific examples thereof include those described in JP-A-49-78682 and JP-A-61-9488. It is not limited to these. A commercially available thermochromic material can be used.

As the thermochromic material, for example, a material encapsulated in a microcapsule having a particle size of 0.1 to 50 μm is preferably used. There are three types of color change depending on the temperature of the thermochromic material: one that changes reversibly, one that changes quasi-reversibly, and one that changes irreversibly, depending on the material selected. .

In addition to the thermochromic material, the paint forming the temperature-responsive coating layer includes a melamine resin, urea resin, phenol resin, alkyd resin, petroleum resin, polyester resin, polyurethane resin, polyvinyl chloride resin as a binder, Polyvinyl acetate resin, polyamide resin, polyacrylate resin, nitrocellulose, cyclized rubber, chlorinated rubber, etc. can be used alone or as a mixture, and the binder is toluene, ethyl acetate, methyl ethyl ketone, acetone, gasoline, etc. It is used by dissolving in an organic solvent such as petroleum solvent. Other binders include rosin-modified phenolic resins dissolved in drying oil (linseed oil, etc.) and high-boiling solvent for offset printing ink vehicles, or SBR latex, MBR latex, vinyl acetate emulsion, acrylic acid. Water-based binders such as ester emulsions and polyvinyl alcohol resins can be used.

Examples of changes in the hue of the temperature-responsive coating layer include the following. One is colored below the temperature at which the hue changes, and changes to white when the hue change temperature is exceeded.Specifically, there are those that change from black to white, those that change from blue to white, etc. is there. Others are colored below the hue change temperature and change to a color different from the original hue when the hue change temperature is exceeded, specifically those that change from black to blue, or green to yellow And the like that change. Of course, other hue changes can be designed. The design of the hue change has a wide selectivity depending on the selection of the developer and the combination with the colored dye and / or the pigment, and can be appropriately selected and used according to the purpose.

Moreover, it is preferable that a temperature-responsive coating layer changes reversibly with changes in temperature. This is because even if the hue has changed once, it can be used repeatedly as long as it can return to the original hue.

As the base material used in the present invention, paper, synthetic paper, non-woven fabric, film and the like are used. When paper is used as the base material, it is preferable because the adhesive strength with the paper is high when the paper is made into paper after being cut into pieces. Moreover, when a nonwoven fabric and a film are used as a base material, it is preferable at the point which can employ | adopt a thin thing. In addition, it is preferable to employ a transparent film because the hue can be changed by the influence of the temperature-responsive coating layer even on the surface where the temperature-responsive coating layer is not provided, as will be described later.

The paper used for the base material is mainly wood pulp that is generally used for papermaking, and if necessary, modified pulp such as non-wood pulp, cationized pulp, mercerized pulp, etc., microfibrillated Recycled fibers such as pulp, rayon, vinylon, nylon, acrylic, and polyester, semi-synthetic fibers, and synthetic fibers are mixed as appropriate. Fillers, paper strength enhancers, sizing agents, fixing agents, yield improvers, freeness improvers In addition, papers made by appropriately adding general papermaking chemicals such as antifoaming agents, dyes and pigments can be used. In particular, it is preferable that the degree of sizing and the wet paper strength are large in consideration of the coating suitability and water resistance of a thermochromic material and a pearl pigment or the like when the strip is produced. The synthetic paper used for the base material is made of, for example, polypropylene, polystyrene, polyethylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyethylene terephthalate, polybutylene terephthalate, polyamide, etc. Although the manufactured thing etc. are mentioned, it is not limited to these. Examples of the nonwoven fabric used for the base material 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. However, it is not limited to these. Examples of the film used for the substrate include PET, polyester, polyethylene, polypropylene, cellophane, nylon, polyvinyl alcohol, polyvinyl chloride, and polycarbonate, but are not limited thereto. In addition, as a base material, intensity | strength and rigidity required when applying each coating material are required, and the thing of about 20-50 g / m < ² > is preferable in the case of paper or a synthesis | combination. In the case of a film or a nonwoven fabric, a thing of about 6-45 g / m < ² > is preferable.

The method of providing the temperature-responsive coating layer on the substrate can be performed using a known coating technique. Examples of the coating method include, but are not limited to, a rod coater, a bar coater, an air knife coater, a blade coater, a gravure coater, a die coater, a gate roll coater, a size press coater, and various printing machines.

The temperature-responsive coating layer provided on the substrate is preferably provided on both sides of the substrate. When the obtained strip is engraved on the anti-counterfeit paper, it is impossible to predict which side of the strip will be exposed on the surface of the paper, so it is efficient to provide a temperature-responsive coating layer on both sides. Because it is good.

The coating amount of the temperature-responsive coating layer provided on the substrate is preferably ² to 19 g / m ² although it depends on the paint component. If it is less than 2 g / m ² , the color development is weak and it is difficult to confirm a change in hue, and it is useless because the intensity of color development does not increase by coating over 19 g / m ² .

The base material may be colored to such an extent that the performance of the present invention is not affected. When strips made of the colored base material are applied to anti-counterfeit paper, it is easy to find a location where the strips are present, and as a result, authenticity determination is facilitated. The method for coloring the substrate is not particularly limited, and existing dyes and coloring pigments can be used. However, when the color is dark, it is not preferable because the position may overlap with the printing information, money amount information, or the like of the anti-counterfeit paper, so that necessary information cannot be determined.

In the present invention, a fine piece can be obtained by fragmenting a base material provided with a temperature-responsive coating layer. The strips may be cut into small pieces so as to have a shape, length, and area according to the purpose. As the shape, for example, any shape such as a circle, an ellipse, a square, a rectangle, a rhombus, a triangle, a star, a crescent, and a polygon can be selected. Although there is no particular designation as a method of fragmentation, a method using a shredder, a method of punching using a tooth profile of the above shape, or a method of cutting a substrate into long and thin pieces with a micro slitter is adopted. it can. The standard of the size of the strip is preferably about 0.2 to 10 mm in length, but the strip is preferably large in order to easily determine the change in hue.

Moreover, in this invention, what includes a pearl luster pigment as a base material is preferable. When such a base material is used, it is possible to combine both the color shift effect under reflected light and the effect of hue change due to temperature change, and it is difficult to forge the complicated hue change. The color shift effect means that the color changes as the reflected light gradually shifts when the viewing angle with the object is changed. For example, when a transparent multilayer film having pearl luster is used, a higher anti-counterfeit effect can be obtained.

As the base material containing the pearl luster, for example, natural pearl essence, mica powder, basic carbonate, titanium oxide coated mica powder, metal oxide coated mica powder, paper coated with bengara coated mica powder, etc. are used. it can. Or the pearl luster paper which sprinkled the pearl pigment by the spray apparatus to the base paper introduce | transduced by Unexamined-Japanese-Patent No. 5-222700 is mentioned. The method for producing such pearl pigments is not particularly limited, and conventionally known production methods (for example, JP-B-53-47375, JP-B-54-34010, JP-A-58-149959, etc.) Those obtained by the method described in the publication can be used. In addition to this, examples of the base material containing the pearl luster include a material obtained by kneading a pearl pigment into a resin to form a film.

The transparent multilayer film is a film obtained by laminating a plurality of polymers having two or more different refractive indexes, and exhibits a pearly luster due to a light interference phenomenon. For example, a polymer obtained by repeatedly laminating 100 or more layers of a high refractive index and a low refractive index can be used. It is known that pearl luster cannot be reproduced by a copying method such as color copying or reading with a digital scanner and outputting with a printer because it has the characteristic of shining in an iris color when viewed with specular reflection light. Therefore, by using the transparent multilayer film, not only a color shift effect but also such a copy prevention effect can be imparted. Furthermore, when the colored coating layer provided on the transparent multilayer film having pearly luster is viewed through the film, a new hue in which the original hue of the film is mixed is generated. As described above, in the present invention, since the hue of the colored coating layer also changes due to temperature change, the color shift effect becomes very complicated, and as a result, a high anti-counterfeit effect can be obtained.

Further, in the present invention, the anti-counterfeiting effect similar to that when using the pearl gloss paper or the transparent multilayer film is obtained in order to exert a color shift effect even by providing a coating layer having pearl gloss on the substrate. be able to. When the transparent multilayer film having the pearly luster described above is used, the hue changes depending on the thickness and total thickness of each layer. The method of providing a layer also has the advantage that a wide variety can be increased by changing the pigment at a lower cost than the production of a film.

Examples of the pigment that can be used in the coating layer having pearly luster include natural pearl essence, mica powder, basic carbonate, titanium oxide-coated mica powder, metal oxide-coated mica powder, and Bengala-coated mica powder. The method for producing such a pearl pigment is not particularly limited, and conventionally known production methods (for example, Japanese Patent Publication Nos. 53-47375, 54-34010, 58-149959, etc.) Can be used. The pearl pigment is mixed with an adhesive and applied to the substrate. The adhesive is not particularly limited as long as the pearl pigment can be fixed to the base material. For example, an aqueous dispersion of binder particles combined with an ultrafine filler can be used. Colloidal silica, alumina sol, etc. can be used as ultrafine fillers, and acrylic polymer emulsion, silane group addition olefin polymer emulsion, polyvinyl alcohol, modified polyvinyl alcohol, ethylene-vinyl acetate copolymer emulsion, etc. as binders. Can be used. The coating layer having pearly luster can be provided by using a known coating technique as described above, and the coating amount is preferably such that the performance of the present invention is not impaired, and is about ² to 12 g / m ^2. Good. If it is less than 2 g / m ^2, it is difficult to obtain a pearly luster effect, and if it is applied in excess of 12 g / m ² , a corresponding effect cannot be obtained, which is useless. However, when a coating layer having pearly luster is provided on the substrate, care must be taken so as not to affect the effect of the hue change of the present invention. Therefore, when a coating layer having a pearly luster is provided on the temperature-responsive coating layer, the coating amount should be adjusted according to the amount of the temperature-responsive coating layer. About ² to 5 g / m ² is preferable.

In the present invention, a resin layer having ultraviolet absorbing ability can be provided on the substrate. By providing this, since the light resistance of the material used for the temperature-responsive coating layer can be improved, it can be suitably used even when the usage method is such that it is distributed or stored for a long period of time. . In order to prevent the photo-degradation of the temperature-responsive coating layer, the resin layer having the UV-absorbing ability is used so that the UV-absorbing layer is present on the side that receives light from the temperature-responsive coating layer. Good. For example, the ultraviolet absorbing layer, the temperature-responsive coating layer, and the base material are used in this order from the side that is exposed to light. Alternatively, the order may be the ultraviolet absorbing layer, the base material, and the temperature-responsive coating layer, or the base material, the ultraviolet absorbing layer, and the temperature-responsive coating layer. However, when the base material is chopped into paper and made into paper, it is difficult to make only one side of the base material into the side where the light hits. It is preferable to provide it.

As the resin used for the resin layer having ultraviolet absorbing ability, a known resin can be used. In particular, transparent resins such as benzophenone, benzotriazole, and benzoate are preferably used. The reason is that the ultraviolet absorbing layer is functionally disposed on the side that is exposed to light rather than the temperature-responsive coating layer. Therefore, it is not preferable to use a material such as titanium oxide that imparts opaqueness at the same time as the ability to absorb ultraviolet rays because it may hinder the visibility of the hue change effect. Since the ultraviolet absorbing layer should be provided to such an extent that the performance of the present invention is not impaired, the coating amount is set to 0.4 to 3.0 g / m ² . As the coating method, the above-described known technique may be used.

In the present invention, the temperature at which the hue of the material used for the temperature-responsive coating layer changes is preferably in the range of −4 ° C. to 58 ° C. And it is preferable to set the change temperature to 25-33 degreeC especially. By using a material that falls within this temperature range, it is possible to change the hue even at a human body temperature, so it is possible to easily determine the authenticity without requiring a special device such as a cooling device or a heating device. . When the hue change temperature is less than 25 ° C., it is necessary to use some cooling means in order to confirm the hue change in a season or place where the air temperature is 25 ° C. or higher. In that case, it may be cooled using a simple object such as a cooling spray, a cooling sheet, an ice pack, or a cooling machine. However, if the hue change temperature is less than −4 ° C., a special cooling device is required, and as a result, it is not possible to easily determine the authenticity. Further, when the hue change temperature is higher than 33 ° C., it is difficult to change at about the surface temperature of a human hand, so some heating means is required. At this time, it is preferable to use simple means as much as possible. For example, a change in hue can be confirmed by using a stove, a heater, a warmer, heat of a fluorescent lamp, a hot water bottle, a thermal sheet, or the like. However, if the hue change temperature is higher than 58 ° C., a special heating device is required, and it may not be possible to easily perform authentication determination, which is not preferable.

In the present invention, two or more types of temperature-responsive coating layers may be provided. By providing two or more different layers, the effects of each temperature-responsive coating layer can be combined, so that a complex hue change can be obtained. The two or more types of temperature-responsive coating layers may be provided on one side of the substrate. For example, it is good to provide so that two or more types of temperature-responsive coating layers may form arbitrary patterns in the single side | surface of a base material. Thereby, the effect that the pattern which cannot be visually recognized in a certain temperature zone comes to be visually recognized in another temperature zone is acquired. Specifically, two or more types of temperature responsiveness exhibiting the same hue at room temperature but showing different hues when changed to any temperature other than room temperature are arranged on the substrate so as to form a stripe. Thus, the same color appears at room temperature, but the stripe pattern can be confirmed only by changing the temperature other than room temperature. In this way, not only the hue changes but also various design properties can be given depending on the type of pattern. Therefore, since it becomes possible to give unique characteristics according to the application and the user, it is possible to obtain a strip having excellent practicality and a high anti-counterfeit effect. When forming such an arbitrary pattern, it is good to use a printing machine instead of a coating machine. The “normal temperature” in the present invention refers to a daily temperature, and specifically refers to a temperature of about 12 ° C. to 28 ° C., although it varies depending on the season, time zone, and location.

Or you may provide one or more types of different temperature-responsive coating layers in the front and back of a base material. When the base material provided with the coating layer is cut into pieces and paper is made, it is difficult to make the paper so that only one side of the base material is visible to humans. It is preferable to provide different temperature-responsive coating layers on the front and back sides and make the paper on paper, so that both sides can be visually recognized by humans, and two or more hue change effects can be obtained as a forgery prevention effect.

As another example, two or more types of temperature-responsive coating layers that exhibit different hues at room temperature but exhibit the same hue after changing to any temperature other than room temperature are formed on the substrate so as to form an arbitrary pattern. By providing them on the front or back of the substrate, it is possible to obtain an effect that the pattern and hue confirmed at room temperature become invisible after the temperature change. This is also effective as an anti-counterfeit effect and a design effect.

The second aspect of the present invention is a forgery-preventing paper in which a strip according to the first aspect of the present invention is applied to paper. In order to apply the strip to the anti-counterfeit paper, it is necessary to bond the strip to the paper. For this purpose, it is preferable to provide an adhesive layer on the surface opposite to the temperature-responsive coating layer provided on the strip substrate and / or on the temperature-responsive coating layer. As the adhesive layer, an adhesive that is not necessary for cold water but is soluble in hot water may be used. This is because the temperature-responsive coating layer may dissolve if dissolved in the wet part of the paper machine, so it must be insoluble in cold water, and swells or dissolves with the heat of the drying process to adhere to the paper. This is because properties are necessary. Water-soluble binders are effective as those having such properties. For example, starch-based, methylcellulose-based, carboxylated cellulose-based, hydroxyethylcellulose-based, polyvinylalcohol-based, polyvinylpyrrolidone-based, vinylethylether-maleic anhydride copolymer Of the system, polyacrylic acid type, polyethylene oxide type, etc., it is preferable to use those that are insoluble in cold water but soluble in hot water. This adhesive layer is provided with a coating amount of ² to 10 g / m ² per side using a known coating machine such as an air knife coater or a roll coater. This adhesive layer may be provided on one side of the base material, but it is effective to provide the adhesive layer on both sides of the base material in order to prevent the strips from falling off the paper. When the adhesive layer is provided, the adhesive layer may be provided directly on the strip, but the work efficiency is better when the adhesive layer is provided on the substrate before the strip.

A well-known method is employ | adopted as a method of providing a strip in paper. For example, the fine pieces may be suspended in water and added to the paper stock, and the paper may be made in a general paper making process. However, it is more efficient and practical to engrave the strips so that they are widely distributed near the paper surface rather than inside the paper. Examples of the method of unevenly distributing the strips near the surface include, for example, a method in which the strips are uniformly sprinkled on a paper web on a long paper machine using an apparatus proposed in Japanese Patent Laid-Open No. 7-145600, As proposed in 207599, there is a method of including a strip in the outermost layer of the multilayer paper.

In the present invention, there is no particular limitation on the raw material of the paper to which the fine pieces are imparted. For example, wood pulp, non-wood pulp such as hemp, cotton, straw, etc. are appropriately blended and beaten, and if necessary, synthetic fibers A mixture of semi-synthetic fibers, inorganic fibers and the like can be used. Add commonly used papermaking chemicals such as fillers, paper strength enhancers, sizing agents, fixing agents, yield improvers, drainage improvers, antifoaming agents, dyes, pigments, etc. Prepare. The beating degree is 150 to 580 mLc. s. f. It is better to make paper at a degree. A general paper machine may be used as the paper making method, and the basis weight is preferably about 30 to 160 g / m ² although it depends on the purpose of use.

In the present invention, forgery prevention paper using two or more types of strips may be used. By forging two or more types of strips having different colors or by forging two or more types of strips having different hue changes, forgery is further difficult, and the forgery prevention effect is enhanced. For example, if two or more types of strips have the same hue at room temperature but differ in hue when they change to a temperature other than room temperature, the anti-counterfeit paper obtained using them appears to be the same color at room temperature. For the first time, it becomes possible to determine the presence of two or more types of strips. Similarly, even if two or more types of strips exhibit different hues at room temperature but are designed to have the same hue when changing to a temperature other than room temperature, the resulting anti-counterfeit paper can be any The hue becomes one at the temperature, and forgery can be determined.

[Example 1]
40 parts by weight of softwood bleached kraft pulp and 60 parts by weight of hardwood bleached kraft pulp as base materials were 380 mLc. s. beat to f, 0.4 parts by weight of paper strength enhancer (trade name “Polystron 117”, manufactured by Arakawa Chemical Co., Ltd.), sizing agent (trade name “Size Pine GF”, Arakawa Chemical Industries) A paper stock was prepared by adding 1.0 part by mass and 2.0 parts by mass of a sulfuric acid band, and a base paper having a basis weight of 35 g / m ² was made using a long net paper machine. On one side of this base paper, a temperature gravure ink (trade name “Chromi Color Black to White“ Temperature Type 27 ”, manufactured by Matsui Dye Chemical Co., Ltd.) as a temperature responsive coating layer is 8 g / m with a gravure coater. ^Two coats were applied. The other side of the base paper was coated with 4 g / m ² of 5% by weight aqueous solution of polyvinyl alcohol (Kuraray Poval 117, manufactured by Kuraray Co., Ltd.) using an air knife coater. This was punched into a 5 mm × 6 mm rectangle with a punching machine to obtain strips. This strip is black at room temperature set to 25 ° C. When it is heated to 27 ° C, the hue changes within 30 seconds and turns gray, and when it is heated to 30 ° C, it turns completely white. did. When the temperature was returned from 30 ° C. to 25 ° C., the original black color was restored in about 20 seconds.

[Example 2]
A transparent multilayer film (trade name “MLF16.5”, manufactured by Teijin DuPont Co., Ltd.) having a thickness of 16 μm is used as a base material, and a temperature gravure ink (trade name “chromicolor black to” is used as a temperature-responsive coating layer on one side. White “Temperature Type 27”) was applied with a gravure coater at 8 g / m ² . The other side of the base paper was coated with 4 g / m ² of 5% by weight aqueous solution of polyvinyl alcohol (Kuraray Poval 117, manufactured by Kuraray Co., Ltd.) using an air knife coater. This was punched into a 5 mm × 6 mm rectangle with a punching machine to obtain strips. The resulting strip has a black color in the temperature-responsive coating layer under 25 ° C conditions, and when viewed from the film surface side, the color shift effect that changes from green to red depending on the angle is clearly visible. It was. When the temperature was raised to 30 ° C., the temperature-responsive coating layer turned white, and the original pink color of the film could be seen. Although the original effect of the film did not change, the hue on the back side changed, so that the hue and effect of the film itself seemed to change, and a unique design could be obtained. When the temperature was returned from 30 ° C. to 25 ° C., the temperature-responsive coating layer returned to black.

[Example 3]
A urethane resin binder (trade name “RAMIC F220”, manufactured by Dainichi Seika Kogyo Co., Ltd.) was diluted to a solid content of 15%. A pearl pigment (trade name “Iriodin 225”, manufactured by Merck & Co., Inc.) was added and dispersed in this solution so that the total solid content was 25%. The transparent PET film of paint thickness 16μm was to create a film with a pearl luster layer was 10g / m ² coated by a gravure coater to one side of the (trade name "Lumirror 16S28", Toray Industries Co., Ltd.). Subsequently, a temperature gravure ink (trade name “chromi color black to white“ temperature type 27 ”) was applied with a gravure coater at 8 g / m ² so as to cover the pearly luster layer. The other side of the base paper was coated with 4 g / m ² of 5% by weight aqueous solution of polyvinyl alcohol (Kuraray Poval 117, manufactured by Kuraray Co., Ltd.) using an air knife coater. In the film thus obtained, the temperature-responsive coating layer exhibited a black color under the condition of 25 ° C., and when viewed from the film surface side, the blue pearl luster was conspicuous. The obtained film was punched into a 5 mm × 6 mm rectangle with a punching machine to obtain strips. When this strip was heated to 30 ° C., the temperature-responsive coating layer turned white. At first glance, the strip appeared white, but depending on the angle, it was also possible to confirm blue or yellow pearl luster. Although the hue of the pearly luster layer did not change, it utilized the characteristic that the pearly luster was conspicuous when the lightness of the hue on the back surface was low, and a unique design could be obtained. When the temperature was returned from 30 ° C. to 25 ° C. again, the temperature-responsive coating layer returned to black, and the strips showed a blue pearl luster.

[Example 4]
From the temperature-responsive coating layer side of the film obtained in Example 2, 1 g of a resin (trade name “ULS-1935”, manufactured by Yushi Kogyo Co., Ltd.) having ultraviolet absorbing performance was obtained with a gravure coater. After coating with / m ^2, it was punched into a 5 mm × 6 mm rectangle with a punching machine to obtain strips.

Both the strips obtained in Example 2 and Example 4 were subjected to a light resistance tester (ATLAS Ci4000, manufactured by Toyo Seiki Co., Ltd.) and continuously irradiated with ultraviolet rays (wavelength 340 nm, black panel temperature 65 ° C., Temperature in the tank 25 ° C., relative humidity 50%, illuminance 0.50 W / m ² ). The strip obtained in Example 2 had a black color at 25 ° C. before the test, but when irradiated with ultraviolet rays for 6 hours, the temperature-responsive coating layer was changed to gray. It turned completely white upon irradiation and did not return to black when the irradiation was stopped. In contrast, the strip obtained in Example 4 had a black color at 25 ° C. before the test, but its hue (black color) did not change even after 6 hours of ultraviolet irradiation, and its function. Was not even lost. After 17 hours of irradiation, the hue of the temperature-responsive coating layer changed to gray, and it took 35 hours of ultraviolet irradiation until it completely turned white and did not return to black. This confirmed that the strip of Example 4 had improved resistance to ultraviolet light.

[Example 5]
A gravure ink (trade name “Chromi Color Black to Pink“ Temperature Type 27 ””, manufactured by Matsui Dye Chemical Co., Ltd.) is applied to one side of the base paper obtained in Example 1 with a gravure coater at 8 g / m ^2. Worked. Furthermore, temperature gravure ink (trade name “Chrome Color Black to White“ Temperature Type 27 ”) is applied on the opposite side of the base paper with a gravure coater at 8 g / m ² to form a temperature-responsive coating layer on the front and back sides. was. further, polyvinyl alcohol (Kuraray Poval 117, manufactured by Kuraray Co., Ltd.) on both sides of a base paper of a 5 mass% aqueous solution of was 3 g / ^{m 2} coated with an air knife coater. This punching machine with a 5 mm × 6 mm A thin piece was obtained by punching into a rectangular shape, and the resulting thin piece was black in temperature-responsive coating layer at 25 ° C, but when heated to 30 ° C, the front and back sides were pink and white, respectively. Was presented.

[Example 6]
A transparent multilayer film (trade name “MLF16.5”) having a thickness of 16 μm is prepared as a base material, and a temperature gravure ink (trade name “chromi color black to blue“ temperature type 27 ””, Matsui Dye Co., Ltd. A stripe pattern was printed at intervals of 3 mm using a chemical industry) (locations where printing was performed on the substrate and non-printing locations were alternately arranged at intervals of 3 mm in a stripe shape). Further, a temperature gravure ink (trade name “Chrome Color Black to White“ Temperature Type 27 ”) was applied to the entire surface so as to cover the stripe pattern, thereby forming a temperature-responsive coating layer. On the surface, a 5% by weight aqueous solution of polyvinyl alcohol (Kuraray Poval 117, manufactured by Kuraray Co., Ltd.) was coated with an air knife coater at 4 g / m ² . The work layer was black and the stripe pattern could not be seen, and when viewed from the film side, the color shift effect changed from green to red depending on the angle was conspicuous. A blue and white stripe pattern emerged, as seen from the film surface, the white part is the original pink color of the film and the blue part is the film. Looked violet mate with pink. Thereby, the temperature was confirmed that the pattern emerges film is obtained in that change. This was punched into a rectangle of 5 mm × 6 mm in the punching machine to obtain a strip.

[Example 7]
A transparent multilayer film (trade name “MLF16.5”) having a thickness of 16 μm is prepared as a base material, and a temperature gravure ink (trade name “Chrome Color Newborn to White“ Temperature Type 27 ””, Matsui Co., Ltd. is provided on one side. A stripe pattern was printed at intervals of 3 mm using a dye chemical industry) (a portion where printing was performed on a substrate and a non-printing portion were alternately arranged at intervals of 3 mm in a stripe shape). Furthermore, temperature gravure ink (trade name “Chrome Color Fast Blue to White“ Temperature Type 27 ”, manufactured by Matsui Dye Chemical Co., Ltd.) is applied over the entire surface to cover this stripe pattern, and temperature responsive coating is applied. A construction layer was formed. The other side of the base paper was coated with 4 g / m ² of 5% by weight aqueous solution of polyvinyl alcohol (Kuraray Poval 117, manufactured by Kuraray Co., Ltd.) using an air knife coater. The resulting film showed white and blue stripe patterns at 25 ° C. When viewed from the film surface, a portion where a color shift effect changing from green to red is seen and a portion where a color shift effect changing from blue to purple is seen formed a stripe pattern. When this was placed at 30 ° C., any temperature-responsive coating layer turned white, and the original pink color of the film could be seen. This was punched into a 5 mm × 6 mm rectangle with a punching machine to obtain strips.

[Example 8]
<Preparation of paper stock>
NBKP 20 parts by mass and LBKP 80 parts by mass were 350 ml C.I. S. F. And 10 parts by weight of white clay, 0.4 parts by weight of paper strength enhancer (trade name “Polystron 117”, manufactured by Arakawa Chemical Co., Ltd.), sizing agent (trade name “Size Pine E50”, Arakawa) (Chemical Industry Co., Ltd.) 1.0 part by mass, and further 2.0 parts by mass of a sulfuric acid band were added to prepare a stock.
<Paper making>
When making a base paper having a basis weight of 110 g / cm ² using a long net paper machine, each strip of the example is used as a paper base before forming a paper layer on the paper net using an apparatus described in JP-A-7-145600. And sprinkled evenly. The apparatus was adjusted so that the distribution density of the strips was 30 to 40 per 10 × 10 cm ² of paper. Thereafter, drying was performed according to a conventional method to obtain a paper.

When the strips obtained in Examples 1 to 7 were formed on paper by the method of Example 8, the following effects were produced.
(1) When the paper on which the strip obtained in Example 1 was engraved was confirmed, about half of the strip was engraved on the side on which the temperature-responsive coating layer side was visible. The temperature-responsive coating layer side of the strip exhibited a black color at room temperature set to 25 ° C., as before being woven into paper, and turned white when the temperature was raised to 30 ° C. And when it returned to 30 degreeC conditions from 30 degreeC, it returned to the original black.
(2) When the paper on which the strip obtained in Example 2 was engraved was confirmed, about half of the strip was engraved on the side where the temperature-responsive coating layer side was visible. At 25 ° C., the temperature-responsive coating layer side of the strip was black, and the strip with the opposite side (film surface side) visually recognizable had a color shift effect from green to red depending on the angle. Next, when the temperature was raised to 30 ° C., the temperature-responsive coating layer side of the strip became white and the opposite side looked pink. And when it returned to 30 degreeC conditions from 30 degreeC, each strip returned to the original color. In addition, when the obtained paper was made into A4 size and subjected to a commercially available color copier (trade name “PIXEL CLC1160”, manufactured by Canon Inc.), the color and glitter of the strips were not reproduced, preventing forgery. The effect was confirmed.
(3) When the paper on which the strip obtained in Example 3 was formed was confirmed, about half of the strip was formed on the side where the temperature-responsive coating layer was visible on the paper surface side. At 25 ° C., the temperature-responsive coating layer side of the strip was black, and the strip that was visible on the opposite side showed a blue pearly luster. When the temperature was raised to 30 ° C., the black strip turned white, and the strip on the opposite side was white at first glance, but depending on the angle, the effect of color shifting to blue or yellow was seen. And when it returned to 30 degreeC from 30 degreeC, each strip returned to the original color.
(4) When the paper on which the strip obtained in Example 4 was made was confirmed, the same hue change effect as in (2) was obtained. In addition, when the strip obtained in Example 2 was applied to the paper after being irradiated with the aforementioned ultraviolet rays for 17 hours, no change in hue was observed due to a temperature increase from 25 ° C. to 30 ° C. Even if the strips obtained in Example 4 were subjected to the same ultraviolet irradiation and then papered, the change in hue was confirmed by raising the temperature from 25 ° C to 30 ° C.
(5) The paper on which the strips obtained in Example 5 were made was all black at 25 ° C., but when heated to 30 ° C., pink and white strips were mixed. Looked. This is because different temperature-responsive coating layers were provided on both sides of the strip. Specifically, about half of each temperature-responsive coating layer that had been engraved on the visible side of the paper surface, one layer turned pink, and the other layer turned white It is. And when it returned to 30 degreeC from 30 degreeC, each strip returned to original black.
(6) When the paper on which the strip obtained in Example 6 was engraved was confirmed, about half of the strip was engraved on the side on which the temperature-responsive coating layer side was visible. At 25 ° C., the temperature-responsive coating layer side of the strip was black, and the strip that was visible on the opposite side showed a color shift effect from green to red depending on the angle. Next, when the temperature was raised to 30 ° C., the temperature-responsive coating layer side of the strips changed into two colors of blue and white, and the opposite side looked pink and purple. And when it returned to 30 degreeC from 30 degreeC, each strip returned to the original color.
(7) When the paper on which the strip obtained in Example 7 was made was confirmed, about half of the strip was made on the side where the temperature-responsive coating layer was visible on the paper surface side. At 25 ° C, the temperature-responsive coating layer side of the strip shows two colors, white and blue, and the strip that can be seen on the opposite side has a color shift effect from green to red and a color shift effect from blue to purple. It was seen. Next, when the temperature was raised to 30 ° C., the temperature-responsive coating layer side of the strips became all white, and the opposite side looked the original pink color of the film. And when it returned to 30 degreeC from 30 degreeC, each strip returned to the original color.

As described above, since the hue of the strip present in the anti-counterfeit paper of the present invention changes in hue due to a temperature change, it is very easy to determine forgery. In particular, forgery can be determined without using a special instrument by designing the strip so that the hue changes depending on the body temperature of the hand. Furthermore, by using other anti-counterfeit technology together with the anti-counterfeit paper of the present invention, a higher anti-counterfeit effect can be obtained. For example, techniques such as blending of special fibers such as dyed fibers and magnetic fibers, blending of fluorescent coloring particles, threading, and papering may be used in combination. Furthermore, post-processing techniques such as embossing and printing may be used in combination.

The anti-counterfeit paper using the strips of the present invention utilizes the feature that it is possible to easily determine forgery, various tickets, banknotes, checks, stock certificates, bonds, gift certificates, cards, confidential documents, passports, identification cards For example, it can be suitably used for applications requiring anti-counterfeiting effects.

Claims (14)

A strip provided with a temperature-responsive coating layer on which at least one surface of a base material changes its hue when the temperature changes. The strip according to claim 1, wherein the hue of the temperature-responsive coating layer reversibly changes as the temperature changes. The strip according to claim 1 or 2, wherein the substrate is paper. The strip according to claim 1 or 2, wherein the substrate is a transparent multilayer film. The strip according to any one of claims 1 to 4, wherein a nacreous layer is provided on the substrate. The strip according to any one of claims 1 to 5, wherein an ultraviolet absorbing layer is provided on the substrate. The strip according to any one of claims 1 to 6, wherein the temperature at which the hue changes is in the range of -4 ° C to 58 ° C. The strip according to any one of claims 1 to 6, wherein the temperature at which the hue changes is in the range of 25C to 33C. Two or more types of temperature-responsive coating layers that exhibit the same hue at room temperature but differ in hue at any temperature other than room temperature are present on one side of the substrate, or on both sides of the substrate. The strip according to any one of claims 1 to 8, characterized in that. Two or more types of temperature-responsive coating layers that have different hues at room temperature but have the same hue at any temperature other than room temperature are present on one side of the substrate, or separated on both sides of the substrate The strip according to any one of claims 1 to 8, which is present. An anti-counterfeit paper characterized in that the strip according to any one of claims 1 to 10 is used. The anti-counterfeit paper according to claim 11, wherein two or more kinds of strips exhibiting different hue changes are used. The anti-counterfeit paper according to claim 12, wherein two or more kinds of strips exhibit the same hue at room temperature but have different hues at any temperature other than room temperature. The anti-counterfeit paper according to claim 12, wherein two or more kinds of strips exhibit different hues at room temperature but have the same hue at any temperature other than room temperature.