JP2893310B2 - Anti-counterfeit paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to anti-counterfeit paper. More specifically, the present invention relates to a forgery prevention sheet that can obtain only a copy having a color tone completely different from that of an original even when a copy is performed by a copying machine.

[0002]

2. Description of the Related Art The accuracy of recent copying machines has been remarkably improved, and in particular, the spread of electrophotographic color copying machines has facilitated forgery of various securities. To prevent this, various anti-counterfeiting means have been considered, but one of them is to utilize the fact that current copiers cannot reproduce brilliant ones, for example, metallic colors or interference colors. There is something.

For example, as proposed in Japanese Utility Model Application Laid-Open No. 58-168754, a luminous plate such as an aluminum foil having a remarkable metallic color is provided on the upper surface of a base paper, and a character pattern is formed on the luminous plate surface. There is a proposal for paper that cannot be copied by the machine.
When this is copied, the character pattern applied to the paper surface becomes unreadable because the foil surface is darkened and copied when light is irradiated from the copying machine. This sheet has the advantage that copying itself cannot be performed (the copy cannot be read), but has the disadvantage that the metallic color is emphasized too much because the area of the glittering plate occupying the sheet is so uncomfortable. In addition, there are other problems, such as a complicated paper manufacturing process, which inevitably increases the cost, and difficulty in recovering papermaking fibers from waste paper.

[0004] The present inventors have conducted studies for the purpose of solving these problems. The inventors of the present invention have changed their ideas and have noticed that even if they are copied by a color copying machine, if they are copied in a hue different from that of the original document, it can be determined whether they are genuine.

The present inventors first sliced a silver-aluminized polyester film excellent in brilliancy,
We considered making it into paper. Since the paper produced in this way cannot reproduce the metallic glossiness with a color copying machine, the portion where the strips are mixed is simply copied in black, which proves that the paper has anti-counterfeiting ability. However, it was found that in the paper manufactured in this manner, the strip did not adhere firmly to the paper, and the strip was dropped during printing, causing a serious problem. Further, this paper has another problem that it is difficult to remove the polyester film constituting the strip, and it is extremely difficult to recover the papermaking fibers from waste paper or waste paper.

[0006]

DISCLOSURE OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and as a result of diligent studies, it has been found in Japanese Patent Application No. Hei.
An application for anti-counterfeit paper was made as 114,099. The gist of the application is that in a forgery prevention paper in which glittering strips are ubiquitously provided on the surface of a base paper, the strips have a performance capable of adhering to the base paper in a paper making process. Anti-counterfeit paper. This anti-counterfeit paper has fine strips uniformly distributed on the surface of the base paper and has an excellent anti-counterfeiting effect. In some cases, it is preferable to be unevenly distributed in a limited width. The present invention has been made to solve this problem.

[0007]

The present invention will be described with reference to the drawings. FIG. 1 is a top view of an example of the forgery prevention paper of the present invention, and FIG. 2 is a partially enlarged cross-sectional view taken along line AA ′ of FIG. The gist of the present invention is to provide a forgery prevention paper in which glittering strips 2 are unevenly distributed on the surface of the base paper 1 in a streak-like manner. It is a forgery prevention paper characterized by having.

In order that the strip 2 can be adhered to the base paper in the paper making process, it is preferable to use a film having a hot water dissolving temperature of 60 to 80 ° C. as one of the constituent elements of the strip. By doing so, the film swells due to the heat generated when the wet paper is dried in the drying step during papermaking, and adheres firmly to the paper.

The hot water-soluble film to be used is such that the film is not dissolved or excessively swelled by water at the time of forming a paper web (wet part), and a wet paper drying zone (a multi-cylinder cylinder dryer) during a paper making process. Or a Yankee dryer), it is necessary that the film does not undergo deformation that causes a practical problem, and that the film has excellent adhesion to the base paper after drying, and it has also been found that the film has this performance.

Another advantage of using this film is that it is easy to treat waste paper or waste paper that always occurs in the paper printing process or the like during paper production. This is because the film constituting the strip can be easily dissolved by heating the service water with a beater, a pulper, or the like, and treating the waste paper or waste paper.

There are various water-soluble films, for example, starch-based, methylcellulose-based, carboxylated methylcellulose-based, hydroxyethylcellulose-based, polyvinyl alcohol (hereinafter referred to as PVA) -based, polyvinylpyrrolidone-based, vinylethylether-maleic anhydride copolymer. Film, polyacrylic acid film, polyethylene oxide film and the like. It is necessary that the film used in the present invention be dissolved in hot water at 60 to 80 ° C., and the above-mentioned water-soluble polymers included in this range, a functional group is introduced into these, and a water-proofing agent is used. Those having an increased dissolution temperature in combination can be used.

In the present invention, it is preferable to use PVA because it is relatively inexpensive, easily available, and has appropriate physical strength. The solubility of PVA in water is largely controlled by the degree of polymerization and the degree of saponification, particularly the degree of saponification. For example, water having a saponification degree of 88% or less completely dissolves in water at 20 ° C., but about 50% at a saponification degree of 97%.
It can be dissolved at about 80 ° C for the first time in complete saponification with hot water at ℃. In the case of a film that dissolves at a temperature lower than 60 ° C., when the film is flaked and incorporated, the flakes dissolve or excessively swell in a drying zone of a paper machine, and cannot maintain a predetermined shape. For those that dissolve, 8
Since it is extremely difficult and dangerous to reach a temperature of 0 ° C. or higher, the dissolution temperature must be in the above range.
The thickness of the hot water-soluble film is usually 5 to 100 µm, preferably 10 to 25 µm.

Next, an example of manufacturing a strip will be described. Example 1 A metal-deposited layer of aluminum, tin, zinc, chromium, cobalt, nickel, copper, gold, silver, or the like is formed on one or both sides of the above-mentioned hot water-soluble film by vacuum evaporation, sputtering, or ion plating. And the like. The deposition thickness is typically in the range of 200 to 1500 Angstroms. In the present invention, it is preferable to use aluminum as the metal in the present invention because it is inexpensive, hardly corrodes, has excellent metallic luster, and easily dissolves in alkali.

Next, a coating layer made of a resin or a resin and a colorant is formed on the surface to be deposited. It is desirable to use an organic solvent-based resin because it prevents deformation of the hot water-soluble film and does not impair coatability, and a resin that is soluble in a hot alkaline aqueous solution is used in consideration of wastepaper recovery efficiency. It is particularly preferred to do so. Examples of resins that are soluble in hot alkaline aqueous solutions include vinyl acetate resins, polyester resins, acrylic resins, polycarbonate resins, polyacetal resins, ionomer resins, nitrocellulose resins, acetylcellulose resins, and maleic acid resins. Phenol-based resin, melamine-based resin, urea-based resin, casein-based resin, shellac-based resin, etc., or a resin modified by introducing a functional group such as a hydroxyl group or a carboxyl group so that these become alkali-soluble. Alternatively, a mixture thereof may be used. In the present invention, 60 to 80 of these resins are used.
It is preferable to select and use one that does not dissolve in hot water but dissolves in hot alkaline water for the first time in the temperature range of ° C. The alkali concentration at the time of pulp recovery treatment from broke is usually 0.01
Since it is in the range of 0.5% by weight, it is preferable to use a resin that dissolves in this range.

As the coloring agent, organic pigments, inorganic pigments, dyes and the like can be used. In the case of performing color coating on the vapor deposition layer, it is preferable to use a dye in order not to lower the metallic luster.
When no coloring agent is used, a deposited metal color, for example, aluminum can be used to obtain a silver color, and a yellow color can be used to obtain a gold color. In addition, auxiliary agents such as a viscosity adjusting agent and a curing agent may be used in combination as long as the object of the present invention is not impaired. In some cases, an anchor coating layer and a back coating layer are provided. The resin used for the anchor coating layer and the back coating layer are preferably dissolved in a hot alkaline aqueous solution at 60 to 80 ° C., and a coloring agent and other additives can be used in combination. The paint prepared in this way is applied to the deposition surface or the film surface.
To 10 μm, preferably 2 to 5 μm. The sheet produced in this way is shredded in the manner described below.

Example 2 Use of Transfer Foil Transfer foils having an interference color and transfer foils having a metallic color are known as transfer foils having a glittering property. For example, a transfer foil having an interference color is formed by sequentially forming a resin layer (a coating layer mainly serving as a release layer and a surface protection layer, for example, a nitrocellulose base material) and a very thin aluminum vapor-deposited layer (light It is composed of a semi-transmissive layer), a very thin resin coating layer (interference layer), an aluminum deposition layer (light reflection layer), and a heat-sensitive adhesive layer. As another example, an interference layer formed by depositing an inorganic oxide such as SiO ₂ instead of the above-described resin interference layer is also known. As another example, a transfer foil utilizing a hologram interference color is known. this is,
A resin layer (for example, a coating layer mainly composed of nitrocellulose, which also functions as a release layer and a surface protection layer) is formed on the polyester base film, and a hologram pattern is heat-embossed on the surface thereof. And a layer having a heat-sensitive adhesive layer formed thereon.
Using these transfer foils, the heat-sensitive adhesive is combined with a substrate surface, for example, a hot water-soluble film surface, passed between hot rolls, bonded together, cooled, peeled off the polyester base film, and cut into pieces. Further, a hot water-soluble film may be further attached to the transfer surface using, for example, a polyurethane-based adhesive or the like to form a small piece. This configuration has the advantage that the hot water-soluble film surface is located on the outside of both surfaces, so that the adhesion to the paper becomes stronger.

The metal transfer foil may be formed, for example, by coating a resin layer (for example, nitrocellulose serving as a release layer and a surface protection layer, for example, with nitrocellulose as a main component and, if necessary, a colorant) on a polyester base film. Layer), an aluminum vapor-deposited layer, and a heat-sensitive adhesive layer. Using this transfer foil,
The heat-sensitive adhesive is combined with a substrate surface, for example, a hot water-soluble film surface, passed between hot rolls, bonded together, cooled, peeled off the polyester base film, and cut into pieces. Further, a hot water-soluble film may be further attached to the transfer surface using, for example, a polyurethane-based adhesive or the like to form a small piece. This configuration has the advantage that the hot water-soluble film surface is located on the outside of both surfaces, so that the adhesion to the paper becomes stronger.

Example 3 A method in which a coating liquid obtained by mixing a hot water-soluble binder with a metal powder or a pearl pigment is applied to paper to form a small piece. 80 to 300 parts by weight of a hot water-soluble binder such as polyvinyl alcohol is usually added to 100 parts by weight of a metal powder such as aluminum or brass, or 100 parts by weight of a pearl pigment such as mica or bismuth oxychloride coated with titanium oxide. It is prepared and usually coated on a base paper having a basis weight of 30 to 100 g / m ² , and then sliced. When a pearl pigment that emits iris is used as a pearl pigment, the presence of the pearl pigment can be confirmed when viewed with the eyes, but it is possible to obtain an effect that the iris color cannot be reproduced with a color copier. . There are various iris colors,
Two or more strips emitting different iris colors can be used in combination.

Example 4 A method in which a coating liquid in which a binder is mixed with metal powder or pearl pigment is applied to paper, and a hot water-soluble binder such as PVA is coated on the surface of the paper to form a small piece. The strip of this configuration has the advantage that the adhesion to the base paper is more improved than the strip of Example 3.

Example 5 A method of laminating hot water-soluble films on both surfaces of a glittering film to form pieces. Examples of the film having glitter include a polyester film formed by depositing a metal, a polyester film having a resin layer formed thereon, a hologram pattern embossed on the surface thereof, and a metal deposited, and a hologram pattern directly embossed on a vinyl chloride film. Metal thin film, polyester film thin metal film (semi-transmissive layer), then interference layer,
Any of a metal vapor-deposited layer (light reflecting layer) formed, a metal powder coated on a base sheet with an adhesive, and a pearl pigment coated on a base sheet with an adhesive can be used. A hot water-soluble film is adhered to both sides of the glittering film using a polyurethane-based dry laminating adhesive or the like, and cut into pieces.

Example 6 A method in which a metal powder or a pearl pigment is kneaded into a hot-water-soluble resin and formed into a film to be fragmented. When a leaf-shaped metal powder or a pearl pigment is kneaded, the brilliancy is improved by stretching the film uniaxially or biaxially.

In the present invention, any shape such as a circle, an ellipse, a square, a rectangle and a star can be selected as the shape of the strip. Any method can be adopted as the method, such as a method of punching out using the tooth profile of the above-mentioned shape, or a method of slitting with a microslitter and cutting it into small pieces. The size of fragmentation is usually about 0.2 to 10 mm.

The paper of the present invention includes bleached softwood kraft pulp (NBKP), bleached hardwood kraft pulp (LBKP),
Mainly papermaking pulp such as softwood bleached sulphite pulp (NBSP) and thermomechanical pulp (TMP), with dry paper strength agent, wet paper strength agent, sizing agent, fixing agent, retention improver, and improved drainage Agents, defoamers, dyes, coloring pigments, fluorescent agents, etc., as appropriate, and usually has a freeness of 550.
~ 250 ml C.I. S. F. Using a well-known paper machine such as a fourdrinier paper machine or a round paper machine. In the present invention, it is also possible to apply starch, polyvinyl alcohol, various surface sizes, etc. to the paper surface during the paper making process using a size press device or the like. Further, if necessary, a machine calendering treatment or a super calendering treatment is performed to appropriately improve the surface smoothness.

The strips are formed so as to be unevenly distributed near the surface of the base paper when the base paper is formed, and the following method can be employed. 1) Sprinkle the strip into a strip on a fourdrinier or a round paper machine. 2) At a position immediately before or immediately after the slicing of the fourdrinier paper machine, a strip of paper material or water is blown out from several places in the width direction by a nozzle in a streak shape. 3) Sprinkle fine strips on the wet paper just before the press roll. By doing so, the strips are unevenly distributed near the surface of the base paper. That is, the strips are exposed on the surface of the base paper, and the other part penetrates near the surface, so that the strips are unevenly distributed near the surface.

The paper web thus formed is heated and dried in a drying zone of a paper machine such as a cylinder drier or a Yankee drier. In the initial stage of drying, since the paper web contains a large amount of water, hot water also comes into contact with the small pieces, and the hot water-soluble film or the like swells or a very small portion thereof dissolves and strongly adheres to the paper. In order to impart surface smoothness to the paper, machine calendering or super calendering can be appropriately performed. As described above, the forgery prevention paper of the present invention is manufactured.

As the strips, several kinds of strips having the same hue or different hue may be used in combination, or strips having the same hue but different tones may be incorporated.

The anti-counterfeit paper of the present invention can be used in combination with other anti-counterfeit means. For example, clarification, blending with dyed fibers, threading, etc. Thereby, the forgery prevention effect can be further enhanced.

[0028]

EXAMPLE 1 Metal aluminum was vacuum-deposited on a PVA film having a thickness of 25 μm and having a hot water dissolution temperature of 80 ° C. in a vacuum of 500 Å, and a yellow dye (trade name: Oleosol First Yellow, manufactured by Sumitomo Chemical Co., Ltd.) was deposited on the deposition surface. A coating obtained by adding 15 parts by weight to 100 parts by weight of the alkali-soluble nitrocellulose resin was applied to a thickness of 3 μm (dry thickness). Then, a circular strip having a diameter of 1 mm was produced using a punching machine.
350 ml of 20 parts by weight of NBKP and 80 parts by weight of LBKP
C. S. F. 10 parts by weight of clay, 0.3 parts by weight of a paper strength agent (trade name "Polystron 191", manufactured by Arakawa Chemical Industry Co., Ltd.), a sizing agent (trade name "Size Pine E", Arakawa 1.0 part by weight (manufactured by Chemical Industry Co., Ltd.) and an appropriate amount of a sulfuric acid band were added to prepare a stock. Using a fourdrinier paper machine, a paper having a basis weight of 110 g / m ² and a papermaking width of 1120 mm was used to suspend the strips having the above constitution in water during papermaking, guided by a metal tube and sprinkled in a streak shape immediately after slicing. Six metal tubes were installed in the width direction at the same interval every 177 mm, and the same strip suspension was supplied to each metal tube. Thereafter, it was manufactured according to a conventional method (drying was performed with a multi-cylinder cylinder dryer). The obtained anti-counterfeit paper had strips unevenly distributed in the flow direction every 177 mm in the width direction. After performing predetermined printing using this paper and copying it with a color copier (trade name “Cannon Pixel”), the metal color (in this case, gold or silver) of the strip is not reproduced, and it is determined by visual inspection. The difference between the two (the manuscript and the copy) was clearly recognized. Stripping did not occur even after the offset printing. 5 parts by weight of the paper thus prepared, 95 parts by weight of water (that is, pulp concentration of 5%) and 0.1 part by weight of caustic soda were charged into a high-concentration pulper and rotated while blowing live steam to raise the temperature to 60 ° C. As a result, the base film, the vapor-deposited layer, and the resin-coated layer constituting the strip were completely dissolved.
The remaining dye was refined and completely dispersed in the pulp, and no effect was observed even when paper was made using the recovered pulp.

Example 2 A coated paper having a basis weight of 70 g / m ² was coated on both sides with a particle size of 40 μm.
Using a paint composed of 100 parts by weight of pearl pigment of mica powder having a titanium oxide coverage of 28% and 200 parts by weight of polyvinyl alcohol, using an air knife coater, one side of 7 g / m2.
Coated ^two by ^two . Then 1mm using a punching machine
X1.5 mm rectangular strips were produced. Except for changing the configuration of the strip to the above, the same forgery prevention paper as that of Example 1 was manufactured. The obtained paper is different from the strip of Example 1 and cannot be immediately recognized as being mixed. By tilting the paper at an appropriate angle, the irradiation light incident on the strip is reflected and enters the eye for the first time. The existence was confirmed. The paper had very little discomfort due to the inclusion of small pieces. Stripping did not occur even after the offset printing. When this paper was copied with a color copier (trade name "Cannon Pixel"), the color of the strip (in this case, the pearl luster color) was not reproduced, and the difference between the two (the original and the copy) was clear by visual inspection. Was recognized. The paper was treated in the same manner as in Example 1, but the papermaking pulp could be easily collected.

[0030]

As described above, the anti-counterfeit paper of the present invention is manufactured and has remarkable effects as described below. 1) Even if copying is attempted by a color copying machine, the color of the glittering strip mixed in the paper cannot be reproduced, so that it is possible to immediately determine whether or not it is a forgery. In particular, strips using pearl pigments have the advantage that they do not cause discomfort due to being mixed. 2) Since the strips are unevenly distributed on the surface of the paper or near the surface of the paper, they can be suitably used for design applications in which this portion is not printed. 3) Since the strips are firmly adhered to the paper, there is no problem that the strips fall off during printing. 4) It is possible to manufacture strips that can easily recover papermaking fibers from waste paper and waste paper. 5) Taking advantage of such characteristics, the anti-counterfeit paper of the present invention is suitably used for check paper, stock paper, bond paper, bill paper, gift certificate paper, passport paper, various ticket papers, boarding tickets, and the like.

[Brief description of the drawings]

FIG. 1 is a top view of an example of a forgery prevention sheet of the present invention.

FIG. 2 is a partially enlarged cross-sectional view taken along line A-A 'of FIG.

[Explanation of symbols]

 1 base paper 2 luminous strips

Claims (12)

(57) [Claims] An anti-counterfeiting paper in which glittering strips are unevenly distributed in the flow direction of the base paper on the surface of the base paper, the strips can adhere to the base paper in a paper making process. Anti-counterfeit paper characterized by its performance. 2. The anti-counterfeit paper according to claim 1, wherein one of the constituent elements of the strip is a film having a hot water dissolving temperature of 60 to 80 ° C. 3. A strip comprising a film having a hot water dissolving temperature of 60 to 80 ° C., a metal deposition layer formed on one or both sides of the film, and a coating layer comprising a resin or a resin and a colorant formed thereon. The anti-counterfeit paper according to claim 1, wherein the anti-counterfeit paper comprises: 4. The forgery prevention paper according to claim 3, wherein the resin is soluble in alkaline hot water at 60 to 80 ° C. 5. The strip has a metal vapor-deposited layer formed on one side of a film having a hot water dissolution temperature of 60 to 80 ° C., and a coating layer comprising a resin and a colorant is formed on the metal vapor-deposited layer as required. 2. The forgery-prevention paper according to claim 1, further comprising a film having a hot water dissolving temperature of 60 to 80 [deg.] C. bonded to the surface thereof. 6. The forgery prevention according to claim 1, wherein the strip is formed by transferring a transfer foil having an iris color or a metallic luster to a film having a hot water dissolving temperature of 60 to 80 ° C. Paper. 7. A transfer foil having an iris or metallic luster is transferred to a film having a hot water dissolving temperature of 60 to 80 ° C., and a film having a hot water dissolving temperature of 60 to 80 ° C. is applied to the surface thereof. The forgery-prevention paper according to claim 1, wherein the paper is bonded. 8. The strip is obtained by coating a paper with a coating liquid obtained by mixing a binder with a metal powder or a pearl pigment, and then laminating a hot water-soluble film on both sides. The forgery prevention paper according to 1. 9. The anti-counterfeit paper according to claim 1, wherein the strip is made of a film having a hot water dissolving temperature of 60 to 80 ° C. into which metal powder is kneaded. 10. The anti-counterfeit paper according to claim 1, wherein the strip is made of a film having a hot water dissolving temperature of 60 to 80 ° C. into which a pearl pigment is kneaded. 11. The anti-counterfeit paper according to claim 1, wherein the strips are formed by coating a paper with a coating liquid obtained by mixing a hot water-soluble binder with a metal powder or a pearl pigment. 12. The forgery prevention paper according to claim 8, wherein the pearl pigment is a pearl pigment emitting iris color.