JP4390914B2 - Anti-counterfeit thread and anti-counterfeit paper using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an anti-counterfeit thread and an anti-counterfeit paper using the same. More specifically, the present invention relates to a forgery prevention thread characterized by including a ferromagnetic material thin film layer having a large squareness ratio on the surface of a base resin film, and patterning as necessary, and a forgery prevention paper using the same.
Such anti-counterfeit paper can be used for various security media such as gift certificates, gift certificates, certificates, tickets, voting tickets, tickets, and labels.
[0002]
[Prior art]
As a measure for preventing counterfeiting of various security media, there is a method of embedding various threads on paper. Such anti-counterfeiting means using threads is provided at the stage of paper manufacture, so it is difficult to forge by methods such as color copying, scanner capture, and plate-making printing. However, there are cases where counterfeit paper incorporating a counterfeit thread imitating a genuine thread is available, and a simple magnetic thread or glitter thread alone may not be sufficient for authenticity determination.
[0003]
On the other hand, a structure in which a general magnetic recording material is combined with a thread is not an advanced anti-counterfeiting structure because it is easy to falsify magnetic recording information.
For this reason, as a data recording carrier having a higher level of anti-counterfeit structure, as a structure in which a roughened portion and a magnetic film are combined, in Japanese Patent Laid-Open No. 10-64051, a magnetically patterned magnetic plate or the like is proposed.
Therefore, the present invention intends to further improve the anti-counterfeit effect by further improving the magnetic plate and applying it to the anti-counterfeit thread and the anti-counterfeit paper using the same.
[0004]
[Means for Solving the Problems]
The first of the gist of the present invention for solving the above-mentioned problems is a thread for embedding on a forgery-preventing paper for use, and the surface of the substrate made of a resin film has a thickness of 0.01 to 0.1 μm. the smooth surface layer consisting of the film thickness of the metal is provided, the squareness ratio on the surface smoothing layer forms a ferromagnetic material thin film layer is 0.7 to 1.0 in thickness 50 nm~500 nm, the ferromagnetic material The anti-counterfeiting thread is characterized in that the thin film layer is patterned by being partially removed by thin film removing means such as a laser processing method, an etching method, or a lift-off method . Because of such a forgery prevention thread, forgery and tampering are difficult.
[0005]
Such anti-counterfeit thread, a ferromagnetic material film layer, coercivity is 0.5 to 50 Oe, and the squareness ratio can be adjusted to 0.7 to 1.0, it was or The barcode mark can be provided in a pattern. By doing so, the characteristics of the ferromagnetic material become remarkable, and forgery and alteration become more difficult.
[0006]
A second aspect of the present invention for solving the above-described problems resides in an anti-counterfeit paper characterized in that the anti-counterfeit thread is formed on a base paper. Because of such anti-counterfeit paper, it is difficult to forge and tamper.
Such a forgery-preventing paper base paper can be provided with an exposed portion that intermittently exposes the thread and a covering portion that is intermittently covered between the exposed portion and the thread. A plurality of covering portions are provided, and a plurality of anti-counterfeit threads can be incorporated. By doing so, counterfeiting and tampering become more difficult.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
The anti-counterfeit thread of the present invention is provided with a surface smoothing layer made of a metal such as aluminum, copper, tin, zinc, antimony, lead, etc. on a base made of a resin film, and smoothes fine irregularities on the surface of the resin film, The present invention relates to a forgery prevention thread in which a ferromagnetic material thin film is formed on the surface of the substrate by a vapor phase method such as sputtering, and a forgery prevention paper using them.
[0008]
The ferromagnetic material thin film used in the present invention is formed on the surface of a substrate made of a resin film by vapor phase growth such as sputtering or vapor deposition.
Although this resin film looks flat at first glance, microscopic unevenness having an average pitch and depth of about 0.01 to 0.1 μm exists when viewed microscopically. For this reason, it is difficult to stably produce a ferromagnetic thin film having hysteresis characteristics with a large squareness ratio. These fine irregularities cannot be removed only by adjusting the material composition, and in general, some kind of post-treatment is necessary to obtain good magnetic properties.
In the present invention, in order to form a ferromagnetic material thin film layer having a large squareness ratio on a substrate surface made of a resin film only by vapor deposition, 0.01 to 0 on the resin film substrate surface. A smooth surface layer made of a metal having a thickness of 1 μm is formed, and then a ferromagnetic material thin film layer is formed.
Thereby, a ferromagnetic material thin film having excellent characteristics such as a coercive force of 0.5 to 50 oersted and a squareness ratio of 0.7 to 1.0 as shown in the hysteresis characteristic curve of FIG. 3 was obtained.
In the present invention, a ferromagnetic material thin film having such excellent characteristics is used as a thread for preventing forgery.
[0009]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view showing an embodiment of the thread for preventing forgery of the present invention. In the case of this embodiment, the anti-counterfeit thread 10 has a surface smoothing layer 13 made of metal formed on a base material 11 made of a resin film, and a ferromagnetic material thin film layer on the surface of the smoothing layer 13. 15 is attached and provided.
FIG. 2 is a cross-sectional view showing another embodiment of the thread for preventing forgery of the present invention.
In this other embodiment, the portion having the ferromagnetic material thin film layer 15 is combined with the portion without the ferromagnetic material layer 15 by patterning as will be described later, and each of the magnetic characteristics read from the unique pattern configuration is uniquely identified. It is to give information.
[0010]
An adhesive layer 16a is provided on the surface of the substrate 11 opposite to the surface on which the ferromagnetic material thin film layer is formed (hereinafter referred to as “back surface”), and the upper surface of the ferromagnetic material thin film layer 15 (hereinafter referred to as “surface”) Can be provided with an adhesive layer 16b. These adhesive layers have the effect of increasing the adhesive strength with the paper when the thread is incorporated into the anti-counterfeit paper.
[0011]
Hereinafter, each component of the anti-counterfeit thread will be described in more detail.
As the substrate 11, a water-resistant and heat-resistant resin film can be used. Generally, a polyethylene terephthalate (PET) resin film and other polyester resin films, polyamide resin films, polyimide resin films, polycarbonate resin films are used. , Polystyrene resin film, polypropylene resin film, polysulfone resin film, polyphenylene sulfide resin film, cellulose resin film, and the like. The recommended thickness is about 1 to 300 μm, preferably 5 to 50 μm.
[0012]
Examples of the surface smoothing layer 13 include metals such as aluminum, copper, tin, zinc, antimony, and lead. These metal thin film forming means are formed on the resin film substrate 11 by vapor phase growth such as sputtering or vapor deposition. The film thickness of the smoothing layer 13 needs to be formed so as to fill the fine irregularities present on the surface of the resin film substrate 11. For example, when the substrate 11 is a PET film, the film thickness is 0.01-0. A range of about 1 μm is preferable. More preferably, it is in the range of 0.03 to 0.05 μm. If the thickness is 0.01 μm or less, a stable film may not be obtained, and the characteristics may be partially deteriorated. If the thickness is 0.1 μm or more, peeling or cracking of the smoothing layer itself may occur, and the characteristics may be decreased. Because there is.
The reason why excellent magnetic properties are produced by providing the above-described surface smoothing layer is considered to be that magnetostriction caused by fine unevenness is reduced by surface smoothing. Therefore, a nonmagnetic metal is preferable as the metal used for the surface smoothing layer.
[0013]
Next, the ferromagnetic material of the ferromagnetic material thin film layer 15 may be crystalline or amorphous, and one or more of iron (Fe), cobalt (Co), and nickel (Ni). The main component is a magnetic material composed of a combination of boron (B), carbon (C), magnesium (Mg), aluminum (Al), silicon (Si), phosphorus (P), sulfur (S), Titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), copper (Cu), zinc (Zn), yttrium (Y), zirconium (Zr), niobium (Nb), molybdenum (Mo), From palladium (Pd), silver (Ag), indium (In), tin (Sn), tantalum (Ta), tungsten (W), iridium (Ir), platinum (Pt), gold (Au), lead (Pb) Several selected And a additive genus or non-metallic elements.
[0014]
Ferromagnetic material thin film layers are formed by vacuum processes such as sputtering, vapor deposition, and ion plating using an alloy composed of iron, cobalt, nickel as the main component and a material composed of additive elements or a mixture thereof as a target material or vapor deposition source. It is formed by means using The ferromagnetic material is represented by cobalt Co-zirconium Zr system or iron Fe-silicon Si.
The thickness of the ferromagnetic material thin film layer is suitably 500 to 5000 mm. The reason why the lower limit of the layer is 500 mm or less is that the thickness of the magnetic layer is reduced, so that the saturation magnetic flux decreases as the absolute amount of the magnetic body decreases, and the magnetic signal becomes smaller. This is because the thickness of the magnetic material needs to be 500 mm or more in order to obtain a magnetic signal to be used. The reason why the upper limit is 5000 mm is to make a clear distinction from a magnetic film produced by another method (usually 1 μm or more in thickness), and it is preferable to avoid making it thicker than this. is there. Further, when the thickness is larger than this, the thread characteristics are deteriorated due to curling or the like due to the internal stress of the film, and wrinkles or cracks may occur.
In view of the productivity of the ferromagnetic thin film layer and the stability of the magnetic signal, the preferred thickness of the layer is in the range of 1500 to 3000 mm (0.15 to 0.3 μm).
[0015]
Such a ferromagnetic material thin film layer exhibits unique characteristics in Hc (coercivity) and Bm (saturation magnetic flux density), and from the magnetic characteristics, the magnetic field strength applied normally and the magnetic flux density of the magnetic material magnetized by the magnetic field. Has a non-linear BH characteristic (hysteresis curve), and can be clearly distinguished from general magnetic materials.
The ferromagnetic material thin film layer used in the present invention preferably has Hc (coercivity) of 0.5 to 50 Oe and Rsq (square ratio) of 0.7 to 1.0.
FIG. 3 shows a hysteresis curve of the ferromagnetic material thin film layer. On the substrate surface that is smooth and has no irregularities, the ferromagnetic material thin film layer 15 has a small coercive force Hc and a high angle type as shown in FIG. A BH hysteresis curve with a ratio (0.8 to 1.0) is obtained.
On the other hand, in the substrate surface having irregularities, the hysteresis characteristic of decreasing the saturation magnetic flux density Bm low squareness ratio (0.5 or less) is obtained.
The squareness ratio Rsq is
Rsq = Br (residual magnetic flux density) / Bm (saturated magnetic flux density)
It is represented by
[0016]
The surface smoothing layer 13 has the effect of providing a forgery prevention thread that is the same as a general glittering thread in appearance because its glossy color is observed from the outside as reflected light in addition to the above-described magnetic property improving effect. is there. In addition, a light-reflective nonmagnetic metal material can also be used as an upper layer of the ferromagnetic material thin film. For example, gold, silver, aluminum, chromium or the like is used. In general, aluminum is preferably employed from the viewpoint of cost and technical problems, and the thickness is formed to a thickness of about 100 to 2000 mm, preferably about 200 to 1000 mm. When the latter light reflecting layer is provided, the reflection characteristics are further improved.
[0017]
When the ferromagnetic material thin film layer 15 is patterned, it can be patterned by a process such as a wet etching method and a lift-off method in addition to a dry process of forming a pattern with a laser beam. In the case of laser processing, the surface of the ferromagnetic material thin film layer 15 can be patterned by scanning with a YAG laser (wavelength 1064 nm) beam.
In many cases, by patterning the ferromagnetic material thin film layer into a barcode shape, the thread can be formed on the base paper to make a useful anti-counterfeit paper.
[0018]
The adhesive layer 16a is for increasing the adhesive strength with the paper when the anti-counterfeit thread 10 is formed on the paper, and is composed of a water-soluble binder having a heat melting temperature of 60 to 80 ° C. An agent layer can be provided on the back surface of the substrate 11. Alternatively, the adhesive layer 16b may be provided on the upper surface (surface) of the ferromagnetic material layer. Specifically, an adhesive made of starch, casein, carboxymethyl cellulose, carboxyethyl cellulose, or the like that is water-soluble can be employed.
Alternatively, the adhesive layer may be a hot melt adhesive having a heat melting temperature of 60 to 80 ° C. The coating thickness may be within a few μm.
[0019]
Next, the forgery prevention paper of the present invention will be described.
Anti-counterfeiting paper that is threaded so as to be exposed in the window is, for example, paper of a type in which glittering threads or magnetic threads are embedded in the base paper, and the base paper is glittering threads. There are known ones that include an exposed portion (window) that intermittently exposes and a covering portion that intermittently covers the glittering thread between the exposed portions.
The anti-counterfeit paper having this configuration is provided with a small convex part having the same width as or wider than the thread on one paper net part of the multi-cylinder paper machine, and the thread is placed on the convex part. It can be manufactured by supplying a stock solution. That is, in this way, the covering portion is formed because the thread is sandwiched by the stock liquid at the position where there is no convex portion, and the exposed portion is exposed from the lower surface side of the stock liquid at the convex portion position. It is formed.
[0020]
In the threaded paper with the window as described above, the glittering thread and the like are intermittently exposed at the exposed portion, so that even when copied, the metal color is not reproduced, so that forgery can be prevented. In addition, it is not necessary to check the end face of the paper to see if it is a counterfeit product, and it is possible to prevent the glittering thread or the like from being peeled off from the base paper.
[0021]
FIG. 4 is a diagram showing an embodiment of the forgery prevention paper of the present invention. 4A is a plan view thereof, and FIG. 4B is a cross-sectional view taken along line AA in FIG. 4A.
As shown in FIG. 4, in the first embodiment of the anti-counterfeit paper 20 of the present invention, a single thread 10 is drawn into the base paper 21, and the thread 10 is intermittently inserted into the base paper 21. A plurality of exposed portions 26 that are exposed to each other and a covering portion 27 that intermittently covers the thread 10 between the exposed portions. The exposed portion 26 may be the same width as the thread, but by making the both sides of the thread 10 become the watermark portion 28 by making it wider than that, the tolerance (blurring) of the thread generated during paper making is absorbed by the watermark portion. be able to.
[0022]
However, the base paper 21 is preferably configured so that both end portions of the thread 10 are covered portions 17 with respect to any thread. This is because if the end of the thread is exposed, the thread peels off. The width of the thread to be used is not particularly limited depending on the purpose of use of the paper, but a width of about 0.2 mm to 5 mm is usually used.
[0023]
FIG. 5 is a diagram showing a second embodiment of the forgery prevention sheet of the present invention. 5A is a plan view thereof, and FIG. 5B is a cross-sectional view taken along line AA in FIG. 5A. As shown in FIG. 5, in the second embodiment of the forgery-preventing paper of the present invention, a plurality of threads 10 are formed on the base paper 21, and the base paper 21 exposes the threads 10 intermittently. A plurality of exposed portions 26 and a covering portion 27 that intermittently covers the thread 10 between the exposed portions are the same as in the first embodiment.
The second embodiment is characterized in that the exposed portion 26 and the covering portion 27 appear in the same state at the same position from the end of the sheet at the thread end with respect to a plurality of threads. That is, both the thread 10a and the thread 10b are exposed at the position x from the paper edge, and both the thread 10a and the thread 10b at the position y from the paper edge. It is a covering part.
[0024]
However, the base paper 21 is preferably configured as a covering portion 27 for both threads at both ends of the thread 10. This is because if the end of the thread is exposed, the thread peels off. The width of the thread to be used is not particularly limited depending on the purpose of use of the paper, but a width of about 0.2 mm to 5 mm is usually used. The widths of the plurality of threads do not need to be the same width, and it is also arbitrary to change the color tone, optical characteristics, color development characteristics, magnetic characteristics, and the like.
As described above, by introducing two or more threads into the security medium, the method of simply pasting a forged thread increases the forgery cost and the process becomes complicated, so that the forgery suppression effect increases. .
[0025]
FIG. 6 is a diagram showing a third embodiment of the anti-counterfeit paper according to the present invention. 6A is a plan view thereof, and FIG. 6B is a cross-sectional view taken along line AA of FIG. 6A. As shown in FIG. 6, the third embodiment of the anti-counterfeit paper according to the present invention has a configuration in which a plurality of threads 10 are formed on the base paper 21, and the base paper 21 exposes the threads 10 intermittently. A plurality of exposed portions 26 and a covering portion 27 that intermittently covers the thread 10 between the exposed portions are the same as in the first embodiment.
In the third embodiment, the exposed portion 26 and the covering portion 27 are different between at least two adjacent threads of the plurality of threads at the same position from the end of the sheet at the thread end. There are features that appear. That is, at the position x from the end of the paper, it is an exposed portion for the thread 10a and a covering portion for the thread 10b. However, the base paper 21 is preferably the same as the first embodiment in that both end portions of the thread 10 are configured as the covering portions 27, and the same applies to the following embodiments.
In this way, when the exposed portion is provided in a so-called staggered pattern, it is possible to reduce the rise of the thread portion when the sheets are stacked, facilitating printing, and preventing roll-up during handling of the take-up paper. can do.
[0026]
Next, the manufacturing state of the anti-counterfeit paper of the present invention will be described.
FIG. 7 is a diagram illustrating a state in which a forgery-preventing sheet with threads is drawn. 7A is a cross section parallel to the thread, FIG. 7B is a cross section taken along line CC in FIG. 7A and perpendicular to the thread, and FIG. 7C is a cross section taken along line DD. Is shown. As shown in the figure, this threaded anti-counterfeit paper 20 is provided with ridges 29a of the sash net portion having the same width as or wider than the thread 10 at appropriate intervals on the slat mesh portion 29 of the paper machine. It can be manufactured by supplying the stock liquid 22a in a state where the thread 10 is placed on 29a. In other words, in this way, the thread 10 is sandwiched by the paper material liquid 22a at the position between the convex portions 29a and 29a, so that the covering portion 27 is formed, and at the position of the convex portion 29a, the thread 10 is the bottom surface. Therefore, when the paper is peeled from the paper mesh of the paper machine, the thread appears on the surface and the exposed portion 26 is formed.
[0027]
When the projecting portion 29a of the perforated net portion has the same width as the thread 10 as shown in FIG. 7D, the watermark portion 28 does not enter on both sides of the thread 10. In addition, when the width is set so as to straddle the thread, a watermark portion is inserted to enhance the decorative effect, and the blurring of the thread can be absorbed as described above.
When the watermark pattern 25 is provided around the thread, a pattern-like convex portion may be formed on the perforated net portion in the same manner as the convex portion 29a.
[0028]
【Example】
Embodiments of the present invention will be described below with reference to the drawings.
(Example)
<Production of magnetic thread>
As the base film 11 of the anti-counterfeit thread, a smooth and transparent polyethylene terephthalate film (“Lumirror S-28” manufactured by Toray Industries, Inc.) [thickness: 16 μm] so that the average film thickness of aluminum is 0.03 μm. The surface smoothing layer 13 was formed by vapor deposition.
[0029]
Subsequently, a ferromagnetic material thin film layer 15 made of iron Fe-silicon Si was formed on the surface smoothing layer so as to have a film thickness of 0.2 μm by sputtering.
Mark writing with a YAG laser (wavelength 1064 nm) was performed in order to repeatedly provide a reduced barcode mark within the range of 2 mm width of the ferromagnetic material thin film layer 15. A beam having a diameter of about 50 μmφ was scanned in parallel, and the removal portion of the ferromagnetic material thin film layer 15 having a width of 50 μm was formed in stripes every 100 μm, thereby providing a clear barcode mark. The laser processing conditions are as follows.
〔Processing conditions〕
Equipment: “Laser Marker FL-50” manufactured by Fuji Electric Co., Ltd.
Irradiation energy: 5-6W (current value 8A)
Scanning speed: 100mm / sec
[0030]
After applying the vinyl chloride-based adhesive to a thickness of 1 μm on the back surface of the base material film of the processed thread, the slitter machine is used to slit it to a width of 2 mm. completed.
[0031]
As a result of measuring the magnetic characteristics of this thread, the squareness ratio was 0.9 and the coercive force was 30 oersted in the portion without patterning. Moreover, the squareness ratio of the part which does not provide the surface smoothing layer separately conducted in the comparative test was 0.5. The measurement was performed using a VSM (sample vibration magnetometer) with a DC magnetic field, but the same result was obtained with a BH analyzer using an AC magnetic field.
[0032]
<Making of anti-counterfeit paper>
As shown in FIG. 5, a papermaking net in which the exposed portion 26 is repeated at a pitch of 10 mm × width of 10 mm and the covering portion 27 at a pitch of 10 mm so that the two anti-counterfeit threads 10 manufactured above appear on the anti-counterfeit paper as shown in FIG. Using a pattern paper machine, paper was made on high-quality paper of 90 kg / sixth edition. In addition, the height of the convex part of the netting part was adjusted so that the upper part of the covering part 27 was 35 g / m ² and the lower part of the covering part was 69 g / m ² .
When the anti-counterfeit paper 20 thus completed was read with a magnetic head, the barcode could be read.
[0033]
【The invention's effect】
The anti-counterfeit thread according to the present invention forms a surface smoothing layer on a substrate made of a resin film , and the ferromagnetic thin film layer has a squareness ratio of 0.7 to 1.0 on the surface smoothing layer. Is formed with a thickness of 50 nm to 500 nm, and the ferromagnetic thin film layer is patterned by partial removal by thin film removing means such as a laser processing method, an etching method, and a lift-off method . It is possible to provide a large specific magnetic property, and has an anti-counterfeit effect that cannot be obtained with a normal magnetic thread or a glittering thread. In addition, since the anti-counterfeit paper of the present invention has such anti-counterfeit threads incorporated in the base paper, it is difficult to duplicate, and the reliability of gift certificates and other securities can be improved.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of an anti-counterfeit thread according to the present invention.
FIG. 2 is a cross-sectional view showing another embodiment of the thread for preventing forgery of the present invention.
FIG. 3 is a diagram showing a hysteresis curve of a ferromagnetic thin film layer.
FIG. 4 is a diagram illustrating a first embodiment of a forgery prevention sheet according to the invention.
FIG. 5 is a diagram showing a second embodiment of the forgery prevention sheet of the invention.
FIG. 6 is a diagram showing a third embodiment of the forgery prevention sheet of the invention.
FIG. 7 is a diagram illustrating a state in which a forgery-preventing paper with a thread is formed.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Anti-counterfeit thread 11 Base material 13 Surface smoothing layer 15 Ferromagnetic material thin film layers 16a and 16b Adhesive layer 20 Anti-counterfeit paper 21 Base paper 22a Paper material 26 Exposed part 27 Cover part 28 Watermark part 29 Peeling part 29a Convex part of perforated net

Claims (5)

A thread for embedding in anti-counterfeit paper and using it, and having a film thickness of 0.01 to 0.1 μm on the surface of the base material in order to fill fine irregularities existing on the base material surface made of a resin film A surface smooth layer made of metal is provided, and a ferromagnetic material thin film layer having a squareness ratio of 0.7 to 1.0 is formed on the surface smooth layer with a thickness of 50 nm to 500 nm. An anti-counterfeiting thread characterized by being patterned by partial removal by a thin film removing means such as a laser processing method, an etching method, or a lift-off method . Claim 1 anti-counterfeit thread according to the bar code mark and being provided with patterned. An anti-counterfeit paper, wherein the anti-counterfeit thread according to claim 1 or 2 is engraved on a base paper. 4. The forgery prevention according to claim 3 , wherein the base paper includes an exposed portion that intermittently exposes the thread and a covering portion that intermittently covers the thread between the exposed portions. Paper. The anti-counterfeit paper according to claim 4 , wherein a plurality of exposed portions and covering portions are provided, and a plurality of anti-counterfeit threads are incorporated.

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