JPH11157016A - Laminate, manufacture thereof, and matter to be detected using the laminate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a good preventive property of forgery and alteration at low cost by taking reticular matter containing a magnetic substance by a specific range of wt.% and laminating a film on at least one surface thereof. SOLUTION: The laminate is formed by making an adhesive layer with reticular matter including at least a magnetic substance of 1-90 wt.%, and laminating a film on at least one surface thereof. From the laminate, a random signal is obtained, which originates from the form of reticular matter. Such a magnetic signal has a diverse pattern output, and so on every part of the laminate, so that it can be regarded as a fingerprint. The existence of the fingerprint can prevent the forgery and alteration of the laminate. Also, the reticular matter has an adhesiveness per se relative to the film to be an adhesive layer in the laminate, thus forming reticular matter on the directly. Therefore, a laminate can be obtained at low cost suitable for preventing forgery and alteration.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a low-cost laminated body having a function of preventing forgery and falsification by laminating irregular-shaped nets, a method of manufacturing the same, and the authenticity of cards and various securities using the same. The present invention relates to an object to be authenticated which needs to be determined.

[0002]

2. Description of the Related Art Various cards (for example, prepaid cards,
Cash cards, ID cards, etc.) and various securities are required to have high security, and forgery and falsification prevention functions are important. Conventionally, as one means for preventing forgery and alteration, a card or a base material to which random information is added has been proposed.
For example, Japanese Patent Laid-Open No. 6-2
JP-A-78391 and JP-A-7-32777 disclose information recording media and cards containing magnetic fibers.
In JP-A-270180, a card coated with a magnetic pigment in a non-uniform manner is disclosed. In JP-A-3-162715, a film in which magnetic particles are added in a non-uniform manner is disclosed in JP-A-6-87288.
In Japanese Patent Application Laid-Open Publication No. H11-139, there is proposed a document in which a metal thin film is formed on a continuous mesh hot melt adhesive.

[0003]

Among the above-mentioned conventional methods, in the method using a fibrous material, a fiber diameter and a fiber density can be arbitrarily adjusted, so that a signal suitable for preventing forgery and alteration is easily provided. However, the above-mentioned method using a fibrous material requires a separate step of manufacturing the fibrous material and a step of laminating the fibrous material on a film, which is expensive due to processing costs and the like. Also, the method using a continuous network hot-melt adhesive has the same problem because a metal thin film forming process is separately required.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned disadvantages of the prior art, to provide a laminated body having excellent anti-counterfeit and alteration properties at a low cost, a method of manufacturing the same, and an object to be authenticated which is made of the same. To provide.

[0005]

Means for Solving the Problems In view of the above problems, the present inventors have conducted intensive studies, and as a result, have found that the above problem can be solved by a laminated body in which a specific mesh material and a film are laminated and a manufacturing method thereof. Invented the invention. That is, the laminate according to the present invention is characterized in that a network containing at least 1 to 90% by weight of a magnetic material is used as an adhesive layer, and a film is laminated on at least one surface thereof.

[0006] The method of manufacturing a laminate according to the present invention comprises:
A method comprising melting a magnetic material-containing polymer composition, extruding it into a fiber form, spraying it on a first film with hot air to form a mesh, and further laminating a second film on the mesh. Consists of

In another method for producing a laminate according to the present invention, a magnetic material-containing polymer composition is melted, extruded into a fiber shape, and sprayed on a first film with hot air to form a net-like material. Furthermore, the method comprises laminating a sheet-like molten polymer on a mesh.

Further, the object to be detected according to the present invention, which is determined to be true or false, may be provided with a printed layer and / or a magnetic recording layer on the surface of the above-mentioned laminate, It is characterized by being embedded in a detection object as a strip and attached to the surface thereof.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. The laminate of the present invention is composed of a net containing a magnetic material and a film laminated on at least one side thereof, and a random magnetic signal derived from the form of the net is obtained from the laminate. Such a magnetic signal has a different pattern, output, and the like for each portion of the laminated body, and can be regarded as a fingerprint. Since the present laminate has such fingerprints, forgery and falsification can be prevented.

In order to provide a magnetic signal suitable for preventing forgery and falsification in the laminate of the present invention, it is necessary that the reticulated material contains at least 1 to 90% by weight of a magnetic substance. However, it is not necessary to include a magnetic material in all of the meshes. For example, a portion containing a black pigment may be included as a dummy, or a portion containing no black pigment may be included. What is necessary is just to contain 1 to 90% by weight of the magnetic material as the whole net. If the content of the magnetic material is less than 1% by weight, the S / N ratio is poor because the magnetic signal is weak, while
If the content is more than 10% by weight, the adhesion between the network and the film will be poor, and it will be difficult to provide a network structure. A more preferable content of the magnetic substance is 5 to 80% by weight.

The mesh in the present invention preferably has a structure in which fibrous materials are entangled from the viewpoint of giving a magnetic signal suitable for preventing forgery and falsification.
It is in the range of 200 microns, and the basis weight is 1-100.
It is preferably in the range of g / m ² .

The net in the present invention has adhesiveness to the film itself and becomes an adhesive layer in the laminate. As described above, since the mesh also serves as an adhesive for the laminate, the structure is simple, and further, a mesh structure can be directly formed on the film. The network can be formed by extruding a polymer composition containing a magnetic substance into a fiber form and spraying it with hot air. At this time, if the network has an adhesive property, the network can be formed directly on a film. on the other hand,
If the net has no adhesiveness, the net is blown off without being collected on the film. As described above, a laminate suitable for preventing forgery and falsification can be obtained at low cost by using a net having adhesiveness to a film.

In the present invention, the mesh is preferably composed of a hot-melt adhesive, and its melting point or its softening point is 50 ° C. or more, and its melting point or its melting point is 20 ° C. or more lower than its melting point or its softening point. This is preferable from the viewpoints of adhesiveness to the film, heat resistance of the laminate, and suitability for the production process of forming a net material directly on the film. As a type of the hot melt adhesive, for example, EV
A type, polyester type, polyamide type, polyolefin type, polyurethane type and the like can be used, and are appropriately selected according to the film material. For example, when the film is made of polyester, a polyester hot melt adhesive can be preferably used.

In the present invention, as the material of the film, polyester is preferred from the viewpoint of strength and dimensional stability, and polyethylene terephthalate and polyethylene naphthalate are particularly preferred. Further, this film is preferably a white film for hiding the network structure and for printing on the surface.

In the present invention, the type of the magnetic material is not particularly limited, but γ-iron oxide, cobalt-coated γ-iron oxide, chromium dioxide, barium ferrite, iron, nickel, and alloys thereof, which are conventionally used generally, are used. It can be used preferably. The form of the magnetic material may be particulate, fibrous, but if it is particulate, the particle diameter is 0.01 μm.
The range of m to 5 μm is preferred from the viewpoint of dispersibility. The magnetic material-containing polymer composition serving as a raw material of the network is obtained by melt-kneading the magnetic material and a polymer such as a hot melt adhesive.

Next, a method of manufacturing a laminate according to the present invention will be described. In the method for manufacturing a laminate of the present invention, the magnetic material-containing polymer composition is melted and then extruded into a fibrous form, which is sprayed on the first film by hot air to form a mesh, and the second mesh is further formed on the mesh. Lay the films together.

In order to form such a net, a melt blown nonwoven fabric manufacturing apparatus can be basically used. That is, the molten magnetic material-containing polymer composition is extruded into a fibrous form from a die, hot air is blown from a peripheral portion of the die, the fibers extruded by the hot air are made finer, and then the first is placed at an appropriate position. They are sprayed and collected on a film to form a net. In addition, by appropriately adjusting the discharge amount of the magnetic material-containing polymer composition, the hot air temperature, the hot air flow rate, the moving speed of the first film, and the like, the basis weight and the single-fiber fineness of the mesh can be arbitrarily set. it can.

As described above, a mesh formed of a hot-melt adhesive or the like has an adhesive property to a film and can form a network structure directly on the film. In the present invention, the second film can be adhered by laminating the mesh after forming the mesh, further utilizing the adhesiveness of the mesh. In this case, in order to ensure adhesion, the second film may be laminated and then pressure-bonded with a heating roll. If it is desired to use the laminate of the present invention in a configuration consisting of a first film and a mesh, the second film may be a release film. As described above, in the production method according to the present invention, since the formation of the mesh and the production of the laminate can be performed at the same time, a laminate excellent in anti-counterfeiting and alteration prevention at low cost can be obtained.

In the production method of the present invention, there is a method of laminating a sheet-like molten polymer instead of the second film. This is suitable for a case where a laminate is manufactured at once in the film forming process, and as described above, a laminate having low cost and excellent anti-counterfeiting and alteration prevention properties can be manufactured.

In the production method according to the present invention, after laminating the second film on the mesh or laminating the sheet-like molten polymer on the mesh, the laminate is stretched in at least one axial direction. Is preferred. According to such a manufacturing method, a web-like structure resulting from stretching can be imparted to the mesh, and the magnetic signal obtained from the laminate can be further complicated. The stretching method may be a roll method performed between rolls having different peripheral speeds or a tenter method. The stretching may be performed not only in the uniaxial direction but also in the biaxial direction. In this case, a sequential biaxial stretching method or a simultaneous biaxial stretching method can be used. After stretching, heat treatment is preferably performed from the viewpoint of the shape stability of the laminate, and is preferably performed for 0.5 seconds to 60 seconds.

In the present invention, the detection object to be determined as authenticity may be a form in which a printed layer and / or a magnetic recording layer is provided on the surface of the laminate of the present invention as a base material, or a strip of the present invention in a strip shape. Embedded in an object to be detected or attached to the surface. By using the laminate of the present invention, random magnetic information can be given to an object to be detected, and the effect of preventing forgery and alteration is enhanced. Further, the information obtained from the magnetic signal and the price information can be combined in the prepaid card. For example, there is a method in which information on a combination of money and magnetic signal is recorded in a card and the money information is restored from the magnetic signal. If you deform the unique code by punching the random information part every time you use the card,
Unauthorized use of the card becomes significantly more difficult.

The object of the present invention for which the authenticity is determined includes:
A dummy layer may be added with a low coercivity layer on the surface to make forgery more difficult, or a high permeability layer may be provided on the laminate surface so that random magnetic signals are usually shielded. You may keep it.

[Measurement Method of Characteristics] Each characteristic in Examples and Comparative Examples described later was measured by the following method. (1) Melting Point of Network The polymer constituting the network was weighed in an amount of 10 milligrams, and the heat of crystal fusion was measured using a differential scanning calorimeter RDC220 manufactured by Seiko Denshi Kogyo KK. The peak temperature was defined as the melting point.

(2) Formability of network The melted polymer composition containing a magnetic material is sprayed on a film, and a circle is formed when a network structure is formed, a triangle is formed when there is a discontinuous part, a blow-off or a network is formed. When the structure could not be formed, it was evaluated as x. In addition, x was rejected.

(3) Fiber Diameter A small piece of a mesh material is sampled, vapor-deposited with platinum / palladium, and observed and photographed by a scanning electron microscope. The fiber diameter in the photograph was measured, and the average value of 100 fibers was defined as the fiber diameter.

(4) Weight per unit area The film to which the mesh was adhered was sampled into a square having a side of 10 cm, and the weight was measured. The basis weight of the reticulated material was converted into a weight of 1 m square obtained by subtracting the weight of the film.

(5) Interlayer Adhesion Using a tensile tester, the surface film of the laminate was held on one chuck and the back film was held on the other chuck, and a peeling test was performed by pulling. The peel strength of a sample prepared under the exact same conditions with a hot melt adhesive containing no magnetic material is assumed to be 100, and if the peel strength containing a magnetic material is 80 or more, 、, 60 or more 80
Is less than 60, and x is less than 60. In addition, x was rejected.

(6) Magnetic Signal Strength The laminate was cut into a rectangle of 15 cm × 5 cm in size and magnetized by a 1000 gauss permanent magnet. The magnetized sample is an audio head (Sony CP21)
00) at a speed of 2.4 cm per second in the longitudinal direction of the laminate to perform reproduction. The reproduced output was input to a digital oscilloscope VP5720A manufactured by Panasonic Corporation, and an output larger than the noise output was detected as a magnetic signal.
When the magnetic signal strength is three times or more of noise, ○ when less than three times and two times or more, × when less than two times
And In addition, x was rejected.

[0029]

The present invention will be described more specifically with reference to examples and comparative examples. (Production of white polymer) Anatase-type titanium oxide particles having an average particle diameter of 0.3 μm are 15 parts by weight, and polyethylene terephthalate chips having an intrinsic viscosity of 0.65 dried at 180 ° C. for 4 hours are 85 parts by weight. Mix 2
Melt kneading was performed at 280 ° C. using a shaft kneader. The melt-kneaded polymer was drawn out in a gut shape, quenched in water, and then cut into chips by a cutter. Thus, a white polymer was obtained.

Comparative Example 1 (Production of Polymer Composition Containing Magnetic Material) Barium ferrite particles having an average particle diameter of 0.5 μm were used as a magnetic material, and “Byron G” manufactured by Toyobo Co., Ltd. was used as a hot melt adhesive.
Before kneading, the magnetic material was vacuum-dried at 200 ° C. all day and night, and the hot-melt adhesive was vacuum-dried at 70 ° C. all day and night. The kneading was 0.8 parts by weight of the magnetic material and 99.2 parts by weight of the hot-melt adhesive. And melt-kneaded using a twin-screw kneader at a temperature of 130 ° C. The melt-kneaded material is drawn out in a gut shape, quenched in water, wound up, and further crystallized at room temperature for about 8 hours. After that, the mixture was cut into chips by a cutter, thus obtaining a magnetic material-containing polymer composition.

(Production of a laminate)
For 4 hours, and was supplied to a first extruder and extruded from a T-die to obtain an unstretched film. On the other hand, the magnetic material-containing polymer composition vacuum-dried at 70 ° C. all day and night was charged into a second extruder and heated and melted at 160 ° C. The molten magnetic material-containing polymer composition was extruded into a fibrous form from a die having a pore diameter of 0.6 mm and 100 holes, and was sprayed onto the unstretched film while blowing hot air at 200 ° C. from around the die to form a net. . Furthermore, an unstretched white film was obtained by extruding the white polymer also from the third extruder, and was superposed as a second film on the mesh. The laminate thus obtained is further stretched 3.5 times in the longitudinal direction while being heated to 95 ° C. by a roll-type stretching machine, and then horizontally stretched to 95 ° C. by a tenter-type stretching machine.
It was stretched 5 times. The stretched laminate is subsequently 200 ° C.
At a temperature of In this way, a laminate having a front and back film thickness of 75 microns was obtained. The results are shown in Table 1. As a result, the magnetic signal was weak because it did not satisfy the range of the present invention, and it was rejected.

Comparative Example 2 A laminate was obtained in exactly the same manner and under the same conditions as in Comparative Example 1, except that the content of the magnetic material was changed to 95% by weight. The results are shown in Table 1. As a result, a net could not be formed because the magnetic substance content was too large, and a granular discontinuous layer was formed. In addition, the adhesion between the layers was insufficient, and the test was rejected.

Examples 1 to 3 Laminates were obtained in exactly the same manner and under the same conditions as in Comparative Example 1, except that the content of the magnetic material was changed. The results are shown in Table 1,
The network formability, the interlayer adhesion, and the magnetic signal strength were all acceptable, and the intervals and output values of the magnetic signals differed for each part of the laminate and were random.

Example 4 (Production of polymer composition containing magnetic substance)
A magnetic material-containing polymer composition was obtained in the same manner and under the same conditions as in Comparative Example 1 except that the content was changed to% by weight.

(Production of laminate)
For 4 hours and fed to the first extruder. After the white polymer was extruded from the T-die to obtain an unstretched film, the film was further stretched 3.5 times in the longitudinal direction while heating to 95 ° C. with a roll-type stretching machine to obtain a uniaxially stretched film. on the other hand,
The magnetic material-containing polymer composition vacuum-dried at 70 ° C for 24 hours was charged into a second extruder, and heated and melted at 160 ° C. The melted magnetic material-containing polymer composition was extruded into a fibrous form from a die having a hole diameter of 0.6 mm and 100 holes, and sprayed onto a uniaxially stretched film while blowing hot air at 200 ° C. from around the die to form a net. . Further, a white polymer was extruded from the third extruder, and the sheet-like molten polymer was laminated on a net. The laminate thus obtained was subsequently stretched 3.5 times in the transverse direction while being heated to 95 ° C. by a tenter-type stretching machine. The stretched laminate was subsequently heat-treated at a temperature of 200 ° C. In this way, a laminate having a front and back film thickness of 75 microns was obtained. The results are shown in Table 1.
Both the interlayer adhesion and the magnetic signal strength were acceptable, and the intervals and output values of the magnetic signals differed for each part of the laminate and were random.

Examples 5 and 6 Laminates were obtained in exactly the same manner and under the same conditions as in Example 4, except that the basis weight of the nets was changed by changing the line speed of film formation. Table 1 shows the results.

Examples 7 and 8 A magnetic material-containing polymer composition was obtained in exactly the same manner and under the same conditions as in Comparative Example 1, except that the content of the magnetic material was changed to 10% by weight. A laminate was obtained in exactly the same manner as in Comparative Example 1, except that the flow rate of hot air and the film forming line speed when forming the mesh were changed to change the fiber diameter and the basis weight of the mesh. Table 1 shows the results.

[0038]

[Table 1]

From Table 1 above, it can be seen that a net having a magnetic substance content of 1 to 90% by weight can provide a laminate having excellent interlayer adhesion and magnetic signal strength. Further, it can be seen that the production method of the present invention enables the formation of a network and the production of a laminate in the film forming step.

Example 9 One side of each of the laminates obtained in Examples 1 to 8 was coated with a magnetic paint in a stripe shape using a gravure roll. The magnetic paint was prepared as follows.・ 100 parts of γ-Fe ₂ O ₃ Average particle size (length): 0.3 μm Needle ratio: 10/1 Coercive force: 500 Oe ・ 15 parts of polyurethane resin ・ 5 parts of vinyl chloride / vinyl acetate copolymer ・ nitrocellulose Resin 5 parts ・ Alumina powder 3 parts Average particle size: 0.3 μm ・ Carbon black 1 part ・ Lecithin 2 parts ・ Methyl ethyl ketone 100 parts ・ Methyl isobutyl ketone 100 parts ・ Toluene 100 parts ・ Stearic acid 2 parts

After the above composition is dispersed and mixed in a ball mill for 48 hours, a kneaded product obtained by adding 6 parts of a curing agent is filtered through a filter to prepare a magnetic coating solution. Coating is performed using a gravure roll, and the magnetic field is oriented at 100 ° C.
, And calendered with a small test calender, and cured at 70 ° C. for 48 hours to obtain a magnetic card.

After reading the magnetic signal of the film portion, it was converted into a code by digital conversion, and the code was recorded on a magnetic stripe to obtain a card whose authenticity was correctly determined.

[0043]

The laminate of the present invention comprises a net containing at least 1 to 90% by weight of a magnetic material as an adhesive layer and a film laminated on at least one side thereof. It has a signal. Further, the production method of the present invention, after melting the magnetic material-containing polymer composition, extruded into a fibrous form, sprayed on the first film by hot air to form a mesh, and further a second film on the mesh. After laminating or melting the magnetic material-containing polymer composition, extruding it into a fibrous form, spraying it on the first film with hot air to form a mesh, and then laminating the sheet-like molten polymer on the mesh Thus, the laminate can be manufactured at low cost. According to the above-described laminate and manufacturing method, a card or the like having a high anti-counterfeit and alteration prevention effect can be provided at low cost.

Claims (7)

[Claims] 1. A laminate comprising a network containing at least 1 to 90% by weight of a magnetic material as an adhesive layer, and a film laminated on at least one surface thereof. 2. The laminate according to claim 1, wherein the mesh comprises at least a hot melt adhesive. 3. A method of melting a magnetic material-containing polymer composition, extruding it into a fibrous form, spraying it on a first film with hot air to form a mesh, and further laminating a second film on the mesh. A method for producing a laminate, characterized in that: 4. The method for producing a laminate according to claim 3, wherein the laminate is stretched in at least one axial direction after the second film is overlaid. 5. A method in which a magnetic material-containing polymer composition is melted, extruded into a fibrous form, sprayed on a first film by hot air to form a mesh, and a sheet-like molten polymer is further laminated on the mesh. A method for producing a laminate, characterized in that: 6. The laminate is stretched in at least one direction after laminating the sheet-like molten polymer.
The method for producing a laminate according to the above. 7. A method according to claim 1, wherein a printed layer and / or a magnetic recording layer is provided on the surface of the laminate according to claim 1 or the laminate is detected as a strip. An object to be authenticated, which is buried in an object or attached to the surface thereof.