JPH0698860B2 - Method for manufacturing substrate of card-like document requiring authenticity - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is applicable to securities, prepaid cards, horse racing voting tickets,
The present invention relates to a method for manufacturing documents requiring authenticity such as expressway pass tickets, parking tickets, railway tickets, banknotes, passports, credit cards, bonds, certificates, and other substitutes for banknotes.

[Prior Art] It is important for documents requiring authenticity to have a function of preventing forgery and falsification.

As a technique for preventing such forgery and tampering, it has been proposed to hold a conductive fiber in a document (see, for example, Japanese Patent Application Publication No. 63-501250).

In this technique, conductive fibers are randomly distributed and held on a document substrate made of a non-conductive material, and the distribution state of the conductive fibers is recorded on the document by means such as magnetic recording, or Record in an external storage device. When checking the authenticity of a document, the distribution state of the fibers on the document is detected by irradiating the document with microwaves, etc. and detecting its reflection or transmission with a detector. Is compared with the recorded content that records the reference distribution state. If the document is modified or altered, the distribution state of the fibers on the document does not match the recorded content, so it can be determined that the document or the document base is not authentic.

[Problems to be Solved by the Invention] Since the technology for checking the authenticity of a document has random fiber distribution and no regularity, it is extremely difficult to restore or reproduce the fiber distribution after falsification of the document. And, in principle, it is an extremely excellent technology for preventing forgery and alteration.

However, the technology for actually producing such documents has not yet been established. In particular, this type of document needs to have durability to keep the conductive fiber in the distribution or shape at the time of document production, and it is desired to develop a highly productive document production technique that can be easily produced. ing. As a specific problem, it is difficult to obtain uniform distribution of fibers, and it is difficult to obtain a uniform distribution, and it is desired to solve this problem.

The present invention has been made in view of the above circumstances, and provides a method for manufacturing a document substrate which can reliably hold a conductive fiber in a document and requires authenticity with high productivity. The purpose is.

[Means for Solving the Problem] In order to achieve this object, the method for producing a substrate for a card-like document which requires the authenticity of the present invention is a method in which a bundle of conductive fibers having a diameter of 0.025 mm or less is solid at room temperature. And a fiber / plastic composite impregnated with a resin that is compatible with the molding resin made of a non-conductive material,
Mix the columnar member cut to a length of 0 mm with the molding resin,
It is characterized by including a step of forming this into a sheet.

[Operation] When the document base is made of the molding resin containing the conductive fibers, the document base holds the conductive fibers in a unique distribution. By confirming this distribution, the authenticity of the document can be confirmed. Can be determined.

[Examples] Examples in which the base material of the present invention is applied to a card surface base material of a certification card will be described below.

In FIGS. 1 and 2, reference numeral 1 denotes a certification card base as an example of a document base requiring authenticity, which is an object for carrying out the manufacturing method of the present invention.

The certification card base 1 has a card base 2 and the card base 2
A magnetic film 5 is applied to the entire surface or a required portion of the surface of the above, and further necessary printing 6 and the like are performed.

A conductive fiber 8 is embedded and held in the card base material 2.

As will be described later, the card substrate 2 is a mixture of non-conductive transparent or opaque molding resin pellets such as polyvinyl chloride, polyolefin, polycarbonate, polyester such as polyethylene terephthalate, and columnar members of fiber / plastic composite, It is molded into a sheet with a thickness of 50 μm to 2.0 mm.

The conductive fiber 8 has an electromagnetic characteristic different from that of the card substrate 2. That is, the conductive fiber 8 is different from the card substrate 2 in the relative permittivity ε, the magnetic permeability μ, the resistivity ρ, or other values that affect the microwave. The conductive particles 8 are metal, carbon, polymer fiber coated with metal, and preferably have a length of 0.1 m.
It has a diameter of 2 μm to 25 μm and a distribution density on the card surface substrate 2 of about 5 to 300 g / m ² .

Such a card base material is manufactured by the following manufacturing method.

About 20% to 70% of conductive fiber as shown in Fig. 3
The fiber / plastic composite 21 contained in the above range is supplied into the hopper of the mixer 23 with a predetermined amount of molding resin pellets 22. The molding resin pellets 22 are plastic pellets containing no fiber and, if necessary, contain a coloring agent such as a white pigment.

The mixture is fed to the hopper of the extruder 24, and the plastic material is heated in the extruder 24 to be softened and kneaded so that the fibers are uniformly dispersed, and the screw is passed through a suitable orifice, channel or slot to a die 25. The card base material 2 can be obtained by being sent out, extruded into a sheet shape by the die 25, and given a smoothness by a roll if necessary.

As shown in FIG. 4, the fiber / plastic composite 21 is made up of a bundle of long conductive fibers 8 and a resin material 27 impregnated in the bundle, and as shown in FIG. A resin material 28 may be provided to cover the entire circumference of the resin material 27. This is cut to a length of 0.1 mm to 30 mm and mixed with pure plastic pellets. The bundle of the conductive fibers 8 is composed of 1000 to 20000 conductive fibers, and the volume ratio in the impregnated resin material 27 is 20 to 70%. The resin materials 27 and 28 are both made of a resin that is compatible with the molding resin, and the same or different kind of molding resin is used.

In the case of the same kind, it is possible to use a relatively low molecular weight one, or to use a plasticizer together.
Alkyd resin etc. can be used. This resin material is a solid at room temperature and dissolves in a solvent, and examples thereof include alkyd resin, polyester resin, polystyrene, and polyamide. These resin materials can be made into a fiber / plastic composite by dissolving or dispersing in an organic solvent or water, impregnating a bundle of conductive fibers, and removing the solvent at room temperature or by heating. In this case, the resin may be melted by heating without a solvent, impregnated in the same manner, and then cooled and solidified.
The same applies to covering the columnar member.

The card substrate 2 manufactured in this way is used as follows in the document manufacturing process to form a document such as a certification card.

As shown in FIG. 6, the card substrate 2 may be a web rewound, or a sheet-like sheet may be used. The card substrate 2 may be subjected to desired printing (card substrate supplying step (FIG. 6 (a))).

Next, if necessary, the magnetic film 5 is formed on the outer surface of the card substrate 2 (magnetic film forming step (FIG. 6 (b))).

As a technique for forming the magnetic film 5, for example, there is a printing method using magnetic ink and a method of adhering a magnetic tape.

In this way, the certification card base 1 is completed.

The certification card substrate thus formed is wound on a reel and stored until it is cut into a card shape (winding step (FIG. 6 (c))). Alternatively, it is cut into card dimensions (cutting step (FIG. 6 (d))).

As another embodiment, as shown in FIG. 7, a card base 1a may be constructed in which the card base 2 is sandwiched by oversheets 7a and 7b from both sides. Further, the surface of the card substrate 2 may be printed or painted.

Although not shown, it is also a practical method to co-extrude plastic on one or both sides to form a laminate when molding the card substrate 2.

Although the above-mentioned embodiment applies the base of the present invention to the card base of the certification card, the base of the present invention can be applied to other bases constituting other documents.

EFFECTS OF THE INVENTION In the present invention, the conductive fiber is kneaded and held in the document base material, so that no extra material is required for applying the conductive fiber and the increase in the number of steps can be minimized. it can.

In addition, the conductive fiber can be made invisible to the outside of the document base material, and is securely held so that the conductive fiber does not drop out or displace and the distribution state during manufacturing is maintained. A highly durable document can be produced.

Moreover, in the case of adjusting the molding resin containing the conductive fiber, if the cut fiber is directly added to the molding resin, the fibers cannot be sufficiently kneaded because of the entanglement of the fibers, but as in the present invention, A bundle that is solid at room temperature and impregnated with a resin that is compatible with the molding resin is cut into pellets that are added to the molding resin to form a uniform fiber without entanglement. It can be dispersed in the resin. Further, when the columnar pellets, which are solid at room temperature and coated with a resin compatible with the molding resin, are added to the molding resin, the columnar pellets are exposed to the cut surface etc. as they are. Entanglement between fibers occurs, but such entangling can be prevented and uniform dispersion can be achieved.

In such documents, the conductive fibers have a random and unique distribution, and the conductive fibers have different electromagnetic properties than the constituent materials of the document, such as relative permittivity ε, magnetic permeability μ, The resistivity ρ or other values affecting the microwaves are different, so that by detecting the reflection and transmission of the microwaves, the distribution of the respective conductive fibers can be detected. This distribution is also recorded on the document by magnetic or other means.

If a person who modified the document tried to tamper with this document, such as cutting the document base material, the distribution of the conductive fibers would change, and the distribution would be different from the one recorded on the document. Tampering can be detected.

[Brief description of drawings]

FIG. 1 is a perspective explanatory view of a certification card, FIG. 2 is a sectional explanatory view of II-II portion in FIG. 1, FIG. 3 is an explanatory view showing a manufacturing process of a base material of a card-like document, FIG. 4 and FIG. FIG. 5 is a perspective explanatory view showing a fiber / plastic composite, FIG. 6 is an explanatory view showing a manufacturing process of a certification card, and FIG. 7 is a cross sectional view showing a certification card base body according to another embodiment of the present invention. It is a figure. 1 ... Certificate card, 2 ... Card substrate, 5 ... Magnetic film, 6 ... Printing, 8 ... Conductive fiber, 21 ... Fiber / plastic composite, 22 ... Molding resin, 23 ... Mixer, 24 …… Extruder

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location G06K 19/10 G07D 7/00 9340-3E

Claims (2)

[Claims] 1. A fiber / plastic composite obtained by impregnating a bundle of conductive fibers having a diameter of 0.025 mm or less with a resin which is solid at room temperature and compatible with a molding resin made of a non-conductive material. A method for manufacturing a base for a card-like document requiring authenticity, which comprises a step of mixing a columnar member cut into a length of 0.1 to 30 mm with a molding resin and molding this into a sheet 2. The columnar member according to claim 1, further comprising a columnar member which is solid at room temperature and which is covered with a resin having compatibility with the molding resin. For manufacturing a card-like document substrate requiring heat