JPH02167771A - Laminated paper decidable between truth and fake - Google Patents

Abstract

PURPOSE:To make possible the easy identification of an imitation product bearing a seemingly similar code by providing a code for determination of truth between the synthetic resin film and paper of laminated paper, making it difficult to determine whether or not the code exists from the surface and composing the code using the ink which does not allow transmission of a near infrared ray and the ink which allows transmission of the ray. CONSTITUTION:A card 1 is of a three-layer structure sandwiching a synthetic resin film 2 between two sheets of paper 3, 3, and has codes 4a, 4b for deciding between truth and fake between the paper 3 and the synthetic resin film 2. The code 4a indicates a code printed using the ink which does not allow transmission of near infrared rays, e.g. carbon black, while 4b indicates a code printed with the ink which allows transmission of the rays. The codes 4a, 4b need to be visually difficultly distinguished. A magnetic recording layer and a printing layer can be provided on the surface of the paper 3, if necessary. Furthermore, the magnetic recording layer can be provided on the surface of the paper 3 by applying its liquid in the form of stripes or over the entire surface.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a laminated paper in which counterfeit products can be easily identified by a simple method for determining authenticity.

(Prior Art) The base paper for cards is made by pasting paper on both sides of a synthetic resin film, and because it has superior durability and water resistance compared to plain paper, it is used for bankbook paper and the like. In addition, it is cheaper than thick polyester film, so it can be used for road passes,
It is used as the base paper for train tickets, disposable prepaid cards that can be used only a limited number of times, etc. Conventionally, when providing anti-counterfeiting functions to paper, plastic films, etc., identification information is provided on the printed layer, magnetic recording layer, etc. on the surface of these materials. However, with these methods, the presence or absence of identification information can often be easily determined visually, and it cannot be said that the anti-counterfeiting ability is high.

(Problems to be Solved by the Invention) As described above, it has been difficult to produce cards with high anti-counterfeiting functions using conventional techniques. An object of the present invention is to provide a card that is inexpensive and cannot be easily reproduced by utilizing the characteristics of laminated paper.

(Means for Solving the Problems) The present invention involves bonding paper to at least one side of a synthetic resin film, and using at least two types of ink having different optical properties in the near-infrared region on the bonded surface. This is a laminated paper that can be used to determine authenticity, and is characterized by printing a code for determining authenticity.

The present invention involves bonding paper to at least one side of a synthetic resin film, printing a code for authenticity determination on the bonded surface using at least one type of ink, and coloring the synthetic resin film and/or paper. This is a laminated paper that can be authenticated and is characterized by being colored with an agent to form a colored film and/or a colored sheet, and having a coloring relationship with an authenticity determining code.

Examples of the laminated paper of the present invention include two-layer paper in which paper is bonded to one side of a synthetic resin film, and three-layer paper in which paper is bonded to both sides of a synthetic resin film.

As the synthetic resin film, polyethylene terephthalate film is preferred. The thickness of the film is usually 75-1
It is about 00 μm. Natural pulp paper is preferred as the paper adhered to both sides of the synthetic resin film. The thickness of paper is usually about 50 to 75 μm.

Examples of inks with different optical properties in the near-infrared light region include inks with different near-infrared light transmittances. Examples of inks with low near-infrared light transmittance include printing inks containing carbon, printing inks containing near-infrared light absorbing dyes, and the like. Examples of near-infrared light absorbing dyes include aluminum dyes such as IRG-002-1 manufactured by Nippon Kayaku Co., Ltd.
06 etc. are mentioned. In addition, inks with high near-infrared light transmittance include carbon and near-infrared light absorption inks.
The colors must be similar enough to be indistinguishable in the visible light range.

It is not desirable for the purpose of preventing counterfeiting to know that there is a difference in the visible light region.

The laminated paper of the present invention can be produced, for example, by the following method. (1
) After printing a code for authenticity determination on a synthetic resin film, paper is attached to both or one side of the film via an adhesive. Examples of printing methods used include offset printing, screen printing, and coating. As the adhesive, a polyurethane adhesive is preferred. In this case, paper without a code printed on it is used.

(2) After printing a code for authenticity determination on paper, the paper is pasted together so that the code-printed side is in contact with the synthetic resin film. When using three-layer paper, paste paper with no code printed on the other side of the film. (3) Knead coloring agent into synthetic resin film and/or paper in advance, impregnate it,
A colored film and/or colored sheet is formed using a method such as cutting or coating. Next, a code for determining authenticity is printed on the bonding surface of the synthetic resin film or paper, and the synthetic resin film and paper are bonded together.

At this time, the ink and colorant are selected so that the code and the near-infrared light transmittance of the colored film and/or colored sheet are related to light. Note that in this case, it is preferable that the ink and the colorant have the same color tone.

This will be explained below with reference to the drawings. Figure 1 is a partial vertical cross-sectional view of a card made using three-layer paper. Card 1 has a three-layer structure in which synthetic resin film 2 is sandwiched between paper 3 and paper 3. Authenticity determination code 4a between film 20
, 4b. 4a is a code printed with ink that does not transmit near-infrared light, such as ink containing carbon black;
b may be printed with an ink that transmits near-infrared light to provide a magnetic recording layer, a printed layer, etc. The magnetic recording layer may be provided on the surface of the paper 6 in the form of stripes or by coating the entire surface.

FIG. 2 is a plan view of the card 1, in which a code 4a printed with ink that does not transmit near-infrared light and a code 4b printed with ink that transmits near-infrared light are arranged alternately. shows.

Figure 6 shows the synthetic resin film 2 and the colored film!・It is a partial longitudinal cross-sectional view of a card made using a two-layer paper composed of 6′. In this case, a code 4a printed with ink that does not transmit near-infrared light is present on the adhesive surface of the synthetic resin film 2 and the colored sheet 6'.

FIG. 4 is a partial longitudinal cross-sectional view of a card made using three-layer paper in which paper 3 is pasted on one side of synthetic resin film 2 and colored sheet 3' is pasted on the other side. In this case, the symbol 4a is placed on the bonding surface of the synthetic resin film 2 and the colored sheet 6'.
exists.

FIG. 5 is a process diagram for determining the authenticity of a card, in which an LED (light emitting diode) 5 that emits near-infrared light also irradiates near-infrared light, and the near-infrared light reaches a photodiode 6. is converted into a current, and this change is recorded by a recording device 8 via an amplifier 7. The card 1 passes between the LED 5 and the photodiode 60 at a constant speed.

FIG. 6 is a graph showing changes in the output of the amplifier that appear when the card 1, which has six symbols 4a printed with ink that does not transmit near-infrared light, passes between the LED 5 and the photodiode 60 at a constant speed. Yes, the horizontal axis of the graph shows time and the vertical axis shows output (voltage). When the card 1 reaches between the LED 5 and the photodiode 6 (T1), the near-infrared light sensed by the photodiode 6 decreases, so the output also decreases. When the code 4a printed with ink that does not transmit near-infrared light passes between the LED 5 and the photodiode 6 (T, , T5, T4), the output decreases significantly. However, when the code 4b printed with ink that transmits near-infrared light passes between the LED 5 and the photodiode 6, the output hardly changes. When the card 1 then passes between the LED 5 and the photodiode 60, the output returns to its original level.

Example 1 A barcode was offset printed on a 100μ thick polyester film using a carbon pigment type ultraviolet curable black offset ink, and a dummy barcode was printed on one side using a dye type ultraviolet curable black offset ink. was offset printed. Next, a polyurethane adhesive was applied to the side of the polyester film on which the barcode was printed to a thickness of approximately 5 μm, and the film was bonded to paper having a thickness of 50 μm. Similarly, apply polyurethane adhesive to the opposite side of the polyester film to a thickness of approximately 5 μm, and
This was laminated with μ paper to obtain a three-layer laminated paper with a thickness of approximately 210 μm. When we punched out the laminated paper produced in this way into cards and created cards with barcodes on them to prevent counterfeiting, we found that the real barcodes were made using carbon pigment-type ink, and the cards were made using dye-type ink. □−
The barcode was difficult to distinguish visually. However, when passing near-infrared light between an LgD that emits light and a photodiode, the output of the photodiode is attenuated in the real barcode area, but no output attenuation occurs in the dummy barcode area. These two types of barcodes could be distinguished.

Example 2 A bar code was offset printed using a polyester film having a thickness of 125 μm and a carbon pigment type ultraviolet curable black offset ink. Next, polyurethane adhesive was applied to the side of the polyester film on which the barcode was printed to a thickness of about 5 μm, and the film was bonded to a 75 μm thick paper that had been colored with black dye at the time of paper making, resulting in a thickness of about 2°. 5μ
A laminated paper with a two-layer structure was obtained. When the thus produced laminated paper was punched into a card shape and a barcode was created to prevent forgery, the barcode was difficult to distinguish visually. However, when it was passed between LlliD, which emits near-infrared light, and a photodiode, the output of the 7 photodiodes was attenuated at the barcode area, making it possible to identify the barcode.

Example 3 A barcode was offset printed on a polyester film with a thickness of 100 μm using a carbon pigment type ultraviolet curable black offset ink. Next, a polyurethane adhesive was applied to the side of the polyester film on which the barcode was printed to a thickness of approximately 5 μm, and the film was bonded to a 50 μm thick paper that had been colored with black dye during paper making. Similarly, a polyurethane adhesive was applied to the opposite side of the polyester film to a thickness of approximately 5 μm, and the adhesive was laminated to a 50 μm thick uncolored paper to obtain a three-layer laminated paper 1 having a thickness of approximately 210 μm. . The laminated paper produced in this way was punched out into card shapes and cards with barcodes were created to prevent counterfeiting.
Barcodes were difficult to distinguish visually. However, when the light was passed between an LED that emits near-infrared light and a photodiode, the output of the photodiode was attenuated at the barcode area, making it possible to identify the barcode.

(Effects of the Invention) In the present invention, since a code for authenticity determination is provided between the synthetic resin film of the laminated paper and the paper, it is difficult to tell from the surface whether or not there is a code, and the code also uses ink that does not transmit near-infrared light. Since it is made of ink that transmits near-infrared light, counterfeit products with visually similar codes can be easily identified.

[Brief explanation of the drawing]

Figure 1 is a partial longitudinal cross-sectional view showing an example of a card made of three-layer paper made by pasting paper on both sides of a synthetic resin film.
The figure is a plan view of the card, Figure 3 is a partial vertical cross-sectional view of an example of a card made from two-layer paper with a colored sheet pasted on one side of a synthetic resin film, and Figure 4 is a partial vertical cross-sectional view of one side of the synthetic resin film. Partial longitudinal sectional view showing an example of a card made of three-layer paper with paper on one side and a colored sheet on the other side, Part 5
The figure is a process diagram of the authenticity determination method. Figure 6 shows that the card with three codes printed with ink that does not transmit near-infrared light is an LED.
This is a graph showing the change in the output of the amplifier that appears when passing between the photodiode and the photodiode. In the figure, symbol 1 is a card using laminated paper, 2 is a synthetic resin film, 3 is paper, and 3' is a colored card. Sheets, 4a and 4b are truth determination codes, 5
indicates an LED, 6 a photodiode, and 7 an amplifier. Figure 1 2 Applicant: 1 representative from Sanyo Electric Manufacturing Co., Ltd. Patent attorney Atsushi Takahashi - Condolence S Diagram t Tz T374 Ts

Claims (1)

[Claims] 1. Paper is pasted on at least one side of a synthetic resin film, and at least two types of ink having different optical properties in the near-infrared light region are used on the pasted surface to create a code for authenticity determination. A laminated paper that can be authenticated and is characterized by being printed with. 2. Paste paper on at least one side of the synthetic resin film, print a code for authenticity determination on the pasted surface using at least one type of ink, and coat the synthetic resin film and/or paper with a coloring agent. Colored and colored film and/or
Or, a colored sheet is formed, and the light transmittance of the authenticity determination code and the colored film and/or the colored sheet in the near-infrared light region is such that the light transmittance of the code<the colored sheet and/or<the light transmittance of the colored film. A laminated paper whose authenticity can be determined, and which is characterized by the following relationship.