JPH0796656A - Information record medium - Google Patents

Abstract

PURPOSE:To effectively prevent a forgery, a falsification without being restricted in a design of a medium by recording invisible information such as characters, numeric characters, a bar coder, etc., by a thermal head, a laser beam, direct writing, etc., and reading its information itself, though it is invisible, by a machine. CONSTITUTION:A thermal and pressure-sensitive record layer 2 containing dye precursor having remarkable light absorption on an IR region without almost altering absorption of a visible region when in contact with an electron accepting substance is provided on at least one side of a support, a decorative print layer 3 such as characters, ground ting, etc., of ink for absorbing a light of a visible region and transmitting a light of an IR region is provided on the layer 2 as required, and further heat resistant protective layers 4 are provided on the players 2 and 3 as required.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to securities such as prepaid cards, pass tickets, admission tickets, tickets, computer output paper, fax paper and other forms and OA materials, bar codes and OCR characters. The present invention relates to an information recording medium used for things that impair the aesthetics of the product itself when such items are placed on the surface of the product, which can be recorded by a thermal head, laser beam, direct writing, etc., and the information itself. The present invention relates to an information recording medium which is invisible but can be read by a machine.

[0002]

2. Description of the Related Art In recent years, there have been remarkable developments in information recording media such as prepaid cards, pass tickets, entrance tickets, tickets, and the like, in which machine-readable information is recorded, and they have been used in many fields. ing.

In this type of information recording medium, a magnetic recording layer is provided on a substrate and information is recorded on this magnetic recording layer. Although this magnetically recorded information is invisible to the naked eye, higher security is required for these information recording media. For example, in addition to the magnetic recording section, as a discriminating function for determining the authenticity of the information recording medium, a magnetic or a non-magnetic visible recording medium is arranged, or a concealment for concealing the magnetic recording layer of the magnetic recording section. The layers are formed so that the magnetic recording contents cannot be easily read from the outside.

By the way, in recent years, in addition to recording fixed information or identification information or variable information on the magnetic recording layer, in order to provide convenience to the owner of the information recording medium, visible information is recorded on the medium surface during use. With prepaid cards, in particular, the same value information as magnetic recording can be visually checked without reading the reader.

As a method of directly writing visible information on an information recording medium, a heat-sensitive recording layer using a leuco dye such as a fluoran dye as a color former and a phenolic compound as a color developer is provided on the information recording medium side. There is something to print.

Further, when recording information on such an information recording medium, a thermal head or a laser beam is used to cause a chemical change by thermal energy to record image information such as characters and figures. It is generally done. Some of these leuco dyes have remarkable light absorption in the infrared region when they are colored, and recently, a method of coding such information and mechanically reading it has begun to be used.

[0007] However, in such a color-forming infrared absorber, when it is used as an identification function other than magnetic recording, for example, it is easily recognized as an identification function body, and the problem of counterfeiting / tampering occurs. On the other hand, the effect may be halved.

Therefore, in such a case, it is possible to cope with the situation by recording / mechanically reading information invisible to the third party on the side of the information recording medium.

However, when optically invisible information is recorded, the design of the information recording medium itself is restricted because a filter layer that does not transmit visible light but transmits infrared light is generally provided. Furthermore, it is easily inferred that the identification function body as described above is applied, and there remains a problem in that it completely prevents counterfeiting and falsification.

[0010]

As described above, the conventional information recording medium has a problem that not only forgery and tampering cannot be prevented but also the design of the medium itself is restricted.

The present invention has been made to solve the above problems, and invisible information such as letters, numbers and bar codes can be recorded by a thermal head, a laser beam, direct writing or the like. To provide an extremely reliable information recording medium that makes it possible to read it by a machine, though it is invisible itself, and reliably prevent counterfeiting and tampering without being restricted by design. The purpose is to

[0012]

In order to achieve the above-mentioned object, first, an information recording medium of the invention corresponding to claim 1, when at least one of the supports is brought into contact with an electron accepting substance, The heat-sensitive / pressure-sensitive recording layer is provided with a dye precursor which has almost no change in absorption in the visible region and has a remarkable light absorption in the infrared region.

Further, in the information recording medium of the invention according to claim 2, the absorption in the visible region hardly changes when at least one of the supports is brought into contact with the electron-accepting substance, and the remarkable light in the infrared region is emitted. A heat-sensitive / pressure-sensitive recording layer containing a dye precursor with absorption is provided, and on this heat-sensitive / pressure-sensitive recording layer, an ink that absorbs light in the visible region but transmits light in the infrared region Is provided with a pattern printing layer.

Furthermore, in the information recording medium of the invention according to claim 3, when at least one of the supports is brought into contact with an electron-accepting substance, the absorption in the visible region hardly changes, and the remarkable light in the infrared region. Heat sensitive containing dye precursor with absorption
A pressure-sensitive recording layer is provided, and an ink that absorbs light in the visible region but transmits light in the infrared region is provided on the heat-sensitive / pressure-sensitive recording layer to provide a pattern printing layer such as letters and tint patterns. A heat-resistant protective layer is provided on the pressure-sensitive recording layer and the pattern printing layer.

Furthermore, the information recording medium of the invention corresponding to claim 4 is the information recording medium according to any one of claims 1 to 3, wherein at least one of the recording medium is heat-sensitive. A magnetic recording layer forming an information recording layer together with the pressure sensitive recording layer is provided.

[0016]

Therefore, in the information recording medium of the present invention, when at least one side of the support is brought into contact with an electron-accepting substance, the absorption in the visible region hardly changes and the dye having a remarkable light absorption in the infrared region. By providing a heat-sensitive / pressure-sensitive recording layer containing a precursor, invisible information such as letters, numbers, and bar codes which are not restricted by the design of the information recording medium,
It can be recorded by a thermal head, a laser beam, direct writing, etc., and the information itself is invisible, but can be read by a machine.

This makes it possible to provide an information recording medium that is extremely effective in preventing forgery and falsification without being restricted by design.

[0018]

[Examples] We have found that when a specific cycloalkene compound is dissolved in a solvent such as alkylbenzene in the presence of an electron-accepting substance, the absorption in the visible region hardly changes and the remarkable light absorption in the infrared region occurs. Found to have.

Therefore, in the present invention, a heat-sensitive / pressure-sensitive recording layer containing such a dye precursor is provided on a support made of paper, PET or the like, and if necessary, the heat-sensitive / pressure-sensitive recording layer. An ink that absorbs light in the visible region but transmits light in the infrared region is provided on top of it to provide a pattern printing layer for characters, tint block, etc., and if necessary, a heat-sensitive / pressure-sensitive recording layer and a pattern printing layer. An information recording medium is provided on which a heat-resistant protective layer for protecting the surface from a printing means such as a thermal head is provided.

An embodiment of the present invention based on the above concept will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing a structural example of a card-shaped information recording medium according to the present invention.

That is, in the information recording medium of this embodiment, as shown in FIG. 1, a heat-sensitive / pressure-sensitive recording layer 2 is provided on a support 1, and a pattern is formed on the heat-sensitive / pressure-sensitive recording layer 2. Print layer 3
And the heat-resistant protective layer 4 is further provided on the pattern printing layer 3.

Here, the support 1 is mechanically tough, flexible and flexible, for example, a polyethylene terephthalate film, a plastic film made of polycarbonate, polyvinyl chloride, or other polymer material, or an information recording medium. Papers such as papers, art papers, coated papers, metal plates and glass plates can be used as necessary.
Generally, a film having a thickness of 50 to 1000 μm and having heat resistance capable of withstanding a momentary high temperature of 250 ° C. or higher is suitable as a support for the present information recording medium.

The heat-sensitive / pressure-sensitive recording layer 2 is composed mainly of a dye precursor, an electron-accepting substance and a polymer binder, and microcapsules containing the electron-accepting substance and oil are used as a suitable solvent. The dispersion obtained by dispersing in a coating solution of the polymer binder dissolved by, for example, known coating such as solvent coating method such as bar coating, blade coating, air knife coating, gravure coating, roll coating or screen printing. It is applied, dried and formed by a method.

In this case, as the polymer binder, for example, styrene-maleic acid copolymers, homopolymers or copolymers of methacrylic resins such as polymethylmethacrylate and polyethylmethacrylate, polystyrene, acrylic-styrene copolymers are used. Coalescent, polyester resin, macron resin, ABS resin, nitrocellulose, etc. can be used.

Further, as the coloring material, for example, "Japanese Patent Publication No. 2-188290", "Japanese Patent Publication No. 3-32881",
There are cycloalkene compounds, pentadiene compounds, and the like as shown in "Japanese Patent Publication No. 4-1082". These color-forming materials may be used either individually or in combination of two or more. The main examples thereof include 1- [a-methoxy- (2-ethoxy-4-N, N) as cycloalkene compounds.
-Diethylamino) benzyl] -3- (2-ethoxy-
4-N, N-diethylaminobenzylidene) cyclohexene, 1- [a-methoxy- (2-chloro-4-N, N
-Diethylamino) benzyl] -3- (2-chloro-4
-N, N-diethylaminobenzylidene) cyclohexene, 1- [a-phenylsulfonyl- (2-chloro-
4-N, N-diethylamino) benzyl] -3- (2-
Chloro-4-N, N-diethylaminobenzylidene) sylohexene, 1- [a-methoxy- (4-biveridino)
Benzyl] -3- (4-bivelidinobenzylidene) cyclohexene, and the like. As the bentadiene compound, 1,5-bis [4- (N, N-dimethylamino)-
2-Methyl-phenyl] -5-methoxybenza-1,3
-Diene, 1,5-bis [4- (N, N-diethylamino) -2-methyl-phenyl] -5-methoxypenta-
1,3-diene, 1,5-bis [4- (N, N-di-n
-Butylamino) -2-methyl-phenyl] -5-methoxypenta-1,3-diene, 1,5-bis [4-
(N, N-Dimethylamino) -2-methyl-phenyl]
Examples include -5-ethoxypenta-1,3-diene and 1,5-bis [4- (N, N-diethylamino) -2-ethoxy-phenyl] -5-methoxypenta-1,3-diene.

Further, examples of the electron-accepting substance that reacts with these dye precursors include solid acids such as biphenol A, bisphenol S, and salicylic acid derivative zinc salt, lactic acid, acetic acid, hydrochloric acid, and the like. .

These electron-accepting substances are dissolved in oil to form microcapsules. As such oils, alkylnaphthalene, diarylalkane, alcarylated biphenyl, hydrogenated terphenyl and the like can be used.

The microcapsule wall containing the electron-accepting substance cannot be dissolved in a suitable alkylbenzene-based or ketone-based solvent that dissolves the polymer binder and the dye precursor, for example, polyurethane resin or polyurea resin. Polyamide resin, polyester resin, epoxy resin and the like can be used.

On the other hand, as the pattern printing layer 3, characters, a tint block and the like are formed by ink which absorbs light in the visible region but transmits light in the infrared region. Therefore, a white pigment that reflects light in the infrared region or a black pigment that absorbs light is not desirable, and the yellow, indigo, and red ink pigments that are the three primary colors used in normal printing are listed below. A polymer binder dispersed and made into an ink.
Organic pigments and inorganic pigments can be used.

In this case, the organic pigments include, for example, soluble azo pigments, insoluble azo pigments, phthalocyanine pigments, thioindigo pigments, anthraquinone pigments, berynone pigments, berylylene pigments, dioxazine pigments, quinacridone pigments and isoindoline pigments. Examples of the inorganic pigments include ferrocyanide, sulfide, oxide and silicate.

Examples of the polymer binder for dispersing these pigments include polyvinyl alcohol, polyvinyl chloride resin, polyvinyl acetate resin, vinyl chloride-vinyl acetate copolymer resin, saturated polyester resin, phenol resin, acrylic resin. Resins, polyurethane elastomers, etc. may be mentioned, and the pigment / resin ratio is preferably 20% or more and 50% or less.

The infrared absorbing ink thus produced was subjected to offset, screen and gravure printing methods.
It is provided on the heat-sensitive / pressure-sensitive recording layer 2 with a thickness of 1 to 10 μm on the entire surface or in a patterned form.

The heat-resistant protective layer 4 is a layer which is not deformed by the energy of the reading head of about 0.3 mJ / dot and does not change in gloss.

As the material of the heat resistant protective layer 4, for example, nitrocellulose, hydroxycellulose, carboxymethylulose, polyvinyl alcohol, styrene-maleic acid copolymer, polyester resin, ABS resin and the like can be used.

The heat-resistant protective layer 4 can be formed by dissolving or dispersing these raw materials in a solvent, coating and drying.

The material of the heat-resistant protective layer 4 is as follows.
For example, a curable resin such as a thermosetting resin, an ultraviolet curable resin, or an electron beam curable resin may be used.

A suitable thickness is about 1 to 5 μm. Further, in order to improve the slipperiness between the reading head and the heat-resistant protective layer 4 and ensure the smooth running of the read head, the heat-resistant protective layer 4 may include a lubricant such as wax. Good.

Next, a more specific example of the information recording medium of this embodiment will be described in detail.

As a specific example, the structure shown in FIG. 1 was prepared, and as a comparative example, the same structure was prepared.

(Specific Example) A heat-sensitive / pressure-sensitive recording layer 2 having the following composition was coated on a support 1 made of a milky white polyethylene terephthalate film having a thickness of 188 μm by a gravure coating method so as to have a coating thickness of 4 μm. It was formed by drying at a drying temperature of 80 degrees Celsius for about 3 minutes.

Cycloalkene compound 1- [a-methoxy- (2-ethoxy-4-N, N-diethylamino) benzyl] -3- (2-ethoxy-4-N, N-diethylaminobenzylidene) cyclohexene 4 parts Electron-accepting substance-encapsulating polyurethane microcapsules 6 parts Acrylic resin; Mitsubishi Rayon BR50 12 parts Diluting solvent; Toluene 30 parts Here, the electron-accepting substance-encapsulating polyurethane microcapsules contain both polyvalent isocyanate and polyhydroxy compound in the oil phase. Is dissolved in an aqueous solution of a protective colloid, which is emulsified and dispersed in a protective colloid aqueous solution, and further heated to cause a reaction to form a capsule wall.

That is, diisopropylnaphthalene 30
2 parts by weight of lactic acid, 5 parts by weight of an adduct of tolylene diisocyanate and trimethylolpropane, and 1 of an adduct of sorbitol and propylene oxide.
Parts and 4 parts by weight of ethyl acetate are dissolved and stirred,
2 parts by weight of carboxy-modified polyvinyl alcohol,
Add 20 parts by weight of water and add 500 parts with a homomixer.
Emulsify at 0 rpm, add 70 parts by weight of water,
When heated to 75 ° C. and held for 30 minutes, the above-mentioned electron-accepting substance-containing polyurethane microcapsules were obtained.

Next, the pattern printing layer 3 was formed on the heat-sensitive / pressure-sensitive recording layer 2 by using the following UV curable ink to a thickness of about 1 μm.
Offset printed thick.

Yellow Ink; FD OL AP Ro Yellow Ink; FD OL AP Ro Red Ink Ink; FD OL AP Ro Ind Finally, the heat-resistant protective layer 4 is formed by using the following inks from above the pattern printing layer 3. The whole surface was coated by a gravure printing method and dried at 80 ° C. for 3 minutes.

Acrylic resin: Mitsubishi Rayon BR105 10 parts Zinc stearate 0.5 part Diluting solvent: MEK / toluene = 1: 1 30 parts (Comparative Example) On a support 1 made of a milk-white polyethylene terephthalate film having a thickness of 188 μm. Then, a heat-sensitive and pressure-sensitive recording layer having the following composition was applied by a gravure coating method to a coating thickness of 4 μm and dried at a drying temperature of 80 ° C. for about 3 minutes to form a layer.

Leuco Dye S-205; manufactured by Yamada Chemical Co., Ltd. 5 parts Electron-accepting substance-encapsulating polyurethane microcapsules 15 parts Acrylic resin; Mitsubishi Rayon BR50 12 parts Diluting solvent; toluene 30 parts Furthermore, specific examples of other layers It was formed with the same composition as in the above case.

FIG. 2 is a diagram showing an example of spectral reflectance characteristics before and after recording the information recording medium manufactured by the same example, and FIG. 3 is before and after recording the information recording medium manufactured by the comparative example. 4 is a diagram showing an example of spectral reflectance characteristics of FIG.
FIG. 4 is a diagram showing an example of spectral reflectance characteristics of a pattern print layer.

From FIG. 2, it can be seen from the concrete example that the absorption of light in the visible region hardly changes, and the absorption of light in the infrared region largely changes.
The value was 0.65. When this was read by an infrared reader with almost the same reading wavelength, it could be clearly read as a signal.

On the other hand, in the comparative example, the leuco dye develops color, and the absorption of light in the visible region is large, and the appearance is black. The signal could not be read using radar.

As described above, invisible information such as characters, numbers, and bar codes which are not restricted by design can be recorded on the heat-sensitive / pressure-sensitive recording layer 2 by a thermal head, a laser beam, or writing. Further, since the recorded information can be read by a machine, it is rarely perceived by a third party, and an information recording medium having a significantly high counterfeit / tampering prevention effect can be obtained.

As described above, in the card-shaped information recording medium of this embodiment, the heat-sensitive / pressure-sensitive recording layer 2 is provided on the support 1, and the pattern is printed on the heat-sensitive / pressure-sensitive recording layer 2. The layer 3 is provided, and the heat-resistant protective layer 4 is further provided on the pattern printed layer 3.

Therefore, invisible information such as characters, numbers and bar codes which are not restricted by the design of the information recording medium is recorded on the heat-sensitive / pressure-sensitive recording layer 2 by a thermal head, a laser beam, direct writing or the like. And the information itself is invisible but machine readable.

As a result, unlike the conventional case, the effect of preventing forgery and falsification can be remarkably enhanced without being restricted by the design of the information recording medium.

The present invention is not limited to the above embodiment, but can be implemented in the same manner as described below.

(A) In the above embodiment, the heat-sensitive / pressure-sensitive recording layer 2 is provided on the support 1, the pattern printing layer 3 is provided on the heat-sensitive / pressure-sensitive recording layer 2, and the pattern printing layer 3 is provided. Although the case where the heat-resistant protective layer 4 is provided has been described above, the pattern printing layer 3 and the heat-resistant protective layer 4 may be provided as needed, and are not essential elements for the present invention.

(B) In the above embodiment, at least one of the supports 1 may be provided with a magnetic recording layer which constitutes an information recording layer together with the heat / pressure sensitive recording layer 2.

(C) In the above embodiment, the case where the present invention is applied to a card-shaped information recording medium has been described. However, the present invention is not limited to this, and information recording media of other shapes can also be used.
Similarly, the same effects can be obtained by applying the present invention.

In addition, the present invention can be variously modified and implemented within the scope of the invention.

[0060]

As described above, according to the present invention, when at least one of the supports is brought into contact with an electron-accepting substance, the absorption in the visible region hardly changes and the absorption in the infrared region is remarkable. A heat-sensitive / pressure-sensitive recording layer containing a certain dye precursor is provided, and if necessary, an ink that absorbs light in the visible region but transmits light in the infrared region is printed on the heat-sensitive / pressure-sensitive recording layer.・ Since a pattern printing layer such as a tint block is provided, and further a heat-resistant protective layer is provided on the heat-sensitive / pressure-sensitive recording layer and the pattern printing layer, invisible information such as letters, numbers and barcodes is provided. Can be recorded by a thermal head, laser beam, direct writing, etc., and the information itself is invisible, but can be read by a machine so that it can be forged and tampered with without restriction in design. Very reliable information recording medium which can be indeed prevented can be provided.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a card-shaped information recording medium according to the present invention.

FIG. 2 is a diagram showing an example of spectral reflectance characteristics before and after recording on an information recording medium manufactured according to a specific example of the example.

FIG. 3 is a diagram showing an example of spectral reflectance characteristics before and after recording the information recording medium manufactured by the comparative example in the example.

FIG. 4 is a diagram showing an example of spectral reflectance characteristics of a picture print layer in the example.

[Explanation of symbols]

1 ... Support, 2 ... Heat-sensitive / pressure-sensitive recording layer, 3 ... Pattern printing layer,
4 ... Heat-resistant protective layer.

Continuation of front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location 9121-2H B41M 5/26 Y

Claims (4)

[Claims] 1. A heat-sensitive / pressure-sensitive recording containing a dye precursor, which has a significant absorption in the infrared region with almost no change in absorption in the visible region when contacted with an electron-accepting substance, on at least one side of the support. An information recording medium comprising a layer. 2. A heat-sensitive / pressure-sensitive recording containing a dye precursor which has a remarkable absorption in the infrared region and has almost no change in absorption in the visible region when contacted with an electron-accepting substance on at least one side of the support. A layer is provided, and on the heat-sensitive / pressure-sensitive recording layer, a pattern printing layer such as characters and tint block is provided by an ink that absorbs light in the visible region but transmits light in the infrared region. Information recording medium. 3. A heat-sensitive / pressure-sensitive recording containing a dye precursor, which has a significant absorption in the infrared region and has little change in absorption in the visible region when contacted with an electron-accepting substance on at least one side of the support. A layer is provided, and on the heat-sensitive / pressure-sensitive recording layer, there is provided a picture-printing layer such as a character or a tint block with ink that absorbs light in the visible region but transmits light in the infrared region. An information recording medium comprising a heat-resistant protective layer provided on a layer and a pattern printing layer. 4. The magnetic recording layer which constitutes an information recording layer together with the heat-sensitive / pressure-sensitive recording layer is provided on at least one of the supports. The information recording medium described in.