JP2002163622A - Information recording medium, reader, recording and reading method and thin film capacitor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a new and satisfactory forgery prevention technology. SOLUTION: An information recording medium 1 is provided with base materials 2 and a print pattern 3 formed on the base materials 2 while containing high dielectric materials, the print pattern 3 forms a non-printing area 5 and a printing area 4 having electrostatic capacitance higher than that of the non-printing area 5 on the base materials 2, and the print pattern 3 holds the difference of electrostatic capacitance between the printing area 4 and the non-printing area 5 as recording information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information recording medium, a reading device, a recording / reading method, and a thin film capacitor. More particularly, the present invention relates to an information recording medium provided with a countermeasure for preventing forgery and alteration, and information recorded on the medium. The present invention relates to a reading device for reading information, a recording and reading method for recording information on a medium and reading the recorded information, and a thin film capacitor that can be used for the medium.

[0002]

2. Description of the Related Art In today's highly information-oriented society, techniques for preventing forgery or falsification of information recording media such as various cards and securities, so-called "security documents", have attracted great interest. Such anti-counterfeiting technologies have traditionally included forming watermarks, holograms, kinegrams, and magnetic recording layers on or inside security documents, and special characters such as micro-character printing, color-change printing, and invisible printing. Security elements are used, such as for printing and providing security threads.

However, in recent years, personal computers, scanners, color printers, and color copiers have been improved in performance and resolution, and decryptors and input devices have been distributed in the black market. Therefore, the above-described conventional forgery / alteration prevention technology cannot always achieve the intended purpose. Further, according to the technology for preventing forgery and falsification such as hologram, kinegram, and color change printing, it is difficult to adopt machine authentication from the viewpoint of infrastructure, and it is necessary to adopt an authentication method that relies on human senses (five senses). Therefore, if the pattern, the color tone, and the color are similar between the genuine article and the imitation article, it is not easy to judge the authenticity thereof.

[0004] As a method of dealing with such a problem,
It is conceivable to employ a security system that combines a plurality of forgery / alteration prevention technologies. However, such security systems are expensive and poorly practical. Therefore, there is a demand for a novel forgery / alteration prevention technology that can sufficiently prevent forgery / alteration alone.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a novel and excellent anti-counterfeiting technique.

Another object of the present invention is to provide an information recording medium, a reading device, a recording / reading method, and a thin film capacitor capable of realizing a novel and excellent anti-counterfeiting technique.

[0007]

In order to solve the above-mentioned problems, the present invention is directed to a base material and a first material formed on the base material and made of a first material having a higher dielectric constant than the base material. Wherein the first printing pattern forms a non-printing area and a printing area having a higher capacitance than the non-printing area on the base material, the first printing pattern comprising: The pattern provides an information recording medium characterized in that a difference in capacitance between the printing area and the non-printing area is held as recording information.

The present invention also provides a method for recording information as a printing pattern on a base material, which forms a non-printing area and a printing area having different capacitances from each other, and transfers the information recorded on the base material to the non-printing area. And an information recording medium for a recording and reading method for reading by utilizing a difference in capacitance between the printed area and the base material, wherein the base material and the base material are formed on the base material and have a dielectric constant higher than that of the base material. A first printing pattern made of a high first material, wherein the first printing pattern has a non-printing area on the base material and a printing area having a higher capacitance as compared to the non-printing area. Wherein the first print pattern holds a difference in capacitance between the print area and the non-print area as recording information.

Also, the present invention provides an information recording apparatus having a structure in which a printing pattern is formed on a base material, wherein a non-printing area and a printing area having different capacitances are formed on the base material by the printing pattern. A reading device for reading information held by the printing pattern from a medium, wherein a pair of electrodes arranged in parallel with each other with a predetermined gap therebetween, and a pair of electrodes forming a resonance circuit between the pair of electrodes. And a moving mechanism for relatively moving the pair of electrodes parallel to each other while facing the information recording medium.

Further, the present invention provides an information recording apparatus having a structure in which a print pattern is formed on a base material, wherein a non-print area and a print area having different capacitances are formed on the base material by the print pattern. What is claimed is: 1. A reading device for reading information held by a print pattern from a medium, comprising: a multi-stylus electrode having three or more linear electrodes spaced apart from each other and arranged in parallel; A switching mechanism for sequentially selecting two matching linear electrodes, and a detector for forming a resonance circuit with the selected two linear electrodes and detecting a capacitance between the selected two linear electrodes. A reader is provided.

[0011] The present invention also includes a step of recording information as a printing pattern for forming a non-printing area and a printing area having different capacitances on a substrate, and the step of recording the information recorded on the substrate. A reading step utilizing a difference in capacitance between a printing area and the printing area.

Further, the present invention comprises a pair of electrodes arranged to face each other, and a dielectric layer sandwiched between the pair of electrodes, wherein the dielectric layer comprises silica and an inorganic high dielectric powder. Wherein the nitrogen concentration derived from residual Si—N bonds in the dielectric layer is 0.001 atomic% or more and 1% or less.
A thin film capacitor characterized by being in the range of at most atomic%.

Further, the present invention comprises a base material and a thin film capacitor formed on the base material, wherein the thin film capacitor is sandwiched between a pair of electrodes arranged opposite to each other and the pair of electrodes. A dielectric layer, wherein the dielectric layer contains a mixture of silica and an inorganic high dielectric powder, and a nitrogen concentration derived from residual Si—N bonds in the dielectric layer is 0.001 atomic% or more. The present invention provides an information recording medium characterized by being within the range of 1 atomic% or less.

Further, the present invention includes a base material, a thin film capacitor formed on the base material, and an output unit connected to the thin film capacitor, and is readable by using an output from the output unit. Provided is an information recording medium characterized by holding information.

The term "information recording medium" as used herein refers to a security document in which character information and image information are recorded, such as ID cards, credit cards, certificates, and securities, and for which countermeasures to prevent forgery or falsification are required. In addition to simple print media, it also includes print media used for certification of brand products, genuine parts, genuine products, and the like. Furthermore, the term “information recording medium” also includes printed matter that can impart anti-counterfeiting properties, authentication properties, and the like to the print medium, such as an adhesive seal, an adhesive sticker, and a sheet with an adhesive.

As described above, according to the present invention, information is recorded by forming a non-print area and a print area on a base material using a printing method in accordance with information to be recorded,
Reading of the recorded information is performed by detecting a difference in capacitance between the non-printing area and the printing area. According to such a technique, it is possible to realize excellent anti-counterfeiting and falsification properties as described below.

In the present invention, since the authenticity judgment is not performed only by visual inspection, the above-mentioned first print pattern may not be visually recognized. In such a case, it is difficult to realize that the information recording medium has been subjected to counterfeit alteration prevention measures.
Moreover, it is extremely easy to detect a difference in capacitance between the non-printing area and the printing area, and does not require a complicated device.

Further, in the present invention, since a printing method is used for imparting anti-counterfeiting properties, it is easy to record different information for each medium and to form a complicated pattern. Further, when the printing method is used, it is impossible to rewrite recorded information, unlike the case where a magnetic recording layer or the like is provided. That is, according to the present invention, forgery / falsification prevention properties are easily provided, but forgery / falsification is extremely difficult.

Since the first print pattern does not need to be visible, it can be white or transparent. Therefore, for example, when the first print pattern is white and the base is white, it is difficult to visually identify the first print pattern. In addition, when the first print pattern is transparent, it is difficult to identify the first print pattern visually. In particular, by forming a transparent protective layer or the like on the first print pattern, it is almost impossible to visually identify the first print pattern. Can be impossible. Also, an opaque layer can be formed on the first print pattern to make the first print pattern invisible. Further, it is also possible to make the first print pattern contain a dye, a pigment, or the like, thereby making it difficult to visually discriminate.

In the information recording medium of the present invention, the base material may be made of a dielectric or a conductor whose relative permittivity cannot be specified. For example, as the base material, various paper base materials such as securities paper, various plastic base materials used for ID cards, etc., ceramic base materials such as glass, conductor base materials such as copper, and combinations thereof, and the like. Can be used.

In the information recording medium of the present invention, the first material may be a simple substance or a mixture. The first material is not particularly limited as long as it has a higher dielectric constant than the substrate, but preferably has a relative dielectric constant of 15 or more. The volume resistivity of the first material is 1Ω · c
m or more, more preferably 10 ³ Ω · cm or more. In particular, examples of the material having a high relative dielectric constant include high dielectric materials such as inorganic high dielectric powders such as strontium titanate powder, barium titanate powder, and strontium barium titanate powder. Here, the high dielectric material is a material having a relative dielectric constant of 15 to 20 or more.

[0022] The information recording medium of the present invention may further have a second print pattern formed of a second material having a lower dielectric constant than the first material, formed on the base material. Second
May be formed so as to at least partially cover the first print pattern, or may be formed so as to be at least partially interposed between the base material and the first print pattern. It may be formed so as to be adjacent to the first print pattern on the base material.

The second material constituting the second print pattern may be a single material or a mixture.
The second material is not particularly limited as long as it has a lower relative permittivity than the first material, but the relative permittivity of the second material is 0.3 or more lower than the relative permittivity of the first material. Preferably,
More preferably, it is lower by 0.5 or more. Further, the second material may contain a magnetic material. Since most of the magnetic material is colored, when the second print pattern containing the magnetic material is formed so as to at least partially cover the first print pattern, the visibility of the first print pattern is further increased. In addition to being able to be reduced, the second pattern can be used for magnetic recording.

When the capacitance is used to prevent forgery and forgery, a more sophisticated forgery prevention technology can be realized. That is, a thin film capacitor having a structure in which the above-described dielectric layer containing a high dielectric material is sandwiched between a pair of electrodes can be formed on a substrate. In this case, by further providing an output unit connected to the thin film capacitor, an output value from the output unit can be used as information for authenticity determination or the like. Further, in this case, if a structure in which a plurality of thin film capacitors are connected to the output unit is adopted, it can be used for recording the remaining number of the prepaid card and the like. That is, when the prepaid card is used, for example, the remaining number can be recorded by destroying the number of thin film capacitors or the connection portion between the thin film capacitor and the output unit in accordance with the usage amount.

Such recording is irreversible unlike the case where a magnetic recording layer is used. Further, the above-described structure cannot be easily forged and falsified. Therefore, even with such a method, it is possible to realize excellent anti-counterfeiting properties.

In the present invention, the dielectric layer can be formed using a high dielectric composition containing a binder and an inorganic high dielectric powder. As the binder contained in the high dielectric composition, for example, polysilazane such as cyclic perhydropolysilazane is preferably used. As the inorganic high dielectric powder, it is preferable to use strontium titanate powder, barium titanate powder, strontium barium titanate powder, or the like.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in more detail with reference to the drawings. In each of the drawings, similar members are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 1 is a sectional view schematically showing an information recording medium according to the first embodiment of the present invention. The information recording medium 1 shown in FIG. 1 has a structure in which a printed pattern 3 is formed on one main surface of a base material 2. This print pattern 3
Is a thin film containing a high dielectric material obtained by printing on the base material 2 using a predetermined ink, and includes a printing region 4 having a higher relative dielectric constant and a non-printing region having a lower relative dielectric constant. A region 5 is formed. As described above, the reading of information recorded on the information recording medium 1 and the determination of the authenticity are based on the difference in the relative dielectric constant between the printing area 4 and the non-printing area 5, in other words, the difference in the capacitance. It is performed using.

Incidentally, as a recording method for preventing such forgery of the information recording medium, an optical method such as a bar code recording method, a magnetic recording method, and the like are known. However, the optical method requires a considerable film thickness to obtain a sufficient optical density. Further, in the magnetic recording method, coloring is difficult because the color of the magnetic material is brown or black, and it is necessary to excite electromagnetic induction, so that a complicated detection method is required.

Further, as a conventional technique, for example, a plastic thread, a metal thread, which cannot be detected by reflected light,
Alternatively, a method is also known in which a plastic thread whose surface is coated with a metal is woven into paper such as banknotes, and the presence or absence is detected by visual inspection using transmitted light, that is, a so-called watermark inspection. Furthermore, a method of electrically detecting the presence or absence of such a thread as a change in induced charge or capacitance by approaching the electrode rather than visually is already used (Japanese Patent Application Laid-Open No. 7-508847, JP-A-6-274
737 and Japanese Patent Publication No. 8-16942). However, in this conventional technique, a thread made of a metal or the like is sewn into paper, and it is not easy to impart anti-counterfeiting properties, and it is also difficult to form a complicated pattern. Furthermore, such threads need to have a considerable thickness, so that the above method is only applicable to limited applications.

On the other hand, in the present embodiment, the printing pattern 3 made of a material having a higher relative dielectric constant than the base material 2 is printed on the base material 2, for example, the printing pattern 3 containing a high dielectric material is used.
Is formed, and the authenticity is determined using the difference in the relative dielectric constant between the print area 4 and the non-print area 5. Therefore, according to the present embodiment, the pattern is complicated,
The information held by the print pattern 3 can be read by a simple method of bringing the medium 1 closer to the reading head, as described later, and can be made thinner and invisible. Further, in the present embodiment,
Since the authenticity is not determined by an optical method, the printed pattern 3 does not need to be visually identified and may be covered with a protective film or the like. For this reason, it is difficult to realize that the information recording medium 1 has been subjected to the counterfeiting prevention measures. Therefore, according to the present embodiment, excellent anti-counterfeiting and falsification can be realized, and it is possible to easily perform authenticity determination.

As described above, the authenticity of the information recording medium 1 is determined by reading the information held by the print pattern 3. In the present embodiment, the print pattern 3 is formed as a barcode pattern. The barcode pattern 3 will be described with reference to FIG. FIG.
Is a bar code pattern 3 of the information recording medium 1 shown in FIG.
FIG. As shown in FIG. 2, the bar code pattern 3 includes a bar portion 4a, a space portion 5, and a numeral portion 4.
b. In the barcode pattern 3, the bar portion 4a and the numeral portion 4b constitute a printing area 4, and the space portion 5 corresponds to the non-printing area 5. The current J
According to the AN code standard, a bar code pattern has one module composed of seven segments, the width of one segment is 0.3 mm, and the total number of segments is 133. In addition, one module has two pairs of white (space part) and black (bar part).

When such a bar code pattern 3 is used, since a numerical value can be recorded, it is more excellent than the case where the authenticity is determined only by the presence or absence of the print area 4 like a secret code or a thread. Thus, forgery and forgery prevention can be realized. Also, if the barcode pattern 3 is colored,
In addition to the fact that the difference in the relative permittivity between the bar portion 4a and the space portion 5 can be used to perform the authenticity judgment, the authenticity judgment can also be performed by a conventional optical method.

The thickness of the print pattern 3 is preferably 10 μm or less. With such a thickness, the medium 1
When the user touches the surface with a fingertip, the user does not feel uncomfortable, and it is difficult to realize that the print pattern 3 is formed. In addition, in the conventional barcode system, LED
In order to irradiate the bar code with light emitted from a laser or a laser oscillator and detect the reflected light (660 nm), the bar code pattern needs to be a black / white or blue / white high contrast pattern. That is, the conventional barcode pattern needs to be thick enough to optically read information. On the other hand, in the present embodiment, the barcode pattern 3 can be thinned to such an extent that the difference in capacitance between the bar portion 4a and the space portion 5 can be identified. Therefore, in consideration of security, the thickness of the print pattern 3 can be set to 0.1 μm or less, or can be colored in various colors.

Next, materials and the like used for the information recording medium 1 will be described. In the information recording medium 1, as the base material 2, for example, magnetic cards such as orange cards and telephone cards, ID cards such as licenses, employee ID cards, and student ID cards, and various cards such as IC cards, and bills And various securities such as receivables. Further, as the base material 2, a tag or the like used for authentication of a brand product, a genuine part, a genuine product, or the like can be used. Further, the base material 2 may be a base material of an adhesive seal, an adhesive sticker, and a sheet with an adhesive which can be attached to such various cards and various securities.

The material of the substrate 2 is vinyl chloride, PE
T, paper, and the like can be used. Further, as the material of the base material 2, metals and alloys such as iron, SUS, aluminum, and copper, and composite materials in which a metal or an alloy is coated with a resin such as polyurethane can be used. Furthermore, ceramics such as glass can be used as the material of the substrate 2. The substrate 2 may be flexible, such as paper or a plastic sheet, or rigid, such as a metal plate or a plastic card.

In the information recording medium 1, the bar portion 4a
Can be formed by a printing method using a composition containing a binder (binder) and a dielectric powder such as an inorganic high dielectric powder as an ink. If necessary, various additives such as a solvent, a dispersant, a thickener, and a colorant can be added to the ink.

The binder contained in the ink is selected from the viewpoints of film formability and ability to disperse the dielectric powder, and a thermoplastic resin, a thermosetting resin, a photocurable resin, or the like can be used. As such a resin, for example,
An acrylic resin or a vinyl resin can be used.

As a matter of course, this binder is used for the bar portion 4a.
Since it has an effect on the relative dielectric constant of polyacrylonitrile, such as aromatic cyanoresin commercially available from Shin-Etsu Chemical Co., Ltd. and polyacrylonitrile copolymer commercially available from Toho Rayon Co. (comonomer is methyl acrylate), etc. It is preferable that the ratio is high. Also, as a binder,
Thermoplastic resins such as polyvinyl butyral, polyurethane, and vinyl acetate copolymer, and crosslinkable resins can also be used.

When a material having a hydrophilic polar group is used as the binder, the bar portion 4a may absorb moisture and its relative permittivity, in other words, the capacitance may fluctuate. In such a case, it is preferable to protect the bar portion 4a from moisture by covering the bar portion 4a or the bar code pattern 3 with a protective film made of a vinyl chloride resin or a fluorine-based resin.

It is preferable to use polysilazane such as cyclic perhydropolysilazane as the binder. Since polysilazane, for example, cyclic perhydropolysilazane, can be fired at a relatively low temperature, even if a material having low heat resistance such as paper or a plastic sheet is used as the substrate 2, the substrate 2 may be damaged. And the bar portion 4a can be formed without the need. Further, a thin film formed using polysilazane, particularly cyclic perhydropolysilazane, has excellent abrasion resistance and chemical resistance, and obtains sufficient adhesion even when the substrate 2 is made of a metal, an alloy, or the like. be able to. In addition, polysilazanes are susceptible to hydrolysis, and therefore usually require an environment to handle them. Therefore, when polysilazane is used, high anti-counterfeiting and anti-forgery properties can be obtained from such a viewpoint. The bar portion 4a formed by using polysilazane as a binder for the dielectric powder contains a trace amount, usually 0.001 to 1 atomic% of nitrogen derived from the residual Si-N bond.

As the above-mentioned polysilazane, those commercially available from Tonensha (currently Clariant Japan) can be used. For example, cyclic perhydropolysilazane is usually commercially available as a dibutyl ether solution or a xylene solution to which an organic catalyst or a metal catalyst is added or not. In consideration of environmental issues, it is preferable to use a dibutyl ether solution, and it is preferable not to contain a catalyst from the viewpoint of ink stability.

As the dielectric powder contained in the ink, inorganic high dielectric powders such as strontium titanate powder, barium titanate powder, and strontium barium titanate powder can be used. These inorganic high dielectric powders are commercially available from Sakai Chemical Industry Co., Ltd. or the like. Among the above inorganic high dielectric powders, it is preferable to use strontium titanate powder which is a paraelectric powder. The particle size of the primary particles of the inorganic high dielectric powder is 0.1 to 0.1.
It is preferably about 5 μm. The dielectric powder may be made of any other material as long as it has a sufficient relative dielectric constant.

It is preferable to add a dispersant to the above ink in order to improve the dispersibility of the dielectric powder. As the dispersant that can be added to the ink, it is particularly preferable to use the polymer dispersant Solspers series, which is commercially available from Zeneca, but other surfactants can also be used. The amount of the dispersant added to the ink is appropriately set according to the specific surface area of the dielectric powder and the like, and is usually 0.2 to 5.0 with respect to 100 parts by weight of the dielectric powder.
It is set to about parts by weight.

Further, in order to realize an ink viscosity suitable for printing, aluminum oxide having a fine particle diameter is used as a thickener.
Powders such as titanium oxide, synthetic mica, and silica can be added within a range that does not impair the dielectric properties of the bar portion 4a.

Further, in order to color the ink, an organic or inorganic colorant such as carbon black, cyan pigment, magenta pigment, and yellow pigment may be added within a range that does not impair the dielectric properties of the bar portion 4a. it can.
The amount of the coloring agent to be added is usually 10
It is about 0.1 to 1 part by weight based on 0 part by weight.

The ink described above can be prepared using a dispersing device such as a sand mill, an attritor, a roll mill, a ball mill, a paint shaker, and a nanomizer. Among these dispersing devices, it is preferable to use, for example, a nanomizer employing an impact crushing method manufactured by Nanomizer Industries. In the case where such a nanomizer is used, it is possible to prevent the ink from being contaminated with impurities generated by abrasion of the pulverized material and lowering the relative permittivity.

The method of forming the print pattern 3 on the base material 2 using the above-mentioned ink includes letterpress printing, intaglio printing, letterpress printing, gravure printing, screen printing, offset printing, and the like. A pad printing method, a doctor blade coating method, or the like can be used. Or,
By using the above ink as a hot-melt transfer ribbon ink or an ink jet ink, the print pattern 3 can be formed by on-demand recording.

Further, as a method of forming the print pattern 3, an ink jet recording method or a thermal transfer recording method capable of on-demand printing can be employed. When the former method is adopted, the viscosity of the ink is usually set to several tens.
The thixo ratio is set to 2 or less for cps. When the latter method is adopted, the binder usually has a softening point of 13%.
A wax at about 0 to 140 ° C., preferably a polyacrylonitrile copolymer (copolymerization of methyl acrylate as required to facilitate adjustment of the softening point) or an ethylene-vinyl acetate copolymer Having a polar group having a large electron bias.

The print pattern 3 is specifically, for example,
It can be formed by the following method. First, a catalyst-free cyclic perhydropolysilazane dibutyl ether solution and a solid content of 100 parts by weight,
To 1300 parts by weight, preferably 700 to 1000 parts by weight, of a dielectric powder and 2.0 to 4.0 parts by weight of a dispersant in a nanomizer such that the total non-volatile content is 20 to 80% by weight. To prepare an ink. These mixing ratios are determined so that both the dispersibility and the high dielectric property are realized at a sufficient level. Generally, as the loading ratio of the dielectric powder increases, the film quality deteriorates and the abrasion resistance also deteriorates.

Next, the ink prepared by the above method is printed on the substrate 2 by using an appropriate printing method. Then air-dry,
The primary drying at 80 to 100 ° C., the immersion in a hydrogen peroxide solution to promote firing, and the secondary drying (firing) at 100 to 130 ° C. are sequentially performed. By completing the above steps, most of the polysilazane component is converted to silica, and a strong print pattern 3 can be obtained.

When paper is used as the base material 2, the printing area (for example, the bar portion 4a) is formed so that the longitudinal direction thereof is parallel to the paper making direction (machine direction), and the reading of a record described later is performed. Is preferably performed along a direction perpendicular to the papermaking direction of the paper. This means that the relative dielectric constant change due to the moisture absorption of the paper is inevitable, but unlike the case of free water (relative dielectric constant: 78.5), the relative dielectric constant does not increase as much as the free water does in the moisture absorption of paper (~). Water molecules are bound by the hydroxyl groups of cellulose due to hydrogen bonding, and anisotropy occurs in the relative dielectric constant of the paper. In the direction perpendicular to the orientation axis of the cellulose, the relative dielectric constant changes due to moisture absorption. Is known to be small.

The reading of information from the information recording medium 1 described above can be performed using, for example, an apparatus having a circuit configuration shown in FIG. FIG. 3 is a diagram schematically showing an example of a circuit configuration of a reading device that reads information from the information recording medium 1 shown in FIG. The reading circuit shown in FIG. 3 includes a resonance circuit 10, a sensor unit 15, an amplification circuit 20, and a detection circuit 2.
5, a differential amplifier circuit 30, a comparison circuit 35, and a variable capacitance diode 40.

The resonance circuit 10 has an oscillator 11 for generating an electromagnetic wave, a fixed coil 12, and a fixed capacitor 13. One end of the oscillator 11 is grounded, and the other end is connected to one end of the fixed coil 12. Fixed coil 12
Is connected to one end of the fixed capacitor 13,
The other end of the fixed capacitor 13 is grounded.

The sensor section 15 has a pair of electrodes arranged in parallel to each other with a certain gap therebetween, and these electrodes and the above-mentioned bar code pattern 3 constitute a kind of capacitor 16. One end of the capacitor 16 is grounded, and the other end is connected to the resonance circuit 10 between the fixed coil 12 and the fixed capacitor 13. The capacitor 16 will be described later in detail.

The amplifier circuit 20 has an amplifier 21. The amplifier 21 has one end connected to the resonance circuit 1 of the capacitor 16.
It is connected to the end connected to zero, and amplifies a voltage of a predetermined frequency that changes according to the shift of the resonance frequency, that is, an output signal.

The detection circuit 25 has a diode 26, a capacitor 27, and a resistor 28. Diode 26
Are connected to the amplifier 21 in the forward direction. One end of a capacitor 27 and one end of a resistor 28 are sequentially connected to an output terminal of the diode 26. The ends of the capacitor 27 and the resistor 28 that are not connected to the diode 26 are each grounded. This detection circuit 25
Rectifies and detects the output signal amplified by the amplifier 21.

The differential amplifier circuit 30 has a variable reference potential 31
And a differential amplifier 32. One end of the reference potential 31 is grounded, and the other end is connected to one of the input terminals of the differential amplifier 32. The other input terminal of the differential amplifier 32 is connected to the detection circuit 25. The differential amplifier circuit 30 converts the output signal from the detection circuit 25 to the reference potential 3
1 and further amplified and output.

One end of a variable capacitance diode 40 is connected to the output terminal of the differential amplifier circuit 30. The variable capacitance diode 40 has the other end connected to the resonance circuit 10 between the fixed coil 12 and the fixed capacitor 13, and reduces the environmental variability of the signal output from the differential amplifier circuit 30.

The comparison circuit 35 has a comparator 36 and a fixed reference potential 37. One end of the reference potential 37 is grounded, and the other end is connected to one of the input terminals of the comparator 36. The other input terminal of the comparator 36 is connected to the output terminal of the differential amplifier 32. The comparator 36 compares the normalized signal with a reference potential 37, binarizes the signal, and outputs the result as a rectangular wave including the signals “0” and “1”.

FIG. 4 is a sectional view schematically showing an example of a structure corresponding to the capacitor 16 of the reading circuit shown in FIG. FIG. 4 illustrates the information recording medium 1 and the read head 45. The read head 45 has a pair of linear electrodes 46 arranged parallel to each other with a certain gap therebetween, and a support 47 for supporting the linear electrodes 46. The capacitor 16 mainly includes a pair of linear electrodes 46 and the print area 4 or the non-print area 5 of the information recording medium 1. The distance between the linear electrodes 46 is equal to or less than の of the basic width of the barcode pattern 3.

For reading information recorded on the medium 1, for example, the read head 45 is moved by a moving mechanism (not shown).
This is performed by relatively translating the medium 1 in the horizontal direction in the figure. Thus, the read head 4
When the medium 5 and the medium 1 are relatively moved, a pair of linear electrodes 46 are formed.
The capacitance of the capacitor 16 changes depending on whether the printing area 4 or the non-printing area 5 exists near.
Therefore, if the circuit shown in FIG. 3 is used, the information recorded on the medium 1 can be read as a rectangular wave including the signals “0” and “1” from the change in capacitance.

In the method described above, the frequency of the oscillator 11 is preferably in the range of 10 kHz to 1 GHz. This is because if the frequency is excessively high, it becomes difficult to handle the circuit, and if the frequency is too low, the sensitivity decreases. In some cases, a fixed resistor may be provided between the oscillator 11 and the fixed coil 12. This fixed resistor preferably has a resistance value of 1 Ω to 1 kΩ.
This is because if the resistance value is excessively high, the sharpness and sensitivity of the resonance characteristics decrease, and if the resistance value is too low, tuning becomes difficult.

The fixed coil 12 preferably has an inductance of 10 μH to 10 mH. If the inductance is excessively high, a molded element cannot be obtained. If the inductance is too low, the resonance frequency will increase or the sensitivity will decrease.

The capacitance of the fixed capacitor 13 is 0.3
It is preferably in the range of pF to 300 pF. If the capacitance is excessively large, the sensitivity is reduced. If the capacitance is too small, fluctuations due to noise and stray capacitance increase.

The relative movement between the read head 45 and the medium 1 may be performed by bringing the linear electrodes 46 into contact with the surface of the medium 1 or by moving the linear electrodes 46 away from the medium 1 by a predetermined distance. May go. When the read head 45 is moved away from the medium 1 when the read head 45 is moved relative to the medium 1, the distance between the pair of linear electrodes 46 and the barcode pattern 3 is preferably 300 μm or less.
It is more preferable that it is not more than μm. In this case, sufficient sensitivity can be obtained.

The distance between the pair of linear electrodes 46 is 30 μm or less.
It is preferably about 50 μm. This is 30 μm
Is within a range of 30 μm or more that is possible when an easy method such as ordinary chemical etching is used, and is a width at which an error allowable angle (azimuth) perpendicular to a bar code is the loosest condition. Linear electrode 4 as a part
This is because no destruction occurs due to contact between the bar code pattern 6 and the bar code pattern 3, and high detection performance can be obtained. Note that this value is 1 according to the current JAN code standard.
The segment corresponds to the resolution at which a barcode having a width of 300 μm can be detected. Therefore, if the bar code is further densified in the future, the distance between the pair of linear electrodes 46 will be correspondingly reduced (for example, about 10 μm).

The speed of the relative movement between the read head 45 and the medium 1 may be a value obtained by multiplying the minimum width of the bar code pattern 3 by the operating frequency (substantially equal to the resonance frequency) or a value smaller than that. preferable.

The read head 45 can be designed using the following equations (1) and (2). (Ε-1) / (ε + 2) = Σχ _i (ε _i −1) / (ε _i +2) (1) C (F) = 8.85 × 10 ⁻¹² × εS / D (2) In the above equations (1) and (2), ε is the relative dielectric constant of the multi-component dispersion, and ε _i and χ _i are the specific relative permittivity and the volume fraction of the i component, respectively. . S indicates an electrode area (m ² ), and D indicates a distance between electrodes (m). As is apparent from the above equations (1) and (2), in order to improve the sensing performance, that is, to increase the S / N ratio, it is necessary to increase the electrode area, decrease the distance between the electrodes, or It is effective to do both of them.

In the method using the read head 45 described above, the recorded information is read by a pair of linear electrodes 46.
Are scanned in parallel along the barcode-shaped print pattern 3 to detect the resonance frequency. That is, in the method described above, it is necessary to move the reading head 45 relative to the medium 1. However, as described below, such a relative movement is not necessary if a multi-stylus electrode is used.

That is, instead of using the pair of linear electrodes 46 described above, a multi-stylus electrode having three or more linear electrodes spaced apart from each other and arranged in parallel can be used. When the multi-stylus electrode is used, if the distance between the linear electrodes is equal to or less than の of one segment width of the barcode pattern 3 and the number of the linear electrodes is larger than the total number of segments of the barcode pattern 3. For example, by sequentially selecting two adjacent linear electrodes and detecting the resonance frequency using the selected two linear electrodes as a part of the resonance circuit, the recorded information can be used for the electrodes and the medium 1. Can be read without moving. Further, even if the linear electrodes are brought into contact with the medium 1 when reading the recorded information, there is no need to move the electrodes or the medium 1, so that the bar code pattern 3 is not damaged by friction. Therefore, when the multi-stylus electrode is used, the barcode pattern 3 does not need to have high friction resistance. Therefore, the barcode pattern 3 can be formed by a hot-melt transfer recording method using a wax-based binder having a polar group as the binder.

The multi-stylus electrode can be formed by, for example, forming a conductive film on a glass epoxy substrate or a Teflon (registered trademark) substrate, and patterning the conductive film using an etching method or the like.

The reading method described with reference to FIGS. 3 and 4 can be implemented using, for example, the apparatus shown in FIG. FIG. 5 is a perspective view schematically showing the reading device according to the first embodiment of the present invention. The reading device 50 shown in FIG. 5 includes a housing 51, a display unit 52 attached to the housing 51, and various members such as a multi-stylus electrode 53 housed in the housing 51. This reading device 50
Locates the multi-stylus electrode 53 on the barcode pattern 3 of the information recording medium 1, reads information recorded on the medium 1 as a rectangular wave including signals "0" and "1", and reads the information as desired. The information is displayed on the display unit 52 having a liquid crystal display device or the like.

The reading unit 50 has a display unit 52 when not in use.
Alternatively, a lid for protecting the multi-stylus electrode 53 may be provided. In addition, the reading device 50 may be provided with an auxiliary member that facilitates alignment between the barcode pattern 3 and the multi-stylus electrode 53. Further, the reading device 50
May be provided with a mechanism for optically reading information held by the barcode pattern 3. In this case, by comparing the number read using the capacitance and the number read optically, it is determined whether it is genuine or counterfeit, and the result is displayed on the display unit 52. A mechanism for notifying by a sound such as a sound or a special sound, or a mechanism for notifying by lighting lamps may be provided.

FIG. 6 is a view showing an example of an image displayed on the display section 52 of the reading device 50 shown in FIG. FIG. 7 is a diagram illustrating another example of an image displayed on the display unit 52 of the reading device 50 illustrated in FIG. The display unit 52 of the reading device 50 may display numerical information or the like as shown in FIG. 6, or may display the result of the authenticity determination as shown in FIGS. 7 (a) and 7 (b).

A more detailed configuration of the reading device 50 shown in FIG. 5 will be described with reference to FIG. FIG. 8 is a diagram showing a circuit configuration of the reading device 50 shown in FIG. FIG.
, Reference numeral 60 denotes a multi-stylus electrode 53.
3 shows a multi-stylus electrode section having the following. The multi-stylus electrode section 60 has, for example, a structure in which a multi-stylus electrode 53 is formed on a silicon substrate.
The multi-stylus electrode section 60 is provided on the lower side of the housing 51 so as to expose the multi-stylus electrode 53.

The multi-stylus electrode section 60 is connected to an analog multiplexer 61 for sequentially selecting two adjacent linear electrodes from the linear electrodes constituting the multi-stylus electrode 53 and extracting a signal. The analog multiplexer 61 is connected to a detection circuit 62 connected to the high frequency generator 70. The detection circuit 62 is provided on, for example, a silicon substrate, and extracts a signal from the multi-stylus electrode unit 60.

The detection circuit 62 is connected to an analog / digital converter (a predetermined threshold value can be provided) 63 for binarizing the extracted signal. The analog-to-digital converter 63 includes a memory circuit 64, a signal processing circuit 65, and a decoder 66 for digitizing the multi-valued signal.
Are sequentially connected. The decoder 66 includes a display circuit 6
7 is connected, and the display unit 52 displays numerical values as shown in FIG.

In order to perform more strict authentication, when referring to a personal identification number or the like registered in a host computer or the like, the signal processing circuit 65 and the external interface 6 are referred to.
The data can be exchanged with the device 8, and the result can be sent to the authenticity judgment output circuit 69.

The reading device 5 shown in FIGS.
0 is easy to reduce the size and weight, unlike an optical barcode reader, and can be mounted on information terminal equipment such as a mobile phone. Therefore, when the print pattern 3 of the information recording medium 1 described above holds communication information, communication can be performed using such a medium 1 and an information terminal device equipped with the reading device 50.

Next, a second embodiment of the present invention will be described. FIG. 9 is a sectional view schematically showing an information recording medium according to the second embodiment of the present invention. The information recording medium 1 shown in FIG. 9 has a structure in which a barcode pattern 3 is formed on one main surface of a base material 2. The barcode pattern 3 is a thin film containing a high dielectric material obtained by printing on the base material 2 using a predetermined ink. ~
4-3 and the space portion 5 are formed as non-printing regions having a smaller relative dielectric constant.

The bar portions 4-1 to 4-3 have different thicknesses. When the thicknesses of the bar portions 4-1 to 4-3 are different as described above, their capacitances are naturally different. Therefore, the first
In the embodiment, the binarized information is recorded on the medium 1, whereas according to the second embodiment, the binarized information is recorded on the medium 1 in a ternary or larger value. Is done. In other words, according to the second aspect, information is recorded using the analog value of the capacitance.

FIG. 10 is a graph showing an example of data read from the information recording medium according to the second embodiment of the present invention. In the figure, the horizontal axis indicates position or time, and the vertical axis indicates gain. In addition, the graph of FIG. 10 is data in the case where the thickness of the bar portion is two types.

The capacitance changes according to the thickness of the bar portion.
The resonance frequency also shifts according to the thickness of the bar portion. Therefore, as shown in FIG. 10, a larger output can be obtained in the thicker bar portion than in the thinner bar portion.
Therefore, if a threshold is set between the output of the thicker bar portion and the output of the thinner bar portion, the thicker bar portion and the thinner bar portion can be distinguished. That is, a more advanced forgery / alteration prevention technology is realized. When a plurality of types of bar portions having different thicknesses are formed as described above, in the circuit shown in FIG. 3, it is necessary to multiplex the differential amplifier circuit 30 and the comparison circuit 35 according to the numbers.

As described above, when not only the position and width of the bar portion but also the thickness are used for recording information, the thickness is set to 2
It is necessary to change at more than one step. Although there is no particular upper limit set for the number of stages, usually up to about five stages are possible. Further, the thickness of the bar portion can be easily changed stepwise by using intaglio printing, pad printing, gravure printing, or the like.

Next, a third embodiment of the present invention will be described. FIG. 11 is a perspective view schematically showing an information recording medium according to the third embodiment of the present invention. The information recording medium 1 shown in FIG. 11 has a structure in which a two-dimensional pattern such as a logo mark or various secrets is formed as a printing pattern 3 on one main surface of a base material 2. This two-dimensional pattern 3
Is a thin film containing a high dielectric material obtained by printing on the base material 2 using a predetermined ink, and includes a printing region 4 having a higher relative dielectric constant and a non-printing region having a lower relative dielectric constant. Regions 5 are respectively formed.

The information held by the two-dimensional pattern 3 of the medium 1 shown in FIG. 11 is performed, for example, by scanning a read head having a pair of linear electrodes 46 in the X direction. Since the information is recorded two-dimensionally in the two-dimensional pattern 3 as described above, the reading direction is not limited to the X direction.

FIG. 12 is a graph showing the differential value of the area of the print area 4 shown in FIG. 11 at the position in the X direction. In the figure,
The horizontal axis indicates the position x in the X direction of the print area 4, and the vertical axis indicates the differential value ΔS of the area of the print area 4. The printing area 4 of the two-dimensional pattern 3 shown in FIG.
It is also discontinuous in the direction. Therefore, as shown in FIG. 12, the area of the print region 4 located immediately below the pair of linear electrodes 46 can take various values.

FIG. 13 shows the two-dimensional pattern 3 shown in FIG.
14 is a graph showing a potential detected when scanning is performed in the X direction by the read head, and FIG. 14 is a graph showing an output obtained from the data shown in FIG. In FIG. 13, the horizontal axis indicates position or time, and the vertical axis indicates potential. In FIG. 14, the horizontal axis indicates position or time, and the vertical axis indicates output.

When the area of the print area 4 located immediately below the pair of linear electrodes 46 has various values, the capacitance changes accordingly as shown in FIG. Also change. Therefore, as shown in FIG.
The thresholds a, b, c, d, and e are set, and the differential amplifier 3
When the 0 and the comparison circuit 35 are multiplexed, a multivalued output curve as shown in FIG. 14 is obtained.

As described above, in the third embodiment, the print area 4 is discontinuous not only in the X direction but also in the Y direction. That is, according to the barcode pattern described in the first embodiment, information is recorded one-dimensionally, whereas according to the present embodiment, information is formed two-dimensionally. Therefore, a more advanced forgery / alteration prevention technology is realized.

When the two-dimensional pattern 3 requires visibility, the lower limit of the resolution is set to 80 to 300 dpi.
It is preferable to set the degree. Further, as described in the second embodiment, the thickness of the print area 4 may be changed stepwise.

In the first to third embodiments described above,
Although the case where the print pattern 3 is exposed has been mainly described, the print pattern 3 may not be exposed. For example, in the case of an IC card or the like, the print pattern 3 can be reversely printed on the inner surface side of the top sheet, and the top sheet can be bonded so that the print pattern faces the card base material. Further, after forming the print pattern 3 on the card base material, it is also possible to provide a protective layer or a hiding layer on the print pattern 3.

Further, the information recording medium 1 described in the first to third embodiments is mainly cards and securities, but may be in other forms. That is, the information recording medium 1 may be a bar code label or a bar code seal using a brittle adhesive as needed, or a label or a seal printed with a secret code or a logo mark. Furthermore, the first
The techniques described in the third to third embodiments can also be used as tamper-evident measures.

In the information recording medium 1 described in the first to third embodiments, the printing area 4 containing a high dielectric material is used.
And a print area having the same color tone and a lower relative dielectric constant can be combined to further improve security. In this case, it is preferable that the printing area having the lower relative dielectric constant is substantially equal to the relative dielectric constant of the base material.

Next, a fourth embodiment of the present invention will be described. In the first to third embodiments, the formation of the print pattern 3 made of a material having a higher relative dielectric constant than the base material has been described. In a fourth embodiment described below, a first dielectric material having a higher relative dielectric constant than a base material is provided on the base material.
A first print pattern made of a material having a relative dielectric constant of
Formation of a second print pattern made of a second material lower than the material of the second print pattern will be described.

First, for the information recording medium 1 having the same structure as that described in the first to third aspects, the relationship between the type of the material forming the print pattern 3 and the capacitance of the print pattern 3 Was examined. That is, the resonance characteristics of a printed pattern 3 and a base material 2 made of a material having a relative dielectric constant ε and a volume resistivity ρ shown in Table 1 below are examined by using a reading circuit similar to that shown in FIG. Was. In addition,
The inks shown in Table 2 below were used as the materials for the printing pattern 3 (in Table 2, the process ink was Teikoku Ink Manufacturing Co., the magnetic ink was Dainichi Seika Co., and the hot-melt transfer ink ribbon was Toshiba Information Equipment Company and “Unmeasurable” means that the volume resistivity, for which relative permittivity cannot be defined, is virtually undefined because capacitance was measured with an impedance analyzer and a negative value was apparently observed. This phenomenon is typical of small ink materials.) FIG. 15 shows the result.

[0098]

[Table 1]

[0099]

[Table 2]

FIG. 15 is a graph showing resonance characteristics obtained for the information recording medium 1 according to the first to third embodiments of the present invention. In the figure, the horizontal axis indicates frequency, and the vertical axis indicates output potential. Further, in FIG.
ＦF show the resonance curves obtained for the printed pattern 3 and the substrate 2 made of the materials shown in Table 1.

As shown in FIG. 15, the print pattern 3 is composed
The volume resistivity of the material to be formed is 10¹Ω · cm or more
In this case, a clear resonance curve appears, especially when the volume resistivity is 10^Three
If it is more than Ωcm, a very clear resonance curve
Has a volume resistivity of 10 ⁰When it is less than Ω · cm
(When the printed pattern 3 is composed of a conductor), a clear resonance
No curve appears and the output potential is almost independent of frequency.
It becomes constant. From the above, the materials constituting the print pattern
Has a volume resistivity of 10⁰Ω · cm or more is preferred
10¹More preferably Ω · cm or more,
10^ThreeΩ · cm or more is most preferable.
Call

When the printed pattern 3 is made of a material having a volume resistivity of 10 ¹ Ω · cm or more, the difference between the relative permittivity of the material and the relative permittivity of the material forming the substrate 2 is zero. 0.3 or more, preferably 0.5 or more,
Since the separation between the resonance curve for the print pattern 3 and the resonance curve for the print pattern 3 is sufficient, the print pattern 3 can be detected by setting an appropriate detection frequency.

The resonance frequency of the substrate 2 did not depend on the thickness of the substrate 2 but on the relative permittivity of the substrate 2. The difference in resonance frequency between the base material 2 and the print pattern 3 did not depend on the thickness of the print pattern 3 or the like, but depended on the difference in relative dielectric constant between them.

As described above, if the material of the print pattern 3 has a sufficient volume resistivity and the relative permittivity of the constituent materials between the base material 2 and the print pattern 3 is sufficiently different, the electrostatic The print pattern 3 can be detected by measuring the capacitance. That is, in principle, any of the material forming the base material 2 and the material forming the printing pattern 3 may have a higher relative dielectric constant. However, many of the materials used for the base material 2 have low relative dielectric constants. For example, the relative permittivity of paper or plastic in a non-absorbed state is generally about 3 to
6, and the relative dielectric constant of ceramics such as glass is approximately 10 or less. Therefore, as for the degree of freedom in selecting a material, it is more advantageous to use a material having a higher relative dielectric constant than the material forming the base material 2 as the material forming the print pattern 3.

When the information recording medium 1 is actually used, the resonance curve shown in FIG. 15 may be shifted in the horizontal direction in the figure due to moisture absorption of the base material 2 or the like. for that reason,
When the detection frequency is set to the resonance point of the material constituting the base material 2 and such a shift occurs, the output potential of the base material 2 changes dramatically, and the output potential of the base material 2 and the printing pattern 3 The magnitude relationship with the output potential may be reversed from the original state. In order to prevent such reversal, for example, the detection frequency is set to the resonance point of the material forming the base material 2 as shown by the reference numeral f in FIG. It may be set slightly higher than the frequency.

Next, formation of a plurality of types of print patterns having different relative dielectric constants on a base material will be described.

FIG. 16A is a plan view schematically showing an information recording medium according to the fourth embodiment of the present invention.
16B is a cross-sectional view taken along line AA of the information recording medium shown in FIG. 16A, and FIG. 16C is a sectional view taken along line BB of the information recording medium shown in FIG. FIG.

The information recording medium 1 shown in FIGS. 16A to 16C has a structure in which a first print pattern 3 and a second print pattern 6 are formed on one main surface of a base material 2. are doing. The first print pattern 3 is the same as that described in the first to third embodiments, and includes a print area 4 having a higher relative dielectric constant and a non-print area having a lower relative dielectric constant on the base material 2. 5 are formed. The second print pattern 6 is
The first print pattern 3 is made of a material having a lower relative dielectric constant than the material of which it is made.

When the material forming the second print pattern 6 is a dielectric, any resonance curve can be obtained by measuring the above-described resonance characteristics. Therefore, the second print pattern 6
Affects the data obtained by the above-described capacitance measurement.

However, as described with reference to FIG. 15, the resonance curve of the print pattern shifts in the frequency direction according to the relative permittivity of the material forming the print pattern. Therefore, if the detection frequency is appropriately set, only the information held by the first print pattern 3 can be extracted from the data obtained by the above-described capacitance measurement.

The second print pattern 6 may form characters, images, patterns, and the like. In addition, the second print pattern 6 includes a barcode pattern shown in FIG.
1 or a simple continuous film.

The second print pattern 6 may be separated from or adjacent to the first print pattern 6, and at least a part of the second print pattern 6 may be covered by the first print pattern. . Alternatively, the second print pattern 6 is
The print pattern 3 may be partially covered or completely covered. As described above, when the second print pattern 6 at least partially covers the print pattern 3, the second print pattern 6 can function as a concealing layer that makes it difficult to view the first print pattern 3. . When both the first print pattern 3 and the second print pattern 6 are barcode patterns, the information held by the first print pattern 3 and the information held by the second print pattern 6 are compared. That is, collation of secret information becomes possible.

As the material of the second print pattern 6, for example, a dielectric having a higher relative dielectric constant than the material forming the base material 2 can be used. In this case, similarly to the first print pattern 3, the recording using the difference in the capacitance between the print area and the non-print area can be performed using the second print pattern 6.

Further, a magnetic material can be used as the material of the second print pattern 6. In this case, the second print pattern 6 can be used as a magnetic recording layer or a magnetic recording pattern. It should be noted that the above-described effect can be obtained even when a magnetic stripe formed by forming a layer containing a magnetic material on a base is attached to the base 2 instead of forming the second print pattern 6 made of a magnetic material. Can be. However, in this case, a higher forgery / falsification prevention effect cannot be obtained than when the second print pattern 6 made of a magnetic material is formed.

The second print pattern 6 can be formed by using ink generally used for printing. For example, it can be formed using a process ink as shown in Table 1 or an existing hot-melt transfer type ink. Examples of such a hot-melt transfer ink include those containing a polar wax having a structure in which a polar group such as a cyano group is introduced into a paraffin wax. These inks can contain the same various additives and solvents as described for the inks for forming the first print pattern 3.

Further, the ink used to form the second print pattern 6 can contain a high dielectric powder. As such a high dielectric powder, those described for the ink for forming the first print pattern 3 and the like can be used.

Furthermore, the second print pattern 6 can be formed using magnetic ink. Examples of such a magnetic ink include those containing a magnetic powder and a urethane-based binder, such as cobalt ferrite ink (MAG1750A) and barium ferrite ink (MAG3000A) commercially available from Dainichi Seika. Can be mentioned.

The thickness of the second print pattern 6 is not particularly limited, but the first print pattern 3 is replaced with the second print pattern 6.
In the case where the second print pattern 6 is used for magnetic recording, the thickness is preferably such that a coercive force that enables magnetic recording is achieved when the second print pattern 6 is used for magnetic recording. , For example, about 10 to 12 μm. When the second print pattern 6 is used only for displaying characters and images, the second print pattern 6 is usually formed to a thickness of about several μm.

The forgery prevention technology according to the fourth aspect described above can be more specifically applied, for example, as shown in FIG. FIG. 17 is a plan view schematically showing an example in which the forgery prevention technology according to the fourth aspect of the present invention is applied to securities. On the base material 2 of the securities 1 shown in FIG. 17, a security thread 7, a secret code 8, and a first print pattern 3 forming a barcode pattern and the like are formed. A second print pattern 6 is further formed on the base material 2, and a part of the second print pattern 6 covers the first print pattern 3. As described above, the technology according to this embodiment can be combined with the conventional forgery prevention technology.

Next, a fifth embodiment of the present invention will be described. As described above, in the information recording medium 1 according to the first to fourth embodiments, if the relative permittivity of the material forming the print pattern 3 is sufficiently higher than the relative permittivity of the base material 2,
The information held by the print pattern 3 can be read by the above-described resonance characteristic measurement. However, substrate 2
If the volume resistivity of the material forming the second print pattern 6 is less than or equal to 10 ³ Ω · cm or their relative permittivity cannot be defined, it may be difficult to read information by the above method. . In the present embodiment, a reading method particularly useful in such a case will be described.

FIGS. 18 (a) and 18 (b) respectively show a substrate 2 obtained by using a 35 μm-thick electrolytic copper foil as a conductor as the substrate 2 and forming the printed pattern 3 by an insulator.
18A and 18B are graphs showing resonance characteristics relating to the print pattern 3 and FIG. 18A shows data obtained when an electrode of the reader is brought into contact with the medium 1, and FIG. 2 shows data obtained when the medium is separated from the medium 1 or an insulator is interposed between the electrode and the medium 1. In the figure, the horizontal axis indicates frequency, and the vertical axis indicates output potential. In FIGS. 18A and 18B, reference numeral S indicates a resonance curve obtained for the base material 2, and reference numeral P indicates a resonance curve obtained for the print pattern 3.

As shown in FIG. 18A, when the electrode of the reader is brought into contact with the medium 1 when the substrate 2 is made of a conductor, the resonance curve S is constant without depending on the frequency. In addition, the output is extremely small. On the other hand, although the resonance curve P has a maximum value, the resonance curve P is largely shifted to a lower frequency side as compared with the case where the base material 2 is formed of an insulator (having a volume resistivity of 10 ³ Ω · cm or more). As a result, the output potential at the resonance point is also greatly reduced. Therefore, the difference between the output potential V _p obtained for the output voltage V _s and the printing pattern 3 obtained for the base material 2 at a predetermined detection frequency (=
V _s -V _p ) as the detection potential V _d ,
Sufficient sensitivity may not be obtained. Also, in this case,
Regardless of the value of the detection frequency, the detection potential _Vd becomes a negative value. Therefore, if the reading device used is designed for positive value as a detection voltage V _d, and thus causing inconvenience to read.

On the other hand, as shown in FIG.
When the electrode of the reader is separated from the medium 1 or an insulator is interposed between the electrode and the medium 1, the resonance curve S becomes
Compared to the case where the electrode of the reading device is brought into contact with the medium 1, the frequency shifts greatly to the high frequency side, and the output potential at the resonance point also increases significantly. Also, in this case, unlike the case where the electrode of the reader is brought into contact with the medium 1, the resonance curve P also has a clear maximum value. Therefore, in this case, a sufficiently high sensitivity can be obtained, and in addition, the detection frequency f is changed as shown in FIG.
The predetermined potential V _d by setting as shown in (b) may be a positive value. The reason why the resonance curves S and P changed in this manner was that when the electrodes of the reader were brought into contact with the medium 1, the electrodes were short-circuited and a capacitor could not be formed. This is because the electrodes of the apparatus were separated from the medium 1 or an insulator was interposed between the electrodes and the medium 1 to prevent a short circuit between the electrodes and form a capacitor.

The problem described with reference to FIG.
This can also occur when the substrate 2 is paper and absorbs water or moisture. This will be described with reference to FIG.

FIG. 19 is a graph showing the relationship between the water absorption and the relative permittivity of paper. In the figure, the horizontal axis indicates the water absorption of the paper,
The vertical axis indicates the relative dielectric constant of the paper. In the figure, the curve P
_a indicates data obtained by actually measuring,
The curve _Pc shows data obtained by converting the relative permittivity of water and the relative permittivity of paper into a volume fraction.

As shown in FIG. 19, the measured value of the relative permittivity of the water-absorbed or moisture-absorbed paper is lower than the calculated value.
This is because water, especially securities paper, contains a sizing agent, and water is free water because hydrogen bonds are formed between OH groups of cellulose as a stock and water molecules. As a result of being present as confined water rather than as. By the way, the relative dielectric constant of paper having a water absorption of about 8% (with a feeling of "sit") is about 7, and the relative dielectric constant of paper having a water absorption of about 16% (with a feeling of "good") is about 9. is there.

As shown in FIG. 19, the relative dielectric constant of the paper increases as the water absorption increases. This means that the resonance curve for the paper shifts significantly to the low frequency side in accordance with the increase in the water absorption, as is apparent from the description of FIG. Therefore, speaking extremely, if you set the detection frequency f slightly higher than the resonant frequency for the substrate 2, the output potential V _p obtained for the output potential V _s and the printing pattern 3 obtained for the base material 2 Difference (= V _s −
The sign of V _p) at a predetermined potential V _d is sometimes reversed between when high and if a low water absorption.

FIG. 1 also shows such an abnormality detection phenomenon.
The method described with reference to FIG. 8B is effective. That is, the above-described abnormality detection phenomenon can be prevented by separating the electrode of the reader from the medium 1 or by interposing an insulator between the electrode and the medium 1.

When the electrodes of the reader are separated from the medium 1 in order to prevent the above-described abnormality detection phenomenon, it is preferable that the distance between the electrodes and the medium 1 is 300 μm or less. When an insulator is interposed between the electrode and the medium 1, the thickness of the insulator is preferably 250 μm or less. When the distance between the electrode and the medium 1 and the thickness of the insulator are within the above ranges, good sensitivity can be realized.
The insulator may be formed on the surface of the electrode, or may be a protective film or the like provided on the surface of the base material.

The above-described abnormality detection phenomenon is further caused by the fact that the volume resistivity of the material forming the second print pattern 6 is approximately 10%.
^It may also occur when the resistance is ³ Ω · cm or less. Also in this case, by separating the electrode of the reading device from the medium 1 or by interposing an insulator between the electrode and the medium 1,
The above-described abnormality detection phenomenon can be prevented.

Next, the sixth and seventh embodiments of the present invention will be described. In the above-described first to fifth embodiments, formation of a print pattern containing a high dielectric material in order to improve the forgery / falsification prevention property has been described. In contrast, in the sixth and seventh embodiments described below, a capacitor having a thin film containing a high dielectric material is used in order to improve anti-counterfeiting properties.

In describing the sixth and seventh embodiments, first, matters common to them will be described.
In recent years, demand for high-capacity thin-film type capacitors has been increasing. Such a type of capacitor is considered to be used for various thin cards in addition to a lightweight circuit board mounted on a portable mobile terminal. Further, with the reduction in size and weight of the device, there is also a so-called flexible TAB substrate that can effectively utilize the remaining small space in the device.

Conventionally, various types of sintered ceramics have been used as high-capacity capacitors.
High-capacity chip capacitors of up to several μF have also been developed. This type of capacitor is manufactured in the following manner. First, ceramic powder is added to an acrylic binder, and the glass frit and various auxiliaries are dispersed together. Next, application to a conductor by a blade coating method or the like using the dispersion and formation of a green sheet are repeated to form a laminated structure. Then 1000 ~
After sintering at a high temperature of 1500 ° C. and cutting into a predetermined shape, the periphery is insulated with an epoxy resin or the like. By such a method, a chip capacitor having a size of at least about 0.6 × 0.3 × 0.3 mm is realized. However, since the ceramic layer of the capacitor manufactured by such a method is brittle, it is difficult to reduce the thickness to 10 μm or less.

A dielectric layer having a submicron thickness can be formed on a silicon wafer by a CVD method, a sputtering method, or the like (Japanese Patent Application Laid-Open No. 7-14288, Asahi Glass, etc.). However, in this method, defects such as pinholes are likely to occur, and it is impossible to increase the area. Therefore, only a capacitance of about several tens pF can be obtained at most.

Further, there is known a printed capacitor using a dielectric powder dispersed in an epoxy resin or the like. However, the thickness of this printed capacitor is several tens.
It is about μm. It is also known that an epoxy resin as a binder is changed to cyanoresin (Japanese Patent Application Laid-open No. Hei 8-
No. 125302, Hokuriku Electric Industry Co., Ltd.), but since such a resin has a polar group, sufficient moisture resistance cannot be obtained.

As described above, the conventional capacitor is thick,
There are problems such as insufficient capacitance and lack of flexibility, and it is difficult to apply the above-mentioned applications. Further, if a high temperature or vacuum process is required, the application to the above-mentioned applications is extremely limited.

On the other hand, the thin film capacitors used in the sixth and seventh embodiments of the present invention are thin, have sufficient capacitance, and have high flexibility. Therefore, application to the above-mentioned use is possible.

FIG. 20 is a sectional view schematically showing an information recording medium having thin film capacitors according to the sixth and seventh embodiments of the present invention. Information recording medium 71 shown in FIG.
Has a structure in which a capacitor 73 is formed on one main surface of a base material 72. The capacitor 73 includes a base material 72
From the side, the lower electrode 74, the dielectric layer 75, and the upper electrode 7
6 has a laminated structure in which layers are sequentially laminated. Reference numerals 77 and 78 indicate lead wire portions. The lead wire portion 77 is connected to the lower electrode 74, and the lead wire portion 78 is connected to the upper electrode 76.

[0139] The dielectric layer 75 contains a mixture of silica and an inorganic high dielectric powder. The silica constituting the dielectric layer 75 is obtained by converting polysilazane.

By the way, polysilazane commercially available from Tonen is widely used as a transparent hard coat material having a high barrier property or for forming an interlayer insulating film having a low dielectric constant. According to this polysilazane, unlike the sol-gel method, baking can be performed at a relatively low temperature and shrinkage during baking is small, so that a dense silica film can be obtained. The present inventors have found that a combination of polysilazane, particularly cyclic perhydropolysilazane, and an inorganic high dielectric powder can realize a thin film capacitor satisfying the above requirements.

As the polysilazane, it is preferable to use a cyclic perhydropolysilazane. It is preferable that the polysilazane does not contain a catalyst from the viewpoint of the dispersibility of the inorganic high dielectric powder and the storage stability of the dispersion. Furthermore, polysilazane can be used in the form of a solution. In this case, it is preferable to use dibutyl ether as a solvent rather than xylene from the viewpoint of environmental problems.

[0142] Incidentally, no matter which polysilazane is used,
A small amount of unreacted polysilazane or a reaction product containing nitrogen remains in the dielectric layer 75, though the amount is small. Therefore, in the dielectric layer 75, the nitrogen concentration derived from the residual Si—N bond is usually in the range of 0.001 to 1 atomic%.

As the inorganic high dielectric powder contained in the dielectric layer 75, the same one as described in the first to fifth embodiments can be used. That is, barium titanate, strontium titanate, strontium barium titanate, or the like can be used. Although it depends on the use of the thin film capacitor 71, it is preferable to use a paraelectric substance such as strontium titanate when it is necessary to consider stability against environmental changes.

The particle diameter of the inorganic high dielectric powder is set to 0.1 in order to have a sufficient capacitance and realize a thin dielectric layer 75.
It is preferably about 1 to 0.5 μm. An inorganic high dielectric powder having such a particle size is, for example, BT
-01 (barium titanate: particle size 0.1 μm), BT-
03 (barium titanate: particle size 0.3 μm), ST-0
1 (strontium titanate: particle size 0.1 μm) and ST-03 (strontium titanate: particle size 0.3 μm)
m).

The dispersion used for forming the dielectric layer 75 preferably contains 5 to 12 parts by weight of an inorganic high dielectric powder with respect to 1 part by weight of the polysilazane in the polysilazane solution. This is because the higher the content of the inorganic high dielectric powder, the higher the relative dielectric constant can be obtained. However, if the content is excessively high, the dielectric layer 75 such as scratch resistance and bending resistance can be obtained. This is because the characteristics required for the above are deteriorated.

A dispersant can be added to the dispersion to improve the dispersibility of the inorganic high dielectric powder.
As the dispersant that can be added to the dispersion, it is particularly preferable to use Sol Sperse series, which is a polymer dispersant commercially available from Zeneca Corporation, but other surfactants can also be used. The amount of the dispersant added to the ink is appropriately set according to the specific surface area of the inorganic high dielectric powder and the like.
It is set to about 1% by weight.

In order to enhance the suitability of the dispersion for printing and printing, a thickener such as aluminum oxide having a fine particle diameter may be used.
Powders such as titanium oxide, synthetic mica, and silica can be added as long as the dielectric properties of the dielectric layer 75 are not impaired.

Further, in order to color the dielectric layer 75, an organic or inorganic colorant such as carbon black, cyan pigment, magenta pigment, and yellow pigment can be added as long as the dielectric properties are not impaired. . The amount of the colorant to be added is usually about 0.1 to 1 part by weight based on 100 parts by weight of the nonvolatile content of the dispersion. When the dielectric layer 75 is colored in the same color as the conductive paste used for the electrodes 74 and 76 and the lead portions 77 and 78,
It becomes difficult to realize the existence of the dielectric layer 75.

The above-mentioned dispersion liquid can be prepared by using a dispersion apparatus such as a sand mill, an attritor, a roll mill, a ball mill, a paint shaker, and a nanomizer. Among these dispersing devices, it is preferable to use, for example, a nanomizer employing an impact crushing method manufactured by Nanomizer Industries. When such a nanomizer is used, it is possible to avoid that the dispersion liquid is contaminated with impurities generated by abrasion of the pulverized material, and the relative dielectric constant is reduced.

As a method for forming the dielectric layer 75 on the lower electrode 74 using the above-mentioned dispersion, a letterpress printing method,
Intaglio printing, gravure printing, screen printing, offset printing, pad printing, and the like can be used.

The dielectric layer 75 can be specifically formed, for example, by the following method. First, the above-mentioned dispersion liquid is prepared and applied and printed on the lower electrode 74. Next, the solvent is removed by performing primary drying at 70 to 80 ° C. for about 10 minutes. Then, it is immersed in a hydrogen peroxide solution for several seconds to promote the oxidation reaction,
Bake at 0-180 ° C. As described above, the dielectric layer 75 is obtained.

The capacitance of the dielectric layer 75 is proportional to its area and inversely proportional to its thickness. Therefore, in order to obtain a large capacitance, the thickness of the dielectric layer 75 is desirably smaller. However, when the thickness of the dielectric layer 75 is excessively small, the surface roughness of the dielectric layer 75 increases depending on the primary particle size of the inorganic high dielectric powder, and as a result, the surface area increases. Although the absolute value of the capacitance becomes large, the uniformity required for the dielectric layer 75 cannot be realized, and it becomes difficult to adjust the capacitance. Therefore, the thickness of the dielectric layer 75 after firing is preferably about 0.5 to 3 μm.

In the thin film capacitor 71, the base material 7
As 2, a substrate similar to the substrate 2 described in the first to third embodiments can be used. For example, the substrate 72
For example, a laminate such as glass epoxy or a Kapton film can be used. Also, when considering use in portable mobile information terminal equipment that uses high-frequency wavelengths,
From the viewpoint of low dielectric constant, low dielectric loss, and light weight, a fluororesin-based substrate can also be used.

In the thin film capacitor 71, the electrode 7
The material constituting 4,76 is not particularly limited as long as it is a conductive material that can be formed as a thin film. The electrodes 74 and 76
Is formed using a conductive paste such as a silver paste, a carbon dispersed paste layer may be interposed between the dielectric layer 75 and the electrodes 4 and 76 to prevent migration of the conductive particles. preferable.

The information recording medium 71 described above can take various forms. In a sixth embodiment described below, the information recording medium 71 is used as a wireless card.
FIG. 21 shows a wireless card 7 according to the sixth embodiment of the present invention.
FIG. The wireless card 71 shown in FIG. 21 has a structure in which an IC chip 81, a converter 82, a capacitor 73, and an antenna 83 are provided on a base material 72.

In recent years, it has been desired that a wireless card be thin, and an IC chip having a thickness of 50 μm or less and a card having a thickness of about 250 μm are commercially available.
However, a high-capacitance thin film capacitor that can be formed by coating and printing has not yet been known. Therefore, it is extremely useful to mount the above-described thin film capacitor 73 on the wireless card 71.

By the way, a magnetic card such as a prepaid card is provided with a perforated portion for the purpose of displaying the balance or the number of remaining times, but recently, the perforated portion is filled up and information in the magnetic recording layer is rewritten to be used illegally. Cases that occur frequently. For this reason, attempts have been made to detect a perforated portion by means other than optical properties (for example, see Japanese Patent Laid-Open No.
468, Tokin). In the seventh embodiment described below, the information recording medium 71 is used as a magnetic card to make it difficult to forge and falsify it.

FIG. 22 is a plan view schematically showing a magnetic card 71 according to the seventh embodiment of the present invention. The magnetic card 71 shown in FIG. 22 has a structure in which an LC circuit 85 and a magnetic recording layer (not shown) are provided on a base 72. Reference numeral 88 indicates a balance display or a remaining frequency display unit. In this magnetic card 71,
The LC circuit 85 includes the above-described capacitor 73, a coil unit 86, and an oscillator or an external terminal 87.

In this magnetic card 71, the capacitor 73 is provided with an LC circuit 85 by piercing the card 71.
Are provided so as to change the resonance frequency. Therefore, according to the magnetic card 71, even if the perforated portion is closed and the information of the magnetic recording layer is rewritten, the authenticity can be determined. This will be described in more detail with reference to FIG.

FIG. 23 is a diagram showing a part of the magnetic card 71 shown in FIG. 22 in more detail. FIG. 23A is a plan view, and FIG. 23B is a cross-sectional view along the line CC.

For example, a magnetic card 71 shown in FIG. That is, a hole larger than the width of the lead wire portion 78 is formed at the connection portion between the lead wire portion 78 and the capacitor 73 on the magnetic card 71 to insulate the lead wire portion 78 from the capacitor 73. When such a hole is formed, the insulated capacitor 73 becomes LC
Since the circuit 85 is not configured, the resonance frequency is reduced.
Therefore, if this resonance frequency is detected, it is possible to identify the remaining amount or the remaining frequency.

Further, when such a hole is formed, even if the hole is filled, the insulated capacitor 73 is formed.
Does not constitute the LC circuit 85. Even if this hole is closed with a conductive paste or the like, since the lower electrode 74 and the upper electrode 76 are short-circuited, this capacitor 73
Does not constitute the LC circuit 85. Therefore, excellent anti-counterfeit and forgery prevention properties can be realized.

In the sixth and seventh embodiments described above, the information recording medium 71 is used as a wireless card or a magnetic card, but the information recording medium 71 may be in another form. In the seventh embodiment, the LC circuit 85 shown in FIG. 22 is formed. However, other circuit configurations can be adopted.

[0164]

Example 1 A dibutyl ether solution of Solspers 28000 (35 g), a polymer dispersant manufactured by Zeneca Corporation, was prepared, and this solution was accommodated in a homogenizer container. Next, 4500 g of a cyclic perhydropolysilazane NV-120 (20 wt% dibutyl ether solution) manufactured by Tonen Co. was charged into the container, and diluted with dibutyl ether so that the total amount became 6035 g. While stirring the container with a homogenizer, strontium titanate ST-03 manufactured by Sakai Chemical Industry Co., Ltd. was gradually charged, and stirring was continued for several minutes to perform preliminary dispersion. The input amount of ST-03 is 8085
g. Next, the dispersion that had been subjected to the preliminary dispersion was applied to a Nanomizer manufactured by Nanomizer Industrial Co., Ltd. to perform the main dispersion. The thixotropic ratio of this dispersion was about 2.

[0165] The dispersion liquid having been completely dispersed as described above is applied to a glass plate having an ITO film formed on the surface thereof.
By further baking, a high dielectric film used as the above-described print pattern or dielectric layer was formed. When the dielectric properties of this high dielectric thin film were evaluated using an impedance analyzer manufactured by Hewlett-Packer Co., the relative dielectric constant was 42 and the dielectric loss was 0.2 (all at 1 MHz).
The volume resistivity measured with a ohmmeter is 10 ¹⁵ Ω · cm or more (5
0 Hz).

Further, a high dielectric film was formed on white PET by using the above dispersion liquid in the same manner as described above.
When the thickness of the high dielectric film was 20 μm or less, no crack or peeling occurred in both the bending test and the cross-cut grid test.

Example 2 A dispersion was prepared in the same manner as in Example 1, except that the amount of strontium titanate was 1200 parts by weight and the amount of dispersant was 17 parts by weight.

A high dielectric film was formed on a glass plate having an ITO film formed on its surface in the same manner as in Example 1 except that this dispersion was used, and its characteristics were examined. Except that this dispersion was used, white P was prepared in the same manner as in Example 1.
A high dielectric film was formed on the ET, and a bending test and a cross cut grid test were performed. As a result, peeling or cracking occurred in either the bending test or the cross-cut grid test. This is because polysilazane as a binder cannot sufficiently cover the strontium titanate particles. That is, the loading ratio is excessive.

Example 3 A dispersion was prepared in the same manner as in Example 1, except that the amount of strontium titanate was 400 parts by weight and the amount of dispersant was 17 parts by weight. Except that this dispersion was used, a high dielectric film was formed on a glass plate having an ITO film formed on the surface in the same manner as in Example 1, and its characteristics were examined. A high dielectric film was formed on white PET in the same manner as in Example 1 except that this dispersion was used, and a bending test and a cross cut grid test were performed. Also in this example, the thixotropic ratio was around 2, but the relative dielectric constant was 27, which was smaller than that in Example 1.

Example 4 A dispersion was prepared in the same manner as in Example 1, except that 46 g of furnace black MA-600 manufactured by Mitsubishi Chemical Corporation was charged before the strontium titanate was charged into the homogenizer container. Except that this dispersion was used, the surface was treated with IT
A high dielectric film was formed on a glass plate on which an O film had been formed, and its characteristics were examined. A high dielectric film was formed on white PET in the same manner as in Example 1 except that this dispersion was used, and a bending test and a cross cut grid test were performed. In this example, the thixotropic ratio is around 4, and the dielectric properties of the high dielectric film are a relative dielectric constant of 45 and a dielectric loss of 0.7.
(1 MHz) and the volume resistivity was 10 ¹⁵ Ω · cm or more (50 Hz). Further, no peeling or cracking occurred in the bending test and the cross cut grid test.

(Example 5) Furnace black was charged at 9
A dispersion was prepared in the same manner as in Example 4 except that the amount was 2 g. Except that this dispersion was used, a high dielectric film was formed on a glass plate having an ITO film formed on the surface in the same manner as in Example 1, and its characteristics were examined. Also, white PE was prepared in the same manner as in Example 1 except that this dispersion was used.
A high dielectric film was formed on T, and a bending test and a cross cut grid test were performed. In this example, the thixotropic ratio is around 6, and the dielectric property of the high dielectric film is 4
7. The dielectric loss was 0.8 (1 MHz) and the volume resistivity was 10 ¹⁵ Ω · cm or more (50 Hz). Further, no peeling or cracking occurred in the bending test and the cross cut grid test.

(Example 6) The amount of furnace black charged was 1
A dispersion was prepared in the same manner as in Example 4 except that the amount was 84 g. An attempt was made to form a high dielectric film by the same method as in Example 1 except that this dispersion was used, but it was difficult to form a coating film because the thixo ratio of the dispersion was excessively high.

(Example 7) Cyanoresin CR manufactured by Shin-Etsu Chemical Co., Ltd.
-S in strontium titanate ST
Example 1 in which -03 was added at a loading ratio of 6
A dispersion was prepared in the same manner as described above. Using this dispersion, a thin film was formed on a glass plate having an ITO film formed on the surface, and the characteristics were examined. Further, a thin film was formed on white PET using this dispersion, and a bending test and a cross-cut grid test were performed. As a result, the relative permittivity of the obtained thin film is as large as 70 in a normal state, and is considered to be useful as a high-dielectric film. However, cracks occur in the bending test, and the measurement environment changes, especially the humidity changes. , The relative permittivity changed greatly.

(Example 8) Butyral resin B manufactured by Sekisui Chemical Co., Ltd.
Strontium titanate S in 10% anone solution of L-2
A dispersion was prepared by dispersing T-03 to which T-03 was added at a loading ratio of 6 in the same manner as in Example 1. Using this dispersion, a thin film was formed on a glass plate having an ITO film formed on the surface, and the characteristics were examined. Further, a thin film was formed on white PET using this dispersion, and a bending test and a cross-cut grid test were performed. As a result, the relative permittivity of the obtained thin film was as small as 11, which was considered to be useful as a high dielectric film. However, a slight peeling occurred in a cross-cut grid test.

(Example 9) Hydrophobic silica powder COK84 manufactured by Nippon Aerosil Co., Ltd. was added in an amount of 0.5 to the total amount of other nonvolatile components.
A dispersion was prepared in the same manner as in Example 1 except that the dispersion was added at a ratio of% by weight. Except that this dispersion was used, a high dielectric film was formed on a glass plate having an ITO film formed on the surface in the same manner as in Example 1, and its characteristics were examined.
A high dielectric film was formed on white PET in the same manner as in Example 1 except that this dispersion was used, and a bending test and a cross cut grid test were performed. As a result, the thixotropic ratio was improved to around 5, and the same dielectric properties as in Example 1 could be obtained.

(Example 10) A barcode pattern conforming to the JAN code as shown in FIG. 2 was provided on a 500-mesh stainless steel hard calendar processed product. Next, using the dispersion prepared in Example 1, a stainless steel hard calendered product provided with the above bar code pattern was used to obtain a thickness of 180.
Screen printing was performed on a μm white PET sheet for a magnetic card. As a result, one mode has 7 characters (300
A barcode pattern of (μm width) could be formed without blurring or bleeding, and the print reproducibility was good. The thickness of the formed print pattern (barcode pattern) was 4 μm.

Example 11 Screen printing was performed in the same manner as in Example 10 except that the dispersion prepared in Example 4 was used. As a result, one mode has 7 characters (300μ
m width) can be formed without blurring or bleeding, and the print reproducibility thereof is good. The thickness of the formed print pattern (barcode pattern) was 5 μm.

(Example 12) Screen printing was performed in the same manner as in Example 10 except that the dispersion prepared in Example 5 was used. As a result, one mode has 7 characters (300μ
m width) can be formed without blurring or bleeding, and the print reproducibility thereof is good. The thickness of the formed print pattern (barcode pattern) was 6 μm.

Example 13 A reading device shown in FIG. 5 was manufactured. The frequency of the oscillator 11 is 395 kHz, the voltage is 151 mV (rms), the resistance of the fixed resistor (the internal resistance in the coil 12) is 23.5Ω, the inductance of the fixed coil 12 is 6.8 mH, and the capacitance of the fixed capacitor 13 is Was set to 13 pF.

(Example 14) Information was read from the print pattern (barcode pattern) 3 formed in Example 10 using the reading device manufactured in Example 13. The gap between the pair of electrodes 46 was 120 μm, the width of each electrode 46 was 80 μm, and the length was 8 mm. For reading information, a read head 45 is used, and a pair of electrodes 46 are used in Example 10.
The scanning was performed at 2000 mm / sec in the arrangement direction of the bar portions 4a so as to be in contact with the printed matter 1 obtained in the above. As a result, the output from the bar section 4a was 912 mV, and the output from the space section 5 was 651 mV. That is, a large output difference of 261 mV was obtained between the bar section 4a and the space section 5, and extremely high detection performance was realized.

(Example 15) Information was read from the print pattern (bar code pattern) 3 in the same manner as in Example 14 except that the pair of electrodes 46 was separated from the printed matter 1 by 30 µm. As a result, the output from the bar section 4a is 680 mV,
The output from the space section 5 was 468 mV. That is, an output difference of 212 mV was obtained between the bar portion 4a and the space portion 5, and sufficient detection performance was realized.

(Examples 16 to 48) A white PET sheet for a magnetic card having a thickness of 180 μm was used as a base material, and a thin film containing an inorganic high dielectric powder was formed on the base material (Example 1).
6-35, 40-44). A handprint paper made of Obata Paper Paper having a thickness of about 170 μm was used as a base material, and a thin film containing an inorganic high dielectric powder was formed on the base material (Example 3).
6-39, 45-48). The output of these thin films was examined while changing the parameters of the reader. The reading apparatus used was the one manufactured in Example 13, and reading was performed in the same manner as in Example 14. The results are shown in the table below.

[0183]

[Table 3]

[0184]

[Table 4]

Here, if the detected potential is 1 mV or more,
It is well known in the art that sufficient detectability can be obtained. As shown in the above table, a series of results indicate that high detectivity is obtained according to the present invention.

(Example 49) White PET print 1 according to Example 21
A commercially available process ink having the same color as that of the bar portion 4a was prepared. Using this process ink, a barcode pattern was printed on a white PET substrate. Next, the white P according to Example 21 was used.
An attempt was made to read the barcode pattern information in the same manner as described in Example 14 for the ET print 1 and the white PET print formed using a commercially available process ink. Part 5
And a large output difference was obtained. In contrast, in the latter, there is almost no output difference between the bar and the space,
It was possible to instantly determine that the bar portion did not contain the inorganic high dielectric powder.

(Example 50) Printed matter 1 of the claim paper according to Example 37
Was copied on a color copier. A comparison was made between the printed bond paper 1 according to Example 37 and the copy thereof, and no difference was observed in the color tone of the barcode pattern between them. Next, it was attempted to read the information of the barcode pattern in the same manner as described in Example 14 for the printed bond paper 1 and the copy thereof according to Example 37.
For the former, a large output difference was obtained between the bar portion 4a and the space portion 5. On the other hand, in the latter, there was almost no output difference between the bar portion and the space portion, and it was possible to instantly determine that the bar portion did not contain the inorganic high dielectric powder.

Example 51 A dibutyl ether solution of Solsperse 28000 (35 g), a polymer dispersant manufactured by Zeneca Corporation, was prepared, and the solution was placed in a homogenizer container. Next, 4500 g of a cyclic perhydropolysilazane NV-120 (20 wt% dibutyl ether solution) manufactured by Tonen Co. was charged into the container, and diluted with dibutyl ether so that the total amount became 6035 g. While stirring the container with a homogenizer, strontium titanate ST-03 manufactured by Sakai Chemical Industry Co., Ltd. was gradually charged, and stirring was continued for several minutes to perform preliminary dispersion. ST-03 input is 8
085 g. Next, the dispersion that had been subjected to the preliminary dispersion was applied to a Nanomizer manufactured by Nanomizer Industrial Co., Ltd. to perform the main dispersion. The thixotropic ratio of this dispersion was about 2.

[0189] The dispersion liquid which has been completely dispersed as described above is applied to a glass plate having an ITO film formed on the surface thereof.
By further baking, a high dielectric film used as the above-described print pattern or dielectric layer was formed. When the dielectric properties of this high dielectric thin film were evaluated using an impedance analyzer manufactured by Hewlett-Packer Co., the relative dielectric constant was 42 and the dielectric loss was 0.2 (all at 1 MHz).
The volume resistivity measured with a ohmmeter is 10 ¹⁵ Ω · cm or more (5
0 Hz).

Using the above dispersion, a white PET sheet having a thickness of 180 μm, a copper foil having a thickness of 18 μm, an aluminum foil having a thickness of 15 μm, and a Kapton film having a thickness of 125 μm were prepared in the same manner as described above. , High dielectric films were respectively formed. When the thickness of these high dielectric films was 20 μm or less, no cracks or peeling occurred in both the bending test and the cross-cut grid test.

Example 52 A dispersion was prepared in the same manner as in Example 51 except that the amount of strontium titanate used was 1200 parts by weight and the amount of dispersant was 17 parts by weight.

A high dielectric film was formed on a glass plate having an ITO film formed on the surface in the same manner as in Example 1 except that this dispersion was used, and the characteristics were examined. In addition, a white PET sheet having a thickness of 180 μm, a copper foil having a thickness of 18 μm, and a method similar to that of Example 51, except that this dispersion was used,
High dielectric films were formed on an aluminum foil having a thickness of 15 μm and a Kapton film having a thickness of 125 μm, respectively, and a bending test and a cross cut grid test were performed. as a result,
Regardless of the thickness of the high dielectric film, peeling or cracking occurred in either the bending test or the cross cut grid test. This is because polysilazane as a binder cannot sufficiently cover the strontium titanate particles. That is, the loading ratio is excessive.

Example 53 A dispersion was prepared in the same manner as in Example 1, except that the amount of strontium titanate was 400 parts by weight and the amount of dispersant was 17 parts by weight. Except that this dispersion was used, a high dielectric film was formed on a glass plate having an ITO film formed on the surface in the same manner as in Example 1, and its characteristics were examined. Also, except that this dispersion was used, a thickness of 180
μm white PET sheet, 18 μm thick copper foil, thickness 15
High dielectric films were formed on an aluminum foil having a thickness of μm and a Kapton film having a thickness of 125 μm, respectively, and a bending test and a cross cut grid test were performed. Also in this example, the thixotropic ratio was around 2, but the relative dielectric constant was 27, which was smaller than that in Example 1.

Example 54 A dispersion was prepared in the same manner as in Example 51 except that 46 g of furnace black MA-600 manufactured by Mitsubishi Chemical Corporation was charged before the strontium titanate was charged into the homogenizer container. A high-dielectric film was formed on a glass plate having an ITO film formed on the surface in the same manner as in Example 51 except that this dispersion was used, and the characteristics were examined. A 180 μm-thick white PE was prepared in the same manner as in Example 1 except that this dispersion was used.
A high dielectric film was formed on a T sheet, a copper foil having a thickness of 18 μm, an aluminum foil having a thickness of 15 μm, and a Kapton film having a thickness of 125 μm, respectively, and a bending test and a cross cut grid test were performed. In this example, the thixotropic ratio is around 4, the dielectric properties of the high dielectric film are a relative dielectric constant of 45, a dielectric loss of 0.7 (1 MHz), and a volume resistivity of 10
^{It was 15} Ω · cm or more (50 Hz). Further, no peeling or cracking occurred in the bending test and the cross cut grid test.

Example 55 A dispersion was prepared in the same manner as in Example 54 except that the amount of the furnace black was changed to 92 g. A high-dielectric film was formed on a glass plate having an ITO film formed on the surface in the same manner as in Example 51 except that this dispersion was used, and the characteristics were examined. Also,
Except that this dispersion was used, a high-dielectric substance was formed on a 180-μm-thick white PET sheet, a 18-μm-thick copper foil, a 15-μm-thick aluminum foil, and a 125-μm-thick Kapton film by the same method as in Example 1. Each of the films was formed, and a bending test and a cross cut grid test were performed. In this example, the thixotropic ratio is about 6, and the dielectric properties of the high dielectric film are a relative dielectric constant of 47 and a dielectric loss of 0.8 (1 MHz).
And the volume resistivity is 10 ¹⁵ Ω · cm or more (50 Hz)
Met. Further, no peeling or cracking occurred in the bending test and the cross cut grid test.

Example 56 A dispersion was prepared in the same manner as in Example 54 except that the amount of the furnace black was changed to 184 g. An attempt was made to form a high dielectric film by the same method as in Example 1 except that this dispersion was used.
It was difficult to form a coating film because the thixotropic ratio of the dispersion was excessively high.

(Example 57) A rectangular (2 × 2) pattern was provided on a 500-mesh screen stainless steel hard-calendered product, and the dispersion prepared in Example 55 was used to form a stainless hard calendar with a rectangular pattern. Using the screen, printing was performed on the Kapton film 72 on which circuits such as the lower electrode 74 were formed. this,
The dielectric layer 75 was formed on the lower electrode 74 by dipping in hydrogen peroxide and drying at 120 ° C. Note that the thickness of the dielectric layer 75 was about 1 μm. On this dielectric layer 75, a carbon dispersion paste was printed and dried, and then a silver paste was printed to form an upper electrode 76 and the like. As described above, the thin film capacitor 71 shown in FIG. 20 was manufactured. When the capacitance of the thin film capacitor at 125 kHz used in a wireless card was measured by an impedance analyzer, a high value of 1600 pF was obtained. It was also confirmed that the capacitance value did not change even in a high humidity atmosphere.

(Example 58) Tonen's cyclic perhydropolysilazane (20% butyl ether solution), Sakai Chemical's strontium titanate ST-03 (average particle size: 0.3
μm), butyl ether (viscosity adjusting solvent), and polymer dispersant Solspers 28000 (0.43% of the amount of strontium titanate) manufactured by Zeneca Corporation were preliminarily dispersed by a homogenizer. Next, a dielectric ink was obtained by performing the main dispersion using a Nanomizer manufactured by Nanomizer, which employs an impact pulverization method. When the weight ratio between strontium titanate and polysilazane in a dry state is 9, the relative dielectric constant of a thin film obtained by using the dielectric ink is 45.
(300 KHz). Next, the dielectric ink was printed on white PET for cards manufactured by Toray Industries, Inc., or on online passbook paper, which is securities paper of Tokushu Seiyaku Co., Ltd., to form a predetermined print pattern. The solvent is removed from the printed pattern by drying at a temperature of approximately 80 ° C., and then
The substrate was contacted with a hydrogen peroxide solution for several seconds. Furthermore, about 80 ° C ~
By performing main drying at a temperature of 120 ° C., a printed material having anti-counterfeiting properties was obtained.

(Example 59) A dielectric ink was prepared in the same manner as described in Example 58 except that polyvinyl butyral BH3 (anone solution), strontium titanate and Solspers 28000 manufactured by Sekisui Chemical Co., Ltd. were used as raw materials. Prepared. When the weight ratio between strontium titanate and solid polyvinyl alcohol is 3,
The relative permittivity of the thin film obtained using the above dielectric ink is 2
It will be about 7. According to this dielectric ink, a printed matter provided with anti-counterfeiting properties could be obtained by drying immediately after printing.

(Example 60) A printed material provided with anti-counterfeiting properties was prepared in the same manner as described in Example 59 except that CR-U, a cyanoresin manufactured by Shin-Etsu Chemical Co., was used instead of polyvinyl butyral. Created. The weight ratio of strontium titanate to solid cyanoresin was 6%.
In this case, the relative dielectric constant of the thin film obtained using the dielectric ink prepared here is about 27. Examples 58 to 6 above
Among 0, it was confirmed by a cross cut test or the like that the printed pattern formed on the printed matter of Example 58 was the hardest and had excellent sliding resistance.

The relative permittivity of the thin films obtained using the dielectric inks prepared in Examples 58 to 60 was determined by the following method. That is, first, a thin film was formed on Nesa glass (10 Ω · cm / □) obtained from Furuuchi Chemical Co., using the above dielectric ink. Next, a metal mask composed of φ2 holes was applied on the thin film, and a φ2 electrode was formed by performing gold sputtering. Next, the capacitance value between the electrodes was measured using an impedance analyzer manufactured by Hewlett-Packard Company, and the relative permittivity was calculated from the measurement result and the thickness of the thin film. The relative permittivity of the ink layer of the heat-melt transfer ink ribbon described later was determined by performing the process described below. That is, first, gold sputtering (both sides are φ
2, the other surface was the entire surface), and the relative dielectric constant was determined. Next, the relative permittivity of the hot-melt transfer ink ribbon from which the ink layer was peeled was determined in the same manner. The relative dielectric constant of the hot melt ink was calculated as the difference between these relative dielectric constants. Further, the volume resistivity of the thin film formed by using the dielectric ink and the ink layer of the hot-melt transfer ink ribbon was determined by using an insulation resistance meter.

Example 61 A reading device having the circuit configuration shown in FIG. 3 was manufactured. The frequency of the oscillator 11 is set to 395
kHz and an applied voltage of 200 mV (peak-to-pe
ak), the inductance of the fixed coil 12 is 6.8 m
H, the capacitance of the fixed capacitor 13 was set to 13 pF.
In addition, a voltage probe (1
(0.8 pF, 11.0 MΩ, output ratio 1/10).

Examples 62 to 68 Printed materials having the structures shown in Table 5 below were produced. That is, a printed material 1 in which the printed pattern 3 was formed on the base material 2 was produced. In Table 5, “first layer” indicates the print pattern 3,
“Ε” indicates a relative dielectric constant (300 KHz). "Online passbook paper" is made by Tokushu Paper, "Electrodeposited copper foil" is obtained from Fukuda Metal Foil Co., and "White PET" is obtained from Toray Co., Ltd. Is obtained from CRANE. Also,
"Ink ribbon ink black 1" was obtained from Toshiba Information Equipment Company, and "Ink ribbon ink black 2" was obtained from Alps. Further, in Table 5,
“SiTiO ₃ / PSL” means a material formed using strontium titanate and polysilazane. Further, in Table 5, the thickness of the first layer is described as “unknown” for the printed matter 1 according to Example 68 because the 100% cotton fiber paper having a rough surface was used as the base material 2. Was formed in a patchy manner.

[0204]

[Table 5]

(Examples 69 to 77) Printed materials having the structures shown in Table 6 below were prepared. That is, a printed matter 1 was formed by forming the print pattern 3 on the base material 2 and further forming the print pattern 6 so as to partially cover the print pattern 3. In Table 6, “first layer” indicates the print pattern 3
, The “second layer” indicates the print pattern 6, and “ε” indicates the relative dielectric constant (300 KHz). In Table 6, "Conk white ink", "Metallic silver ink", "Conk black ink 1", "Pearl silver ink", "Cyan ink", "Magenta ink", and "Yellow ink" are commercially available from Teikoku Ink Manufacturing Co., Ltd. "Barium ferrite ink" is MAG3000A commercially available from Dainichi Seika. In Table 6, “SiTiO ₃ / PSL” means a material formed using strontium titanate and polysilazane.

[0206]

[Table 6]

Next, using the reading device manufactured in Example 61,
The output potential at each position was examined for the printed materials according to Examples 62 to 77. For the printed materials according to Examples 63, 64, and 69 to 77, a contact measurement in which the linear electrode of the reading device was brought into contact with the printed material 1 and a non-contact measurement in which the linear electrode was separated from the printed material 250 by 250 μm were performed. The printed matter according to Example 63 was also measured when the base material was allowed to absorb water. Table 7 shows the results.

[0208]

[Table 7]

In Table 7, “base material” indicates a portion where the base material 2 of the printed matter 1 is exposed, and “base material / first layer” indicates that the first printed pattern 3 is formed on the base material 2 of the printed matter 1. The formed part is shown, and the “base material / second layer” is the second part on the base material 2 of the printed matter 1.
Shows a portion where only the print pattern 6 of “No.
The “first layer / second layer” indicates a portion where the first print pattern 3 and the second print pattern 6 are sequentially laminated on the base material 2 of the printed matter 1.

As is clear from the data shown in Table 7, in each of the printed materials 1 according to Examples 62 and 63,
The difference in output potential between the substrate 2 and the print pattern 3 is sufficiently large. That is, for any of them, the information held by the print pattern 3 can be read well. In the printed matter 1 according to Example 62, the printed pattern 3 was easily visible because the colors of the base material 2 and the printed pattern 3 were different. On the other hand, in the printed matter 1 according to Example 63, since the color of the base material 2 is pale yellow and the color of the printed pattern 3 is almost the same as white, the printed matter 1 can be visually recognized by observing the printed matter 1 from obliquely above. Although it was possible, it was extremely difficult to visually recognize the print pattern 3.

As is clear from the data relating to Example 63 in Table 7, the base material 2 made of 100% cotton fiber paper or the like was used.
Absorbs water, the difference in output potential between the base material 2 and the printed pattern 3 in contact measurement becomes small, and it becomes difficult to read information. However, in such a case, if the non-contact measurement is performed, the difference in the output potential between the base material 2 and the print pattern 3 becomes sufficiently large, and the information can be read well.

Similarly, as is clear from the data relating to Example 64 in Table 7, when the base material 2 is a conductor, the difference in the output potential between the base material 2 and the printed pattern 3 becomes smaller in the contact measurement, Reading information becomes difficult. However,
In this case, if the non-contact measurement is performed, the difference in the output potential between the base material 2 and the printing pattern 3 becomes sufficiently large, and the information can be read well.

Further, printed matter 1 according to Examples 65, 66 and 68
Then, as shown in Table 5, the difference in the relative dielectric constant between the base material 2 and the printed pattern 3 is extremely small. However, Table 7
As shown in (1), even in the printed matter 1, the difference in output potential between the base material 2 and the printed pattern 3 is large enough to read information. That is, these results show that the present method using the capacitance difference has extremely high sensitivity compared to the optical reading method.

As is clear from the data shown in Table 7, in each of the printed materials 1 according to Examples 69 and 70,
The difference in output potential between the substrate 2 and the print pattern 3 is sufficiently large. That is, for any of them, the information held by the print pattern 3 can be read well. In the printed matter 1 according to Example 69, since the film thickness of the second print pattern 6 is thin, the second print pattern 1
Can be visually recognized by observing the printed matter 1 obliquely from above. On the other hand, in the printed matter 1 according to Example 70, the portion of the first printed pattern 1 covered with the second printed pattern 2 could not be visually recognized because the thickness of the second printed pattern 6 was large. . Further, when the measurement method was changed from the contact measurement to the non-contact measurement, the output potential difference was increased, and the reading sensitivity was improved.

Further, as shown in Table 7, when the printing pattern 6 was formed using barium ferrite ink, according to the contact measurement, the portion where only the second printing pattern 6 was formed was compared with the first and second printing patterns. The output potential is equal to the portion where the print patterns 3 and 6 are sequentially laminated. On the other hand, according to the non-contact measurement, since a remarkable difference occurs between the output potentials, the information held by the portion of the print pattern 3 covered with the print pattern 6 can also be read. When the second print pattern 6 is formed using a barium ferrite ink or a cobalt ferrite ink such as MAG1700A, the ability to conceal the print pattern 3 is such that the second print pattern 6 has a thickness of about 10 μm or more. Exhibited when formed in So in this case,
The second print pattern 6 can be used as a magnetic recording layer and a concealing layer.

As is evident from the data shown in Table 7 for Examples 72 and 73, a similar trend was observed for the screen printing ink, metallic silver ink,
This was also observed when the second printing pattern 6 was formed using the ink black ink 1. The concealing ability of the print pattern 6 formed using the metallic silver ink is exhibited when the thickness is about 15 μm or more. Further, the printing pattern 6 formed using the conc black ink 1
Although the first print pattern 3 cannot be completely concealed by the thin black layer as described above, when the first print pattern 3 is a barcode pattern, the visibility is dependent on the observation angle.

In the printed matter 1 according to Examples 74 to 77, the volume resistivity of the material constituting the second printed pattern 6 is approximately 10%.
^{Although it is 3} Ω · cm or more, its relative permittivity is smaller than the relative permittivity of the material constituting the base material 2. Among these printed materials 1, in the printed materials 1 according to Examples 74 to 76, the output potential at the portion where the base material 1 is exposed is not the maximum value or the minimum value. That is, the sign of the difference between the output potential at the portion where the base material 1 is exposed and the output potential at the other portion is not either positive or negative. Therefore, the second print pattern 6
Is preferably larger than the relative dielectric constant of the material forming the substrate 2.

Next, with respect to the print pattern 3 (formed as a barcode) of the printed matter 1 according to Examples 63, 64, 69, and 74, information held by the print pattern 3 is read using an optical barcode reader. Tried. However, the information held by the print pattern 3 could not be read for any of the prints 1.

(Comparative Example 1) Using a commercially available hologram card, authenticity judgment was performed by a plurality of persons. However, it was not always easy to judge the authenticity because of the subjective effect.

(Comparative Example 2) When a regional promotion ticket having a metal strip as a security thread piece was repeatedly bent, peeling occurred at the thread portion. This is generally
This is probably due to the poor adhesion between the security thread and the substrate.

[0221]

As described above, in the present invention, a thin film containing a high dielectric powder is formed, and its capacitance is used for authenticity judgment. Such capacitance detection is extremely easy and does not require a complicated device. Further, since the thin film containing the high dielectric powder can be formed by a printing method, a complicated pattern can be formed. Further, when such a thin film is used as a dielectric layer of a thin film capacitor, a more advanced forgery prevention technology can be realized. That is, according to the present invention, an information recording medium, a reading device, a recording / reading method, and a thin-film capacitor capable of realizing a novel and excellent anti-counterfeiting technology, in other words, a novel and excellent anti-counterfeiting technology , Are provided.

[Brief description of the drawings]

FIG. 1 is a sectional view schematically showing an information recording medium according to a first embodiment of the present invention.

FIG. 2 is a plan view showing a barcode pattern of the information recording medium shown in FIG.

FIG. 3 is a diagram schematically illustrating an example of a circuit configuration of a reading device that reads information from the information recording medium illustrated in FIG. 1;

FIG. 4 is a sectional view schematically showing an example of a structure corresponding to a capacitor of the reading circuit shown in FIG. 3;

FIG. 5 is a perspective view schematically showing the reading device according to the first embodiment of the present invention.

FIG. 6 is a view showing an example of an image displayed on a display unit of the reading device shown in FIG. 5;

7A and 7B are diagrams illustrating another example of an image displayed on the display unit of the reading device illustrated in FIG. 5;

8 is a diagram showing a circuit configuration of the reading device shown in FIG.

FIG. 9 is a sectional view schematically showing an information recording medium according to a second embodiment of the present invention.

FIG. 10 is a graph showing an example of data read from an information recording medium according to the second embodiment of the present invention.

FIG. 11 is a perspective view schematically showing an information recording medium according to a third embodiment of the present invention.

12 is a graph showing a differential value of the area of the print region shown in FIG. 11 at a position in the X direction.

FIG. 13 is a graph showing a potential detected when the two-dimensional pattern shown in FIG. 11 is scanned in the X direction by a reading head.

FIG. 14 is a graph showing an output obtained from the data shown in FIG.

FIG. 15 is a graph showing resonance characteristics obtained for the information recording media according to the first to third embodiments of the present invention.

16A is a plan view schematically showing an information recording medium according to a fourth embodiment of the present invention, and FIG. 16B is a cross section of the information recording medium shown in FIG. FIG. 3C is a cross-sectional view of the information recording medium shown in FIG.

FIG. 17 is a plan view schematically showing an example in which the forgery prevention technology according to the fourth embodiment of the present invention is applied to securities.

18A and 18B are graphs respectively showing resonance characteristics obtained when a conductor is used as a base material and a printed pattern is formed of an insulator.

FIG. 19 is a graph showing the relationship between the water absorption and the relative permittivity of paper.

FIG. 20 is a sectional view schematically showing an information recording medium having thin film capacitors according to sixth and seventh embodiments of the present invention.

FIG. 21 is a plan view schematically showing a wireless card according to a sixth embodiment of the present invention.

FIG. 22 is a magnetic card 7 according to the seventh embodiment of the present invention.
FIG.

23A is a diagram showing a part of the magnetic card 71 shown in FIG. 22 in more detail, and FIG. 23B is a cross-sectional view taken along line CC of FIG.

[Explanation of symbols]

1,71: information recording medium; 2,72: base material; 3,6
... print pattern; 4, 4a, 4b, 4-1 to 4-3 ... print area; 5 ... non-print area; 7 ... security thread;
8 secret character; 10 resonance circuit; 11 oscillator;
Coil; 13, 16, 27, 73 ... condenser; 15
... Sensor part; 20 ... Amplifier circuit; 21 ... Amplifier;
5: detection circuit; 26: diode; 28: resistor;
0: Differential amplifier circuit; 31: Reference potential; 32: Differential amplifier; 35: Comparison circuit; 36: Comparator;
Reference potential: 40: variable capacitance diode; 45: read head; 46: linear electrode; 47: support; 50: reader; 51: housing; 52: display unit; Electrode part; 6
1: Analog multiplexer; 62: Detection circuit;
... analog-to-digital converter; 64 ... memory circuit;
65 ... signal processing circuit; 66 ... decoder; 67 ... display circuit; 68 ... external interface; 69 ... authenticity judgment output circuit; 70 ... high frequency generator; 74 ... lower electrode;
75: dielectric layer; 76: upper electrode; 77, 78: lead wire portion; 81: IC chip; 82: converter;
83 antenna; 85 LC circuit; 86 coil part;
87 ... oscillator or external terminal; 90 ... position;

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) // G07D 7/02 G06K 19/00 H 7/04 H01G 4/06 102 (72) Inventor Tomoichi Domon Kawasaki, Kanagawa No. 1, Komukai Toshiba-cho, Ichiko-ku, Toshiba R & D Center (72) Inventor Teruo Murakami No. 1, Komukai Toshiba-cho, Kochi-ku, Kawasaki, Kanagawa Pref. Hideyuki 1 Tokoba, Komukai Toshiba-cho, Kawasaki-shi, Kanagawa Prefecture F-term in Toshiba R & D Center (reference) 2C005 HA02 HB03 HB07 HB10 JA01 JA15 JB28 MB02 NA09 TA22 3E041 AA03 BA09 BB07 BB08 5B035 AA13 BA03 BB09 CA01 AB01 FF05 FG03

Claims (12)

[Claims] A first printed pattern formed on the base material and made of a first material having a higher dielectric constant than the base material, wherein the first printed pattern is Forming a non-printing area and a printing area having a higher capacitance as compared to the non-printing area on the substrate, wherein the first printing pattern has an electrostatic capacitance between the printing area and the non-printing area. An information recording medium characterized by holding a difference in capacity as recording information. 2. The method according to claim 1, wherein the first material contains a mixture of silica and an inorganic high dielectric powder, and a nitrogen concentration derived from residual Si—N bonds in the first print pattern is 0.001 atomic% or more. 2. The information recording medium according to claim 1, wherein the content is within a range of 1 atomic% or less. 3. The information recording medium according to claim 1, wherein the relative permittivity of the first material is 15 or more. 4. A second print pattern made of a second material having a lower dielectric constant than the first material, the second print pattern being formed on the base material so as to cover at least a part of the first print pattern. The information recording medium according to claim 1, further comprising: 5. The volume resistivity of the first material is 1Ω · c.
5. The information recording medium according to claim 4, wherein the relative permittivity of the first material is 0.3 or more, and the relative permittivity of the first material is 0.3 or more higher than the relative permittivity of the second material. 6. The information recording medium according to claim 4, wherein the second print pattern contains a magnetic material. 7. Printing from an information recording medium having a structure in which a print pattern is formed on a base material and having a non-print area and a print area having different capacitances formed on the base material by the print pattern. What is claimed is: 1. A reading device for reading information held by a pattern, comprising: a pair of electrodes arranged in parallel with each other with a predetermined gap therebetween; and a capacitance between the pair of electrodes by forming a resonance circuit with the pair of electrodes. And a moving mechanism for relatively moving the pair of electrodes parallel to each other while facing the information recording medium. 8. Printing from an information recording medium having a structure in which a print pattern is formed on a base material and having a non-print area and a print area having different capacitances formed on the base material by the print pattern. A reading device for reading information held by a pattern, comprising: a multi-stylus electrode having three or more linear electrodes spaced apart from each other and arranged in parallel; and two adjacent stylus electrodes of the three or more linear electrodes. A switching mechanism for sequentially selecting, and a detector for forming a resonance circuit with the selected two linear electrodes and detecting a capacitance between the selected two linear electrodes. Reader. 9. A step of recording information as a print pattern that forms a non-print area and a print area having different capacitances on a base material, and the information recorded on the base material is stored in the non-print area and the print area. A step of reading using a difference in capacitance between the print area and the printing area. 10. A semiconductor device comprising: a pair of electrodes disposed to face each other; and a dielectric layer sandwiched between the pair of electrodes, wherein the dielectric layer contains a mixture of silica and an inorganic high dielectric powder. And a nitrogen concentration derived from residual Si-N bonds in the dielectric layer is not less than 0.001 atomic% and not more than 1 atomic%. 11. A thin film capacitor comprising: a base material; and a thin film capacitor formed on the base material, wherein the thin film capacitor includes a pair of electrodes arranged to face each other, and a dielectric layer sandwiched between the pair of electrodes. Wherein the dielectric layer contains a mixture of silica and an inorganic high dielectric powder, and the residual Si-
An information recording medium, wherein the concentration of nitrogen derived from N bonds is 0.001 atomic% or more and 1 atomic% or less. 12. Information is recorded as a print pattern on a base material that forms a non-print area and a print area having different capacitances from each other, and the information recorded on the base material is stored in the non-print area and the print area. An information recording medium for a recording / reading method for reading by utilizing a difference in capacitance between a base material and a first base material formed on the base material and having a higher dielectric constant than the base material. A first printing pattern made of a material, wherein the first printing pattern forms a non-printing area and a printing area having higher capacitance as compared to the non-printing area on the base material, The information recording medium according to claim 1, wherein the first print pattern holds a difference in capacitance between the print area and the non-print area as recording information.