JPH04222085A - Information recording medium - Google Patents

Abstract

PURPOSE:To form a bar code as visible information by later heating a thermal coloring layer formed on an information recording medium. CONSTITUTION:In the information recording medium for recording information on an infrared ray reflecting layer 24 by an infrared ray absorbing bar code consisting of an infrared ray absorbing material, the infrared ray absorbing bar code 18 and a dummy infrared ray transmitting bar code 20 consisting of an infrared ray transmitting material are previously formed, an infrared ray transmitting bar code 160 is additionally formed by heating the thermal coloring layer 16 and visible information is recorded by combining these bar codes.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an information recording medium,
In particular, the present invention relates to cards provided with barcodes, such as magnetic cards. 2. Description of the Related Art In information recording media such as prepaid cards, data such as denomination and remaining amount are usually recorded magnetically. Magnetic recording is widely used because it is easy to erase and rewrite, and it can record a large amount of information. However, since magnetically recorded data is easy to erase and modify, there is a high risk of it being forged. For this reason, in addition to magnetic recording, information is recorded using barcodes, and by comparing this information, the authenticity of the card is confirmed. [0003] In order to further enhance the security of the card, it is also known to use an infrared absorbing barcode as the above-mentioned barcode. In other words, for example, JP-A-2-
As described in No. 175194, an infrared reflective layer is provided on the base material surface, an infrared absorbing barcode is formed on the infrared reflective layer, and the pattern of the infrared absorbing barcode is detected by an infrared sensor to identify the denomination, etc. It identifies information. [Problems to be Solved by the Invention] However, even when using an infrared absorbing barcode pattern detected by an infrared sensor, there is a risk of forgery or unauthorized use if this pattern is read. there were. There is also the problem that additional recording or re-recording cannot be performed unlike magnetically recorded information. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide an information recording medium that effectively prevents forgery and is also re-recordable. [0006] According to the present invention, an information recording medium that records information using an infrared absorbing barcode provided on an infrared reflective layer is formed of an infrared transmitting material, and an infrared reflective layer is provided on the infrared reflective layer. It has a first infrared-transmissive barcode provided on the top together with an infrared-absorbing barcode, and a thermal coloring layer that is formed of an infrared-transmissive material and develops color when heated. A barcode is formed and visible information is recorded together with the infrared absorbing barcode and the first infrared transmitting barcode. Embodiments Next, embodiments of the information recording medium according to the present invention will be described in detail with reference to the accompanying drawings. FIGS. 1 and 2 show an embodiment in which the present invention is applied to a magnetic card. The card according to the present invention is provided with an infrared absorbing barcode 18 and a dummy barcode 20 in advance, as shown in FIG. 1, and then, as shown in FIG. It forms the Therefore, the issued card has three types of barcodes: an infrared absorbing barcode 18, a dummy barcode 20 as a first infrared transparent barcode, and a thermal coloring barcode 160 as a second infrared transparent barcode. It is formed. Although these three types of barcodes are shown with different patterns in Figures 1 and 2, they have almost the same reflectance by visible light, and when observed with the naked eye, they have the same black color. Visible as code. These barcodes are formed on the infrared reflective layer 24 (FIG. 3), as will be described later. The infrared absorbing barcode 18 is formed of an infrared absorbing material, which will be described later, and has a lower infrared reflectance than the infrared reflective layer 24, so it is detected as a barcode by an infrared sensor. The dummy barcode 20 is made of an infrared transmitting material, which will be described later, and has a high infrared reflectance that is almost the same as that of the infrared reflective layer 24. Therefore, when detected by an infrared sensor, it is detected at the same level as the infrared reflective layer 24. Ru. Similarly, thermal coloring barcode 160
has a high infrared reflectance similar to that of the dummy barcode 20, so when detected by an infrared sensor, it is detected at the same level as the infrared reflective layer 24. The structure of the card of this embodiment will be explained in more detail with reference to FIGS. 3 and 4. 3 and 4 show a cross section of a portion of the card on which a barcode is formed. As shown in FIG. 1, the card 10 includes a magnetic layer 14 on a base material 12, an infrared reflective layer 24 on the magnetic layer 14, and a thermal coloring layer 16 on the infrared reflective layer 24. An infrared absorbing barcode 18 and a dummy barcode 20 are formed on the thermal coloring layer 16, and a protective layer 22 is provided on these barcodes and the thermal coloring layer 16. The base material 12 is made of paper, plastic, or the like. For example, polyethylene terephthalate (PET), polyacetate, polystyrene (PS
), epoxy resin, polyvinyl chloride (PVC), and polycarbonate (PC) or other synthetic resin sheets or synthetic paper can be used. The thickness of the base material 12 is usually about 100 to 300 microns. The magnetic layer 14 may be one that is generally used as a magnetic recording layer in this type of magnetic recording medium, and a magnetic material that can be recorded, read, or erased by a magnetic head is used. For example, as a magnetic material, the particle size is 10 microns or less, preferably 0.01 to
5 micron Ba-ferrite, Sr-ferrite, C
o Adhesive γ-Fe2O3, γ-Fe2O3, needle iron powder, CrO2, and commonly used binder resins such as polyester resins, alkyd resins, vinyl resins, polyurethane resins, or mixed resins thereof can be used. can. [0013] The mixing ratio of the binder resin and the magnetic material is as follows:
It is appropriately set in consideration of the adhesiveness with the base material 12, the strength of the coating film, the voltage detected by the magnetic head, etc. Usually, the weight ratio of the former/latter is in the range of 1 to 1/10, preferably 1/2
~1/8 is appropriate. Note that the thickness of the magnetic layer 14 is usually about 5 to 20 microns. Alternatively, the magnetic layer 14 may be omitted by using a magnetic material for the base material 12. The infrared reflective layer 24 is provided to distinguish between a portion of the infrared reflective layer 24 where the infrared absorbing barcode 18 is present and a portion where the infrared absorbing barcode 18 is not present when detected by an infrared sensor. That is, by providing the infrared reflective layer 24, the infrared rays projected from the infrared sensor are absorbed by the infrared absorbing barcode 18 in the portion where the infrared absorbing barcode 18 is present. On the other hand, in areas where there is no infrared absorbing barcode 18, the light is reflected by the infrared reflective layer 24 and received by the sensor. This allows the infrared sensor to identify the barcode by reading the absorption waveform. The infrared reflecting layer 24 is made of a material that efficiently reflects infrared rays. Such materials include
Examples include thin films of metals such as aluminum and chromium, and white ink whose main ingredients are calcium carbonate and titanium oxide. The thermal coloring layer 16 is a layer that develops color when heated, and is a layer that transmits infrared rays. Further, the thermal coloring barcode 160 formed after coloring of the thermal coloring layer 16 also transmits infrared rays. Therefore, the thermal coloring layer 16 is made of a material that easily colors by heating and transmits infrared rays even after coloring. The thermal coloring layer 16 may contain at least a leuco dye, an acidic color developer, and a binder resin. As the leuco dye in the thermal coloring layer 16, the following examples can be used. Triphenylmethane dyes: crystal violet lactone, malachite green lactone, etc.
Fluoran dyes: 1,2-benzo-6-diethylaminofluorane, etc., auramine dyes: N-benzoyl auramine, etc., phenothiazine dyes, spiropyran dyes. As the acidic color developer in the thermal color forming layer 16, a compound having a phenolic hydroxyl group, that is, a phenolic compound can be used. Examples of such substances include phenol, o-cresol,
p-cresol, p-ethylphenol, t-butylphenol, 2,6-di-t-butyl-4-methylphenol, nonylphenol, dodecylphenol, styrenated phenol, 2,2'-methylene-bis(4-methyl- 6-t-butylphenol), α-naphthol, β
- Naphthol, hydroquinone monomethyl ether, guaiacol, eugenol, p-chlorophenol, p
-bromophenol, o-chlorophenol, o-bromophenol, 2,4,6-trichlorophenol, o
-phenylphenol, p-phenylphenol, p-
(p-chlorophenyl)phenol, o-(o-chlorophenyl)phenol, salicylic acid, ethyl p-oxybenzoate, propyl p-oxybenzoate, octyl p-oxybenzoate, dodecyl p-oxybenzoate, catechol, hydroquinone, Resorcinol, 3-methylcatechol, 3-isopropylcatechol, pt-butylcatechol, 2,5-di-t-butylhydroquinone, 4,4
'-Methylene diphenol, bisphenol A, 1,2
-Dioxynaphthalene, chlorocatechol, bromocatechol, 2,4-dihydroxybenzophenone, phenolphthalein, o-cresolphthalein, methyl protocatechuate, ethyl protocatechuate, propyl protocatechuate, protocatechuic acid octyl,
Dodecyl protocatechuate, pyrogallol, oxyhydroquinone, phloroglucin, 2,4,6-trioxymethylbenzene, 2,3,4-trioxyethylbenzene, methyl gallate, ethyl gallate, propyl gallate, butyl gallate, Examples include hexyl gallate, octyl gallate, dodecyl gallate, cetyl gallate, stearyl gallate, 2,3,5-trioxynaphthalene, tannic acid, and phenolic resin. Binder resins in the thermal coloring layer 16 include alkyd resins, vinyl chloride resins, urethane resins, xylene resins, phenol resins, coumaron resins, vinyltoluene resins, terpene resins, vinyltoluene/butadiene copolymer resins, and vinyl. Oil-soluble resins such as toluene/acrylate copolymer resins, polyvinyl alcohol resins, methyl cellulose resins, hydroxyethyl cellulose resins, carboxymethyl cellulose resins, methyl vinyl ether-maleic anhydride copolymer resins, polyacrylic acid resins, gelatin, gum arabic, etc. water-soluble resins can be used. The ratio of the leuco dye to the acidic color developer in the thermal coloring layer 16 is usually 1/0.5 to 1.
/3 (equivalent), and the ratio of the binder resin (leuco dye + acidic color developer) is usually 1/0.1 to 1.
/3 (weight). Further, the thickness of the thermal coloring layer 16 is usually about 2 to 10 microns. The material forming the infrared absorbing barcode 18 may be any material that sufficiently absorbs infrared rays, contrary to the material forming the infrared reflecting layer 24, such as organometallic complex, anthraquinone, or aluminum. , polymethine-based, diimonium-based, cyanine-based, and other infrared absorbers can be used. Preferably, for example, trade names NK2014 and NK125 manufactured by Nippon Kanko Shiki Kenkyusho, and I manufactured by Nippon Kayaku Co., Ltd.
Dissolving 1 weight percent of any one material of R-820 in a 1:1 mixture of anone and dichloromethane;
In order to match the color with the absorption bar, a solution containing 2 to 9 weight percent carbon black is prepared. Using this solution, the thermal coloring layer 1 was printed by an offset printing method.
6, print the desired bar shape on the infrared absorbing barcode 1
form 8. [0022] The dummy barcode 20 has an infrared reflective layer 2.
Similar to 4, a material that efficiently reflects infrared rays is used. The dummy barcode 20 is produced by printing the desired barcode on the thermal coloring layer 16 by using a solution obtained by removing the infrared absorbing dye from the material forming the infrared absorbing barcode 18 described above, and by the same offset printing method. It is formed by printing. The dummy barcode 20 has a reflectance similar to that of the infrared reflective layer 24 and is not detected by the infrared sensor. That is, dummy barcode 20
has the same infrared reflectance as the infrared reflective layer 24,
The part with dummy barcode 20 is dummy barcode 2
The infrared rays are reflected by the dummy barcode 20, and the infrared rays are reflected by the infrared reflective layer 24 in the areas where the dummy barcode 20 is not present, and are received by the respective sensors. Therefore, the infrared sensor cannot detect the presence or absence of the dummy barcode 20. In this way, the dummy barcode 20 is not detected by the infrared sensor and is used as part of visible information, and therefore is used as a dummy barcode. Similarly, the thermally colored barcode 160 formed by coloring the thermally colored layer 16 has the same reflectance as the infrared reflective layer 24, and is not detected by the infrared sensor, so it is used as part of visible information. is,
Used as a dummy barcode for infrared sensors. The protective layer 22 includes an infrared absorbing barcode 18,
This is a transparent layer that protects the dummy barcode 20 and the thermal coloring layer 16, and is formed to have a thickness necessary to protect them. For example, cellulose resin, urethane resin, polyester resin, alkyd resin, vinyl resin, epoxy resin, acrylic resin, etc. can be used. Oleamide, stearamide, silicone, etc. can be added to these resins to impart lubricity. Note that in order to reduce the amount of solvent used, an ultraviolet curable resin or an electron beam curable resin can be used. As the ultraviolet curable resin, for example, acrylic, epoxy, or polyester resins can be used. As described above, the card according to the present invention is provided with an infrared absorbing barcode 18 and a dummy barcode 20 in advance, as shown in FIG.
As shown in FIG. 2, a thermally colored barcode 160 is formed by coloring the thermally colored layer 16. Examples of the reflectance of these barcodes for infrared and visible light are shown in Table 1. [Table 1] Reflectance
Infrared (900
nm) Visible light (450 nm) Infrared reflective layer 32%
38% Infrared absorption barcode 8%
3% dummy barcode
30% 2%
Thermal colored barcode 31%
2% As can be seen from Table 1, the dummy barcode 20 and the thermally colored barcode 160 have a high reflectance of infrared rays like the infrared reflective layer 24, so they are not detected as barcodes by the infrared sensor. Therefore, only the infrared absorbing barcode 18 is detected as a barcode by the infrared sensor. According to such a card, information is recorded on the magnetic layer 14 and the infrared absorbing barcode 18
recorded in. Therefore, the security of the card is high because the card is identified by comparing the information read from the magnetic layer 14 by the magnetic head with the information obtained by detecting the infrared absorption barcode 18 by the infrared sensor. However, the three types of barcodes mentioned above are formed on the issued card, and these three types of barcodes have approximately the same value of reflectance to visible light as shown in Table 1. Therefore, when detected using visible light, they are visually recognized as the same barcode. therefore,
For example, when manufacturing cards, infrared absorption barcode 18
and only a dummy barcode 20 is formed, and a thermal coloring barcode 160 is additionally formed when the card is issued.
By detecting this together with the infrared absorbing barcode 18 and the dummy barcode 20 by a visible light sensor, the card can be identified. As described above, according to this card, a dummy barcode is provided for the infrared absorbing barcode 18 detected by the infrared sensor, thereby increasing the security of the card and adding the barcode as visible information. Since it is recordable, information can be recorded effectively as appropriate, and the security of the card can be further enhanced by the additionally recorded dummy barcode. [0031] According to the information recording medium of the present invention, a first infrared transmitting barcode and a second infrared transmitting barcode are formed, and a visible barcode is formed together with the infrared absorbing barcode. Therefore, the first infrared transmitting barcode and the second infrared transmitting barcode are used as dummy barcodes, and the anti-counterfeiting effect is higher than that in which only an infrared absorbing barcode is formed. moreover,
Since the second infrared-transmissive barcode can be formed later by heating, barcode information that can be detected by visible light can be additionally recorded, and the barcode can be used effectively.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment in which the present invention is applied to a magnetic card.

FIG. 2 is a plan view showing an embodiment in which the present invention is applied to a magnetic card.

FIG. 3 is a sectional view showing an embodiment in which the present invention is applied to a magnetic card.

FIG. 4 is a sectional view showing an embodiment in which the present invention is applied to a magnetic card.

[Explanation of symbols]

10 Card 12 Base material 16 Thermal coloring layer 18 Infrared absorption barcode 20 Dummy barcode 24 Infrared reflective layer 160 Thermal coloring barcode

Claims (2)

[Claims] 1. An information recording medium in which information is recorded using an infrared absorbing barcode provided on an infrared reflective layer, the information recording medium being formed of an infrared transmitting material, and having the infrared absorbing bar code provided on the infrared reflective layer. It has a first infrared transmitting barcode provided with the code, and a thermal coloring layer formed of an infrared transmitting material and colored by heating, and the second infrared transmitting barcode is formed by coloring the thermal coloring layer. An information recording medium, wherein visible information is recorded together with the infrared absorbing barcode and the first infrared transmitting barcode. 2. The information recording medium according to claim 1, further comprising a base material and a magnetic layer provided on the base material, and magnetic recording is performed on the magnetic layer. An information recording medium, wherein the infrared reflective layer and the thermal coloring layer are provided on the magnetic layer, and the infrared absorbing barcode and the first infrared transmitting barcode are provided on the thermal coloring layer. An information recording medium characterized by: