JP2002103796A - Ink jet information recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet information recording medium having a forgery and a falsification preventing function. SOLUTION: The ink jet information recording medium comprises a magnetic recording layer formed on one side surface of an ink jet recording layer of a support, a concealing layer provided on the magnetic recording layer to invisibly conceal the magnetic recording layer, and an ink jet recording layer further provided on the concealing layer. In this medium, particularly as the concealing layer, a pearl pigment is contained. Thus, a thickness of the concealing layer can be reduced to 5 μm or less as compared with another coloring pigment, and hence the information recording medium having good recording characteristics of the magnetic recording layer can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink-jet information recording medium, and more particularly, to a forgery or tampering by having a magnetic recording function and an ink-jet information recording function, and by invisiblely concealing a magnetic recording layer. The present invention relates to an ink jet information recording medium having an excellent prevention function.

[0002]

2. Description of the Related Art In recent years, an ink jet recording system for printing by an ink jet system in a wide range of fields such as printers and recorders of various measuring instruments, printers for labels, printers for POS, and vending machines such as tickets and admission tickets. Is being used.
The ink jet recording method is conveniently used in business offices, retail stores, and homes because both monochrome and color recording are possible. However, the recording in the ink jet recording method can easily perform the same printing due to the development of personal computers, printers, printing fonts, etc., and the use thereof is used for tickets, admission tickets, stamps, stamps, bills, checks, certificates, etc. There was a problem that it was easy to falsify and falsify when expanding to "gold vouchers". For the purpose of preventing forgery, the so-called "gold voucher" recording paper is printed with a forgery-preventing tint block,
Although forgery-prevention printing has been performed using micro-characters, the development of color copying in recent years has made it difficult for amateurs to make copies easily.

On the other hand, in recent years, due to the rapid spread of telephone cards and orange cards (registered trademark), prepaid cards have been attracting a quick notice, and have been widely used in transportation,
Practical application in the field of various distribution service industries is rapidly spreading. The spread of such a magnetic recording card is due to the fact that the information storage capacity of the magnetic recording layer is large, the reading of the written information is simple and accurate, and it can be easily processed by an automatic ticket gate or a vending machine. And the fact that fractional amount processing is possible and effective for labor saving.

[0004] As a prepaid card balance display method,
Conventionally, various methods such as a punch hole method, an electrophotographic method, an electrostatic recording method, a printing method using ink, a diazo copying method, and a thermal recording method have been adopted. The punch hole method has the drawbacks that since the exact balance cannot be grasped only by the card, the usage history is not clear, and punch waste accumulates in the reader / writer. In addition, any recording method other than the thermal recording method requires development and fixing steps, and has problems such as an increase in the size of the printing apparatus and cost. On the other hand, since the thermal recording method does not require these steps, the apparatus can be downsized,
Although labor saving is possible, there are problems such as storage stability and poor printing due to sticking phenomenon of the thermal head.

In order to solve such a problem, for example, Japanese Patent Application Laid-Open
JP-A-257022 proposes an ink jet magnetic composite recording sheet in which a magnetic recording layer and an ink jet recording layer are laminated on a support.

[0006] However, although an ink jet recording layer is provided on the magnetic recording layer, the ink jet recording layer itself cannot generally invisibly cover a magnetic recording layer having a dark color of black to black brown, and particularly has a low ink absorbing property. If the coating layer structure of the ink jet recording layer is made porous to secure it, the result is that the magnetic recording layer still lacks concealing properties.
Not only the ink jet recording layer, but also the magnetic recording layer, if its existence is known, forgery is possible if magnetic recording paper with exactly the same magnetic characteristics is made. As you can see from the amount of forgery. Therefore, by recording information corresponding to ink jet recording on the magnetic recording layer by concealing the magnetic recording layer so that the presence of the concealing layer is not detected, it is possible to prevent forgery and tampering. However, there is a problem that the recording / reproducing function of the magnetic recording layer is deteriorated.

In general, as the concealing pigment, for example, it is known that an organic pigment constituting a process ink (yellow, magenta, cyan) is mixed at an appropriate ratio.
Phthalocyanine, thioindigo, anthraquinone, berynone, berylen, dioxazine, quinacridone, isoindoline and the like are well known. Further, as a white organic pigment, a pigment containing a copolymer such as a styrene resin, a melamine resin, an acrylic resin, and a urea resin is known.

The inorganic pigments include, for example, carbonates, oxides, hydroxides, sulfates such as aluminum, zinc, magnesium, barium, calcium, and titanium, and natural and synthetic silicas, clays, zeolites, kaolins, calcined kaolins Inorganic white pigments and the like containing clays are well known.

However, using such organic or inorganic pigments to cover a magnetic recording layer generally having a dark color of black to black-brown requires a large amount of pigment, thereby deteriorating the recording / reproducing characteristics of the magnetic recording layer. There was a problem of doing so.

[0010]

The present invention relates to an ink jet information recording medium, and more particularly to a magnetic recording medium having a magnetic recording / reproducing function and an ink jet information recording function. The present invention relates to an ink-jet information recording medium having a function of preventing forgery and falsification by maintaining a high recording / reproducing function of a recording layer.

[0011]

Means for Solving the Problems In view of such circumstances, the present inventor has made intensive studies to achieve the above object, and as a result, formed a magnetic recording layer on one side of a support, and provided an ink jet recording layer thereon. In the meantime, it has been found that an ink-jet information recording medium having a function of preventing forgery and tampering can be obtained by providing a concealing layer for concealing the magnetic recording layer invisibly, thereby completing the present invention. In particular, the concealing layer contains pearl pigment particles that are colored by light interference,
This is preferable because concealment is possible with a thin layer and the recording function of the magnetic recording layer can be maintained at a high level.

That is, even if the ink jet recording layer is tampered with, it is possible to detect tampering by comparing it with the recording information of the magnetic recording layer, and it is difficult to detect the presence of the magnetic recording layer by using the concealment layer. And can further contribute to preventing forgery and tampering.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION When the concealing layer of the present invention contains pearl pigment particles which develop color by light interference, the pearl pigment is concealed in comparison with other general inorganic or organic pigments in order to utilize interference colors. Even if the thickness of the layer is reduced to 5 μm or less, the magnetic recording layer having a deep color can be completely concealed, so that an information recording medium having good recording and reproducing characteristics of the magnetic recording layer can be obtained.

Further, the ink jet information recording medium of the present invention is capable of ink jet recording with a prepaid card or the like and, at the same time, is provided with an ink jet recording layer via a concealing layer on the upper surface of the magnetic recording layer. The layer does not appear on the surface and is very good as an information recording medium such as a card.

The support of the present invention may be a neutral or acidic high-quality paper mainly composed of ordinary natural pulp, a high-quality paper, a recycled paper, an art paper, a laminated paper or a translucent trace paper. Synthetic papers and the like manufactured to such a type can be used.

As the thermoplastic resin of the synthetic paper support, polyolefin resins such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-
The main component is a vinyl acetate copolymer, but a mixture of a thermoplastic resin such as polystyrene and an acrylate copolymer is also used. In addition, synthetic and natural resin films can be used. The basis weight of the support is determined by the final use of the ink jet recording medium, and is 100 to 30.
It is preferably 0 g / m ² , but is not particularly limited.

In the present invention, the magnetic recording layer is formed on one side of the support on which the ink jet recording layer is provided. This magnetic recording layer contains a magnetic powder and a binder resin.
As the magnetic powder, γ-iron oxide, cobalt-modified γ-iron oxide, barium ferrite, chromium oxide and the like can be used. Examples of the binder resin include polyvinyl alcohol and its derivatives, proteins such as casein, styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer, styrene-butadiene-methyl methacrylate copolymer, acrylic resin, and vinyl acetate. Latex or emulsion such as a series resin, polyurethane resin, vinyl chloride resin, polyester resin, vinyl chloride-vinyl acetate copolymer and the like can be used. The coating amount of the magnetic recording layer obtained in the present invention is determined depending on the final use, and is appropriately selected from the range of 20 to 40 g / m ² and used.

The magnetic paint containing these magnetic powder and binder as main components is prepared by using either an aqueous or organic solvent. As the organic solvent, any of commonly used organic solvents such as toluene, xylene and methyl ethyl ketone can be suitably used.

As for the concealing layer formed on the magnetic recording layer, the presence of the pearl pigment has a light interference reflection function to conceal the existence of the magnetic recording layer, thereby preventing forgery and tampering. Things.

The pearl pigment contained in the concealing layer of the present invention is a pigment constituted so as to exhibit pearl luster by coating a core material of a granular material with a special substance. Coated with a titanium compound is suitable. In the present invention, a mica powder coated with titanium dioxide (see, for example, Japanese Patent Application Laid-Open No. 60-60163) is preferable. The opaque layer has a pearl pigment dispersed uniformly in a vehicle.
And it is formed in a state of being oriented in parallel. here,
Depending on the thickness of the titanium dioxide, the pearl pigment interferes with any of the wavelengths of the incident visible light, and the reflected light has a specific hue. It should be noted that the same color of reflected light may be obtained by uniformly adjusting the film thickness of titanium dioxide of the pearl pigment to be used, or reflected light of various hues may be obtained by using a mixture of different film thicknesses. You may do so.

The titanium mica-based pearl pigment used in the present invention exhibits various interference colors depending on the thickness of the titanium dioxide coating layer on the surface of the mica particles. That is, when the amount of titanium dioxide is 10 to 26% by weight of the product, the interference color is usually silver, but when the amount is 26 to 40% by weight, the interference color is golden and 40 to 50% by weight.
In this case, the color changes to red, blue and green in the direction in which the titanium dioxide coating layer increases, and a high order interference color can be obtained at 50 to 60% by weight. At that time, the hue of the transmitted light is purple, yellow-green,
The color changes sequentially from orange to red.

As pearl pigments suitable for use in the present invention,
Mercury Japan's Iriodin (trade name), Shiseido Infinite Color (trade name), Nippon Koken's Pearl Glaze (trade name), and the like. The main material constituting the concealing layer may contain a binder in addition to the pearl pigment, and if desired, a dispersant, a preservative, an antifoaming agent, and a dusting inhibitor may be added. As the binder, any of resins commonly used in the fields of printing and coating, such as polyvinyl alcohol, polymethacrylic acid resin, vinyl chloride resin, cellulose resin such as polyester resin and nitrocellulose, can be suitably used. The thickness of the concealing layer is preferably 1 to 5 μm. Further, the pearl pigment particles are preferably 50 to 250 parts by weight per 100 parts by weight of the binder. If the coating amount is small, the concealing effect is naturally inferior, and if it is large, the recording / reproducing function of the magnetic recording layer is undesirably deteriorated.

The ink jet recording layer in the present invention comprises:
Consists of a coating composition containing a pigment and a binder as main components,
As additives to these, dye fixing agents, pigment dispersants, thickeners, flow improvers, defoamers, defoamers, release agents, foaming agents,
Properly blending penetrants, coloring dyes, coloring pigments, fluorescent whitening agents, ultraviolet absorbers, antioxidants, preservatives, anti-binders, water-proofing agents, wet paper strength agents, dry paper strength agents, etc. Can also.

As the pigment used in the ink jet recording layer, one or more known white pigments can be used. For example, light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic non-crystalline Amorphous silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, alumina, lithopone, zeolite,
White inorganic pigments such as hydrohaloysite, magnesium carbonate, and magnesium hydroxide, styrene plastic pigments, acrylic plastic pigments, polyethylene, microcapsules, and organic pigments such as urea resin and melamine resin can be used.

The amount of such a pigment is desirably 20 to 80% by weight based on the total solid content of the coating layer. If it is less than 20% by weight, the ink absorbency becomes insufficient, and if it exceeds 80% by weight, the strength of the coating layer may be reduced. It is unsuitable because it is rough to use and cannot be printed due to scratches, rubbing and the like.

Examples of the binder used for the ink jet recording layer include polyvinyl alcohol, vinyl acetate, oxidized starch, etherified starch, cellulose derivatives such as carboxymethylcellulose, hydroxyethylcellulose, casein, gelatin, soybean protein, and silyl-modified polyvinyl alcohol. A conjugated diene-based copolymer latex such as a maleic anhydride resin, a styrene-butadiene copolymer, a methyl methacrylate-butadiene copolymer; a polymer or copolymer of an acrylic ester and a methacrylic ester; acrylic acid and methacrylic acid Acrylic polymer latex such as polymer or copolymer of vinyl; latex of vinyl polymer such as ethylene vinyl acetate copolymer; or functional group such as carboxyl group of these various polymers Functional group-modified polymer latex according Yutan monomers; melamine resin, water-based adhesive such as a thermosetting synthetic resin such as urea resin; polymethyl methacrylate,
Synthetic resin-based adhesives such as polyurethane resin, unsaturated polyester resin, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, and alkyd resin are used, and one or more kinds are used.

[0027] The coating amount of the ink jet recording layer obtained in the present invention is determined by the final use, and the ink absorptivity,
It is not necessary to increase the amount unnecessarily as long as the recording characteristics, storage stability, etc. are satisfied, and it is appropriately selected from the range of 5 to 40 g / m ² and used. If the ink jet recording layer is less than 5 g / m ² , the ink absorption capacity is often insufficient, and the image flows out, the color bleeds, and the image is blurred.
Drying is slow and ink adheres to the roll and becomes dirty. However, when an ink jet recording layer exceeding 40 g / m ² is provided, the adhesion to the concealing layer is weakened due to the thick coating layer, which often causes a problem such as clogging of the head nozzle, and furthermore, the cost is low. It is not preferable because it becomes expensive.

Known coating equipment such as a bar coater, a roll coater, and an air knife coater can be used for coating for providing the ink jet recording layer, the concealing layer and the magnetic recording layer of the present invention. If necessary, printing and coating can be performed with an organic solvent system by a known coating method such as a gravure method or a screen printing method. The sheet obtained by laminating each layer on the support can be used as it is as the information recording medium of the present invention. For example, it can be treated with a super calender, a gloss calender or the like to impart surface smoothness. .

[0029]

EXAMPLES The present invention will be described more specifically with reference to the following examples, but it should be understood that the present invention is not limited by these examples. In the following, parts and% all indicate parts by weight and% by weight.

Example 1 18 parts of light calcium carbonate was added to a slurry of 100 parts of hardwood bleached kraft pulp, and 1.7 parts of cationic starch was added.
Parts, an alkenyl succinic anhydride-based neutral sizing agent (0.3 parts) was added and mixed well to obtain a papermaking raw material. A 7% solution of starch was coated on both sides at 4 g / m ² and dried to produce a fine paper having a basis weight of 200 g / m ² .

Paint-1 Ba-ferrite (2700 Oersted holding power) 100 parts Styrene-butadiene latex 30 parts Water 200 parts Paint-2 synthetic amorphous silica 100 parts Polyvinyl alcohol 30 parts Cationic dye fixative 20 parts Water 400 A coating material-1 was applied to one side of the obtained high quality paper using a test bar coater so as to have a coating weight of 20 g / m ² and dried to form a magnetic recording layer. Further, as a pearl pigment-containing hiding layer,
Iriodin (product name) 20 manufactured by Merck Japan Ltd.
Of nitrocellulose and 10 parts of nitrocellulose in 70 parts of medium so as to have a coating thickness of 5 μm after drying, followed by 5 g / m ² of paint-2 on the same surface.
And dried to form an ink jet recording layer to produce an ink jet information recording medium.

Example 2 Paint-1 was applied to one side of a multi-layered synthetic paper containing an inorganic pigment using a test bar coater so as to be 30 g / m ² , and dried to form a magnetic recording layer. Furthermore, as a pearl pigment-containing hiding layer, 25 parts of Shiseido Infinite Color (trade name) and 10 parts of nitrocellulose were added to a medium 65.
The coating thickness after drying with the ink mixed in the part is 3 μm
Was applied. Then paint-2 on the same surface
Was applied to 10 g / m ² and dried to form an ink jet recording layer, thereby producing an ink jet information recording medium.

Example 3 A coating paper-1 was applied to one side of a multi-layered synthetic paper containing an inorganic pigment using a test bar coater so as to be 35 g / m ² and dried to form a magnetic recording layer. Further, as a pearl pigment-containing concealing layer, the coating thickness after drying with an ink obtained by mixing 20 parts of Nippon Koken's Pearl Glaze (trade name) and 15 parts of nitrocellulose in 65 parts of medium was adjusted to 3 μm. Applied. Then paint-2 on the same surface
Was applied at 15 g / m ² and dried to form an ink jet recording layer to produce an ink jet information recording medium.

Comparative Example 1 Paint-1 was applied to one side of the high-quality paper used in Example 1 using a test bar coater so as to be 30 g / m ² , and dried to form a magnetic recording layer. Then paint-2 on the same surface
Was applied to 12 g / m ² and dried to form an ink jet recording layer to produce an ink jet information recording medium.

Comparative Example 2 Paint 1 was applied to one side of the synthetic paper used in Example 2 using a test bar coater so as to have a coating weight of 35 g / m ² and dried to form a magnetic recording layer. Subsequently, in the same manner, paint-3 was applied on the same surface so as to be 11 g / m ² and dried.
An inkjet recording layer was formed to produce an inkjet information recording medium. Paint-3 Calcium carbonate pigment 100 parts Polyvinyl alcohol 40 parts Water 400 parts

Comparative Example 3 Paint 1 was applied to one side of the synthetic paper used in Example 3 using a test bar coater so as to have a coating weight of 32 g / m ² and dried to form a magnetic recording layer. Further, the coating material-4 was applied so that the coating thickness after drying became 6 μm to provide a concealing layer. Subsequently, paint-2 was applied so as to be 11 g / m ² ,
It dried and formed the inkjet recording layer, and the inkjet information recording medium was manufactured. Paint-4 Organic pigment Yellow 1.5 parts Magenta 1.5 parts Cyan 1.7 parts Polyester resin 2.5 parts Toluene 25.0 parts

Comparative Example 4 Paint-1 was applied to one side of the synthetic paper used in Example 2 using a test bar coater so as to be 30 g / m ² , and dried to form a magnetic recording layer. Further, Paint-3 was applied on the same surface so as to be 12 g / m ² and dried to form an ink jet recording layer, thereby producing an ink jet information recording medium.

Table 1 shows the evaluation results of these recording sheets. The ink jet recording characteristics were printed using an ink jet printer (Desk Writer-550C: manufactured by Hewlett-Packard Co.), and the print density was measured using a Macbeth densitometer by printing 2 cm × 2 cm solid with black ink.

The magnetic layer shielding effect was evaluated by visually checking the non-image area. The color of the magnetic recording layer was completely concealed and the presence was not sensed, and the presence was not perceived. The color of the magnetic recording layer was poorly observed, and the color of the magnetic recording layer was observed almost through the ink jet recording layer. .

Magnetic Recording Property 100 samples obtained in Examples and Comparative Examples were passed through a commercially available reader / writer device, and magnetic recording was performed at a recording density of 52.5 bits per inch. The difference between the minimum output values was measured. The smaller the numerical value, the smaller the magnetic output fluctuation and the better the magnetic recording performance.

[0041]

[Table 1]

As can be seen from Table 1, the ink jet information recording media of Examples 1 to 3 have excellent magnetic layer concealing effects and can reduce magnetic output fluctuations in magnetic recording to obtain good magnetic recording properties. Was. On the other hand, the concealing effect of Comparative Example 3 in which the pigment concealing layer was provided was insufficient and was not as effective as the pearl pigment-containing layer, but the magnetic recording characteristics were inferior due to the thickness of the concealing layer. In Comparative Examples 1, 2, and 4, in which the concealing layer was not provided, the magnetic recording properties were not deteriorated, but there was no magnetic layer concealing effect, and problems remained in the forgery and falsification prevention properties.

[0043]

The ink jet information recording medium of the present invention has a magnetic recording function and an ink jet information recording function, and the magnetic recording layer is invisible and concealed.
Moreover, by maintaining the recording function of the magnetic recording layer at a high level, it is excellent in the function of preventing forgery and falsification.

Claims (2)

[Claims] 1. An ink-jet information recording medium having a support, a magnetic recording layer, and an ink-jet recording layer in this order, wherein a concealing layer that makes the magnetic recording layer invisible is provided between the magnetic recording layer and the ink-jet recording layer. An ink jet information recording medium characterized by the following. 2. The ink jet information recording medium according to claim 1, wherein said concealing layer contains pearl pigment particles which develop color by interference of light.