JPH05177920A - Magnetic printed matter - Google Patents

Abstract

PURPOSE:To obtain a print, which is useful for anti-fabrication and anti- falsification, by a method wherein colloid, which is prepared by coveringly separating pulverized magnetic material with surface-active agent, is enmicrocapsulated and mixed with ink vehicle or the like for application. CONSTITUTION:The printed matter concerned is produced by providing two ink layers, one of which is prepared by mixing microcapsules 1 in ink vehicle or binder 4 and the other of which is prepared by printing with ink b having the same color as that of the ink, on matter to be printed 5. The microcapsule 1 is obtained by enmicrocapsulating colloid, which is prepared by dispersing pulverized magnetic material covered with surface-active agent. When a permanent magnet 7 is brought into contact with the rear surface of printed matter produced as mentioned above, the concentration of the microcapsule 1 turns to be transparent, resulting in emerging of the printed matter produced with the ink 6. With the passing of the permanent magnet 7, the concentration of the microcapsule turns to its initial state. Thus, since the reproduction of the magnetic printed matter with copier, is difficult photoengraving process or the like becomes difficult, so the magnetic printed matter is useful for anti- fabrication and anti-falsification.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed matter which visually changes due to a magnetic action, and more particularly to a magnetic printed matter which can be easily identified by a normal permanent magnet or the like as means for preventing forgery and falsification and authenticity determination.

[0002]

2. Description of the Related Art Conventionally, magnetic printed matter has been mainly introduced for machine reading, and has been widely used by being widely applied to automatic vending machines and automatic ticket gates. A magnetic printed matter such as a train ticket or a telephone card is one in which a dedicated writing device is used to give an electrical or magnetic signal to write necessary information and the dedicated reading device reads the information.

[0003]

The conventional magnetic printed matter for machine reading requires a dedicated expensive writing and reading apparatus, and the added information cannot be known from the appearance. This is convenient when it is desired to keep the recorded information secret, but it has the drawback that a dedicated device is required to determine the authenticity of the magnetic print. In addition, there are many factors that limit the form and use of the printed matter due to the use of the machine, which may limit the application and handling. The present invention is based on a completely new idea in consideration of the above restrictions, and the magnetic printed material is not used as a recording medium for writing information by giving an electric or magnetic signal, that is,
The density of the printed matter changes without using a machine for writing and reading, just by using an inexpensive ordinary permanent magnet, etc.By visually checking it, it is possible to easily and nondestructively determine the authenticity. Another object of the present invention is to provide a magnetic printed material that can be used in various forms and purposes.

[0004]

The magnetic printed material of the present invention comprises:
It is obtained by coating a finely divided magnetic material with a surfactant and dispersing the colloid into microcapsules, and mixing the microcapsules with an ink vehicle or a binder for use.

[0005]

The magnetic printed material of the present invention is a printed material which can be identified by forming a desired magnetic field on the printed material, the density of which changes due to the magnetic action of an ordinary permanent magnet, and the authenticity of the printed material can be determined nondestructively. Therefore, it can be used as an effective means for preventing forgery and tampering.

[0006]

EXAMPLES The present invention will be described in more detail by way of examples, which should not be construed as limiting the invention thereto.

Example 1 Colloids essential to the present invention are cholesteryl chloride 13 to 14 parts, cholesteryl n-nonanoate 40 to 42 parts, cholesteryl 2-ethylhexanoate 7 parts, and p-methoxybenzylidene-p-. Liquid crystal material consisting of 32 to 33 parts of butylaniline (hereinafter abbreviated as MBBA), 0.05 parts of 3-tert-butyl-4-hydroxyanisole (hereinafter abbreviated as BHA), butylhydroxytoluene (hereinafter abbreviated as BHT) 0.05 part, Mn
-Zn-ferrite powder 4 to 8 parts by dispersion, in addition to cholesteryl oleate 33 parts, MBBA 66 parts liquid crystal material BHA 0.05 parts, BHT 0.05 parts, Fe
-Prepared by a method of dispersing 1 part of ferrite powder.
These were microcapsulated by a coacervation method using gelatin and gum arabic wall film-forming material, and the resulting capsule slurry was filtered after improving dispersibility with decantation, a stabilizer, etc., and then using polyvinyl alcohol. It was dispersed in a hydrophilic binder such as (hereinafter abbreviated as PVA) to form an ink, which was printed on coated paper using a 100-mesh silk screen. When a permanent magnet was brought close to the printed matter, a good density change was obtained due to the effect of the liquid crystal material, and a magnetic printed matter that could be identified by forming a desired magnetic field on the printed matter was obtained.

(Example 2) Collagen was prepared by dispersing 0.05 part of BHA, 0.05 part of BHT and 4-9 parts of Ba-ferrite powder in a liquid crystal material consisting of 18-29 parts of cholesteryl oleate and 67-73 parts of MBBA. It was made. Using these wall material of gelatin and gum arabic,
Microcapsules by coacervation method, and the resulting capsule slurry is filtered by improving the dispersibility with decantation, stabilizers, etc., and then dispersed in a PVA binder, and coated on 100-mesh silk screen coated paper. Printed. When a permanent magnet was brought close to the printed matter, a good density change was obtained due to the effect of the liquid crystal material, and a magnetic printed matter that could be identified by forming a desired magnetic field on the printed matter was obtained.

(Example 3) When a permanent magnet was brought into contact with the back surface of a printed matter, a printed matter in which a hidden pattern could be identified was prepared. The glue is Shin-Etsu Silicone 100 cp [Shin-Etsu Chemical Co., Ltd.] and Toray SF Silicone [Toray Silicone Co., Ltd.] 49.
Medium or acrylic resin Aronix M-
It was prepared by a method of dispersing 2 to 5 parts of Fe-ferrite powder in a dispersion medium of 7100 [Toagosei Kagaku Co., Ltd.]. Using a wall film forming substance of melamine resin, these are microencapsulated by an in situ polymerization method, the obtained capsule slurry is treated with decantation or a stabilizer, and then dried by a spray dryer to be powdered, The ink was dispersed in a lipophilic binder such as medium. In advance, a pattern to be a hidden pattern was printed on a coated paper with an offset ink having the same color as that of the ink, and a 100-mesh silk screen was used to print a pattern on the coated paper so as to be hidden by the ink. When a permanent magnet was brought into contact with the back surface of this printed material, the area printed with the ink became transparent, and a good printed material in which the hidden pattern of the base could be identified was obtained.

Next, as the wall film forming substance of the microcapsule (1), for example, gelatin, shellac, gum arabic, rosin, rosin ester, ethyl cellulose, carboxymethyl cellulose, paraffin, tristearin, polyvinyl alcohol, polyethylene, polypropylene, acryl. Resin, vinyl resin, polyisobutene, polybutadiene, epoxy resin, phenol resin,
Polyurethane, polyester, polyamide, silicone, polystyrene, melamine resin can be used alone or in combination, as a microencapsulation method,
For example, a coacervation method, an interfacial polymerization method, an in situ polymerization method, a liquid hardening film method, a phase separation method from an organic solvent, a liquid drying method, an air suspension coating method, a spray dry method, or the like can be used. It can be carried out. Further, the capsule slurry is treated with decantation or a stabilizer, filtered or pulverized, and dispersed in an appropriate ink vehicle or binder to obtain an ink.

Examples of the surfactant include fatty acid metal salts, fatty acid metal ammonium salts, glycerin-1-acyl ester, 33.6-dinonylnaphthalene sulfonic acid, sulfosuccinic acid-1,4-bis (2-ethylhexyl). An oil-soluble substance such as 2-sodium or an alkyl ammonium salt can be used.

As the ultrafine magnetic material (2), any magnetic material made of a ferromagnetic material and having an average particle diameter of about 0.10 to 1.00 μm can be used. For example, Fe, Fe-Si,
Fe-Al, Fe-Al-Si, Fe-Ni, Fe-C
Metals or alloys such as o, M-ferrites (MFe2O
4, M = Mn, Fe, Co, Ni, Cu, Mg, Li.
5Fe. 5, Mn-Zn, Ni-Zn, Cu-Zn
Others), iron garnets, chromites, Ba2 +, Sr
2+, Pb2 + and other magnetoplumbites are atomized and surface-treated with a surfactant. The shape of the magnetic material is spherical, cubic, acicular, irregular (granular), octahedral or disk-like, and has a color of black, brown or brown.

As the dispersion medium (3), any one can be used as long as it has suitable viscosity and dispersibility. For example,
Oils and fats such as linseed oil, olive oil, castor oil, sunflower oil as ordinary ink vehicle or binder,
Natural waxes such as whale wax, beeswax, lanolin, carnauba wax, candelia wax, montan wax, paraffin wax, microcrystalline wax, oxidation wax, ester wax, synthetic waxes such as low molecular weight polyethylene, lauric acid, myristic acid , Higher fatty acids such as palmitic acid, stearic acid, flomenic acid, hebenic acid, stearyl alcohol,
Higher alcohols such as hevenyl alcohol, soaps such as petrolatum and glycerin, hydrocarbons such as glucose, ethylene glucose and amylose, esters such as fatty acid esters, amides such as stearamide and oleinamide, polyamide resins, Polyester resin, epoxy resin, polyurethane resin, acrylic resin, vinyl chloride resin, cellulose resin, polyvinyl resin, petroleum resin, ethylene-vinyl acetate copolymer resin, phenol resin, styrene resin , Resins such as rosin-modified resin, terbine resin, elastomers such as natural rubber, styrene-butadiene rubber, isoprene rubber, chloroprene rubber, hydrogenated petroleum resin, silicone,
Liquid paraffin, a tackifier such as a fluororesin, or a dispersion medium composed of a mixture thereof can be used. Further, if necessary, a pigment, a dye, a surfactant, a filler, an antioxidant, a desiccant, etc. may be added to the dispersion medium for use.

In addition to the dispersion medium, for example, a Schiff nematic liquid crystal such as p-methoxybenzylidene-p-butylaniline (MBBA) or a cyanobiphenyl nematic liquid crystal (having 2 to 7 carbon atoms in the alkyl group and an alkoxy group C3, 5), terphenyl nematic liquid crystal (alkyl group carbon number 5), cholesteryl chloride, cholesteryl bromide, cholesteryl acetate, cholesteryl 2-ethylhexanoate, cholesteryl n-nonanoate, cholesteryl oleate, linole. Cholesteryl acid, Cholesteryl decanonate, Cholesteryl laurate, Cholesteryl isobutyrate, Cholesteryl myristate, Cholesteryl carbonate carbonate, Nonylcholesteryl carbonate, Methylcholesteryl carbonate, Ethylcholesteryl carbonate, Butylcholesteryl carbonate, Isocarbonate Using a magnetic field-sensitive liquid crystal material consisting of those b are single or mixed, such as pills cholesteryl, more effective visual change is obtained. Further, if necessary, a pigment, a dye, a dichroic dye, a preservative or the like may be added to the liquid crystal material before use.

FIG. 1 is a diagram illustrating an example of the structure of a microcapsule (1) in which a colloid composed of an ultrafine magnetic material (2) coated with a surface-active agent and a dispersion medium (3) is encapsulated and behavior by a magnetic action. Is. In the collagen before applying the magnetic field (H), it is assumed that the magnetic materials are arranged as shown in FIG. The white circle in the microcapsule (1) indicates the ultrafine magnetic material (2), and the arrow indicates the direction of magnetization of the ultrafine magnetic material (2). Macroscopically, the color of the microcapsules (1) is turbid. When a magnetic field (H) is applied in this state, the entire microcapsules (1) encapsulated in the collagen are turned 90 degrees as shown in FIG. 1 (B),
Macroscopically, the concentration of the microcapsules (1) changes transparently or semi-transparently in the direction of the magnetic field (H). It should be noted that those in which the ultrafine magnetic material (2) is inverted are indicated by black circles for distinction. Next, after the magnetic field (H) is removed, the entire magnetic field is further turned by 90 degrees to reach equilibrium in the state as shown in FIG. 1 (C), for example. The black circles indicate the case where the ultrafine magnetic material (2) is inverted due to mutual magnetic action. Macroscopically, the color of the microcapsule (1) seems to be inverted again, but this change is not as rapid as when a magnetic field is applied, and the previous color remains for a while and gradually changes color. ..

FIG. 2 is a sectional view showing the structure and operating principle of the magnetic printed material of the present invention. The printed matter shown in the figure is obtained by mixing the microcapsules (1) with an ink vehicle or a binder (4) to form an ink, and printing it on a substrate (5) by offset printing. FIG. 2A shows a state of the printed matter before the magnetic field (H) is applied, and FIG. 2B is a diagram when the magnetic field (H) is applied to the printed matter, in which the microcapsules (1) under the magnetic field are The density changes to transparent or translucent, and the color of the printed matter appears to change.

As the material to be printed (5) in FIG. 2, any material having sufficient self-holding property can be used. For example, high-quality paper, coated paper, medium-quality paper, neutral paper, Japanese paper, recycled paper. In addition to plain paper such as paper, paper-like objects such as trace paper and glassine paper, film-like objects such as cellophane paper and Freon film, sheet-like objects such as polyethylene, polyprene, vinyl chloride, polyurethane and Teflon sheets, Fluorine rubber, isoprene rubber, butyl rubber, silicone rubber, latex-like substances such as natural rubber, polyester, polyamide, polyamideimide, polyethylene, polypropylene, cellulose acetate, polycarbonate, polyvinyl chloride, resin plate-like substances such as fluororesin, It is possible to print on metal foil-like objects such as aluminum foil, but the surface glossiness is similar to that of coated paper. Excellent those are preferably used.
Further, although permanent magnets such as metal magnets and ferrite magnets are used for applying the magnetic field, the magnetic field may be generated by electromagnetic waves such as an air-core coil, a multi-pole capacitor, an iron core coil, and a cylindrical coil. ..

FIG. 3 is a sectional view showing the structure and operating principle of the printed matter of (Example 3). The printed matter shown in the figure has two layers, an ink layer in which microcapsules (1) are mixed in an ink vehicle or a binder (4) on an object to be printed (5) and an ink layer printed with an ink (6) of the same color as the ink. Consists of. FIG. 3A shows a printed matter before the permanent magnet (7) is contacted. FIG. 3B shows the state of the printed matter when the permanent magnet (7) is in contact with the back surface of the printed matter. The density of the microcapsules (1) changed to transparent,
Printed matter using the ink (6) appears. Figure 3 (C)
Shows the state in which the concentration of the microcapsules (1) returns to the original level after the permanent magnets (7) have passed.

[0019]

INDUSTRIAL APPLICABILITY The magnetic printed material of the present invention is a printed material whose density is changed by the magnetic action of an ordinary permanent magnet and a desired magnetic field is formed on the printed material for identification. Particularly, in a system in which a magnetic material is dispersed in a magnetic field sensitive liquid crystal material, an effective visual change is observed, and a printed matter with a high added value can be obtained by combining with a printed matter such as a hidden pattern. As described above, it is difficult to copy this magnetic printed material by a copying machine, photoengraving, etc., and it is very effective as a countermeasure against falsification and forgery.

[Brief description of drawings]

FIG. 1 is an explanatory view showing the structure and principle of microcapsules used for a magnetic printed material of the present invention.

FIG. 2 is a cross-sectional view showing the structure and operating principle of the magnetic printed material of the present invention.

FIG. 3 is a cross-sectional view showing the configuration and operating principle of an application example of the magnetic printed material of the present invention.

[Explanation of symbols]

 1 Micro Capsule 2 Ultrafine Magnetic Material 3 Dispersion Medium 4 Ink Vehicle or Binder 5 Printed Object 6 Ink 7 Permanent Magnet

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location G11B 5/80 7303-5D

Claims (3)

[Claims] 1. A printed matter containing a magnetic material, the density of which changes by a magnetic action. 2. The printed matter according to claim 1, wherein the colloid obtained by coating and dispersing a magnetic material with a surfactant is encapsulated in microcapsules. 3. The printed matter according to claim 1, wherein a magnetic field sensitive liquid crystal material is enclosed in microcapsules.