Magnetic information recording medium

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Technical field to which the invention belongs]

The present invention relates to a magnetic information recording medium having magnetic information such as a credit card or a cash card that requires an anti-counterfeiting effect. More specifically, the present invention relates to a magnetic information recording medium having an OVD on which an OVD image is formed in order to impart an anti-counterfeiting effect to the information recording medium.

【0002】

[Conventional technology]

Like a multilayer thin film that changes color (color shift) depending on the viewing angle by superimposing holograms, diffraction gratings, and thin films with different optical characteristics that can express stereoscopic images and special decorative images using light interference. Development of OVD (Optical Variable Device) is in progress.

【0003】

OVDs such as holograms and diffraction gratings have a diffraction structure such as a fine uneven pattern or a striped pattern with different refractive coefficients, which supports the angle seen by light diffraction and interference (that is, the hologram is supported. Depending on the angle), a unique image or color change (color shift) occurs. On the other hand, the multilayer thin film has a structure in which ceramics and metal materials having different optical characteristics are laminated in multiple layers. This multilayer thin film is a display technology that utilizes the optical characteristics of the constituent materials and the interference of light obtained by the film thickness. Since it has reflection / transmission characteristics in a specific wavelength range, color shift can be performed depending on the observation angle. Occurs.

【0004】

In the present specification, display techniques utilizing light interference such as holograms, diffraction gratings, and multilayer thin films are collectively referred to as OVD.

【0005】

Since these OVDs give a unique impression such as stereoscopic images and color shifts, they have an excellent decorative effect and are used for general printed matter such as various packaging materials, picture books, and catalogs. Furthermore, since this OVD requires advanced manufacturing technology, it is formed and used in credit cards, securities, certificates, etc. as an effective anti-counterfeiting means. Recently, paying attention to the decorative effect of OVD, some have been formed on the entire surface of the medium.

【0006】

On the other hand, cash cards and credit cards, which are information media having a magnetic information recording unit, have been attempted to conceal the color of the magnetic tape, which is black or brown, and to make a card without design restrictions. As the method, a method of matching the color of the card itself with the color of the magnetic tape or a method of printing a pattern after applying a concealing ink such as white, black or silver from above is adopted. In the former case, there is a problem that the design is limited because the color is limited. Although the latter method widens the range of design, there is a problem that the magnetic output is lowered due to the thickening of the concealment and printing. In particular, when the pattern printing layer and the above-mentioned OVD are formed, there is a problem that the output is lowered due to the increase in the thickness of the OVD and a reading error is likely to occur. To give a specific example, a magnetic card such as a credit card having a magnetic stripe depends on the performance of the magnetic tape, but generally, the distance between the embedded magnetic tape and the surface of the card is limited to about 6 μm, which is less than that. There is a problem that it must be done.

【0007】

Such a magnetic information recording medium to which an OVD having a high anti-counterfeiting effect was added was a medium that was difficult to read. According to JP-A-9-29443, it is proposed that the concealing layer is thinned by forming a metal thin film such as Al or Ni, and the output does not decrease even if an optical diffraction image (hologram or diffraction grating) is formed. ing. However, this configuration is a structure in which a metal that is a conductor and a plastic material that is an insulator are laminated on the information medium, and because of the structure in which electric charges easily accumulate, various problems due to static electricity occur during processing and magnetic information. The configuration was such that an error was likely to occur due to the discharge of electric charge when writing or reading.

【0008】

[Problems to be Solved by the Invention]

The present invention has been made in view of the above problems, and prevents writing and reading errors of magnetic information due to static electricity and defects during processing even in a magnetic information recording medium having an OVD having excellent decorativeness. An object of the present invention is to provide a magnetic information recording medium capable of performing the above.

【0009】

[Means for solving problems]

The present invention has been made to achieve the above object, and by using a concealing layer having a matte surface on a magnetic information medium having an OVD, the card does not interfere with the reading and writing of magnetic information. The feature is that the magnetic medium provided in the shape is visually concealed and the degree of freedom in the design shape is expanded.

【0010】

That is, in the invention according to claim 1, in an information medium having at least a magnetic layer, a concealing layer, and an OVD layer capable of recording magnetic information on a recording medium base material having magnetic information, the concealing layer has conductivity. It is a magnetic information recording medium that does not have a thin film and has a matte surface. By making the surface matte, the metallic luster can be suppressed as compared with the case where a metal thin film is simply provided, and the thickness of the thin film can be reduced by scattering light, so that writing and reading errors are reduced. In addition, since a color tone close to white can be obtained, design selectivity can be expanded.

【0011】

The invention according to claim 2 is the magnetic information recording medium according to claim 1, wherein the thin film constituting the concealing layer is made of a metal thin film having an island-like structure. In this thin film, each island exhibits conductivity, but since the islands are separated from each other, the film itself does not exhibit conductivity. For this reason, electric charges are less likely to accumulate, and electrostatic damage is less likely to occur.

【0012】

The invention according to claim 3 is the magnetic information recording medium according to claim 1, wherein the thin film constituting the concealing layer is made of a dielectric thin film such as a metal oxide. Since the dielectric thin film is an insulator, as in claim 2, it is difficult for electric charges to accumulate and electrostatic damage is unlikely to occur.

【0013】

Further, in the inventions according to claims 4, 5 and 6, when the concealing layer is provided, the adherend surface is made into a matte shape by an embossing method by heat pressure, a matte shape by a sandblasting method, an inorganic filler, a coloring pigment or the like. The magnetic information recording medium according to claim 1, which is characterized in that it has a matte shape.

【0014】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, description will be made in detail with reference to the drawings according to the embodiment of the present invention.

【0015】

FIG. 1 shows an embodiment of the magnetic information recording medium of the present invention, (A) is a plan view, and (B) is a cross-sectional view of the magnetic information recording medium of (A) on line XX. Hereinafter, a detailed description will be given using these figures.

【0016】

The magnetic information recording medium (10) shown in FIG. 1 includes a concealing layer (13), an OVD layer (14), and a printing layer (13) matted on a magnetic information recording medium base material (11) having a magnetic layer (12). 15), the protective layer (16) is provided, and on the outside, only the patterns and characters of "" and "IDCARD" printed on the print layer and the pattern of "BANK" which is OVD (14) are confirmed. Can not. The magnetic layer is below the concealing layer and cannot be seen.

【0017】

Examples of the magnetic information recording medium base material (11) having the magnetic layer (12) include synthetic resins such as polyethylene terephthalate, polyethylene naphthalate, polyvinyl chloride, polyester, polycarbonate, polymethyl methacrylate, and polystyrene, or natural resins. It has a structure in which a magnetic layer capable of reading and writing magnetic information is provided on the entire surface or a part of a composite of paper, synthetic paper, etc. alone or in combination, and is matted on the magnetic information recording medium base material (11). Since the concealing layer (13), OVD layer (14), printing layer (15), and protective layer (16) are laminated, strength that can withstand the processing, heat resistance, and resistance according to the method of use are required. .. Therefore, the material is not limited to the above materials, and is appropriately selected according to the processing method. Further, the thickness and shape thereof are not particularly limited because they differ depending on the product form, but if the medium has a standard such as a cash card or a credit card, it is necessary to comply with the standard.

【0018】

The concealing layer (13) is a layer that conceals the magnetic layer (12) and is a non-conductive thin film. For example, a metal thin film having an island-like structure and a thin film made of a ceramic material can be mentioned. Hereinafter, these will be described in more detail. A metal thin film having an island-like structure is a thin film in which particles having a size of 0.02 to 1 μm as shown in FIG. 6 are formed in an isolated island shape with an interval of about 0.001 to 0.5 μm, and the islands are separated from each other. Therefore, the entire thin film does not show conductivity. In addition, since the interval is very small, the entire film exhibits a property of reflecting light, and the magnetic layer (12) can be concealed.

【0019】

This thin film can be directly formed by a thin film forming method such as vacuum deposition, sputtering, or ion plating (Japanese Patent Publication No. 6-6783). Sn, Sn-Al alloy, Sn-Si alloy, Ti, Cr, Fe , Ni, Co, Si, Ge and the like, but metals and noble metals having a low melting point are suitable for processing, and Sn, Sn-Al alloys and Sn-Si alloys are preferable.

【0020】

Another method for forming an island-shaped thin film is to form a continuous thin film even if it is difficult to deposit an island-shaped structure such as Al, and then etch it to form an island-shaped structure. It is also possible to remove the thin film and manufacture it. Any method other than these can be used as long as it is a known method capable of forming thin films having independent island structures, and the method is not limited.

【0021】

On the other hand, the concealing layer using a dielectric material such as metal oxide or sulfide is, for example, TiO.₂, Si₂O₃, SiO, SiO₂, Fe₂O₃, ZnS, MgO, Al₂O₃, AlF₃Ceramic materials can be mentioned. These materials vary depending on the color tone and the degree of light transmission, but are provided by a known thin film forming method such as vacuum deposition, sputtering, or ion plating in the range of 200 Å to 10000 Å.

【0022】

These materials do not exhibit conductivity, and a medium that is less likely to cause defects due to static electricity can be obtained, but all of them have high transparency and poor concealment. However, TiO₂, Si₂O₃, ZnS and other materials have different refractive indexes from plastic materials, so when laminated with plastic materials, they have the property of reflecting light at their boundaries. By utilizing this characteristic, the surface on which the thin film is formed is finely roughened in advance to increase the light reflection area, and further the reflected light is scattered, so that a white concealing layer can be obtained.

【0023】

FIG. 1B is a cross-sectional view showing an embodiment of the magnetic information recording medium of the present invention, and is a cross-sectional view showing an example in which the concealing layer (13) is formed on a rough surface surface. 13) Light can be reflected and scattered on the surface to conceal the magnetic layer (12).

【0024】

FIG. 2 shows a concealing layer transfer foil (20) for producing the magnetic information recording medium of the present invention shown in FIG. As shown in the figure, a concealing layer (22) is coated on the support (21) of the concealing layer transfer foil with a plastic material that can be easily peeled off, vapor-deposited with the above-mentioned ceramic material, and the surface is matted. 23), after the adhesive layer (24) is provided, the magnetic information recording medium can be transferred to the magnetic information recording medium base material to produce the magnetic information recording medium shown in FIG.

【0025】

It is also possible to roughen the surface and improve the concealing effect by mixing particles such as an inorganic filler and a coloring pigment into the material of the release layer (22). The above is an example, and the method is not limited to these as long as it is a method of forming a thin film on a roughened surface. In addition, this method has the effect of improving the hiding power and whitening or coloring, and is also applicable to the metal thin film having the above-mentioned island structure. It is also possible to make the magnetic layer inconspicuous and then provide the concealing layer by printing for concealment in order to further enhance the concealing property or by matching the color of the base material with the color of the magnetic layer.

【0026】

The print layer (15) should be above the OVD layer so that it is not obscured by the OVD layer (14). Therefore, in FIG. 1, the print layer (15) is provided between the protective layer (16) and the OVD layer (14). However, if the OVD layer is transparent and the patterns, characters, etc. of the print layer can be read, the print layer may be provided between the OVD layer (14) and the concealment layer (13).

【0027】

In the magnetic information recording medium (10) shown in FIG. 1, the part indicated by printing "IDCARD" or "" is the print layer, and visually recognizable information and background of characters, symbols, characters, etc. are printed. To. This printing layer is provided by a known material and printing method, but since the printing layer (15) is on the magnetic layer (12), if it is formed thick, it causes a decrease in magnetic output, so it should be about 1 to 3 μm. It is preferable to provide it. The print layer (15) is not an essential configuration requirement, and may be provided when necessary depending on the application.

【0028】

Next, the OVD layer (14) will be described in detail. The OVD layer (14) is a layer that forms an OVD image using the above-mentioned light interference, and is a layer that forms a display body that causes a color shift in which the color changes depending on the expression of a stereoscopic image and the viewing angle. Among them, examples of OVDs such as holograms and diffraction gratings include a relief type in which light interference fringes are recorded as a fine uneven pattern on a flat surface and a volume type in which interference fringes are recorded in the volume direction.

【0029】

The relief type is generally a relief type master hologram composed of fine uneven patterns by an optical photographing method, and then a nickel press plate in which the uneven patterns are duplicated by an electroplating method is duplicated, and this press is performed. Mass replication is performed by a well-known method of heating and pressing the plate onto the hologram cambium. This type of hologram is called a relief hologram.

【0030】

Further, unlike the relief type hologram, there is also a so-called volume type hologram in which interference fringes are recorded in the volume direction by using a recording material such as a photosensitive resin. In this type of hologram, what is called a Lippmann hologram is generally used, and this is a reflective hologram in which the refractive index of the photosensitive resin is changed in the volume direction.

【0031】

Furthermore, unlike a hologram image that can reproduce this stereoscopic image, a diffraction grating image such as a grating image or a pixel gram that expresses an image by arranging a plurality of types of simple diffraction gratings in a minute area to form pixels is also a relief. Mass replication is performed in the same way as a type hologram, while thin films of ceramics or metal materials with different optical characteristics are laminated, which is different from holograms and diffraction gratings, and color changes (color shift) occur depending on the viewing angle. The multilayer film method is also an example. Among these OVDs, a relief type hologram (diffraction grating) or a multilayer thin film type is preferable in consideration of mass productivity and cost. Hereinafter, the magnetic information recording medium using these will be described in detail.

【0032】

3 and 4 show cross-sectional views illustrating an embodiment of the magnetic information recording medium of the present invention in the form of an OVD. FIG. 3 shows an example in which a relief-type hologram or diffraction grating is used as an OVD. A matted concealing layer (33) and an OVD are formed on a magnetic information recording medium base material (31) having a magnetic layer (32). The structure is provided with a layer (34), a printing layer (35), and a protective layer (36). In this case, the OVD layer (34) is composed of an OVD cambium (34a) and an OVD effect layer (34b), and the OVD effect layer (34b) is a highly refracting material thin film that reflects light so that more diffraction efficiency can be obtained. It consists of a metal thin film.

【0033】

Further, FIG. 4 shows a cross-sectional view of a multilayer film configuration that causes color shift as OVD, and the OVD layer (44) is a multilayer film configuration of thin films (44a, 44b, 44c) having different optical characteristics. .. As described above, the structure of the OVD layer differs depending on the OVD forming method, and a plurality of materials are laminated depending on the form. Therefore, the configuration is not limited to FIGS. 3 and 4, but is an embodiment.

【0034】

The relief type hologram (diffraction grating) is a method in which a press plate having a fine uneven pattern is heated and pressed against an OVD cambium (34a) as described above to duplicate the pattern. Therefore, the OVD forming layer (34a) is a material that has good moldability by heat, is less likely to cause press unevenness, and can obtain a bright reproduced image, and is a thermoplastic resin such as a polycarbonate resin, a polystyrene resin, or a polyvinyl chloride resin. Thermosetting resins such as unsaturated polyester resins, melamine resins, and epoxy resins, or ultraviolet or electron beam curable resins having radically polymerizable unsaturated groups can be used alone or in combination. In addition, any material other than the above can be appropriately used as long as it is a material capable of forming an OVD relief pattern.

【0035】

When a relief type hologram (diffraction grating) is used, a reflective layer (OVD effect layer (34b)) having a refractive index different from that of the polymer material used in the OVD cambium (34a) is used to improve the diffraction efficiency. It is preferable to provide it. By providing this OVD effect layer (34b), the diffraction efficiency is improved, and a clearer image and color change are brought about. The material used is TiO with different refractive indexes.₂, Si₂O₃, SiO, Fe₂O₃, ZnS, and other high-refractive index materials and Sn, Al, and other island-like thin films having a higher reflective effect can be mentioned, and these materials can be used alone or in combination. As described above, these layers are made of materials that do not exhibit conductivity, and are not limited thereto. These materials are formed by a known thin film forming technique such as vacuum deposition or sputtering or an etching method, and the film thickness varies depending on the application, but is formed in the range of about 100 Å to 10000 Å.

【0036】

In addition to the above, as a material constituting the OVD effect layer (34b), its refractive index is higher than that of the polymer material (refractive index n = 1.3 to 1.5) used in the OVD cambium (34a), and it is conductive. Any material other than the above-mentioned inorganic materials, such as an organic-based material, an organic-inorganic composite, or a material in which an inorganic-based filler is dispersed in an organic-based material, can be used. These materials are formed in an amount of about 0.1 μm to 10 μm by a known coating method such as gravure coating, die coating, screen printing, or a printing method. Furthermore, even if the material is other than the above, any material having reflexivity can be used as appropriate.

【0037】

On the other hand, the OVD layer (44) formed by the multilayer thin film method shown in FIG. 4 is composed of multilayer thin film layers (44a, 44b, 44c) having different optical characteristics as described above, and is composed of a metal thin film, a ceramic thin film, or a ceramic thin film. They are laminated and formed as a composite thin film formed by arranging them side by side. For example, when laminating thin films having different refractive indexes, thin films having a high refractive index and thin films having a low refractive index may be combined, or specific combinations may be laminated alternately. By combining them, a desired multilayer thin film can be obtained.

【0038】

A material such as ceramics or metal is used for this multilayer thin film layer, and a material having a high refractive index of about 2 or more and a material having a low refractive index having a refractive index of about 1.5 are laminated with a predetermined film thickness. An example of the material used below is given. First, as ceramics, Sb₂O₃(3.0 = refractive index n: same below), Fe₂O₃(2.7), TiO₂(2.6), CdS (2.6), CeO₂(2.3), ZnS (2.3), PbCl₂(2.3), CdO (2.2), Sb₂O₃(2.0), WO₃(2.0), SiO (2.0), Si₂O₃(2.5), In₂O₃(2.0), PbO (2.6), Ta₂O₃(2.4), ZnO (2.1), ZrO₂(2.0), MgO (1.6), SiO₂(1.5), MgF₂(1.4), CeF₃(1.6), CaF₂(1.3 ~ 1.4), AlF₃(1.6), Al₂O₃Examples thereof include (1.6) and GaO (1.7), and examples of the metal material include thin films having an island-like structure of a single metal or an alloy, such as Al, Sn, Sn-Al and the like.

【0039】

Further, organic polymers having a low refractive index, for example, polyethylene (1.51), polypropylene (1.49), polytetrafluoroethylene (1.35), polymethylmethacrylate (1.49), polystyrene (1.60) and the like can be used. By selecting at least one of these high-refractive-index materials or a metal thin film having an island-like structure having 30% to 60% permeability and at least one of low-refractive-index materials and alternately laminating them to a predetermined thickness, a specific material can be specified. It shows absorption or reflection of wavelengths of visible light. Since the optical properties such as the refractive index of the thin film made of metal change depending on the state of the constituent material and the formation conditions, the values under certain conditions are used in the examples of the present invention.

【0040】

Each of the above materials is appropriately selected based on optical characteristics such as refractive index, reflectance, and transmittance, weather resistance, chemical resistance, interlayer adhesion, and the like, and is laminated as a thin film to form a multilayer thin film. A known method can be used as the forming method, and the film thickness, film formation rate, number of layers, optical film thickness (= n · d, n: refractive index, d: film thickness) can be controlled, usually. A physical vapor deposition method such as a vacuum deposition method or a sputtering method, or a chemical vapor deposition method such as a CVD method can be used.

【0041】

Further, as a film forming method of a low refractive index organic polymer, a known printing method such as a gravure printing method, an offset printing method or a screen printing method, or a coating method such as a bar coating method, a gravure method or a roll coating method is used. be able to. Although only ceramics / metals are disclosed in the present invention, any ceramic / metal having a refractive index and reflectance equivalent to or similar to those of ceramics / metal can be used.

【0042】

To give a specific example of this multilayer thin film layer, the layer thickness is in the range of 50 to 20000 Å, and the layer structure of the thin film is a thin film made of the above-mentioned high refractive index material or metal material, for example, ZnS, TiO.₂, ZrO₂, In₂O₃, SnO, ITO, CeO₂, ZnO, Ta₂O₃, Al, Sn, etc., and a thin film made of the above-mentioned materials with a low refractive index, such as MgF.₂, SiO₂, CaF₂, MgO, Al₂O₃It is a combination with the above, and the layers are alternately laminated, and the number of layers is two or more, preferably 2 to 9 layers. It should be noted that the optical characteristics of the multilayer film differ depending on the material and combination used, and thus the present invention is not limited to this.

【0043】

The protective layers (16, 36, 46, 56) serve to protect the OVD layer and the printed layer from trauma and are formed as needed. Conventionally known resins such as acrylic resin, urethane resin, vinyl chloride resin-vinyl acetate copolymer resin, polyester resin, melamine resin, epoxy resin, polystyrene resin, and polyimide resin are used. A thermoplastic resin, a thermosetting resin, an ultraviolet ray or an electron beam curable resin may be used alone or in combination.

【0044】

Further, in order to prevent printing marks during image formation by a thermal head or the like, a curing agent for cross-linking the resin, waxes such as polyethylene washes, carnauba wax, silicon wax, or calcium carbonate, zinc stearate, silica, alumina, etc. Constituent pigments such as talc and oils and fats such as silicone oils and fats can be added as long as the transparency is not impaired. The resin used for the peeling protective layer is coated by, for example, a known coating means such as a gravure printing method, a screen printing method, or a nozzle coater method, and a printing means such as an offset printing method or a flexographic printing method.

【0045】

As the magnetic information recording medium as described above, the configuration in which the magnetic layer / matted concealing layer / OVD layer / printing layer / protective layer is laminated is an example, and is above each layer depending on the form of the product or the manufacturing method. It is possible to appropriately provide an adhesive layer or a printing layer on the surface. Further, the stacking order is not limited to this, and for example, a configuration in which a print layer is provided on the concealing layer or a configuration in which the OVD effect layer also serves as a concealing layer may be used. On the other hand, in order to improve the prevention of counterfeiting, it is possible to add a configuration in which a latent image is added with a fluorescent color ink, an infrared ink, a liquid crystal polymer, or the like.

【0046】

When producing such a magnetic information recording medium, the OVD transfer foil (50) shown in FIG. 5 may be used and transferred to the magnetic information recording medium base material via the adhesive layer (52). The OVD transfer foil is a protective layer (56), a printing layer (55), an OVD layer (54), a matted concealing layer (53), and an adhesive layer (adhesive layer) having peelability on the OVD transfer foil support (51). 52) is stacked. As these materials and production methods, those described above can be used. If this OVD transfer foil is transferred to a magnetic information recording medium base material via an adhesive layer, the above magnetic information recording medium can be easily produced.

【0047】

The surface for matting the concealing layer may be provided on either one or both of the front surface and the back surface in consideration of the layer structure.

【0048】

[Example]

The present invention will be described in detail with reference to specific examples.

【0049】

[Example 1] An embodiment of the magnetic information recording medium of the present invention shown in FIG. 3 will be described. First, a prototype was made using a card containing a magnetic tape in which a magnetic tape of 650 Oe was embedded as a magnetic layer (32) in a magnetic information recording medium base material (31) made of vinyl chloride having a thickness of 760 μm by thermal pressure. After 500 Å of Sn is vapor-deposited on the surface of the magnetic information recording medium base material (31) in an island-like structure to matte the surface, the OVD cambium (34a) having the following composition is 1 μm by the gravure method, and the OVD effect layer (34b). ) As TiO₂Was molded by vacuum deposition for 500 Å, and then a stamper of a relief rainbow hologram heated to 140 ° C. was pressed against it using a roll embossing method to form a rainbow hologram pattern. Furthermore, the pattern was printed with a size of about 1 μm. Then, 2 μm of an ultraviolet curable material having the following composition was applied as a protective layer (36), and the material was cured by irradiating with ultraviolet rays.

【0050】

<OVD cambium composition> 20 parts of polyester 5 parts of HMDI (hexamethylene diisocyanate) MEK (Methyl Ethyl Ketone) 50 parts 25 parts of toluene <Protective layer composition> Urethane acrylate 50 parts Acrylate Monoma-45 copies Photopolymerization initiator 5 parts [0051]

The magnetic card thus obtained had no visible magnetic layer and could be concealed with only 500 Å Sn vapor deposition. As for the magnetic output, a good output was obtained because the distance between the magnetic tape and the card surface was about 5.0 μm. Further, since the electric charge is not accumulated in the stacked state and the electricity is not discharged suddenly, the work is easy and no error occurs even if the magnetic information is written and read several tens of times.

【0052】

[Example 2] An embodiment of the magnetic information recording medium of the present invention shown in FIG. 4 will be described. The magnetic card of Example 2 was obtained in the same manner as in Example except that the OVD layer (44) was made into a multilayer thin film.

【0053】

As this multilayer foil thin film, ZnS-950Å, SiO₂-5800 Å and ZnS-950 Å were formed in this order to form the OVD layer (44).

【0054】

The magnetic card thus obtained had no visible magnetic layer and could be concealed with only 500 Å Sn vapor deposition. As for the magnetic output, a good output was obtained because the distance between the magnetic tape and the card surface was about 5.0 μm. Further, since the electric charge is not accumulated in the stacked state and the electricity is not discharged suddenly, the work is easy and no error occurs even if the magnetic information is written and read several tens of times. On the other hand, in this embodiment, since the OVD layer of the multilayer thin film is formed, a highly decorative card whose color changes depending on the viewing angle can be obtained.

【0055】

[Effect of the invention]

As described above, the magnetic information recording medium of the present invention has a sufficient magnetic output even though the OVD is formed by concealing the magnetic layer with a matted thin film that does not show conductivity. In addition to being obtained, it is possible to provide a medium that does not cause any trouble during handling or error during writing and reading of magnetic information. That is, the magnetic layer is not confirmed on the outside, it can be concealed, and since it does not accumulate electric charges in a stacked state and does not rapidly discharge static electricity, it is easy to work and when writing and reading magnetic information. It is a magnetic information recording medium that does not cause an error.

[Simple explanation of drawings]

[Figure 1]

An embodiment of the magnetic information recording medium of the present invention is shown, where (A) is a plan view and (B) is a cross-sectional view taken along the X-ray section.

[Figure 2]

It is a structural sectional view of the concealing layer transfer foil for making the matted concealing layer shown in FIG. 1 (B).

[Fig. 3]

It is an embodiment of the magnetic information recording medium of the present invention, and is a structural cross-sectional view when a relief type OVD is used.

[Fig. 4]

It is an embodiment of the magnetic information recording medium of the present invention, and is a structural cross-sectional view when a multilayer thin film type OVD is used.

[Fig. 5]

It is a structural sectional view of the OVD transfer foil.

[Fig. 6]

It is a conceptual diagram explaining the island-like structure of a concealment layer.

[Explanation of symbols]

10 ... Magnetic information recording medium 11 ... Magnetic information recording medium base material 12 ... magnetic layer 13 ... concealment layer 14 ... OVD layer 15 ... Print layer 16 ... protective layer 20 ... Concealment layer transfer foil 21 ... Concealment layer transfer foil support 22 ... Peeling layer 23 ... Concealment layer 24 ... Adhesive layer 30 ... Magnetic information recording medium 31 ... Magnetic information recording medium base material 32 ... magnetic layer 33 ... Concealment layer 34 ... OVD layer 34a ... OVD cambium 34b ... OVD effect layer 35 ... print layer 36 ... protective layer 40 ... Magnetic information recording medium 41 ... Magnetic information recording medium base material 42 ... magnetic layer 43 ... concealment layer 44 ... OVD layer 44a, 44b, 44c ... Thin film layer 45 ... Print layer 46 ... protective layer 50 ... OVD transfer foil 51 ... OVD transfer foil support 52 ... Adhesive layer 53 ... Concealment layer 54 ... OVD layer 55 ... Print layer 56 ... Peeling protection layer 60 ... concealment layer 61 ... Metal thin film (island)