JP2921084B2 - Electric discharge breakdown recording media - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial application field> The present invention relates to a discharge breakdown recording medium, and more particularly to a discharge breakdown of a hologram-forming resin layer due to the appearance of a visible hologram image in an underlying layer by discharge. The present invention relates to a discharge breakdown recording medium, which can be recorded by the following method.

<Related Art> In recent years, for the convenience of card owners, information that can be viewed (hereinafter referred to as visible information) has been recorded on a card surface. In particular, regarding a prepaid card having a magnetic recording layer, the same value information as that of magnetic recording can be visually recognized without using a reader.

As a method of visualizing the value information, a method using a thermosensitive coloring layer has been conventionally adopted, but the conventional thermosensitive recording layer using the thermosensitive coloring action is visible on a magnetic recording medium having a magnetic recording layer. As a means for recording on the magnetic recording layer, a method of providing the recording medium on a substrate opposite to the magnetic recording layer or a method of providing the recording medium on a portion not overlapping the magnetic recording layer has been adopted. Therefore, when the magnetic recording layer surface occupies a large area, characters as visible information,
When pre-printing a picture or the like is performed and visible information is recorded later by a thermal head or the like, there is a disadvantage that a recording space is restricted.

Therefore, there has been proposed a thermosensitive magnetic recording medium in which a thermosensitive recording layer is directly formed on a magnetic recording layer as described in JP-A-52-114333 and JP-A-59-199285.

<Problems to be Solved by the Invention> However, the above-mentioned visual information is merely intended to make the remaining amount information visible, and does not have security itself. In addition, most of the information that can be handled by the above method is single-color character information, and it is almost impossible to provide multi-color image information, particularly three-dimensional image information such as a hologram image.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems. A hologram-forming resin layer is provided on a substrate, and two metal-based thin film layers are provided on the hologram-forming resin layer. An object of the present invention is to provide a discharge breakdown recording medium in which three-dimensional image information of an image appears.

<Means for Solving the Problems> According to an aspect of the present invention, there is provided a hologram-forming resin layer, a first metal-based thin film layer, an intermediate resin layer, and a second metal-based thin film. This is a discharge breakdown recording medium in which layers are sequentially laminated.

<Operation> According to the present invention, it is possible to provide a discharge breakdown recording medium in which three-dimensional image information of a hologram image appears by discharge breakdown recording.

<Detailed Description of the Invention> FIG. 1 is a partially enlarged cross-sectional view of a discharge breakdown recording medium (1) of the present invention, wherein at least a hologram forming resin layer (3) and a first metal-based thin film layer are formed on a substrate (2). (4) An intermediate resin layer (5) and a second metal-based thin film layer (6) are formed. A protective layer (7) for protecting the second metal-based thin film layer (6) may be provided as needed. If necessary, a magnetic recording layer can be provided on a part or the entire surface of the base (2). Further, if necessary, each layer can be formed via an adhesive.

As the substrate (2), plastics such as polyvinyl chloride, polyester, polycarbonate, polymethyl methacrylate, and polystyrene, paper, synthetic paper, and the like can be used alone or as a composite. The substrate (2) has physical properties required according to the use of the recording medium, such as a card or a sheet.
For example, it is possible to select from the above materials in consideration of the strength, rigidity, concealing property, light opacity and the like. When a magnetic recording layer is provided, for example, γ-Fe ₂ O ₃ , Co-coated γ-Fe ₂ O ₃ , Fe
₃ O ₄ , CrO ₂ , Fe, Fe-Cr, Fe-Co, Co-Cr, Co-Ni, MnA
l, a magnetic paint composed of a magnetic fine particle dispersion such as Ba ferrite and Sr ferrite is applied and provided. Generally, the coercive force of a magnetic recording layer used for a magnetic recording medium such as a prepaid card is 300 to 3000 (Oe), and the residual magnetic flux is 1.0 to 2.0 (Maxwell
/ cm).

The hologram-forming resin layer (3) is made of, for example, an acrylic resin, a urethane resin, a cellulose acetate resin, a nitrocellulose resin, or the like, and has a thickness of 0.5 to 4 μm. When a hologram image of this layer is formed, when the hologram is a relief hologram that records hologram information by surface irregularities, a hologram master in which interference fringes are recorded in the form of irregularities is used as a press mold, and the above-described resin is used. It is formed by heating and pressing the layer surface. Examples of the hologram include a Fraunhofer hologram, a rainbow hologram, and a holographic stereogram.

The first metal-based thin film layer (4) is, for example, a vapor-deposited layer having a nonmagnetic metal thickness of about 0.03 to 0.1 μm, and is specifically made of aluminum, tin, or the like. As a forming method, a vacuum deposition method, a sputtering method, an ion plating method, or the like is employed. The intermediate resin layer (5) includes, for example, an acrylic resin, a urethane resin, a cellulose acetate resin,
A nitrocellulose-based resin or the like is formed into an ink and applied to form a film having a thickness of 0.5 to 4 μm.

The metal forming the second metal-based thin film layer (6) may be the same as that of the first metal-based thin film layer (4), and is made of aluminum or the like which can be destroyed by electric discharge. This layer is formed by a vacuum deposition method, a sputtering method, an ion plating method, or the like, and has a thickness of 0.03 to 0.1 μm.

Further, a protective layer (7) may be provided for the purpose of protecting the second metal-based thin film layer (6). The protective layer (7) may be formed by selecting an appropriate one of the above resins, forming an ink, and coating.

A lubricant may be further added to the protective layer (7) for the purpose of improving discharge recording suitability.

<Examples> Examples of the present invention will be described below. In addition, "part" in each Example shows a weight part.

<Example 1> On a 188 µm thick white PET sheet, a urethane-based resin was applied to a thickness of 2 µm by a gravure coating method to form a hologram-forming resin layer. Next, after the hologram-forming resin layer was dried and cured, the layer was subjected to an embossing treatment with a hologram stamper at 150 ° C. to form a hologram image. Next, on the hologram-forming resin layer on which the hologram image was formed, aluminum was deposited by a vacuum deposition method to a thickness of 0.05 μm to form a first metal deposition layer.
Next, an acrylic resin is applied to a thickness of 2 μm, and aluminum is deposited thereon to a thickness of 0.05 μm by a vacuum evaporation method to form an intermediate resin layer and a second metal evaporation layer to obtain a discharge breakdown recording medium. Was.

In this discharge breakdown recording medium, the hologram could be completely concealed by the second metal deposition layer. Further, when a discharge voltage of −30 V was applied to this recording medium, the second metal deposition layer was destroyed, and the image information of the hologram concealed under the second metal deposition layer could appear.

<Example 2> (1) Composition of coating liquid for conductive intermediate resin layer Acrylic modified resin 10 parts Curing agent 3 parts Toluene 5 parts MIBK (methyl isobutyl ketone) 5 parts Silver powder 1 part On a 188 μm thick white PET sheet Then, a black colored layer was formed by applying a mixture of carbon chloride and a vinyl chloride-nitrocellulose binder. Next, a urethane-based resin is applied to a thickness of 2 μm by a gravure coating method,
A hologram-forming resin layer was obtained. After this was dried and cured, a hologram image was formed on the hologram-forming resin layer by embossing using a hologram stamper at 150 ° C. Next, aluminum was deposited by a vacuum deposition method to a thickness of 0.05 μm to form a first metal deposition layer. Next, the coating liquid for the conductive intermediate resin layer having the composition (1) is applied to a thickness of 2
It was applied with a thickness of μm to form a conductive intermediate resin layer. Aluminum was evaporated thereon to a thickness of 0.05 μm by a vacuum evaporation method to form a second metal evaporation layer, thereby obtaining a discharge breakdown recording medium.

This discharge breakdown recording medium was able to completely hide the hologram by forming the second metal deposition layer. When a discharge voltage of −30 V was applied to this recording medium, the second metal deposition layer was destroyed, and image information of the hologram concealed in the lower layer could appear. Furthermore, the conductive intermediate resin layer and the first metal deposition layer were destroyed by the discharge of an applied voltage of −50 V, and information could be recorded by the appearance of the colored layer formed on the PET sheet.

Example 3 A 188 μm-thick white PET sheet was coated with a urethane-based resin mixed with carbon black to a thickness of 2 μm by a gravure coating method to form a colored hologram-forming resin layer. After drying and curing, a hologram image was formed on the colored hologram-forming resin layer by embossing at 150 ° C. using a hologram stamper. Next, aluminum is deposited by a vacuum deposition method to a thickness of 0.05 μm,
A first metal deposition layer was formed. Next, the coating liquid for the conductive intermediate resin layer having the composition described in Example 2 was applied to a thickness of 2 μm.
To form a conductive intermediate resin layer. Aluminum is deposited thereon by vacuum evaporation to a thickness of 0.05 μm,
A second metal vapor-deposited layer was formed to obtain a discharge breakdown recording medium.

This discharge breakdown recording medium was able to completely hide the hologram by forming the second metal deposition layer. When the recording medium was discharged at an applied voltage of −30 V, the second metal deposition layer was destroyed, and the image information of the hologram concealed in the lower layer could appear. Further, the conductive intermediate resin layer and the first metal deposition layer were destroyed by the discharge of the applied voltage of −50 V, and information could be recorded by the appearance of the colored hologram-forming resin layer.

<Effects of the Invention> As described above, the discharge breakdown recording medium according to the present invention can completely hide the hologram by forming the second metal vapor deposition layer, and the recording can be completed by discharging the hologram. It is possible. At this time, image information of the hologram concealed in the lower layer can be made to appear by discharge breakdown at a small voltage, and information can be recorded by discharge breakdown at a high voltage. Furthermore, it is possible to prevent forgery as well as to improve the decorativeness, and it becomes extremely easy to identify the recording medium.

[Brief description of the drawings]

FIG. 1 is a partially enlarged sectional view showing the structure of a discharge breakdown recording medium according to the present invention. (1) Discharge breakdown recording medium (2) Base (3) Hologram forming resin layer (4) First metal-based thin film layer (5) Intermediate resin layer (6) Metal thin film layer 2 (7) Protective layer

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B41M 5/24 G03H 1/02

Claims (4)

(57) [Claims] 1. A discharge breakdown recording medium comprising a hologram-forming resin layer, a first metal-based thin film layer, an intermediate resin layer, and a second metal-based thin film layer sequentially laminated on at least a substrate. 2. The discharge breakdown recording medium according to claim 2, wherein the intermediate resin layer has conductivity. 3. The discharge breakdown recording medium according to claim 1, wherein a colored layer is provided between the hologram forming resin layer and the substrate. 4. The discharge breakdown recording medium according to claim 1, wherein the hologram-forming resin layer is colored.