JP2694768B2 - Reflective hologram sheet and reading method thereof - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a reflection hologram sheet, and more particularly, it is useful for decoration of various articles such as various cards, and forgery and unauthorized use of these decoration articles. The present invention relates to a reflective hologram sheet that can be made difficult or impossible and a method for reading information from the hologram sheet. (Prior Art) Conventionally, various kinds of holograms are known, and since these holograms have excellent information recording property (and reproducing property) and excellent three-dimensional aesthetics, they are used as various information recording media and decoration materials. Is being done. (Problems to be Solved by the Invention) Holograms are roughly classified into a transmission hologram for reading or observing transmitted diffracted light and a reflection hologram for reading or observing reflected diffracted light. Since the conventional transmission hologram is a method of reading or observing transmitted light, when used as a decorative material for various articles, it is necessary to provide a window opening in the article to be decorated, for example, a cash card or the like. Therefore, there is a defect that the decorative material lacks versatility. Further, in the information recording / reproducing, since the information reproducing light is the diffracted light that has been transmitted, it is necessary to install the collation light source and the device for reading the transmitted diffracted light on the opposite side of the article. There is a drawback that the reading device becomes large and complicated and is not suitable for a small vending machine or the like. On the other hand, in the case of a reflective hologram sheet, since the reflected diffracted light is read or observed, it is not necessary to form a window opening in the article to be decorated, and it can be easily attached to any article by sticking. Therefore, it is suitable as a decorative material and is widely used. Further, when these reflection type hologram sheets are embossed duplication type, recording of images and information, creation of embossed original plate, transfer duplication and the like require various expensive devices, but once the original plate is created It has the advantage of being capable of mass replication. Therefore, it is useful as a decoration material, and it is almost impossible for other people to create a hologram sheet on which the same image or information is recorded. It is also useful as a means of. However, in the case of these reflection type hologram sheets, the authenticity can be easily discriminated by the naked eye, but when used in places where human eyes are not used, such as vending machines, fraud prevention is possible. So far it has not been effective. Of course, it is theoretically possible to provide a vending machine or the like with a detection means for discriminating the authenticity of these hologram sheets, but in the case of a conventional hologram sheet for decoration, it is complicated and elaborate. Since such images and the like are recorded, the reading of the image requires an expensive and large-sized device, which is practically impossible. Therefore, there is a demand for a reflective hologram sheet which is useful as a decorative material for various articles and which can be easily discriminated from the naked eye by a simple device. (Means for Solving Problems) As a result of earnest research to meet the above-mentioned demands of the prior art, the present inventor found that a relatively simple specific information recording portion was formed in a conventionally known reflection hologram sheet for decoration. The present invention has been completed by finding that the above-mentioned drawbacks of the prior art can be easily solved by incorporating the above-mentioned techniques. That is, according to the present invention, a decoration image recording portion on which a naked eye-decorable decoration image developed by reflected diffracted light is recorded and at least one specific information recording portion are provided at positions where these recording portions do not overlap. At the same time, the specific information recording portion has a diffraction grating in which the intensity of the reflected diffracted light of the collation light beam of a specific angle with respect to the portion is greater than the intensity of the reflected light of the irregular reflection surface of the same collation light beam irradiated at the same angle. And a method for reading the same. (Preferred Embodiment) Next, the present invention will be described in more detail with reference to the accompanying drawings showing a preferred embodiment of the present invention. FIG. 1 is a diagram schematically showing a cross section of a reflection type hologram sheet 10 of one example of the present invention. The reflection type hologram sheet 10 of the present invention is a hologram sheet as shown in FIG. The main feature is to have an image recording portion A and at least one specific information recording portion B at the same time. That is, the decorative image recording portion A is a decorative image recording portion that can be discriminated as to whether it is for decoration or with the naked eye, like the conventional hologram sheet. However, it is not necessary to consider, for example, the simplicity of the authenticity determination device in the vending machine. On the other hand, in the specific information recording portion B incorporated in the decorative image recording portion A, a hologram diffraction grating composed of simple interference fringes is recorded as compared with the decorative image recording portion A, so that it can be easily performed by a simple reading device. It is designed to be read by. FIG. 2 is a reflection type hologram sheet 10 of the present invention shown in FIG.
The area A shows a decorative image recording portion, the area B shows a specific information recording portion, and interference fringes such as laser light are schematically shown by thin lines in these areas. There is. As described above, since the area A is the decorative image recording portion,
The recorded interference fringes are complex, and it is not easy to read the interference fringes with a simple device to determine the authenticity, but since the region B is a relatively simple interference fringe, it can be read with a simple device. is there. With the above configuration, it is possible to decorate the article by the area A and determine whether the article is authentic or not by the naked eye of the human, and the specific information recording portion B adjacent to the decoration image recording portion A allows, for example, automatic sale. The authenticity can be easily discriminated by a simple device such as a machine. The structure of the reflection type hologram sheet 10 of the present invention is not limited to that shown in FIGS. 1 and 2, but the specific information recording portion B is limited to an example in which both sides of the decorative image recording portion A as shown in FIGS. However, an example that exists around the decorative image recording portion A,
An example of being present on one side of the decorative image recording portion A, an example of being present in the decorative image recording portion A in an island shape, and a specific information recording portion B being 1
It includes any example such as a case where there are multiple places and a case where there are plural places. The reading method which is the second invention of the present invention is the specific information recording portion B of the reflection hologram sheet 10 of the present invention.
3 is a method for reading the information recorded in FIG. 3A, in which the specific information recording portion B of the reflection hologram sheet 10 of the present invention is irradiated with the matching light beam 6 at a specific angle as shown in FIG. The sensor 8 receives and reads the reflected diffracted light 7 diffracted by the hologram. The collation light beam 6 emitted from the collation light source 9 is diffracted and reflected by the specific information recording portion B and is reflected diffracted light of several orders, for example, 7a (0th order), 7b (first order), 7c (second order), 7d (third order). ) ...
Is reflected as A sensor 8 detects any diffracted light of the reflected diffracted light 7, for example, 7b (first-order diffracted light).
It is possible to discriminate whether the hologram sheet 10 is a genuine product or a counterfeit product by receiving the light and recording and collating the light intensity. However, as an example of the preferred embodiment, when the angle of the collation light beam 6 is constant, the angle and intensity of the diffracted reflected light 7b can be relatively easily confirmed by another person. By forming a diffused reflection surface having a reflectance as shown by the broken line in FIG. 3 instead of the specific information recording portion B, the sensor 8 causes the first-order diffracted light 7b.
Counterfeiting is relatively easy because it can receive reflected light in the same direction as. In order to prevent these, it is preferable to make a plurality of collations by using a plurality of collation light sources 9 and 9'of two or more places and changing their irradiation directions and angles. For example, since the reflected diffracted light 7b is received by the sensor 8 with a specific intensity in one collation light beam 6, it cannot be distinguished as irregular reflection light, but the other collation light beam 6 ', for example, does not generate diffracted reflection light (grating). Such a position and angle (when incident along a direction), that is, by utilizing the characteristics of the hologram, is not received by another sensor 8 ', while the diffusely reflected light is also detected by the sensor 8'. Since the light is received, it is possible to sufficiently counter the forgery due to the diffuse reflection. However, it is unavoidable that the use of the plurality of collation light sources 9, 9'and the plurality of sensors 8, 8'in this way makes the apparatus expensive and complicated. Therefore, in order to solve such a problem, the pitch of the diffraction grating of the hologram is devised so that the first-order one with the highest intensity among the reflected diffracted light of several orders (7a, 7b, 7c, 7d ...) It is preferable that the diffracted light (7b) is incident on the sensor 8 so that the intensity of the diffracted light (7b) is larger than that of the light reflected by any diffuse reflection surface. By doing so, it is possible to sufficiently counter forgery and unauthorized use that utilize the irregular reflection surface. In a further preferred embodiment, in order to further simplify the reading device, the collation light source 9 and the sensor 8 ″ are adjacent and integrated as shown in FIG. 3 (b), and the primary reflected diffracted light 7b is the collation light beam. It can be returned to the sensor 8 ″ in the vicinity of the source 9. That is, when the hologram of the specific information recording portion B is formed, the reflected diffracted light 7b becomes first-order diffracted light at such a position, and the pitch width of the diffraction grating of the specific information recording portion B is set so that the intensity becomes larger than the irregular reflection light. It is possible to simplify the device by changing the above, and to prevent forgery due to irregular reflection. Next, a method for forming the hologram sheet 10 of the present invention as described above will be described. Explaining the first illustrated example as a typical example, the hologram sheet 10 of the present invention is such that an adhesive layer 2 is first provided on the surface of a base material 1 if necessary, and further ultraviolet or electron having thermoformability is provided on the surface. A line-curable resin or a thermosetting resin 4 having thermoformability is provided to form a hologram forming layer. Among the above resins, an ultraviolet or electron beam curable resin that is solid at room temperature before curing and has thermoformability is particularly preferable. Next, the hologram forming layer 4 thus obtained and a hologram master plate (not shown) on which minute irregularities are formed are heated and pressure-contacted so that the forming layer 4 contacts the hologram master plate, and the minute irregularities are formed on the surface of the forming layer. While transferring, or after that, the resin is cured by irradiating ultraviolet rays or electron beams or by further applying heat. The hologram original plate may be a hologram original plate having the decorative image recording portion A and the specific information recording portion B at the same time as described above, or two or more hologram original plates having the recording portions separately may be arranged in parallel. Alternatively, the hologram sheet having the decorative image recording portion A and the hologram sheet having the specific information recording portion B may be separately prepared, and then the both may be arbitrarily combined and used. When the hologram original plate and the hologram forming layer are heated and pressed, a heating and pressing means such as a heating roll can be used. At this time, the temperature of the heating roll depends on the kind of resin to be used, the material of the base film 1, the thickness, etc. Although it varies greatly depending on the temperature, it is generally suitable that the temperature is 100 to 200 ° C. Further, it is preferable that the hologram original plate and the hologram forming layer are brought into pressure contact with each other under a pressure of 0.1 kg / cm ² or more, preferably 1 kg / cm ² or more. At this time, ultraviolet rays or electron beams may be irradiated. Further, the hologram forming layer 4 on which the minute irregularities of the hologram of the hologram master plate are transferred may be peeled from the hologram master plate and then irradiated again, and the irradiation intensity is preferably such that the resin is sufficiently cured. Irradiation with ultraviolet rays or electron beams needs to be appropriately determined according to the resin used. Next, a reflective metal thin film layer or hologram effect layer 3 is applied. This reflective metal thin film layer or hologram effect layer 3 can be provided on the hologram forming layer 4 by a sputtering method, an ion plating method, a vacuum deposition method, or another method. Further, a protective layer or the like (not shown) may be formed on the surface. The above is an example of the production of the hologram sheet 10 of the present invention, and the hologram sheet 10 of the present invention is not limited to the above example, and any other configuration as long as it has the decorative recording portion A and the specific image recording portion B at the same time. But it is good. For example, the fourth illustrated example is the hologram sheet of the present invention.
10 is an example of a transfer sheet type for ease of use, 11 is a peelable base material, 12 is a release layer / protective layer, 13 is a hologram forming layer, and 14 is a reflective metal thin film or hologram. 15 is an effect layer, and 15 is a heat-sensitive adhesive layer. If you use this type of hologram sheet, its layer 15
The hologram sheet is easily attached to the article to be decorated 20 by facing the article to be decorated 20 and heating to peel off the base material 11.
It can be pasted on. In addition, the example of FIG. 5 is an adhesive label type hologram sheet 10.
The base material 11 is transparent and can be directly attached to the article to be decorated 20. The "reflectivity" of the reflective hologram in the present invention means that the hologram image can be observed from the incident light side, and in addition to completely hiding the base, the hologram reflective layer 3 is a hologram effect layer. 3 and the difference in the refractive index between this layer and the hologram forming layer is 0.1 or more, preferably 1.0 or more, the hologram sheet becomes transparent so that the hologram image can be observed from the incident light side and the hologram sheet 10 is used as an article. It also includes those that can be seen such as the design of the underlying article when attached to 20. The article to be decorated by adhering the hologram sheet 10 of the present invention as described above is an article to which the decorative hologram sheet 10 is conventionally attached, and the article is not particularly limited, but for example, automatic sale Machines, automatic cash drawers at banks, prepaid cards such as those used at telephone boxes and ticket vending machines at stations, cards such as identification cards used at offices, bank passbooks, stock certificates, gift certificates, etc. Such as cash vouchers, etc. that are forged or misused,
Furthermore, it is particularly useful for decoration of expensive articles such as watches. The method for laminating the hologram sheet 10 of the present invention to the above various articles is not particularly limited, and for example, laminating and adhering by forming the adhesive layer 5 on the back surface of the hologram sheet 10 in advance as shown in FIG. Heat fusion bonding without agent, No. 4
As shown in the figure, any method such as a transfer method, a label method as shown in FIG. 5 and a laminating method may be used. (Operation / Effect) According to the present invention as described above, the decorative effect is great for various articles, and it is possible to distinguish between genuine articles and counterfeit articles even with a relatively simple device. A hologram sheet 10 is provided, and according to the method of the present invention, it is possible to easily realize the authenticity of the hologram sheet or the bonded article thereof. Next, the present invention will be described more specifically with reference to examples.
In addition, in the text, parts are based on weight. Example 1 A polyester film having a thickness of 50 μm as a substrate was coated with a composition for a protective layer / release layer having the following formulation by a gravure reverse method at a dry coating thickness of 0.5 μm to form a protective layer / release layer. Composition for forming protective layer / release layer Cellulose acetate resin 5 parts Methanol 25 parts Methyl ethyl ketone 45 parts Toluene 25 parts Methylolated melamine resin 0.5 parts Paratoluene sulfonic acid 0.05 parts Next, on the above protection layer / release layer, the following composition The ultraviolet-curable hologram forming composition of 1 was applied by a gravure reverse method at a dry coating thickness of 2 μm to form a hologram forming layer to obtain a hologram forming sheet. Ultraviolet curable hologram forming layer composition Acrylic resin 40 parts Melamine resin 10 parts Cyclohexanone 50 parts Methyl ethyl ketone 50 parts Next, an embossing mold for forming minute irregularities of a hologram was prepared in the following manner. First, a bird's three-dimensional object image was photographed and recorded as a rainbow hologram on a photosensitive substrate for photoresist, and then information recording portions consisting of diffraction gratings were recorded by multiple exposure on both ends of this three-dimensional object image. The recording of this information recording portion is performed by an optical system as shown in FIG. 6, and is emitted from the Ar laser source (488 nm) 32 to the normal line of the photoresist photosensitive substrate 31 and the half mirror 3
The two luminous fluxes 33, 33 'divided into 4 are divided by ±
Incident at an angle of 20 degrees and a diffraction grating pitch of 0.7 μm
Recorded. The object image of the bird obtained as described above is recorded by a rainbow hologram, and the information recording portion is recorded by a diffraction grating with a pitch of 0.7 μm. The hologram surface of the hologram original plate is plated to form a die for embossing. . Then, the hologram forming layer of the obtained hologram forming sheet is brought into contact with the embossing die and heated and pressed (temperature; 150 ° C., pressure; 10 kg / cm ² ) to form minute irregularities in the hologram forming layer. Immediately after that, the sheet is exposed to UV
The hologram forming layer was completely cured by passing through a position of 10 cm under a mercury lamp of 80 W / cm at a speed of 10 cm / min. Next, aluminum was vacuum-deposited to a thickness of 300 angstroms on the fine irregular surface to form a reflective metal thin film layer to obtain a hologram sheet of the present invention. Next, an adhesive composition having the following composition was applied on the reflective metal thin film layer by a gravure method so as to have a dry thickness of 5 μm to form an adhesive layer to prepare a hologram transfer sheet as shown in FIG. Adhesive layer composition Vinyl chloride / vinyl acetate copolymer 20 parts Acrylic resin 10 parts Ethyl acetate 20 parts Toluene 50 parts The adhesive layer surface of the next hologram transfer sheet and a polyester prepaid card with a thickness of 250 μm On the surface of both, and the temperature of 150 ℃, pressure 10kg /
Heat and pressure were applied for 1 to 3 seconds under the condition of cm ² , the base material of the transfer sheet was peeled off, and the hologram was transferred onto the corner of the card in a square size of 1 cm ² . The card was then read as follows. First, at the angle of 30 degrees with respect to the normal direction of the surface of the information recording part of the hologram of the obtained card with hologram,
The 660 nm collimated LED light source illuminates the diffraction grating of the information recording part of the hologram at right angles to the grating,
When the reflected diffracted light was measured by a photosensor provided adjacent to the light source at an angle of 28 degrees with respect to the normal direction, first-order diffracted light equivalent to 25% of the incident light could be detected. On the other hand, although the reflected light was detected by the same irradiation and reading device on the white diffuse reflection surface without the information recording part, the value was 10% of the incident light, and the difference between the reflected light intensity caused the difference between the genuine and fake products. I was able to make a distinction. The hologram of the object image of the bird for decoration between the information recording portions was reproduced well and was beautiful. Example 2 In the same manner as in Example 1, on a polyester film,
A protective layer / release layer was formed. Then, the composition for forming an electron beam-curable hologram having the following composition was applied on the protective layer / release layer by a gravure reverse method to a dry thickness of 2 μm, and then an electron beam having an intensity of 3 Mrad was irradiated to precure the hologram. A forming layer was formed. Electron beam-curable hologram forming composition Urethane acrylate resin 100 parts Irgagure 184 4 parts Methyl ethyl ketone 300 parts Next, aluminum was vapor-deposited on the pre-cured hologram-forming layer to a thickness of 300 Å by a vacuum vapor deposition method to form a reflective metal thin film. Layers were formed. Next, an embossing mold for forming minute irregularities of the hologram,
Two light fluxes from an Ar laser (488 nm) are incident relative to each other at an angle of ± 10 degrees, and the diffraction grating pitch is 1.4 μm.
It was made in the same manner as in Example 1 except that the above was formed. Next, in the same manner as in Example 1, after forming minute irregularities on the hologram forming layer, the hologram forming layer was completely cured by irradiation with an electron beam having an intensity of 175 KV and 10 Mrad to obtain the hologram sheet of the present invention. It was Next, an adhesive layer was formed in the same manner as in Example 1 to prepare a hologram transfer sheet as shown in FIG. Next, the surface of the adhesive layer of the obtained hologram transfer sheet and the surface of a vinyl chloride magnetic card having a thickness of 0.76 mm are overlapped with each other, and both of them are subjected to a temperature of 150 ° C. and a pressure of 10 kg / cm ² for 1 to 3 The base material of the transfer sheet was peeled off by heating and pressing for 2 seconds, and the hologram was transferred onto the corner of the card in a circle with a diameter of 1 cm. The card was then read as follows. First, at the angle of 25 degrees with respect to the normal direction of the surface of the information recording part of the hologram of the obtained card with hologram,
Irradiate two lights from two 660nm collimated LED light sources onto the diffraction grating of the information recording part of the hologram at right angles to and parallel to the grating, and adjoin each LED light source at an angle of 28 degrees with respect to the normal direction. When the reflected light was measured with the photo sensor provided in, the diffracted light that was incident at a right angle to the grating could detect the second-order diffracted light, which was 15% of the incident light. No reflected diffracted light of the incident light was detected. On the other hand, the reflected light was detected by the same irradiation and reading device on the hologram surface having no information recording portion.
The value detected by the two sensors was 10% of each incident light, and it was possible to discriminate between the real thing and the fake one by the difference in the reflected light intensity. The hologram of the object image of the bird for decoration between the information recording portions was reproduced well and was beautiful. Example 3 In the same manner as in Example 1, on a polyester film,
A hologram forming layer was formed to obtain a hologram forming sheet. Next, in the same manner as in Example 1, an embossing mold is prepared,
Using this, fine irregularities were formed on the hologram forming layer in the same manner as in Example 1. Next, Sb ₂ S ₃ was vapor-deposited to a thickness of 300 angstroms on the above-mentioned fine uneven surface by a vacuum vapor deposition method to form a hologram effect layer to obtain a transparent hologram sheet of the present invention. Next, in the same manner as in Example 1, an adhesive layer is formed and a fourth step is performed.
A hologram transfer sheet as shown in the drawing was prepared. Next, the surface of the adhesive layer of the obtained hologram transfer sheet and the surface of the stock certificate made of paper are overlapped, and both of them are heated at a temperature of 12
Heat and pressurize for 1 to 3 seconds under the conditions of 0 ° C and pressure of 10 kg / cm ² ,
The base material of the transfer sheet was peeled off, and the hologram was transferred onto one place around the stock certificate in a size of 1 × 2 cm. Next, when the information recording portion of the hologram of this stock certificate was read by the same method as in Example 1, the first-order diffracted light equivalent to 25% of the incident light of similar intensity could be detected. On the other hand, the reflected light was detected on the surface of the stock certificate without the hologram by the same method, but the value was 10% or less, and it was possible to distinguish the genuine article from the fake one by the difference in the reflection intensity. . Further, the company seal of the stock certificate in the portion where the hologram was provided could be confirmed through the hologram, and the hologram of the bird object image was well reproduced. Example 4 The same ultraviolet curable hologram forming composition as used in Example 1 was applied to a polyester film having a thickness of 50 μm as a substrate by a gravure reverse method at a dry application thickness of 2 μm to form a hologram forming layer to form a hologram. A forming sheet was obtained. Next, in the same manner as in Example 1, an embossing mold is prepared,
Using this, fine irregularities were formed on the hologram forming layer in the same manner as in Example 1. Next, a reflective metal thin film layer was formed on the above-mentioned minute uneven surface in the same manner as in Example 1 to obtain a hologram sheet of the present invention. Next, in the same manner as in Example 1, a pressure-sensitive adhesive layer was formed on the reflective metal thin film layer to prepare a hologram label as shown in FIG. Next, peel off the release paper of the obtained hologram label,
The surface of a paper bank passbook was overlaid, and both were pressed to bond the hologram in the shape of a heart mark. Next, when the information recording portion of the hologram of this bank passbook was read by the same method as in Example 1, the first-order diffracted light equivalent to 25% of the incident light of similar intensity could be detected. On the other hand, the reflected light was detected on the hologram surface without the information recording part by the same irradiation and reading method, but the value was 10% or less, and the difference between the reflected light intensities was used to distinguish the genuine product from the fake product. I was able to. The hologram of the object image of a bird for decoration between the information recording portions was reproduced well and was beautiful.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1, FIG. 4 and FIG. 5 are diagrams schematically showing a cross section of a hologram sheet of the present invention, and FIG. 2 is a diagram schematically showing the plane of FIG. FIG. 3 is a diagram schematically showing the method of the present invention, and FIG. 6 is a diagram schematically showing a hologram photographing method. 1,11: Substrate 2,5,15: Adhesive layer 3,14: Reflective metal layer / hologram effect layer 4,13: Hologram forming layer 6,6 ′: Collation light 7: Reflected diffracted light 8,8 ′ , 8 ″: Sensor 9,9 ′: Light source 10: Hologram sheet 20: Decorative article A: Decorative image recording part B: Information recording part

Claims (1)

(57) [Claims] A decoration image recording portion on which a decoration image which can be distinguished by the naked eye and which is expressed by reflected diffracted light is recorded;
The specific information recording portions are simultaneously provided in positions where these recording portions do not overlap each other, and the specific information recording portions are irradiated with the intensity of the reflected diffracted light of the collation light beam at the specific angle with respect to the portions at the same angle. A reflection-type hologram sheet characterized by comprising a diffraction grating whose intensity is higher than that of the diffused reflection surface of the same collation ray. 2. The reflection type hologram sheet according to claim (1), which is an embossed duplication type. 3. A decoration image recording portion on which a decoration image which can be distinguished by the naked eye and which is expressed by reflected diffracted light is recorded;
The specific information recording portions are simultaneously provided in positions where these recording portions do not overlap each other, and the specific information recording portions are irradiated with the intensity of the reflected diffracted light of the collation light beam at the specific angle with respect to the portions at the same angle. The specific information recording portion of the reflection hologram sheet composed of a diffraction grating having a higher intensity than the diffused reflection surface of the same matching light ray is irradiated with one or more specific matching rays at a specific angle, The method for reading a reflection hologram sheet as described above, which comprises reading the reflected diffracted light diffracted by. 4. The reading method according to claim (3), wherein the hologram sheet is an embossed duplication type. 5. The reading method according to claim (3), wherein the verification light rays are a plurality of light rays emitted from a plurality of angles. 6. The reading method according to claim (3), wherein the collation light beam is one light beam emitted from one angle. 7. The reading method according to claim (3), wherein the collation light source section and the reflected diffraction light sensor are provided in substantially the same direction.