JPH06270568A - Image display element and thermal transfer sheet used in production thereof - Google Patents

Abstract

PURPOSE:To provide an image display element adapted to an ID card and capable of preventing the forgery and alteration thereof and the thermal transfer sheet used in the production thereof. CONSTITUTION:The principal part of a thermal transfer sheet is constituted of a base sheet 1, the release layer 2 provided thereon, a data pattern 3 containing an infrared absorbing substance and the image receiving adhesive layer 4 provided on the entire surface of the base sheet and having an image pattern 5 formed thereon by a sublimation transfer means and an image display element is formed by transferring the respective layers excepting the base sheet of the thermal transfer sheet on a card base material 6. Since the data pattern 3 containing the infrared absorbing substance and capable of being mechanically read by infrared rays is provided to the image display element in addition to image pattern 5 looked by the naked eye, forgery/alteration is made hard and, since the genuinness is also judged by mechanical reading in addition to the judgment due to the naked eye even when forgery/alteration is performed, the fact of forgery/alteration can be more certainly discovered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display body which is provided with an image pattern or a hologram image formed by sublimation transfer means based on image data, and is applied to, for example, an ID card or the like. The present invention relates to an improvement in an image display body capable of effectively preventing the above and a thermal transfer sheet used for manufacturing the image display body.

[0002]

2. Description of the Related Art FIG.
As shown in FIG. 3A, an image pattern s formed by sublimation transfer means based on image data is provided on a card base material r such as polyvinyl chloride, or as shown in FIG. In addition to s, a hologram image t is known.

A method for manufacturing the latter image display body having the hologram image by the thermal transfer method will be briefly described below.

First, as shown in FIG. 5 (A), a thermal transfer sheet a used for manufacturing this image display body is a heat resistant base sheet b made of polyethylene terephthalate or the like,
A release layer c made of thermoplastic acrylic resin or the like provided on the heat-resistant base sheet b, a hologram forming layer d having an uneven pattern provided on the release layer c, and provided along the uneven surface. A transparent thin film layer e made of a material having a refractive index larger than that of the hologram forming layer, and a transparent sublimable (heat transferable) dye provided on the transparent thin film layer e and heat-treated with respect to the base material of the image display body. An image receiving / adhesive layer f made of a resin material having an adhesive property constitutes a main part thereof.

Then, as shown in FIG. 4, this thermal transfer sheet a is conveyed to a sublimation transfer device j whose main portion is composed of a drum h and a thermal head i, and a transfer ribbon k whose coloring material is a sublimable dye. The dye layer (not shown) is brought into contact with the image receiving / adhesive layer f of the thermal transfer sheet a, and the transfer ribbon k
The thermal head i is pressed from the side and a heating element group (not shown) of the thermal head i is appropriately heated based on the image data to form an image pattern based on the image data on the image receiving / adhesive layer f. (See Figure 5B). still,
When the image data is multicolored, transfer ribbons having different color tones are applied and the same steps are repeated to form a multicolored image pattern on the image receiving / adhesive layer f.

Next, the image receiving / adhesive layer f of the thermal transfer sheet a on which the image pattern is formed is brought into contact with the base material m of the image display body (see FIG. 5C), and the thermal transfer sheet a is heated from the side of the thermal roll, An image display body p such as an ID card is manufactured by pressing and heating a heating medium n such as a heating plate to press the image receiving / adhesive layer f onto the base material m and peeling the heat resistant base sheet b from the thermal transfer sheet a. (See FIG. 5D).

[0007]

By the way, when this image display body is applied to ID cards such as credit cards and members' cards, the image pattern or hologram image on the image display body is not a pattern visually recognized by the naked eye. Therefore, there is a problem that it is easy to be forged / altered by replacing a face photograph or a hologram pattern, and it is difficult to visually confirm the fact of the forgery / alteration.

The present invention has been made by paying attention to such a problem, and an object thereof is to improve an image display body which can effectively prevent forgery and alteration and to apply it to the production of this image display body. To provide a thermal transfer sheet.

[0009]

That is, the invention according to claim 1 is premised on an image display body provided with an image receiving layer having an image pattern formed by sublimation transfer means based on image data on a base material, and the above-mentioned base is provided. An information pattern containing an infrared absorbing substance is formed on at least one surface of a material and an image receiving layer, while the invention according to claim 2 is an uneven pattern forming a relief hologram. Formed by a sublimation transfer means based on image data, which is provided adjacent to the transparent thin film layer and a transparent thin film layer provided along the uneven surface and having a refractive index higher than that of the hologram forming layer. An image receiving layer having an image pattern formed on the substrate is provided, and the image pattern is recognized together with the hologram image through the hologram forming layer and the transparent thin film layer. Based on the image display body described above, the hologram forming layer, the transparent thin film layer, the image receiving layer, and an information pattern containing an infrared absorbing substance are formed on at least one surface of the substrate. .

In addition, in the image display device according to claims 1 and 2, in addition to the image pattern and the hologram image visually observed with the naked eye, an information pattern containing an infrared absorbing substance and capable of being mechanically read by infrared rays. For that reason, it becomes difficult for counterfeiting / alteration to be made correspondingly, and even if forgery / alteration is made, authenticity determination by mechanical reading is made in addition to the genuineness determination by the naked eye.
As a result, it becomes possible to more reliably discover the fact of forgery and alteration.

In the inventions according to claims 1 and 2, the information pattern containing the infrared absorbing substance includes the infrared absorbing substance, a binder resin such as vinyl acetate vinyl resin, saturated polyester and polyurethane elastomer, and toluene and methyl. Isobutyl ketone, xylene, cyclohexanol, isobutyl acetate, cyclohexanone, methylcyclohexanone, glycol derivatives such as ethylene glycol monobutyl ether or the like or an infrared absorbing ink mainly containing a mixed solvent thereof, for example, a barcode, a two-dimensional code, It is formed by printing in an arbitrary pattern such as letters, numbers and figures.

Examples of the infrared absorbing substance include glass-based materials such as phosphate glass and sulfate glass, which are obtained by crushing infrared absorbing glass or heat ray absorbing glass having a small absorption in the visible region and converting it into a pigment.

The invention according to claim 3 applies a glass-based powder material containing Fe ²⁺ and / or Cu ²⁺ as an infrared absorbing substance.

That is, the invention according to claim 3 is claim 1
On the premise of the image display body according to any one of 1 to 3, the infrared absorbing substance is characterized by being composed of a glass-based powder material containing Fe ²⁺ and / or Cu ²⁺ .

More specifically, this glass-based powder material is a powder material containing phosphorus pentoxide (P ₂ O ₅ ) as a main component and containing iron oxide and / or copper oxide in an amount of 1.0% by weight or more.
More preferably, phosphorus pentoxide is 35.0 to 8% by weight.
It is characterized by being a glass-based powder material containing 0.0% of iron oxide and copper oxide of 0 to 3.0% respectively.

If necessary, the glass-based powder material may contain the following compounds. That is, Al ₂ O ₃ 2.0 to 10.0 wt% B ₂ O ₃ 1.0 to 30.0 wt% MgO 3.0 to 10.0 wt% ZnO 0 to 3.0 wt% K ₂ O 0 ˜15.0 wt% BaO 0-10.0 wt% SrO 0-1.0 wt% Ni, Co, Se Trace amount Also, it has less absorption in the visible region than the powdered glass-based material and has an infrared absorption capability. The following white crystalline materials such as white crystalline phosphate and white crystalline crystalline sulfate which are excellent can also be applied as the infrared absorbing substance.

When such a material is applied, its infrared absorbing ability is excellent, so that the mixing ratio of the infrared absorbing substance dispersed in the infrared absorbing ink forming the above information pattern can be reduced and the above base material can be used. The white type has an advantage of making it difficult to visually inspect the information pattern with the naked eye. The invention according to claim 4 is based on such a technical reason.

That is, the invention according to claim 4 is claim 1
On the premise of the image display according to any one of 1 to 3, the infrared absorbing substance is composed of a phosphate-based white crystalline powder material containing Fe ²⁺ and / or Cu ²⁺ and containing phosphorus pentoxide as a main component. It is characterized by that.

In the invention according to claim 4, the phosphate white crystal powder constituting the infrared absorbing substance contains 20 wt% or more of Fe ²⁺ and / or Cu ^2+, and phosphorus pentoxide (P ₂
O ₅ ) as a crystalline powder, preferably 40 to 70% by weight of phosphorus pentoxide, Fe ²⁺ and / or Cu ²⁺
A crystalline powder containing 30 to 70% of each is desirable.

The phosphoric acid white crystalline powder is
A phosphate-based composition having the above-mentioned composition is melted and crystallized to obtain a phosphate-based white crystal, and this is powdered. The phosphate-based white crystalline powder may also contain the following compounds, if necessary.

Al ₂ O ₃ 2.0 to 10.0 wt% B ₂ O ₃ 1.0 to 30.0 wt% MgO 3.0 to 10.0 wt% ZnO 0 to 3.0 wt% K ₂ O 0 to 15.0% by weight BaO 0 to 10.0% by weight SrO 0 to 1.0% by weight Ni, Co, Se Trace amount The invention according to claim 5 is the same technology as the invention according to claim 4 above. Claims 1 to 3
On the premise of the image display body according to item 2, the infrared absorbing material is characterized by being constituted by a white reaction product of tungsten hexachloride and phosphoric acid ester and / or phosphorous acid.

Here, in the image display device according to any one of claims 3 to 5, since the infrared absorbing material applied is white or lightly colored, it is suitable for applications where a white or lightly colored base material is used. Suitable, but when applied to a substrate that requires a color other than this, cyanine-based, phthalocyanine-based, dithiol metal complex salt-based, naphthoquinone-based, anthraquinone-based, which also has light absorption in the visible region
Infrared absorbing dyes such as triphenylmethane type, aminium type and diimmonium type can also be applied.

Next, the inventions according to claims 6 to 10 relate to a thermal transfer sheet applied when the image display according to claims 1 to 5 is manufactured by a thermal transfer method.

That is, the invention according to claim 6 is the invention according to claim 1.
Assuming a thermal transfer sheet used when manufacturing the image display body described by a thermal transfer method, a heat resistant base sheet,
A peeling layer provided on the base sheet in a peelable manner,
An image pattern is formed on the release layer by sublimation transfer means based on image data, and an image receiving / adhesive layer having thermal adhesiveness to the base material of the image display is provided, and the release layer and An information pattern containing an infrared absorbing substance is provided between the image receiving / adhesive layer, and the invention according to claim 7 manufactures the image display according to claim 2 by a thermal transfer method. A heat-resistant base sheet, a heat-resistant base sheet, a release layer provided on the base sheet in a peelable manner, a hologram forming layer having an uneven pattern provided on the release layer, and the above-mentioned unevenness. An image pattern is formed by a transparent thin film layer provided along the surface and having a refractive index larger than that of the hologram forming layer, and a sublimation transfer means provided on the transparent thin film layer based on image data. And an image receiving / adhesive layer having thermal adhesiveness to the base material of the image display, and the peeling layer and the hologram forming layer, the hologram forming layer and the transparent thin film layer, and the transparent thin film layer and the image receiving layer. An information pattern containing an infrared absorbing substance is provided on at least a part of the adhesive layer.

In the invention according to claims 6 to 7,
Examples of the heat-resistant base sheet include a biaxially stretched polyethylene terephthalate film and a polyethylene naphthalate film, which have heat resistance such that they are not softened and deformed by the heat pressure during transfer.

The release layer formed on the base sheet is easily released from the base sheet when the image-receiving / adhesive layer is thermally transferred to the base material of the image display body, and the transferred image-receiving / adhesive layer is transferred. It is necessary for the hologram forming layer to have a function of a protective film for preventing chemical or mechanical damage from the outside. To provide both functions, a mixture of thermoplastic resin and anti-friction agent is applied.

The thermoplastic resin prevents permeation of plasticizers and chemicals and reduces scratches due to scratching. As such a thermoplastic resin, polymethylmethacrylate or epoxy resin can be applied. Among existing thermoplastic resins, polymethylmethacrylate and epoxy resin have excellent plasticizer resistance and are substances that are easily peeled from the base sheet. By applying these resin materials, it is possible to prevent the migration of the plasticizer contained in the soft vinyl chloride sheet or the plastic eraser when they are brought into contact with the transferred image. Further, it becomes possible to prevent penetration of chemicals such as acids, alkalis, alcohols, and kerosene, and prevent the influence on the image.

Further, the anti-friction agent is added to improve wear resistance and scratch resistance. Examples of the anti-friction agent include Teflon powder, polyethylene powder, animal wax, plant wax, mineral wax, natural wax such as petroleum wax, synthetic hydrocarbon wax, aliphatic alcohol and acid wax, and fatty acid. Ester and glycerite wax, hydrogenated wax, synthetic ketone wax, amine and amide wax, chlorinated hydrocarbon wax, synthetic animal wax wax, synthetic wax such as alpha-olefin wax, and zinc stearate, etc. Examples thereof include metal salts of higher fatty acids.

The mixing ratio of the thermoplastic resin to the anti-friction agent is 85 to 95 parts by weight of the thermoplastic resin and 100% by weight of the total amount of the thermoplastic resin and anti-friction agent. It is set in the range of 5 to 15 parts by weight. The coating amount is set to about 1 to 3 g / m ² .

In addition to the above components, the release layer may contain a release improving agent such as a linear saturated polyester resin which improves the cuttability during thermal transfer. However, it is desirable to set this mixing ratio to about 0 to 3 parts by weight based on 100 parts by weight of the total amount of the thermoplastic resin and the anti-friction agent. Further, it is desirable not to add other additives such as an ultraviolet absorber to the release layer. This is because the addition of these causes a decrease in chemical resistance, or facilitates the penetration of a plasticizer to deteriorate the mechanical strength of the release layer.

In the method of coating the release layer, first, the composition of the release layer is made into a coating material with a suitable solvent, and the coating material is applied by gravure coating, roll coating, bar code coating, or the like. Thus, it can be formed by coating and drying on the heat resistant base sheet.

Next, in the thermal transfer sheet according to the seventh aspect, a hologram forming layer having an uneven pattern formed by a surface relief hologram stamper is provided on the release layer. Very good results can be obtained by using a two-component reaction type urethane resin as the resin material applied to the hologram forming layer. That is, the two-component reaction type urethane resin has good embossing moldability, press unevenness is less likely to occur, and a bright reproduced image is obtained, and also adhesiveness to the transparent thin film layer is good.

Such a two-component reactive urethane resin is a prepolymer having an isocyanate group and a polyol component such as polyether polyol, polyester polyol, acrylic polyol, etc. in view of various physical properties such as solvent resistance, heat resistance and processability. A polyol-curable urethane resin consisting of and is suitable. Among them, the polyol component has a glass transition point of 70.
By applying an acrylic polyol resin having a OH group in the range of ˜105 ° C. and an OH group in the range of 50 to 150, the coating suitability is good and the embossing moldability required for the thermal transfer sheet and the peeling from the heat resistant base sheet. It is possible to obtain a thermal transfer sheet having excellent properties. The above-mentioned isocyanate component includes toluene diisocyanate (TDI),
Xylene diisocyanate (XDI), hexamethylene isocyanate (HMDI), etc. can be applied.

As a modifier for improving coating suitability and transferability, a cellulose resin such as nitrocellulose, acetylcellulose, cellulose acetate butyrate, cellulose acetate propionate, ethyl cellulose or methyl cellulose is used as the above two-component reaction type urethane. You may add up to 30 weight% with respect to resin.

In order to apply such a hologram forming layer, a resin which has been made into a paint can be applied and dried by a method such as roll coating or blade coating, and the film thickness thereof is 0.5 to 5 μm. It is set to a degree.

The hologram-forming layer thus formed has a proper adhesion to the heat-resistant base sheet coated with the release layer, and has excellent formability by heating and pressurizing during embossing and has a surface. It does not show adhesiveness to a surface relief hologram stamper plated with nickel, gold, chrome, etc., and also shows good adhesiveness to a transparent thin film layer, and it is possible to form a film required for transfer to a substrate. Good cutting performance.

Next, as a material forming the transparent thin film layer, a material having a higher refractive index than the hologram forming layer and a high transmittance in the visible light region is used. When a transparent thin film layer having a high refractive index is provided along the concave-convex surface of the hologram forming layer, reflection of light on the transparent thin film layer is possible within the reproducible angle range of the hologram image due to the angle dependence of reproduction which is a characteristic of the hologram. This is because the ratio is maximized and functions as a "reflection hologram", while it functions as a mere transparent body outside the reproducible angle range of the hologram image, allowing the image pattern on the transferred body side to be seen through.

As the material constituting such a transparent thin film layer, the inorganic materials shown in Table 1 below can be exemplified.

[0039]

[Table 1] As a method of forming the transparent thin film layer, a film forming means such as a vacuum vapor deposition method, a sputtering method, an ion plating method or the like can be applied, and the film thickness thereof is appropriately in the range of 100 Å to 10000 Å. .

Next, in the thermal transfer sheet according to the sixth aspect, the image receiving / adhesive layer provided on the release layer, and on the transparent thin film layer in the thermal transfer sheet according to the seventh aspect is formed by the sublimation transfer means. It is a film made of a thermoplastic resin having an image pattern and having thermal adhesiveness to the base material of the image display body, and constitutes a part of the image display body by being thermally transferred to the base material.

When the thermal melting temperature of the thermoplastic resin is low, a part of the image receiving / adhesive layer is transferred to the transfer ribbon side when an image pattern is formed using a transfer ribbon whose colorant is a sublimable dye ( There is a risk of heat fusion. In order to prevent the transfer to the transfer ribbon, it is conceivable to apply a thermoplastic resin having a high heat melting temperature as the image receiving / adhesive layer. In the thermal transfer process of the image receiving / adhesive layer to the transfer target, a heat roll or a heat plate is used. Since it is necessary to raise the temperature setting of the isothermal heating medium, there is a problem that the image pattern made of the sublimable dye is deteriorated (discolored) and the base material is damaged by heat. It is also conceivable to add an additive such as silicon to the image receiving / adhesive layer in order to reduce the adhesiveness of the image receiving / adhesive layer to the transfer ribbon. It causes problems that get worse.

In order to solve such a problem, it is desirable that the image receiving / adhesive layer is composed of a thermoplastic resin having a glass transition point of 50 ° C. or higher and a filler added to the thermoplastic resin.

As described above, the thermoplastic resin applied to the image receiving / adhesive layer preferably has a glass transition point (Tg) of 50 ° C. or higher. This is because, when a thermoplastic resin having a temperature lower than 50 ° C. is applied, the resin migrates to the base material and then the dye migrates to cause bleeding of the image pattern. The glass transition point is 130 ° C.
When the above thermoplastic resin is applied, the heating medium causes a temperature rise when the image receiving / adhesive layer is thermally transferred to the substrate, and the substrate such as a card may be deformed by heat. Therefore, the glass transition point is 130 ° C.
It is preferable to apply the following thermoplastic resins.

Examples of such a thermoplastic resin include polyester such as linear saturated polyester, vinyl chloride resin such as polyvinyl chloride and vinyl chloride-vinyl acetate copolymer resin, polyacrylic acid, polyacrylic acid-2. -Methoxyethyl, poly (methyl acrylate), poly (acrysan-2-naphthyl), poly (isobornyl acrylate), poly (methacrylomethyl), poly (acrylonitrile), poly (methyl chloroacrylate), poly (methyl methacrylate), poly (ethyl methacrylate), poly (meth) acrylic acid-tert. -Acrylic resins such as butyl, polybutyl isobutyl methacrylate, polyphenyl methacrylate, copolymer resins of methyl methacrylate and alkyl methacrylate (where the alkyl group has 2 to 6 carbon atoms), polystyrene, polydivinylbenzene, polyvinylbenzene Styrene - butadiene copolymer resin, styrene-alkyl methacrylate (carbon number of wherein the alkyl group is 2-6) include vinyl resins such as.

Here, when an image pattern is formed on the surface of the image receiving / adhesive layer by a thermal head via a transfer ribbon, the main component of the image receiving / adhesive layer is made of a thermoplastic resin, and thus the thermal head is left as it is. The image-receiving / adhesive layer is heat-fused to the dye layer of the transfer ribbon by heat, and the image pattern becomes unclear. Therefore, a filler having an anti-blocking property is added to the thermoplastic resin, particularly, an inorganic or organic filler having a heat melting temperature (softening point or decomposition point in the case of an organic filler, melting point in the case of an inorganic filler) 200 ° C. or higher is added. To prevent heat fusion.

Examples of such organic fillers include polytetrafluoroethylene fine particles, starch, silicone resin fine particles, polyacrylonitrile-based fine particles, cured resin fine particles made of benzoguanamine resin and melamine resin. Examples of the inorganic filler include calcium carbonate, talc, kaolin, zinc oxide, titanium oxide, silicon oxide, aluminum hydroxide, magnesium oxide and the like.

The mixing ratio of the thermoplastic resin and the filler is 1 to 20 parts by weight of the filler with respect to 100 parts by weight of the thermoplastic resin.
It may be in the range of 0 parts by weight. Further, the method of applying the image-receiving / adhesive layer is as follows.First, the image-receiving / adhesive layer composition is made into a paint by a suitable solvent, and this paint is applied / dried by means of gravure coating, roll coating, bar coating, etc. Can be formed. The coating amount is set to about 1 to 3 g / m ² .

In the thermal transfer sheet according to claim 7, a primer layer may be provided between the image receiving / adhesive layer and the transparent thin film layer in order to improve the adhesiveness between them. A urethane resin is suitable as such a material, and specifically, a urethane resin including a polyol ion component such as a polyurethane ionomer resin, a polyether polyol, a polyester polyol, and an acrylic polyol, and a prepolymer having an isocyanate group is applied. it can.

Further, in order to prevent discoloration of the dye constituting the image pattern due to light, an ultraviolet absorber having a maximum absorption wavelength of 250 to 400 nm may be added to the image receiving / adhesive layer. Examples of such an ultraviolet absorber include salicylic acid-based ultraviolet absorbers such as phenyl salicylate, p-tert-butylphenyl salicylate, p-octylphenyl salicylate, 2,4-dihydroxybenzophenone, 2-hydroxybenzophenone, and 2-hydroxy. -4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2
Benzophenone-based UV absorbers such as -hydroxy-4-methoxy-5-sulfobenzophenone, 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- (2'-hydroxy-5'-tert-butyl) Phenyl) benzotriazole, 2- (2'-hydroxy-3'-tert-butyl-5'-methylphenyl)
Benzotriazole, 2- (2'-hydroxy-3 ',
5'-ditert-butylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'
-Ditert-amylphenyl) benzotriazole and other benzotriazole-based UV absorbers, 2-ethylhexyl-2-cyano-3,3'-diphenylacrylate, ethyl-2-cyano-3,3-diphenylacrylate and other cyanoacrylates Examples include ultraviolet absorbers.

The mixing ratio of the ultraviolet absorber is 100 parts by weight of the mixture of the thermoplastic resin and the filler.
It may be in the range of 5 to 40 parts by weight.

Further, in the thermal transfer sheet according to claim 6, an information pattern containing an infrared absorbing substance is provided between the peeling layer and the image receiving / adhesive layer, and on the other hand,
In the thermal transfer sheet according to the above, an information pattern containing an infrared absorbing substance is provided in at least a part of the peeling layer and the hologram forming layer, the hologram forming layer and the transparent thin film layer, and between the transparent thin film layer and the image receiving / adhesive layer. The invention according to claims 8 to 10 is characterized in that
The present invention relates to a thermal transfer sheet corresponding to the image display body according to any one of claims 3 to 5, in which the infrared absorbing substance is specified.

That is, the invention according to claims 8 to 10 is based on the thermal transfer sheet according to claim 6 or 7,
In the invention according to, the infrared absorbing material is Fe ²⁺ and / or C
characterized in that it is constituted by a glass-based powder material containing u ^2+, the invention according to claim 9, the infrared-absorbing material contains Fe ²⁺ and / or Cu ²⁺ and five dioxide Phosphorus The present invention according to claim 10 is characterized in that the infrared absorbing substance is tungsten hexachloride and phosphoric acid ester and / or phosphorous acid. And a white reaction product with.

The use of the image display body according to the present invention is arbitrary, and examples include stock certificates, checks, stamps, stamps,
Bills, securities, passbooks, tickets, admission tickets, etc .; cash cards, credit cards, telephone cards, members cards, IC cards, optical cards, etc. ID cards; passports, tickets, etc.

[0054]

According to the image display of the present invention, in addition to the image pattern visually observed by the naked eye and the hologram image, an information pattern containing an infrared absorbing substance and capable of being mechanically read by infrared rays is provided. Because it has
For that reason, it becomes difficult for counterfeiting / alteration, and even if counterfeiting / alteration is performed, authenticity determination by mechanical reading is made in addition to the authenticity determination by the naked eye.
It is possible to discover the fact of alteration more reliably.

On the other hand, according to the image display bodies according to the inventions of claims 3 to 5, the infrared absorbing substance to be applied is white or lightly colored, and the base material of the image display body is made of a white material. By doing so, it is possible to make it difficult to visually inspect the information pattern with the naked eye, so that it is possible to more reliably prevent forgery and alteration.

Further, according to the heat transfer sheet of the invention of claim 6 or 8 to 10, an information pattern containing an infrared absorbing substance is provided between the peeling layer and the image receiving / adhesive layer, while According to the thermal transfer sheet of any one of claims 7 to 10, the infrared absorbing material is present in at least a part of the peeling layer and the hologram forming layer, the hologram forming layer and the transparent thin film layer, and between the transparent thin film layer and the image receiving / adhesive layer. Since the information pattern containing is provided, it is possible to reliably and easily manufacture the image display body according to the first to fifth aspects of the invention.

[0057]

EXAMPLES Examples of the present invention will be described in detail below.

First, a phosphate-based composition having the following composition was melted and crystallized to obtain a phosphate-based white crystalline compound.

(Phosphate composition) P ₂ O ₅ 50.0% by weight CuO 49.5% by weight ZnO 0.5% by weight Incidentally, this compound was subjected to X-ray diffraction using a copper tube. However, diffraction angle (2θ) = 28.14, 30.0
Strong peaks appeared at 7, 30.34 and 44.01, and it was confirmed that they were crystallized.

Next, the phosphate-based white crystals were pulverized into powder, and this was used as an infrared absorbing pigment to prepare an infrared absorbing ink having the following composition.

(Infrared absorbing ink) Pigment (cupric acid phosphate-based white crystalline compound) 30 parts by weight Vinyl chloride-vinyl acetate copolymer resin 10 parts by weight Polyester resin 5 parts by weight Toluene 30 parts by weight Methyl isobutyl ketone 30 parts by weight Parts [Example 1] The thermal transfer sheet according to this example is shown in FIG.
As shown in (A), a base sheet 1 made of a biaxially stretched 25 μm thick polyethylene terephthalate film, a release layer 2 provided on the base sheet 1,
An information pattern (TOP that is provided on the release layer 2 and contains the above-described pigment (cupric acid-containing white crystalline phosphate compound)
Pattern 3 in which the characters are continuously formed) and the image receiving / adhesive layer 4 provided on the entire surface including the information pattern 3 constitute a main part thereof.

Then, this thermal transfer sheet is manufactured through the following steps.

{Production of Thermal Transfer Sheet} (Release Layer Paint) Acrylic Resin 25 parts by weight Toluene 40 parts by weight Methyl ethyl ketone 20 parts by weight Methyl isobutyl ketone 15 parts by weight (Image-receiving / adhesive layer paint) Polyester resin 40 parts by weight Vinyl chloride-vinyl acetate Copolymer resin 5 parts by weight Methyl ethyl ketone 40 parts by weight Toluene 40 parts by weight On the base sheet 1 made of a biaxially stretched polyethylene terephthalate film having a thickness of 25 μm, the release layer coating material is dried at a drying temperature of 110 ° C. using a gravure coater. The release layer 2 was formed by coating with a thickness of 1.5 μm. The information pattern (pattern in which TOP characters are continuously formed) 3 is formed by printing the above infrared absorbing ink on the condition of a film thickness of 1.0 μm by the silk screen printing method, and the gravure is applied from above. Use the coater to receive the above image.
The adhesive layer coating material was applied at a drying temperature of 110 ° C. and a coating thickness of 2.0 μm to form an image receiving / adhesive layer 4, and a thermal transfer sheet as shown in FIG. 1 (A) was manufactured.

{Production of Transfer Ribbon} Dye inks are prepared by dispersing dyes of three colors (yellow, magenta, cyan) in polyvinyl butyral, and each color is applied onto a polyester film having a thickness of 6 μm using a gravure coater. A transfer ribbon having dye layers of three colors was manufactured by coating and drying so as to be alternately arranged.

Then, the thermal transfer sheet and the transfer ribbon thus manufactured are set in the apparatus shown in FIG. 4, and the heating element group of the thermal head is caused to generate heat based on the image data as in the conventional method, and the thermal transfer sheet is heated. A multicolor image pattern 5 made of the above dye is formed on the image-receiving / adhesive layer 4 and the image-receiving / adhesive layer 4 of the thermal transfer sheet is brought into contact with a white card substrate 6 made of polyvinyl chloride. Pressurize and heat the heating medium from the side (heating temperature: 15
At 0 ° C.), the image receiving / adhesive layer 4 is pressure-bonded onto the card base material, and the base sheet 1 is peeled off from the thermal transfer sheet to have an image pattern 5 and an information pattern 3 as shown in FIG. 1B. A card (image display body) was manufactured.

When the card (image display body) thus manufactured is visually inspected with the naked eye, an image pattern 5 consisting of a facial photograph is confirmed as shown in FIG. It was difficult to visually recognize the information pattern 3 of.

On the other hand, 7 for the above card (image display body)
50 nm, 780 nm, 810 nm, 830 nm, 90
When a semiconductor laser beam of 5 nm or the like is irradiated, these laser beams are absorbed by the cupric-containing phosphate-based white crystalline compound in the information pattern 3, so that a mechanical pattern is formed as a black pattern as shown in FIG. 1 (D). It was read.

Example 2 A thermal transfer sheet according to this example has a thickness 25 that is biaxially stretched as shown in FIG.
a base sheet 1 made of a polyethylene terephthalate film of μm, a release layer 2 provided on the base sheet 1, and a hologram forming layer 7 having an uneven pattern 71 provided on the release layer 2 and forming a relief hologram. An information pattern (a pattern in which letters TOP are continuously formed) 3 provided on the hologram forming layer 7 and containing the pigment (cupric acid-containing phosphate white crystal compound) 3 and the uneven surface are provided. A transparent thin film layer 8 made of a material (ZnS) having a refractive index larger than that of the hologram forming layer 7, and an image receiving layer provided on the transparent thin film layer 8.
The main part is constituted by the adhesive layer 4.

The thermal transfer sheet is manufactured through the following steps.

{Production of Thermal Transfer Sheet} (Hologram Forming Layer Paint) Mixture of vinyl chloride-vinyl acetate copolymer resin and urethane resin 35 parts by weight Methyl ethyl ketone 60 parts by weight Toluene 30 parts by weight Biaxially stretched polyethylene terephthalate having a thickness of 25 μm The release layer coating material applied in Example 1 was applied on a base sheet 1 made of a film using a gravure coater at a drying temperature of 110 ° C. and a coating thickness of 1.5 μm to form a release layer 2. The above hologram-forming layer coating material was dried thereon with a gravure coater at a drying temperature of 110 ° C and a coating thickness of 2.0 µm.
After coating and drying with, to form the hologram forming layer 7, the hologram forming layer 7 and the hologram pattern forming surface of the stamper (not shown) are overlapped with each other by a pressing machine, and the temperature is increased to 160 ° C.
Embossing was performed under the heating conditions of No. 1 to form a hologram pattern (concavo-convex pattern 71) on the hologram formation surface.

Next, an information pattern (characters of TOP are continuously formed by printing on the hologram forming layer 7 provided with a hologram pattern by the silk screen printing method using the above infrared absorbing ink under the condition of a film thickness of 1.0 μm. Pattern 3) was formed, and ZnS having a thickness of about 800 angstrom was vacuum-deposited thereon to form the transparent thin film layer 8. Further, the image-receiving / adhesive layer coating material applied in Example 1 was applied on the transparent thin film layer 8 using a gravure coater at a drying temperature of 110 ° C. and a coating thickness of 2.0 μm to form the image-receiving / adhesive layer 4, and FIG. A thermal transfer sheet as shown in (A) was manufactured.

Then, the thermal transfer sheet thus manufactured and the transfer ribbon applied in Example 1 are set in the apparatus shown in FIG. 4, and the heating element group of the thermal head is imaged in the same manner as in Example 1. The multi-color image pattern 5 is formed on the image-receiving / adhesive layer 4 of the thermal transfer sheet by heat generation on the basis of the above, and the image receiving of the thermal transfer sheet is performed on the white type card substrate 6 made of polyvinyl chloride as in the first embodiment. The adhesive layer 4 is brought into contact, and the heating medium is pressed and heated from the thermal transfer sheet side (heating temperature: 150 ° C.) to press-bond the image receiving / adhesive layer 4 onto the card base material 6, and from the thermal transfer sheet to the base sheet. 1 was peeled off to manufacture a card (image display body) having a hollow pattern, an image pattern 5 and an information pattern 3 as shown in FIG.

When the card (image display body) manufactured in this manner was visually observed with the naked eye, an image pattern 5 consisting of a hollow pattern and a facial photograph was confirmed as shown in FIG. It was difficult to visually recognize the information pattern 3 of the same color system.

On the other hand, with respect to the above card (image display body), as in Example 1, 750 nm, 780 nm, 810 nm,
When semiconductor laser light of 830 nm, 905 nm or the like is irradiated, these laser lights are absorbed by the cupric acid-containing phosphate-based white crystalline compound in the information pattern 3, so that FIG.
It was machine-read as a black pattern as shown in FIG.

In this embodiment, the information pattern 3 containing the infrared absorbing substance is formed between the hologram forming layer 7 and the transparent thin film layer 8, but the peeling layer 2 is used.
Card using the thermal transfer sheet having the information pattern 3 formed between it and the hologram forming layer 7, and the thermal transfer sheet having the information pattern 3 formed between the transparent thin film layer 8 and the image receiving / adhesive layer 4. It has been confirmed that even if the display body is manufactured, a card (image display body) that operates in the same manner as in Example 2 described above is obtained.

[0076]

According to the first and second aspects of the present invention, in addition to the image pattern and the hologram image visually observed by the naked eye, an information pattern containing an infrared absorbing substance and capable of being mechanically read by infrared rays is provided. For that reason, it is difficult for counterfeiting / alteration, and even if the counterfeiting / alteration is made, the authenticity determination by mechanical reading is made in addition to the genuineness determination by the naked eye. It has the effect that the fact of alteration can be discovered more reliably.

On the other hand, according to the inventions of claims 3 to 5,
Since the applied infrared absorbing substance exhibits a white color or a light color, it becomes possible to make it difficult to visually observe the information pattern with the naked eye by configuring the base material in the image display body with a white material. It has the effect of more reliably preventing forgery and alteration.

Further, according to the inventions of claims 6 to 10, there is an effect that the image display according to the inventions of claims 1 to 5 can be manufactured reliably and simply.

[Brief description of drawings]

FIG. 1 (A) is a cross-sectional explanatory view of a thermal transfer sheet according to a first embodiment, FIG. 1 (B) is a cross-sectional explanatory view of an image display manufactured using this thermal transfer sheet, and FIG. 1 (C). Shows a front view of the image display body, and FIG. 1D shows a front view of the image display body in which the information pattern is mechanically read.

2 (A) is a cross-sectional explanatory view of a thermal transfer sheet according to Example 2, FIG. 2 (B) is a cross-sectional explanatory view of an image display manufactured using this thermal transfer sheet, FIG. 2 (C). Shows a front view of the image display body, and FIG. 2D shows a front view of the image display body in which the information pattern is mechanically read.

FIG. 3 (A) and FIG. 3 (B) are front views of an image display body according to a conventional example.

FIG. 4 is an explanatory diagram of an apparatus for manufacturing an image display body using a thermal transfer sheet.

5A to 5D are explanatory views showing steps of manufacturing an image display body using a thermal transfer sheet.

[Explanation of symbols]

 1 Base Sheet 2 Release Layer 3 Information Pattern 4 Image Receiving / Adhesive Layer 5 Image Pattern 6 Card Base Material 7 Hologram Forming Layer 8 Transparent Thin Film Layer 71 Concavo-convex Pattern

Claims (10)

[Claims] 1. An image display comprising an image receiving layer having an image pattern formed by sublimation transfer means based on image data on a substrate, wherein the substrate and at least one surface of the image receiving layer contain an infrared absorbing substance. An image display body having a formed information pattern. 2. A hologram forming layer provided with an uneven pattern forming a relief hologram, a transparent thin film layer provided along the uneven surface and having a refractive index higher than that of the hologram forming layer, and adjacent to the transparent thin film layer. And an image receiving layer having an image pattern formed by sublimation transfer means based on image data on a substrate, and the image pattern is recognized together with the hologram image through the hologram forming layer and the transparent thin film layer. In the image display, the hologram forming layer, the transparent thin film layer, the image receiving layer, and an information pattern containing an infrared absorbing substance are formed on at least one surface of the substrate. 3. The infrared absorbing material is Fe ²⁺ and / or C
The image display according to claim 1 or 2, which is made of a glass-based powder material containing u ²⁺ . 4. The infrared absorbing material is Fe ²⁺ and / or C
The image display according to claim 1 or 2, which is composed of a phosphate-based white crystalline powder material containing u ^{2+ and} having phosphorus pentoxide as a main component. 5. The image display according to claim 1, wherein the infrared absorbing substance is composed of a white reaction product of tungsten hexachloride and phosphoric acid ester and / or phosphorous acid. . 6. A thermal transfer sheet used for producing the image display according to claim 1 by a thermal transfer method, comprising a heat resistant base sheet, a release layer provided on the base sheet in a peelable manner, An image pattern is formed on the peeling layer by sublimation transfer means based on image data, and an image receiving / adhesive layer having thermal adhesiveness to the base material of the image display is provided, and the peeling layer and the image receiving layer are provided. A thermal transfer sheet, characterized in that an information pattern containing an infrared absorbing substance is provided between the adhesive layer and the adhesive layer. 7. A thermal transfer sheet used for producing the image display according to claim 2 by a thermal transfer method, wherein a heat resistant base sheet, a release layer provided on the base sheet in a peelable manner, A hologram forming layer provided on the peeling layer and having an uneven pattern, a transparent thin film layer provided along the uneven surface and having a refractive index larger than that of the hologram forming layer, and sublimation based on image data provided on the transparent thin film layer. An image pattern is formed by a transfer means, and an image receiving / adhesive layer having thermal adhesiveness to the base material of the image display is provided, and the peeling layer and the hologram forming layer, the hologram forming layer and the transparent thin film layer, A thermal transfer sheet, characterized in that an information pattern containing an infrared absorbing substance is provided on at least a part of the transparent thin film layer and the image receiving / adhesive layer. 8. The infrared absorbing material is Fe ²⁺ and / or C
The thermal transfer sheet according to claim 6 or 7, which is made of a glass-based powder material containing u ²⁺ . 9. The infrared absorbing material is Fe ²⁺ and / or C
The thermal transfer sheet according to claim 6 or 7, wherein the thermal transfer sheet contains u ²⁺ and is made of a phosphate-based white crystalline powder material containing phosphorus pentoxide as a main component. 10. The infrared absorbing material is composed of a white reaction product of tungsten hexachloride and phosphoric acid ester and / or phosphorous acid.
Alternatively, the thermal transfer sheet according to item 7.