JPH07144484A - Thermal transfer sheet - Google Patents

Abstract

PURPOSE:To provide a thermal transfer sheet applicable to preparing a certificate document capable of preventing forgery, alteration, etc., effectively by enabling truth or falsehood to be judged easily without impairing visibility of a face for information. CONSTITUTION:A structure is arranged so that certificate information such as a face photograph, a sealing part, an ID code, etc., being a part of an image pattern is superimposed on an information part 9 of a monochromatic light regenerative hologram, and the other area is formed of a white light regenerative hologram image 10. A certificate document 12 formed by transferring an image pattern 7 with its thermal transfer sheet 11, through white light is irradiated on a recording part 9 of the monochromatic light regenerative hologram to be reconstructed by monochromatic light, turns only an iridescent color thereby, and is difficult to be confirmed. Its existence can not be easily detected, and besides visual confirmation of certificate information positioned under that can be never influenced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer which comprises an image pattern or a holographic image formed by sublimation transfer means based on image data, and transfers this to a certificate or the like having an information surface requiring security protection. The present invention relates to a sheet, and more particularly to a thermal transfer sheet that does not impair the visibility of the information surface and is easy to determine the authenticity.

[0002]

2. Description of the Related Art As a certificate having this type of security, an image pattern s formed by sublimation transfer means based on image data as shown in FIG. There are known those provided on a base material r made of paper, or those provided with a white light reproduction hologram image t in addition to the image pattern s as shown in FIG. 2B.

A brief description will be given below of a method of manufacturing the latter certificate having the above-mentioned white light reproducing hologram image by a thermal transfer method. First, as shown in FIG. 3 (A), the thermal transfer sheet a used in the production of these certificates 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, and a white light reproduction hologram provided on the release layer c. A hologram forming layer d having a pattern, a transparent thin film layer e provided along the pattern surface and made of a material having a refractive index larger than that of the hologram forming layer, and a sublimation (heat transfer property) provided on the transparent thin film layer e. ) A main part of the image receiving / adhesive layer f is made of a resin material which is dyed with a dye and has thermal adhesiveness to the base material of the certificate.

Then, as shown in FIG. 4, this thermal transfer sheet a is conveyed to a sublimation transfer device j whose main part is composed of a drum h and a thermal head i, and a transfer ribbon k whose colorant 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
An image pattern based on the image data by pressing the thermal head i from the side and appropriately heating the heating element group (not shown) of the thermal head i based on the image data output from an image processing device (not shown). g is formed on the image receiving / adhesive layer f (see FIG. 3B). If the image data has multiple colors, apply transfer ribbons with different color tones.
Similar steps are repeated to form a multicolor image pattern g 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 g is formed is brought into contact with the base material m of the certificate (see FIG. 3C), and the thermal transfer sheet a is heated from the side of the thermal roll. A heating medium n such as a heating plate is pressed and heated to press the image receiving / adhesive layer f onto the base material m, and the heat resistant base sheet b is peeled off from the thermal transfer sheet a to produce a certificate p such as an ID card. (See FIG. 3D).

[0006]

By the way, these certificates can be used for I, such as credit cards and members' cards.
When applied to D cards, the above image patterns and white light reproduction type hologram images in these certificates are patterns that can be visually observed with the naked eye, and therefore face images and hologram patterns are replaced, forgery such as falsification of the described items, etc. There is a problem that it is easily altered and it is difficult to visually confirm the facts of forgery and alteration.

The present invention has been made by paying attention to such a problem, and forgery or alteration that does not impair the visibility of the information surface and can easily make a genuine / counterfeit judgment is performed. An object of the present invention is to provide a thermal transfer sheet applied to the production of certificates that can be effectively prevented.

[0008]

That is, the invention according to claim 1 is a heat-resistant base sheet, a peelable release layer, a hologram forming layer having a light-reproducing hologram, and the hologram forming layer. In a thermal transfer sheet comprising a transparent thin film layer having a larger refractive index, and an image receiving layer having an image pattern transferred and formed by sublimation transfer means and having thermal adhesiveness to the surface of the transferred material, the hologram forming layer is: The hologram of the area corresponding to at least a part of the image pattern is a monochromatic light reproduction type hologram,
The thermal transfer sheet is characterized in that holograms in other areas are white light reproduction type rainbow holograms.

According to a second aspect of the invention, based on the first aspect of the invention, a part of the image pattern corresponding to the area formed by the monochromatic light reproduction hologram is a face photograph, a stamped portion, an ID code, etc. The heat transfer sheet is characterized by the certification information of

According to a third aspect of the present invention, based on the first and second aspects of the present invention, the monochromatic light reproducing hologram is a Fourier transform type or Fresnel type hologram.

[0011]

According to the thermal transfer sheet of the present invention, the information surface of the transferred certificates has a monochromatic light which is difficult to confirm under white light in addition to the image pattern visually observed by the naked eye and the white light reproduction type hologram image. Since the recording portion of the monochromatic light reproducing hologram reproduced by (for example, laser light) is provided, the monochromatic light reproducing hologram cannot be visually detected.
In the case of forgery / alteration, since the authenticity / counterfeit is determined by the above-mentioned monochromatic light reproduction hologram in addition to the authenticity / counterfeit determination by the naked eye, the fact of forgery / alteration can be more surely discovered. Further, since the monochromatic light reproduction hologram is located at a position corresponding to the information surface such as a face photograph, a stamped portion, an ID code, etc., even if this hologram area is irradiated with white light,
It does not impair the visibility of this area simply by showing the iris color.

[0012]

Embodiments of the present invention will be described below in detail with reference to the drawings.

The thermal transfer sheet 11 of the present invention comprises a heat resistant base sheet 1, a peeling layer 2, a hologram forming layer 4, a transparent thin film layer 5 and an image receiving / adhesive layer 6. Examples of the heat-resistant base sheet 1 (hereinafter referred to as the base sheet 1) include, for example, biaxially stretched polyethylene terephthalate film and polyethylene naphthalate film, which have heat resistance such that they are not softened and deformed by heat pressure during transfer.

The release layer 2 formed on the base sheet 1 has an image receiving / adhesive layer 6 on the base material 8 on the surface of the certificate 12.
It is necessary to have a function of a protective film that easily peels from the base sheet 1 when thermally transferring the resin, and that protects the transferred image receiving / adhesive layer 6 and the hologram forming layer 4 from external chemical and mechanical damage. Is. To provide both functions, a mixture of thermoplastic resin and anti-friction agent is applied.

This thermoplastic resin prevents permeation of plasticizers and chemicals and reduces scratches caused by 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 off from the base sheet 1. 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,
Examples thereof include synthetic waxes such as alpha olefin wax and metal salts of higher fatty acids such as zinc stearate.

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

In addition to the above-mentioned components, the peeling layer 2 may contain a peeling improving agent such as a linear saturated polyester resin which improves the cutting property during thermal transfer. However, it is desirable to set the blending 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 2. 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.

The method for applying the release layer 2 is as follows.
The composition constituting the release layer 2 is made into a coating material with an appropriate solvent, and the coating material is applied and dried on the heat resistant base sheet by a coating means such as gravure coating, roll coating coating or bar coating coating. be able to.

Next, the hologram forming layer 4 is formed on the peeling layer 2.
To provide. In this layer, a so-called monochromatic light reproducing hologram embossed area 9 capable of reproducing a hologram image with a laser light having a high coherence or another monochromatic light source, and a white light reproducing type rainbow hologram embossed area are provided on at least one surface portion. 10 and 10. The hologram embossed surface is formed as an interference fringe-shaped uneven embossed pattern obtained by hologram interference light.

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 4. That is, the two-component reactive urethane resin has good embossing moldability, is less likely to cause uneven press, and has good adhesiveness to the transparent thin film layer 5.

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 composed 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. As the above-mentioned isocyanate component, tolylene diisocyanate (TDI),
Xylene diisocyanate (XDI), hexamethylene diisocyanate (HMDI) and the like can be applied.

Further, 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 urethane. You may add up to 30 weight% with respect to resin.

In order to apply such a hologram forming layer, it is possible to form a resin by coating it by a method such as roll coating or blade coating and drying it, and the film thickness is 0.5 to 5 μm. It is set to a degree.

The hologram-forming layer 4 formed in this manner adheres properly to the heat-resistant base sheet coated with the release layer 2 and has excellent moldability by heating and pressing during embossing. Also, the transparent thin film layer 5 does not exhibit adhesiveness to a surface relief type stamper or a hologram stamper whose surface is plated with nickel, gold, chromium or the like.
In addition, it exhibits good adhesiveness, and also has good film cutting property required at the time of transferring the surface of the certificate 12 to the base material 8.

Next, as the material forming the transparent thin film layer 5, a material having a higher refractive index than the hologram forming layer 4 and a high transmittance in the visible light region is used. When the transparent thin film layer 5 having a high refractive index is provided along the hologram forming layer 4, due to the angle dependence of reproduction which is a characteristic of the hologram,
Within the reproducible angle range of the hologram image, the light reflectance of the transparent thin film layer 5 becomes maximum and functions as a "reflection hologram", while outside the reproducible angle range of the hologram image, it functions as a simple transparent body. This is because it becomes possible to see through the image pattern on the body side. As a material for forming such a transparent thin film layer 4,
Examples of the inorganic materials shown in Table 1 include zinc sulfide, titanium oxide, and silicon oxide.

[0027]

[Table 1]

As a method for forming the transparent thin film layer 5, a film forming means such as a vacuum vapor deposition method, a sputtering method or an ion plating method can be applied.
A range of 00 angstroms to 10000 angstroms is suitable. Next, the image receiving / adhesive layer 6 provided on the transparent thin film layer 5 is formed of a thermoplastic resin having an image pattern formed by sublimation transfer means and having thermal adhesiveness to the base material 8 of the certificates 12. The heat transfer is performed on the base material 8 to form a part or the whole surface of the certificate 12.

The image pattern 7 referred to here is security data as a certificate, that is, a face photograph, a stamped portion,
This refers to unique information such as an ID code, and the formation of this information surface is performed according to the position of the Fourier transform type or Fresnel type monochromatic light reproducing hologram in the hologram pattern.

When the thermal melting temperature of the thermoplastic resin is low, part of the image-receiving / adhesive layer 6 is transferred to the transfer ribbon side when the image pattern is formed using a transfer ribbon whose colorant is a sublimable dye (heat There is a risk of 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 6,
In the thermal transfer process of the image receiving / adhesive layer 6 to the transfer target, the temperature setting of the heating medium such as a heat roll or a heating plate must be increased, and the image pattern composed of the sublimable dye is deteriorated (fading).
There is a problem that the base material 8 is damaged by heat. It is also conceivable to add an additive such as silicon into the image-receiving / adhesive layer 6 in order to lower the adhesiveness of the image-receiving / adhesive layer 6 to the transfer ribbon. Results in a problem that becomes worse.

In order to solve such a problem, it is desirable that the image receiving / adhesive layer 6 is composed of a thermoplastic resin having a glass transition point of 50 ° C. or higher and a filler added to the thermoplastic resin. When a thermoplastic resin of less than 50 ° C is applied,
This is because, after being transferred to the base material on the surface of the certificate 12, this resin causes migration of the dye and bleeding of the image pattern occurs. Further, when a thermoplastic resin having a glass transition point of 110 ° C. or higher is applied, the temperature of the image receiving / adhesive layer 6 is thermally transferred to the base material 8 by the heating medium, which causes a base material for certificates such as cards. 8
May be deformed by heat. Therefore, it is preferable to apply a thermoplastic resin having a glass transition point of 110 ° C. or lower.

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 with a thermal head via a transfer ribbon, the main component of the image receiving / adhesive layer is composed of a thermoplastic resin, and thus the image is received by the heat of the thermal head as it is. -The adhesive layer is heat-fused to the dye layer of the transfer ribbon to make the image pattern 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 as raw materials. 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 parts by weight. In addition, the method of applying the image-receiving / adhesive layer 6 is as follows. First, the image-receiving / adhesive layer composition is made into a paint with an appropriate solvent, and this paint is applied / dried by means of gravure coating, roll coating, bar coating, or the like. Can be formed. The coating amount is set to about 1 to 3 g / m ² .

A primer layer may be provided between the image receiving / adhesive layer 6 and the transparent thin film layer 5 in order to improve the adhesiveness between them. As such a material, a urethane resin composed of 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 can be applied.

Further, in order to prevent discoloration of the dye constituting the image pattern 7 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 6. 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, a certificate 12 on which an image pattern is transferred and formed by the thermal transfer sheet of the present invention.
Are not limited to, for example, 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. Can be mentioned.

According to the thermal transfer sheet of the present invention, in addition to the image pattern visually observable with the naked eye and the white light reproduction type hologram image, monochromatic light reproduced by monochromatic light (for example, laser light) which is difficult to confirm under white light. Since it has a reproduction hologram recording unit, it cannot visually detect monochromatic reproduction holograms, so if a counterfeit or alteration is made, in addition to the naked eye authenticity judgment, the above monochromatic light reproduction hologram can be used for authenticity judgment. , It is possible to more reliably discover the fact of forgery / alteration. In addition, since the monochromatic reproduction hologram is located at a position corresponding to the information surface such as a face photograph, a stamped portion, an ID code, etc., even if white light is radiated to this hologram area, it will only show an iris color, Has the advantage of not impairing the visibility.

Further, specific examples of the thermal transfer sheet of the present invention will be described. Example 1 A 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,
A Fourier transform type or Fresnel type monochromatic light reproducing hologram and a white light reproducing type hologram which are provided on the peeling layer 2 and reproduce an image on a predetermined image plane by injecting monochromatic light from a specific direction at a specific angle. Hologram forming layer 4 having hologram recording portion 3 made of rainbow hologram
A transparent thin film layer 5 provided on the hologram forming layer 4 and made of a material (ZnS) having a refractive index larger than that of the hologram forming layer 3, and an image receiving / adhesive layer 6 provided on the transparent thin film layer 5. Its main part is composed. It should be noted that the hologram forming layer 4 has recorded therein one piece of hologram information composed of the letters "OK" reproduced by irradiating with monochromatic light and image information of a rainbow hologram reproduced by irradiating with white light. There is.

Then, this thermal transfer sheet is manufactured through the following steps. {Manufacture of thermal transfer sheet} (Release layer paint) Acrylic resin 30 parts by weight Toluene 40 parts by weight Methyl ethyl ketone 40 parts by weight Methyl isobutyl ketone 20 parts by weight (Hologram forming layer paint) Mixture of vinyl chloride-vinyl acetate copolymer resin and urethane resin 25 Parts by weight methyl ethyl ketone 70 parts by weight toluene 30 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 biaxially stretched 25 μm thick On the base sheet 1 made of polyethylene terephthalate film, the hologram forming layer coating material was dried at a drying temperature of 110 using a gravure coater.
The release layer 2 was formed by coating at a temperature of ℃ and a coating thickness of 1.5 μm.
The hologram forming layer coating material is applied and dried at a drying temperature of 110 ° C. and a coating thickness of 2.0 μm using a gravure coater to form a hologram forming layer 4, and then a monochromatic light reproduction having the information of “OK” as information. Type hologram, or a hologram forming layer of a nickel stamper (not shown) on which a white light reproduction type hologram having an image composed of a rainbow hologram is formed, and the hologram forming layer 4 is overlapped by a press machine. Embossing was performed under heating conditions to form hologram information on the hologram forming layer 4.

Next, a thickness of about 80 is formed on the hologram layer 3.
ZnS of 0 angstrom was vacuum-deposited to form a transparent thin film layer 5, and the above image-receiving / adhesive layer coating material was dried at a drying temperature of 110 ° C. and a coating thickness of 2.0 using a gravure coater.
Then, the image-receiving / adhesive layer 6 was formed by coating with a thickness of μm to manufacture a thermal transfer sheet as shown in FIG.

The transfer ribbon used for forming an image pattern on the thermal transfer sheet of the present invention will be described. {Manufacture of Transfer Ribbon} Dye ink is prepared by dispersing dyes of three colors (yellow, magenta, cyan) in polyvinyl butyral, and each color is alternately arranged on a 6 μm-thick polyester film using a gravure coater. As described above, it was applied and dried to produce a transfer ribbon having dye layers of three colors.

Then, the thermal transfer sheet and the transfer ribbon thus manufactured are set in the apparatus shown in FIG. 4, and a white reproduction hologram image and a positioning mark (which is a hologram or a diffraction grating provided at the same time when the image is taken). Diffracted light (not shown) is detected by the sensor and positioned, and as in the conventional method, the heating element group of the thermal head is made to generate heat based on the image data to receive and bond the image on the position of the monochromatic light reproduction hologram of the thermal transfer sheet. A multicolor image pattern 7 composed of the above dye was formed on the layer 6 to manufacture a thermal transfer sheet of the present invention as shown in FIG. 1 (B).

Next, the image receiving / adhesive layer 6 of the thermal transfer sheet is brought into contact with the base material 8 which is an example of a certificate made of polyvinyl chloride, and the heating medium is pressed and heated from the thermal transfer sheet side (heating temperature: 150 ° C.). Then, the image receiving / adhesive layer 6 is pressure-bonded onto the base material, and the base sheet 1 is peeled off from the thermal transfer sheet to have an image pattern 7 and hologram information.
Certificates as shown in (C) were manufactured.

According to these certificates, there is an information section 9 consisting of a monochromatic light reproduction type hologram on the image pattern 7 consisting of a face photograph, and this is merely recognized as a pattern exhibiting an iris color, and The visibility of the image pattern 7 composed of a photograph is not impaired. In this embodiment, the information part 9 composed of a monochromatic light reproducing hologram is in the same position as the image pattern 7 composed of a facial photograph, but further, an ID code such as a member name or a member number is used as an information area. It can be formed so as to be located above the information portion of the light reproduction hologram. That is, the information area and the information portion of the monochromatic light reproducing hologram can be arbitrarily provided so as to overlap the monochromatic light reproducing hologram.

A method of verifying the certificates 12 will be further described. When the certificate 12 is set at a predetermined position of the reading device shown in FIG. 1D, visible light of, for example, 670 nm with respect to the information portion of the monochromatic light reproducing hologram is set. When the laser L is irradiated from the direction corresponding to the directionality of the interference fringes, the laser light passes through the lens 100 and the screen 10 made of ground glass is used.
An image is formed on the image No. 1 and hologram information consisting of the letters "OK" is projected. Therefore, by setting the certificates 12 in the reading device and confirming the presence or absence of the hologram information, it is possible to mechanically instantly read whether or not the card is a forged card.

[0047]

According to the thermal transfer sheet of the present invention, the certification information such as a face photograph, a stamped portion, an ID code, etc., which is a part of the image pattern, and the information portion of the monochromatic light reproducing hologram are arranged and arranged so as to overlap each other. Certificates in which the image pattern is transferred and formed on this thermal transfer sheet by forming the other area with a white light reproduction hologram image irradiates the recording portion of the single color light reproduction hologram that is reproduced by monochromatic light with white light. However, it is difficult to confirm that the iris color is just present, and its presence cannot be easily detected, and it does not affect the visual recognition of the proof information located below it. Have.

That is, since the certificates can be authenticated by verifying the recording portion formed of this monochromatic light reproduction type hologram, it is difficult for counterfeiting / alteration, and when forgery / alteration is performed. In addition to authenticity determination with the naked eye, authenticity determination with a monochromatic light reproduction hologram is also possible, which has the effect that the fact of forgery / alteration can be found more reliably.

[Brief description of drawings]

FIG. 1A is a cross-sectional explanatory view of a thermal transfer sheet according to the present invention. (B) is a cross-sectional explanatory view of a base material which is an example of a certificate manufactured using the thermal transfer sheet of the present invention.
(C) is a front view of this base material. (D) is an explanatory view showing a method of irradiating a visible light laser on a recording portion formed of a monochromatic light reproducing hologram provided on the base material and reading the hologram information.

2A and 2B are front views of certificates according to a conventional example.

3A to 3D are explanatory views showing a process of manufacturing a certificate using a thermal transfer sheet.

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

[Explanation of symbols]

 1 Base Sheet 2 Peeling Layer 3 Hologram Recording Section 4 Hologram Forming Layer 5 Transparent Thin Film Layer 6 Image Receiving / Adhesive Layer 7 Image Pattern 8 Base Material 9 Information Recording Section Consisting of Monochromatic Reproduction Hologram 10 Image Consisting of White Light Reproduction Hologram Recording part 11 Thermal transfer sheet 12 Certificates

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoaki Shindo 1-5-1, Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd.

Claims (3)

[Claims] 1. A heat-resistant base sheet, a peeling layer provided so as to be peelable, a hologram forming layer having a light-reproducing hologram, a transparent thin film layer having a refractive index higher than that of the hologram forming layer, and a sublimation transfer means. In a thermal transfer sheet comprising an image receiving layer having thermal adhesiveness to the surface of an object to be transferred and having an image pattern transferred, the hologram forming layer is a hologram of an area corresponding to at least a part of the image pattern. Is a monochromatic light reproduction type hologram, and the holograms in other areas are white light reproduction type rainbow holograms. 2. A part of the image pattern corresponding to an area formed by the monochromatic light reproduction hologram is proof information such as a facial photograph, a stamped part and an ID code. Thermal transfer sheet. 3. The thermal transfer sheet according to claim 1, wherein the monochromatic light reproducing hologram is a Fourier transform hologram or a Fresnel hologram.