JP5067241B2 - Transfer foil and anti-counterfeit medium - Google Patents

Description

  The present invention relates to a transfer foil, and more specifically, a transfer layer excellent in security, capable of transferring a fluorescent layer excellent in heat resistance and light resistance with good transferability, and excellent in scratch resistance and solvent resistance after transfer, and The present invention relates to an anti-counterfeit medium.

  In the present specification, “ratio”, “part”, “%” and the like indicating the composition are based on mass unless otherwise specified, and the “/” mark indicates that they are integrally laminated. “PET” is an abbreviation, synonym, functional expression, common name, or industry term for “polyethylene terephthalate”. “Hologram” includes “hologram and those having a light diffractive function such as a diffraction grating”.

  (Main application) The main application of the anti-counterfeit medium transferred using the transfer foil of the present invention is an ID card such as an employee ID card or membership card to improve the unique design and security of the fluorescent layer. In addition, media for certifying rights and qualifications such as prepaid cards, daily necessities and daily necessities, containers for food and various articles, and housings such as electronic devices and office supplies can be applied. However, it is particularly limited if the fluorescent layer with excellent security can be transferred with good transferability, and after transfer, the fluorescent layer with excellent heat resistance and light resistance in addition to scratch resistance and solvent resistance is also required. Is not to be done.

(Background Art) Conventionally, media for the above-mentioned use, for example, media for certifying a right or qualification for paying a certain amount of money (referred to as prepaid) such as an ID card have increased. Since the medium has a certain economic value and effect, individual information such as the validity period, section, name, and age is falsified, and it is constantly falsified, altered, and illegally used. It has been proposed to improve security. In addition, since brand products and high-end products have economic value, they are constantly counterfeited illegally, and various tampering prevention measures have been proposed to improve security. It is known that forgery is difficult, security is excellent, and a fluorescent layer is transferred to a medium. Although the fluorescent layer is not visible under a normal white light source, it is considered that a fluorescent latent image composed of a fluorescent pigment that generates fluorescence in the visible region under infrared or ultraviolet irradiation is formed on the surface of a card or the like. It is done. However, the above-mentioned fluorescent pigment image can be easily rewritten, and identification cards and cash cards are frequently used, and a lot of frictional force is applied to the surface by a card reader. There is a problem that the layer easily peels off. However, since conventional fluorescent layers use fluorescent dyes or fluorescent brighteners, they have the drawback of lacking heat resistance and light resistance. In addition, as a method for forming a fluorescent layer, various images can be easily formed, and thus a simple thermal transfer method is widely used. The fluorescent latent image can be recorded on a transfer medium such as a card by a thermal head or a heating means such as a laser using a thermal transfer foil containing a fluorescent agent in the thermal transfer layer. On the other hand, in a medium for the above-mentioned use, for example, an ID card, images such as letters, numbers, and facial photographs are formed on the surface of the medium. In recent years, these images are often formed by a transfer method by thermal transfer or sublimation transfer using a so-called melt transfer type or sublimation transfer type ink ribbon. The ID card by the transfer method is easy to form images such as letters and numbers, but the image of the thermal transfer method is inferior in durability and friction resistance, the image of the sublimation transfer method is light resistance, weather resistance, There is a problem that the friction resistance is inferior. As a method for solving the durability, many methods for transferring a protective layer (corresponding to the hard coat layer of the present invention) such as a transparent resin layer and a cured resin layer have been proposed.
Therefore, the foil can be easily transferred to a medium such as a branded product or card (transfer object), and the transferred medium is excellent in security, and the surface of the medium can be protected even after repeated use. In addition to scratch resistance and solvent resistance, a transfer foil having a fluorescent layer having excellent durability such as heat resistance and light resistance is required.

(Prior Art) Conventionally, a card in which a fluorescent dye or a fluorescent brightening agent is formed or transferred is known (for example, see Patent Documents 1 and 2). However, conventional fluorescent dyes or optical brighteners have the drawback of lacking durability such as heat resistance, light resistance and weather resistance.
In addition, the applicant of the present invention provides a release layer or a release layer and a protective layer, a hologram forming layer, a hologram effect layer and an adhesive layer on the base film, and the release layer or release layer. Disclosed is a hologram transfer foil characterized in that a fluorescent pigment printing layer containing a colorless or white fluorescent pigment is provided between a protective layer and a hologram forming layer or between the hologram effect layer and the adhesive layer. (For example, refer to Patent Document 3). However, conventional fluorescent pigments have problems such as lack of durability such as light resistance and weather resistance, and two layers of a hologram effect layer and a fluorescent pigment printing layer, which are complicated and expensive to manufacture. .
Further, as an identification mark that can be formed on various articles by a transfer foil or a label, an identification mark having a fluorescent light emitting layer containing an optically active rare earth complex, the rare earth complex having diastereoselectivity. Has a ligand. Since the fluorescent light-emitting layer containing the optically active rare earth complex emits circularly polarized fluorescence in a specific wavelength region, the authenticity determination may be performed by measuring the difference in the intensity of left and right circularly polarized light or the g value. An identification mark that can be used is known (see, for example, Patent Document 4). However, it is a transfer foil characterized in that a fluorescent light emitting layer (identification mark) containing an optically active rare earth complex and an adhesive layer are laminated in this order on a temporary support film, which is transferred to the surface of a medium. If it is used as the outermost surface and is repeatedly used many times, it has a defect that it lacks scratch resistance and solvent resistance and lacks durability.

Japanese Patent Application Laid-Open No. 3-159796 Japanese Patent Laid-Open No. 3-159795- JP 2006-1212 A JP 2005-111704 A

  Accordingly, the present invention has been made to solve such problems. Its purpose is to easily transfer to a medium such as a branded product or card (transfer object), and the transferred medium has excellent security, and the surface of the medium can be used even after repeated use. And providing a transfer foil having a fluorescent layer with excellent durability such as heat resistance and light resistance in addition to scratch resistance and solvent resistance, and an anti-counterfeit medium.

In order to solve the above problems, a transfer foil according to the invention of claim 1 is a transfer foil comprising a base material and at least a release layer, a fluorescent layer and an adhesive layer on one surface of the base material. The fluorescent layer contains a hard coat ionizing radiation curable resin and a fluorescent light-emitting rare earth complex, and the ionizing radiation curable resin has (1) an isocyanate having three or more isocyanate groups in the molecule, and (2) in the molecule. Urethane (the reaction product of polyfunctional (meth) acrylates having at least one hydroxyl group and at least two (meth) acryloyloxy groups), or (3) polyhydric alcohols having at least two hydroxyl groups in the molecule ( meth) cured material of an ionizing radiation curing resin containing acrylate oligomer, and the absorption wavelength region of the ionizing radiation curable resin the ionizing radiation curable resin A transfer foil, wherein Rukoto such cured by irradiation of the absorption wavelength region different from the wavelength 250nm or less in the ultraviolet region of the rare earth complex.
The medium for preventing forgery according to the present invention as claimed in claim 2, using the transfer foil according to claim 1, in the medium for preventing forgery least the phosphor layer and the adhesive layer to the body to be transferred, characterized by comprising a transfer is there.

According to the first aspect of the present invention, when the fluorescent layer is irradiated with ionizing radiation and reacted (cured), it can be cured with the minimum irradiation dose without being inhibited by the rare earth complex, and the fluorescent layer contains the rare earth complex. The light-emitting fluorescent layer can be transferred with good transferability such as foil sharpness when transferring to a medium such as a card (transfer object). The transferred medium is excellent in security and is used many times. Thus, a transfer foil having a fluorescent layer that protects the surface of the medium and is excellent in durability such as heat resistance and light resistance in addition to scratch resistance and solvent resistance is provided even by repeated use.
According to the present invention of claim 2, it is excellent in security and protects the surface of the medium even after repeated use many times, in addition to scratch resistance, solvent resistance, etc., heat resistance, light resistance, etc. An anti-counterfeit medium having a fluorescent layer with excellent durability is provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a sectional view of a transfer foil showing one embodiment of the present invention.
FIG. 2 shows the anti-counterfeit medium of the present invention transferred using the transfer foil of the present invention.

  (Transfer Foil) As shown in FIG. 1, the transfer foil 10 of the present invention is provided with a base material 11 and at least a release layer 13, a fluorescent layer 15, and an adhesive layer 19 on one surface of the base material 11. Thus, the layer structure of the substrate 11 / the release layer 13 / the fluorescent layer 15 / the adhesive layer 19 is obtained. In addition, the anti-counterfeit medium according to claim 2 transfers at least the fluorescent layer 15 by using the transfer foil 10 of the present invention, thereby transferring foil cracks and the like when transferring to a medium such as a card (transfer object). It becomes a medium having a layer structure of fluorescent layer 15 (hard coat property) / adhesive layer 19 / transfer object, and the fluorescent layer 15 becomes the outermost surface, together with the fluorescent layer, the hard coat effect Is expressed. When the fluorescent latent image is provided on the fluorescent layer, the fluorescent layer 15 may be provided in a pattern, or the in-mold transfer foil 10 having the solid fluorescent layer 15 may be cut into a desired pattern shape. .

By doing in this way, the following effects can be produced.
(1) Although the conventional fluorescent light-emitting agent has large crystal particles and could not be blended into the fluorescent layer 15, it can be easily and uniformly dispersed by using a rare earth complex having a molecular weight of about 1500. (2) By including a fluorescent light-emitting rare earth complex having excellent heat resistance and light resistance in the fluorescent layer 15, the fluorescent light emission has much superior heat resistance and light resistance compared to conventional fluorescent light-emitting agents. Sex is obtained. (3) Further, by making the absorption wavelength region of the fluorescent light-emitting rare earth complex different from the absorption wavelength region of the ionizing radiation curable resin, curing of the ionizing radiation curable resin of the fluorescent layer 15 can be performed with a fluorescent light emitting agent. Can be cured sufficiently. (4) Moreover, since the fluorescent layer 15 is mainly composed of a cured product of an ionizing radiation curable resin, it also has a hard coat property, so that durability such as scratch resistance and solvent resistance is imparted and protected. The effect can also be used. (5) Therefore, a fluorescent layer and a protective layer such as a hard coat layer that protects the fluorescent layer can be incorporated into the fluorescent layer 15 with a fluorescent light-emitting rare earth complex. One fluorescent layer 15 having a coating property can be formed.

  (Substrate) As the substrate 11, various materials can be applied depending on the use as long as the substrate 11 has heat resistance, mechanical strength, mechanical strength to withstand manufacturing, solvent resistance, and the like. For example, polyester resins such as polyethylene terephthalate / polybutylene terephthalate / polyethylene naphthalate, polyamide resins, vinyl resins such as polyvinyl chloride, acrylic resins, imide resins, engineering resins such as polyarylate, polycarbonate, cyclic polyolefin There are cellulosic films such as cellulosic resins and cellophane. The substrate may be a copolymer resin containing these resins as a main component, a mixture (including an alloy), or a laminate composed of a plurality of layers. Usually, polyester films such as polyethylene terephthalate and polyethylene naphthalate are preferably used because of their good heat resistance and mechanical strength, and polyethylene terephthalate is most suitable.

  The substrate 11 may be a stretched film or an unstretched film, but a film stretched in a uniaxial direction or a biaxial direction is preferable for the purpose of improving the strength. The thickness of the base material is usually about 2.5 to 50 μm, preferably 2.5 to 12 μm, and most preferably 4 to 6 μm. Prior to coating, the substrate 11 is applied to the coated surface by corona discharge treatment, plasma treatment, ozone treatment, flame treatment, primer (also called anchor coat, adhesion promoter, or easy adhesive) coating treatment, pre-heat treatment, dust removal. Easy adhesion treatment such as treatment, vapor deposition treatment, and alkali treatment may be performed. Moreover, you may add additives, such as a filler, a plasticizer, a coloring agent, and an antistatic agent, as needed.

  (Release layer, release layer) In order to improve the releasability during transfer, a release layer 13 is provided, and if necessary, a release layer may be provided, and both the release layer 13 and the release layer are provided. The transferability can be further improved.

  (Release layer) The release layer 13 is usually a release resin, a resin containing a release agent, a curable resin that is cross-linked by ionizing radiation, but is not particularly limited, but is preferably a melamine resin. It is. By combining with fluorescence 15 to be described later, the releasability from the release layer 13 is stabilized, and the transferability during transfer can be improved.

  The release layer 13 is formed by dispersing or dissolving the resin in a solvent, applying and drying the resin by a known coating method such as roll coating or gravure coating, and baking at a temperature of about 150 ° C to 200 ° C. The thickness of the release layer 13 is usually about 0.01 μm to 5.0 μm, preferably about 0.5 μm to 3.0 μm.

  (Peeling layer) The peeling layer provided as necessary includes acrylic resins, vinyl resins, polyester resins, and fiber resins with release resins such as fluorine resins, silicones, and various waxes added or copolymerized. Wax, melamine-based resin, etc., and when both the release layer 13 and the release layer are provided, they may be used in appropriate combination. In this case, the release layer has a function as a protective layer after transfer. Have.

  (Fluorescent layer) The fluorescent layer 15 is mainly composed of a fluorescent light-emitting rare earth complex and an ionizing radiation curable resin, and preferably contains microsilica or polyethylene wax as a filler. The fluorescent layer 15 contains an ionizing radiation curable resin and a filler, so that the outermost surface is formed after transfer, and exhibits higher durability such as scratch resistance (also called scratch resistance), abrasion resistance and solvent resistance. To do. More preferably, the adhesive layer 19 contains microsilica as a filler, and the filler is mixed into all the layers to be transferred, so that the foil sharpness at the time of transfer to a medium such as a card (transfer object 101) is improved. Can be transferred.

  The ionizing radiation curable resin is preferably (1) an isocyanate having three or more isocyanate groups in the molecule, and (2) at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule. Preferably using an ionizing radiation curable resin containing a polyfunctional (meth) acrylate having, or (3) a urethane (meth) acrylate oligomer which is a reaction product of a polyhydric alcohol having at least two hydroxyl groups in the molecule. May contain polyethylene wax, applied, dried, and cured with ionizing radiation to form an ionizing radiation curable resin.

  The ionizing radiation curable resin containing the urethane (meth) acrylate oligomer (referred to herein as the ionizing radiation curable resin composition M) is a cured ionizing radiation curable resin containing the urethane (meth) acrylate oligomer. Products, specifically, a photocurable resin disclosed in JP-A-2001-329031, MHX405 varnish (trade name of ionizing radiation curable resin, manufactured by The Inktec Co., Ltd.), Iupimer UV V3031 ( An example is an ionizing radiation curable resin trade name manufactured by Mitsubishi Chemical Corporation.

  Examples of the (polyethylene wax) filler include micro silica and polyethylene wax. Examples of the polyethylene wax include polyethylene resin particles and beads, and spherical beads are preferable. However, when polyethylene wax is added, the foil breakage is reduced, so the amount added is about 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, with respect to 100 parts by weight of ionizing radiation curable resin. And After the transfer, the fluorescent layer 15 becomes the outermost layer, and the contained polyethylene wax protects the medium from mechanical friction and abrasion, and also protects unique information such as an image to be described later.

  (1) By including polyethylene wax, the hard coat layer 14 becomes the outermost surface layer after transfer, but it can be used in extremely harsh environments, used for a long period of time, and / or repeatedly used many times. It protects the image provided on the transfer material from solvent, mechanical friction, and abrasion, and is resistant to scratches and has excellent durability. (2) Since the fluorescent layer 15 is in contact with the release layer 13 using the melamine-based resin, the fluorescent layer 15 peels between the fluorescent layer 15 and the release layer 13 and has stable release properties. Generation of burrs and the like can be extremely reduced. (3) Since the fluorescent layer 15 contains microsilica or polyethylene wax as a filler, and the adhesive layer 19 contains microsilica as a filler, the filler is mixed into all layers to be transferred. The foil sharpness at the time of transfer to a medium (the transfer target 101) such as the above can be improved, and the transferability can be improved together with the stable releasability of (2).

(Rare earth complex) A fluorescent light-emitting rare earth complex is an optically active rare earth complex that emits fluorescence, which means a rare earth complex having an optically active site, in which a ligand having an optically active site is coordinated. Or, one of the two stereoisomers (Δ-form, Λ-form) existing in the absolute configuration around the rare earth metal atom of the tetragonal prismatic coordination structure of the rare earth complex is excessively contained. The rare earth complex in the state of being. The rare earth complex having such a structure has excellent emission characteristics and a sharp emission spectrum with a narrow half-value width. In particular, rare earth complexes in which the rare earth ion Ln ³⁺ is any one of Eu ³⁺ , Tb ³⁺ , Yb ³⁺ , Nd ³⁺ , Er ³⁺ , Sm ³⁺ , Dy ³⁺ , and Ce ³⁺ are weakly excited. It is a strong light-emitting rare earth complex that emits strong light even with light, and is preferably used. For example, there are general formula (1), general formula (2), general formula (3), and general formula (4). The rare earth complex preferably contains a <—C _n F _{2n + 1} (n is an integer of 1 to 22)> group from the viewpoint of heat resistance and stability. Specific examples include Lumisys (registered trademark, total distributor: Central Techno Co., Ltd., manufacturer: Nissei Chemical Industry Co., Ltd.) R-600, G-900, YB-1200, and the like. Details are described in WO2005 / 044770, JP2006-249075A, and JP2005-97240A.

（式中、Ｄは重水素原子、ハロゲン原子又は水素原子を含まないＣ１〜Ｃ２２の脂肪族基を示す）

(Wherein D represents a C1-C22 aliphatic group containing no deuterium atom, halogen atom or hydrogen atom)

(Wherein X represents C—R or N, and R represents a hydrogen atom or a substituent)

  (Formation of fluorescent layer) The fluorescent layer 15 is formed by the ionizing radiation curable resin, fluorescent light-emitting rare earth complex, silicone, microsilica or polyethylene wax, photopolymerization initiator, plasticizer, stabilizer as necessary. Then, a surfactant or the like is added, dispersed or dissolved in a solvent, applied by a known coating method such as roll coating, gravure coating, comma coating or die coating, dried, and reacted (cured) with ionizing radiation. .

  By using a rare earth complex having a high luminous efficiency, the proportion of the fluorescent light emitting rare earth complex contained in the ionizing radiation curable resin that is the binder resin is about 0.01 to 10%, preferably 0.1. ~ 5%. If it is less than this range, the intensity of the fluorescence emission is small, and if it exceeds this range, the intensity of the fluorescence emission is too high, resulting in a high cost.

  (Wavelength region) Further, as the ionizing radiation curable resin which is a binder resin, among the resin systems, there is no absorption or small absorption in the absorption wavelength region of the fluorescent luminescent rare earth complex and the fluorescent emission wavelength region. Is preferred. When absorption occurs in the absorption wavelength region of the fluorescent light-emitting rare earth complex, when the ionizing radiation curable resin is irradiated with ionizing radiation and reacted (cured) to form the fluorescent layer 15, the rare earth complex is ionizing radiation 1. Part of the water is absorbed, resulting in poor reaction (curing) and insufficient durability, or a large amount of irradiation is required, resulting in high cost. In this respect, an ionizing radiation curable resin system containing the urethane (meth) acrylate oligomer is preferable, and the resin system can be cured by irradiation in an ultraviolet region having a wavelength of 250 nm or less. In addition, when there is absorption in the fluorescence emission wavelength region of the fluorescent light-emitting rare earth complex, ionizing radiation is emitted when, for example, ultraviolet rays are irradiated to fluoresce the medium on which the fluorescent layer 15 / adhesive layer 19 is transferred. The cured resin absorbs part of the ultraviolet rays, resulting in poor light emission and insufficient luminance of the fluorescent latent image, or requiring a large amount of irradiation, resulting in an increase in size and cost due to the high output of the fluorescent light emitting device. It ends up. The absorption wavelength region of the ionizing radiation curable resin before curing and the ionizing radiation curable resin after curing are the same.

  (Thickness of the fluorescent layer) The thickness of the fluorescent layer 15 is usually about 1 to 5 μm. However, in the present invention, it is used in an extremely severe environment, has no expiration date, and / or is used for a long time. The fluorescent layer 15 has a thickness of 5 μm or more, preferably 10 μm or more in order to protect the image from solvents and mechanical friction and wear, especially scratching, and to give durability not easily damaged even after repeated use. More preferably, it is 15 μm or more. Although the upper limit is not particularly limited, it is about 25 μm or less from the viewpoint of price and foil breakability. The thickness of the fluorescent layer 15 is 5 μm or more, preferably 10 μm or more, more preferably 15 μm or more, so that the durability is enhanced, and the use in extremely harsh environments, no expiration date, or long-term use And / or a transfer foil capable of protecting an image from a chemical mechanical external force even after repeated use.

  If the total thickness of the fluorescent layer 15 / adhesive layer 19 that is a layer to be transferred is thick, burrs are generated, and the transferability such as a drop in the foil and a decrease in the transfer speed is remarkably reduced. If it contains, since it can improve peelability and foil cutting property, it can be transferred easily.

  (Adhesive layer) As the adhesive layer 19, a heat-sensitive adhesive that melts or softens when heated and exhibits an adhesive effect can be applied. Specifically, a vinyl chloride resin, a vinyl acetate resin, or vinyl chloride. Examples thereof include vinyl acetate copolymer resins, acrylic resins, and polyester resins. The adhesive layer 19 preferably contains a filler such as microsilica in terms of the ability to break the foil. Further, the resin of the adhesive layer 19 is preferably one having a melting point of 60 to 95 ° C. which melts and adheres at a low temperature of about 95 ° C. and solidifies and adheres at about 60 ° C. When the melting point is less than the above range, the adhesiveness to the transfer medium is insufficient, and the temperature at which the formed image is used is limited. On the other hand, when the melting point exceeds the above range, the transferability becomes insufficient by heating with a thermal head, the foil breakability of the hard coat layer is lowered, and burrs are easily generated.

  The preferred adhesive layer 19 contains a heat-adhesive polyester resin and microsilica, and the ratio of the heat-adhesive polyester resin and the microsilica is based on a mass-based polyester resin: microsilica = 90 to 94: 6-10. If the content of the microsilica is less than the above range, the foil sharpness is poor, and if it exceeds the above range, the transparency is lowered and the image becomes difficult to see.

  The material resin is dissolved or dispersed in a solvent, an additive such as a pigment is added as appropriate, and the layer is applied and dried by a known method such as roll coating, gravure coating, or comma coating, and a layer having a thickness of 1 to 30 μm Get.

  (Transfer) Using the transfer foil 10 of the present invention thus obtained, at least the fluorescent layer 15 / adhesive layer 19 is transferred to the transfer target. In addition, although it peels between the mold release layer 13 and the fluorescent layer 15 at the time of transcription | transfer, a part of mold release layer 13 may transfer to the fluorescent layer 15 slightly, but it is in the scope of the present invention. The transfer may be a transfer method to a transfer target, and may be a known transfer method, for example, hot stamping by hot stamping (foil stamping), whole surface or stripe transfer by a thermal roll, thermal printer using a thermal head (thermal printing head). A known method such as a thermal transfer printer can be applied. Any shape such as a spot shape, letters, numbers, and illustrations may be transferred. A thermal printer capable of continuously operating variable information such as a face photograph having a different arbitrary shape or printing on demand is preferable. In this way, the foil can be easily transferred to a medium such as a card (transfer object) with ease.

  (Transfer to be transferred) The transfer target 101 is not particularly limited. For example, natural fiber paper, coated paper, tracing paper, plastic film that is not deformed by heat during transfer, glass, metal, ceramics, wood, cloth or Any medium such as a dye-accepting medium may be used, and it may be appropriately selected depending on the application. Further, at least a part of the medium of the transfer target 101 may be subjected to image, coloring, printing, or other decoration.

  (Durability) By using the transfer foil 10 of the present invention, the outermost surface of the transfer object is composed of the fluorescent layer 15 and is excellent in durability such as scratch resistance and solvent resistance without providing a separate protective layer. . The pencil hardness test of the fluorescent layer 15 that is the outermost surface is measured according to JIS-K5400, and a hardness of H or higher is preferable. Further, the scratch strength of the fluorescent layer 15 is 150 g or more, preferably 200 g or more, from the viewpoint of sufficient friction resistance on the surface. The scratch strength was measured using a wear resistance tester (HEIDON-18) on a sample conditioned at 23 ° C. and 55% RH for 24 hours, with a 0.8 mmφ sapphire needle at a right angle. As a result, the load applied to the sapphire needle was gradually increased from 0 g to 200 g, and the load when the surface began to be scratched was measured while sliding and moving the sample surface at 60 cm / min. The larger the load, the better. Protects the surface of the medium even after repeated use and protects it from mechanical and chemical damage over a long period of time, so there is no gas station card or construction site card used in extremely harsh environments and no expiration date It can also be suitably used for long-term entrance / exit cards, point cards, and entrance / exit cards that repeatedly enter and exit a number of security-controlled rooms such as financial institutions.

  The fluorescent layer 15 emits light by a fluorescent light-emitting rare earth complex, and is excellent in durability such as heat resistance and light resistance. The fluorescent layer 15 is not observable with normal visible light, and preferably emits visible light when irradiated with light of a specific wavelength. The light source preferably has a wavelength in the ultraviolet region, and an ultraviolet LED, black light, xenon lamp, short wavelength semiconductor. A laser etc. can be illustrated.

  When the fluorescent latent image is transferred to the transfer target using the transfer foil 10 of the entire surface of the fluorescent layer 15, hot stamping (foil stamping) by thermal stamping, entire surface or stripe transfer by a thermal roll, thermal head ( A mold corresponding to a known method such as a thermal printer (also referred to as a thermal transfer printer) using a thermal printing head) or data output in an arbitrary shape may be sent to the thermal head for transfer. Spot shapes such as circles and stars, letters, numbers, illustrations, etc. are formed according to the mold and data. Of course, it may be transferred in a solid form.

  Further, the present invention can be applied to a plurality of colors, a full color, and the like by using a plurality of fluorescent layers using a fluorescent luminescent rare earth complex that emits RGB light. For example, as a hard coat layer / R light emitting fluorescent layer / G light emitting fluorescent layer / B light emitting fluorescent layer, offset printing or gravure printing can be used to produce a color tone. If a photo of the owner's face is formed on the fluorescent layer 15 as a latent image, it cannot be seen by a person who impersonates maliciously, can be visualized at the time of use and compared with the person, and immediately differs from the owner. Can be found. For example, if the owner name is provided for both the latent image and the visible image associated with the owner, the forged medium can only forge the visible image, and the invisible latent image can be created. Since it does not emit light even when it is irradiated with ultraviolet rays, it can be immediately detected that it is counterfeit without being visualized, and security can be improved.

The heat resistance of the fluorescent light-emitting rare earth complex used for the fluorescent layer 15 was resistant to about 250 ° C., and even when the fluorescent layer 15 was left in a 200 ° C. environment for 1 hour, there was no significant change in emission luminance.
In addition, the weather resistance test measured according to JIS-B-7753 (Sunshine carbon arc lamp type light resistance and weather resistance tester) compares the color change of the printed matter after irradiation for 500 hours with that before irradiation. Although it evaluated visually, there is no remarkable change after 500 hours, and it is excellent also in light resistance. As described above, a fluorescent layer having excellent durability such as heat resistance, light resistance, and weather resistance can be obtained by the fluorescent light-emitting rare earth complex.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, it is not limited to this. In addition, except a solvent, each composition of each layer is a mass part of solid content conversion.

Example 1 Using a PET film having a thickness of 25 μm as the base material 11, a TCM01 medium (manufactured by Dainippon Ink Co., Ltd., melamine resin product name) coating liquid is applied to one surface of the base material 11 by a gravure coating method. After being dried, it was applied to a thickness of 2 μm, dried, and baked at 180 ° C. for 20 seconds to form a release layer 13.
The release layer 13 is coated with the following phosphor layer composition with a gravure reverse coater so that the coating thickness after drying is 6 μm, dried at 100 ° C., and then irradiated with ultraviolet light using a high-pressure mercury lamp. And cured to form the fluorescent layer 15.
First, “ionizing radiation curable resin composition M” was produced by the following procedure. A reactor equipped with a stirrer, reflux condenser, dropping funnel and thermometer was charged with 206.1 g of ethyl acetate and 133.5 g of isophorone diisocyanate trimer (HULS product, VESTANAT T1890, melting point 110 ° C.), 80 The solution was heated to 0 ° C. and dissolved. After air was blown into the solution, 0.38 g of hydroquinone monomethyl ether, 249.3 g of pentaerythritol triacrylate (product of Osaka Organic Chemical Industry Co., Ltd., Viscoat 300) and 0.38 g of dibutyltin dilaurate were charged. After reacting at 80 ° C. for 5 hours, 688.9 g of ethyl acetate was added and cooled. A phosphor layer composition is prepared by blending the “ionizing radiation curable resin composition M”, a film-forming resin (acrylic oligomer), a rare earth complex, polyethylene wax, a photopolymerization initiator, and a solvent in the following composition. did.
・ <Fluorescent layer composition>
“Ionizing radiation curable resin composition M” 25 parts by mass Methacrylate oligomer (product name: Nikko Synthetic Chemical Co., Ltd., trade name: Murasaki 6630B) 5 parts by mass Lumisis R-600 (manufactured by Central Techno Co., Ltd., product name of red-emitting rare earth complex)
0.3 parts by mass Polyethylene wax (average particle size 5 μm) 0.6 parts by mass Photopolymerization initiator (Ciba, trade name Irgacure 907) 0.9 parts by mass Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts by mass Next, the surface of the fluorescent layer 15 was coated and dried to a thickness of 0.5 μm by gravure coating using a primer layer composition working solution having the following composition, and then dried at 45 ° C. at 24 ° C. Time aging formed a primer layer.
・ <Primer layer composition working solution>
Polyester resin 10 parts Vinyl chloride-vinyl acetate copolymer 10 parts Toluene 40 parts Methyl ethyl ketone 40 parts Next, the following adhesive layer composition is dried on the primer surface with a gravure coater so that the coating amount becomes 1 μm. Application and drying were performed at 100 ° C. to form an adhesive layer 19.
・ <Adhesive layer composition>
Polyester resin SP170 (manufactured by Nippon Synthetic Chemical Co., Ltd., trade name) 20 parts by mass Microsilica (average particle size 0.5 μm) 1.5 parts by mass Solvent (MEK: toluene = 1: 1) 78.5 parts by mass As described above Thus, the transfer foil 10 of Example 1 having a layer structure of the base material 11 / the release layer 13 / the fluorescent layer 15 / the primer layer / the adhesive layer 19 was obtained.

(Example 2) As the fluorescent layer 15, a transfer foil 10 of Example 2 was obtained in the same manner as in Example 1 except that the following fluorescent layer composition was used.
・ <Fluorescent layer composition>
Iupimer UV / V3031 (Mitsubishi Chemical Co., Ltd., UV curable resin product name) 25 parts by mass Methacrylate oligomer (Nippon Gosei Kagaku Co., Ltd., product name: Muriko 6630B) 5 parts by mass Lumisys G-900 (Central Techno Co., Ltd., green light emission) Rare earth complex trade name)
0.3 part by weight Microsilica 1 part by weight Photopolymerization initiator (Ciba, trade name Irgacure 907) 0.9 part by weight Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts by weight

(Example 3) Instead of the fluorescent layer 15, the following hard coat layer composition, red light emitting fluorescent layer composition, green light emitting fluorescent layer composition, and blue light emitting fluorescent layer composition were used. .
First, using a transparent hard coat layer composition, the coating thickness after drying was 6 μm with a gravure reverse coater and dried at 100 ° C. to form a hard coat layer.
Use a gravure printing method to print a photo of the face using a red luminescent phosphor layer composition, a green luminescent phosphor layer composition, or a blue luminescent phosphor layer composition, and then use a high pressure mercury lamp. The phosphor layer 15 was formed by irradiating with ultraviolet rays and curing. Otherwise in the same manner as in Example 1, the transfer foil 10 of Example 3 was obtained.
・ <Hard coat layer composition>
MHX405 varnish (trade name of ionizing radiation curable resin, manufactured by The Inktec Co., Ltd.)
25 parts by mass Methacrylate oligomer (manufactured by Nippon Synthetic Chemical Co., Ltd., trade name: Purple light 6630B) 5 parts by mass Polyethylene wax (average particle size: 5 μm) 0.6 parts by mass Photopolymerization initiator (product name: Irgacure 907, manufactured by Ciba) 0. 9 parts by mass Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts by mass <Red fluorescent layer composition>
“Ionizing radiation curable resin composition M” 25 parts by mass Methacrylate oligomer (product name: Nikko Synthetic Chemical Co., Ltd., trade name: Murasaki 6630B) 5 parts by mass Lumisis R-600 (manufactured by Central Techno Co., Ltd., product name of red-emitting rare earth complex)
0.3 parts by mass Polyethylene wax (average particle size 5 μm) 0.6 parts by mass Photopolymerization initiator (Ciba, trade name Irgacure 907) 0.9 parts by mass Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts by mass <Green phosphorescent layer composition>
MHX405 varnish (trade name of ionizing radiation curable resin, manufactured by The Inktec Co., Ltd.)
25 parts by mass Methacrylate oligomer (manufactured by Nippon Synthetic Chemical Co., Ltd., trade name: Purple light 6630B) 5 parts by mass Lumisys G-900 (manufactured by Central Techno Co., Ltd., trade name of green-emitting rare earth complex)
0.3 parts by mass Polyethylene wax (average particle size 5 μm) 0.6 parts by mass Photopolymerization initiator (Ciba, trade name Irgacure 907) 0.9 parts by mass Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts by mass <Blue light emitting phosphor layer composition>
MHX405 varnish (trade name of ionizing radiation curable resin, manufactured by The Inktec Co., Ltd.)
25 parts by mass methacrylate oligomer (manufactured by Nippon Synthetic Chemical Co., Ltd., trade name: purple light 6630B) 5 parts by mass Lumisis YB-1200 (manufactured by Central Techno Co., Ltd., trade name of blue-emitting rare earth complex)
0.3 parts by mass Polyethylene wax (average particle size 5 μm) 0.6 parts by mass Photopolymerization initiator (Ciba, trade name Irgacure 907) 0.9 parts by mass Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts by weight

Comparative Example 1 A transfer foil of Comparative Example 1 was obtained in the same manner as in Example 1 except that the following composition was used as the fluorescent layer composition of the fluorescent layer 15.
・ <Fluorescent layer composition>
MHX405 varnish (trade name of ionizing radiation curable resin, manufactured by The Inktec Co., Ltd.)
25 parts by weight Methacrylate oligomer (manufactured by Nippon Synthetic Chemical Co., Ltd., trade name Purple Light 6630B) 5 parts by weight Optical brightener 0.3 part by weight Polyethylene wax (average particle size 5 μm) 0.6 part by weight Photopolymerization initiator (Ciba) Manufactured, trade name Irgacure 907) 0.9 parts by mass Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts by mass

(Evaluation test) Evaluation was carried out by transferring to a transfer material and evaluating the transferability, surface hardness after transfer, scratch property, and light resistance of the printed image.
First, a credit card specification card made of polyvinyl chloride is used as the transfer target 101, and a sublimation thermal transfer sheet (Dai Nippon Printing Co., Ltd., yellow, magenta, cyan) is applied to the surface of the transfer target 101. Using a color standard ribbon), a face photograph and name as unique information were printed with a 600 dpi thermal transfer printer to form an image.
With the FARGO card printer HDP820, the adhesive layer 19 surface of the transfer foil 10 of the example and the comparative example is overlapped on the image surface, the entire surface is thermally transferred, the base material is peeled off and gradually removed, and the anti-counterfeit medium 100 did.

(Evaluation results) In Examples 1 to 3 and Comparative Example 1, the releasability at the time of transfer was good, the foil breakage was good, and transfer was normally performed.
Moreover, when the pencil hardness test of the anti-counterfeit medium 100 surface of Examples 1 to 3 and Comparative Example 1 was measured according to JIS-K-5400, it had a hardness of 2H or more. The scratch strength of the surface of No. 3 was 200 g or more of sapphire and had sufficient durability. This indicates that even when a fluorescent light-emitting rare earth complex was included in the fluorescent layer, the absorption of the fluorescent light-emitting agent did not hinder the curing of the ionizing radiation-curable resin, and was sufficiently cured.

In addition, the light resistance is measured in accordance with JIS-B-7773 (Sunshine carbon arc lamp type light resistance and weather resistance tester) using the anti-counterfeit medium 100, and the color of the image after irradiation for 500 hours. The change was evaluated by visual comparison with that before irradiation. Even in the anti-counterfeit medium 100 using any of the transfer foils 10 of Examples 1 to 3, there was no significant change and good light resistance. This is the light resistance obtained by limiting the material of the fluorescent luminescent agent to be included in the fluorescent layer to the rare earth complex, and the design and security could be improved. Furthermore, when the fluorescent layer was irradiated with ultraviolet rays with a black light having a wavelength of 365 nm, fluorescence was emitted.
However, in the anti-counterfeit medium 100 using Comparative Example 1, the fading was remarkably poor.

It is sectional drawing of the transfer foil which shows one Example of this invention. It is the forgery prevention medium of this invention transcribe | transferred using the transfer foil of this invention.

Explanation of symbols

10: Transfer foil 11: Base material 13: Release layer 15: Fluorescent layer 19: Adhesive layer 100: Anti-counterfeit medium 101: Transfer object

Claims (2)

In a transfer foil comprising a substrate and at least a release layer, a fluorescent layer and an adhesive layer on one surface of the substrate,
The fluorescent layer includes a hard coat ionizing radiation curable resin and a fluorescent light-emitting rare earth complex,
The ionizing radiation curable resin (1) is an isocyanate having three or more isocyanate groups in the molecule, (2) a polyfunctional (meth) having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule. Acrylates, or (3) a cured product of an ionizing radiation curable resin containing a urethane (meth) acrylate oligomer which is a reaction product of a polyhydric alcohol having at least two hydroxyl groups in the molecule,
And, transfer foil, wherein Rukoto such cured by irradiation of the absorption wavelength region different from the wavelength 250nm or less in the ultraviolet region of the ionizing radiation curable resin absorption wavelength region of the ionizing radiation-curable resin wherein the rare earth complex . Using a transfer foil according to claim 1, the medium for preventing forgery least the phosphor layer and the adhesive layer to the body to be transferred, characterized by comprising a transfer.

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