JP2013101235A - Image display body and method of manufacturing image display body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a higher quality image display body requiring high security, improved in visibility, having prevention performance against forgery, falsification or alteration, and making it easy to find a suspicious fraudulent article through observation even when an illegal act is committed.SOLUTION: An image display body obtained by thermally transferring hologram transfer foils as a plurality of image cells to a base material to be transferred, comprises: at least the base material; and a peeling layer, an image receiving layer, an adhesion layer, a transparent reflection layer, and a hologram layer laminated on one surface of the base material. The hologram layer has two or more kinds of different relief structure formation portions. A content ρ of inorganic fine particles included in the adhesion layer is larger than 0.02 and smaller than 1.0, and permeability η of the adhesion layer is smaller than a value obtained by adding 0.15 to 1.8 times of a turbidity ε of the adhesion layer.

Description

  The present invention relates to an image display body that prints, prints, and draws a face image and a fingerprint that are important for individual identification on a booklet such as a passport or a visa, or a personal authentication medium such as a card. In particular, the examiner who makes personal identification information such as the face of the right owner easy to form personal identification information by combining the structure with relief structure and on-demand printing technology The present invention relates to a technology that makes it easy to identify and makes forgery and alteration difficult, or makes it easier for an examiner to detect.

  Many personal authentication media such as passports and ID (identification) cards use facial images to enable visual personal authentication. For example, in a passport, conventionally, photographic paper on which a face image is printed is pasted on a booklet. However, the passport to which the photographic paper is pasted has been falsified by replacing the photographic print.

  For these reasons, in recent years, face image information has been digitized and reproduced on a booklet. As this image reproduction method, sublimation (heat transferable) dyes, thermal transfer recording methods using transfer ribbons using resin-type melting type or wax-melting type in which pigments are dispersed, or electrophotography are being studied. ,It is used.

  In addition to the above method, the image reproduction method to the passport includes a recording method using an inkjet printer (Patent Document 1), a laser printing recording method using a carbon dioxide laser or a YAG laser and a thermal color former (Patent Document 2), and further There is a laser engraving print recording method (Patent Document 3) in which carbon (C) existing in a base material is used for printing and recording in the depth direction of the base material.

  Further, as an image display body containing this kind of personal recognition data, an image pattern formed based on the image data is provided on a card substrate such as polyvinyl chloride, or a hologram in addition to the image pattern. And those having so-called OVD (Optical Variable Device) images represented by images using diffraction gratings or optical thin films using multilayer interference (effects such as color shift can be obtained by optical design) are known. It has been.

  These OVD techniques for holograms and diffraction gratings require advanced manufacturing techniques and are difficult to duplicate, and thus have been used for cards such as credit cards, ID cards, and prepaid cards as effective forgery prevention means. Furthermore, due to its high decorativeness, it is often used for packaging materials, books, pamphlets, POPs and the like. As a means for adhering these OVDs to articles, a method of transferring and forming using a transfer foil has been conventionally employed.

  This type of transfer has a structure in which a release layer, a relief layer for forming an image pattern of a hologram or diffraction grating, a reflective layer formed by a known thin film forming means, and an adhesive layer are sequentially bonded on a support. It has been known. These OVD patterns (holograms and diffraction grating patterns) engraved on the transfer foil are replicated in large quantities by a well-known method in which a minute uneven pattern is replicated on a nickel-type press plate and heated to the relief layer.

In addition, the reflective layer can be formed as a transparent hologram or a transparent diffraction grating by forming a transparent material having a different refractive index by a known thin film forming means such as a vacuum deposition method (hereinafter referred to as a transparent thin film layer). This is a known technique. In this case, it is clear from an optical point of view that the greater the difference in refractive index between the relief layer and the transparent thin film layer, the greater the reflectance. However, in general, there is a relationship of (refractive index of relief layer) <(refractive index of transparent thin film layer).

  The hologram or diffraction grating structure thus obtained is used as a means for preventing counterfeiting, such as credit cards, cash cards, membership cards, employee cards, prepaid cards, driver's licenses, and other cards, gift certificates, and gift certificates. In addition to various paper vouchers such as stock certificates, application forms, receipts, copy slips, and other booklets such as passports, passbooks, and pension notebooks, covers such as covers and panels such as books and notebooks, etc. It is used by sticking to a part or the whole.

  In addition, the whole described in the present invention is a conceptual meaning, regardless of a pattern, a pattern, or the like, a spot shape, a stripe shape, a thing stuck on a lattice, a regular shape, an irregular shape halftone dot Also included are those stuck with dots in the shape of a circle.

  Such an OVD transfer foil has a sufficient function as an anti-counterfeiting effect, but is formed by thermally transferring an OVD transfer layer on the image after forming an image such as a face photograph like a passport. At present, when the forgery technology has been developed, there is a possibility that the transfer layer is once removed by some method, the image data or the like is altered, and then the OVD transfer foil is placed again.

  In addition, there is a possibility that image data may be falsified by selecting a person whose face shape / atmosphere is similar to the face photo of an authentication medium such as a stolen passport and pasting the printed photo over the face. .

  In addition, in consideration of the situation in which the sublimation transfer method, the heat-melting transfer ribbon method, or the electrophotographic method, as a means for forming image information such as a facial photograph, is now widely used, an image forming unit It is becoming difficult to say that it is always difficult to form a new image in the area after removing the image.

  In order to solve the above problems, a method of putting a plurality of personally identifying information such as a face photograph, for example, recording digital watermark information in a face photograph and storing the information in an IC chip in the same medium There is a method for authentication by collating digital watermark information with information on an IC chip (Patent Document 4).

  Also, there is a method of authenticating by converting the feature points of the facial photo information into numerical values, converting the values into a two-dimensional code, printing them on the same medium, and comparing the data of the two-dimensional code with the feature points of the facial photo ( Patent Document 5).

  However, the above method requires a dedicated decoder for reading a face photograph, an IC chip, or a two-dimensional code, and there is a problem that authentication cannot be performed by anyone other than the person who owns the reading device and the decoder.

  As another method, a direct thermal transfer method using a hologram ribbon that forms image information such as a face photograph with a hologram or a diffraction grating is known. As a result, the hologram image must be altered simultaneously with the alteration of the face photograph or the like by the color image, so that the alteration can be made more difficult (Patent Documents 6 and 7).

However, when forming image information that requires high resolution such as a face photograph by the above method, the hologram ribbon is inferior in temperature detection performance as compared to the ink ribbon, so fine dots are difficult to strike, and the sharpness of the hologram ribbon material Transferability is important.

  One solution is to add fine particles to the hologram ribbon to increase the sharpness. The scattering of the fine particles causes some turbidity on the hologram ribbon, and the printed part becomes cloudy at an angle at which diffracted light does not exit. There is a possibility of being visually recognized. In addition, when image information such as a facial photograph is formed by partially overlapping hologram ribbons with different spatial frequencies, the image is transferred only with the portion where the hologram ribbons with different spatial frequencies are transferred and the hologram ribbon with one type of spatial frequency. A difference in turbidity may occur between the portions that have been transferred and the visibility of the portions that are transferred in an overlapping manner may be reduced.

JP 2002-226740 A JP 49-131142 A JP 2006-123174 A Japanese Unexamined Patent Publication No. 2001-126046 Japanese Laid-Open Patent Publication No. 2004-70532 JP 10-049647 A Japanese Patent Application No. 8-24226

  The present invention has been made in view of the above-mentioned problems of the prior art, and aims to improve the quality of an image display body that requires high security, such as a passport, a visa, or various cards. An object of the present invention is to provide an image display body that improves visibility, has anti-counterfeiting, tampering, or alteration prevention performance, and can easily find an suspicious product by observation even if it is fraudulent. And

As means for solving the above problems, the invention according to claim 1 is an image display body obtained by thermally transferring a hologram transfer foil as a plurality of image cells to a substrate to be transferred, the image display body. Is
At least a base material and a release layer, an image receiving layer, an adhesive layer, a transparent reflection layer, and a hologram layer are laminated on one surface of the base material,
The hologram layer has two or more different relief structure forming portions, the content ρ of the inorganic fine particles contained in the adhesive layer is greater than 0.02 and less than 1.0, and The image display body is characterized in that the transmittance η of the image display body is smaller than a value obtained by adding 0.15 to 1.8 times the turbidity ε of the adhesive layer.

In the invention according to claim 2, the shape of the plurality of image cells is
The image display body according to claim 1, wherein the image display body has a minute dot shape or a minute width line shape.

According to a third aspect of the present invention, a release layer and a hologram forming layer made of a thermoplastic resin are laminated on one surface of a substrate, and a relief structure of a hologram having a different spatial frequency and diffraction angle is thermoformed, Laminate a transparent reflective layer,
Alternatively, a release layer, a hologram forming layer made of a thermoplastic resin, and a transparent reflective layer are laminated on one surface of the substrate, and a relief structure of a hologram having a different spatial frequency and diffraction angle is thermoformed,
Further, the content ρ of the inorganic fine particles contained is greater than 0.02 and less than 1.0, and the transmittance η of the image display body is 1.8 times the turbidity ε of the adhesive layer. Laminating an adhesive layer having a value smaller than the value obtained by adding 0.15,
A plurality of hologram transfer foils formed
A method for producing an image display body, wherein the image cell is formed by thermal transfer to a substrate to be transferred a plurality of times as image cells having a minute dot shape or a line shape having a minute width.

  According to the invention described in claim 1 or 2, it is possible to provide an image display body having individual information regarding the owner, which is formed from the relief structure portion of the hologram layer. Since this image display body is obtained by thermal transfer of the transfer foil, it can be produced faster and cheaper than that produced by photographing or drawing. Here, the adhesive layer to which inorganic fine particles have been added can improve the cutability and transferability of the transfer portion of the hologram transfer foil, so that a high-resolution image can be created. Further, the positive image and the negative image of the display image are transferred to each of the two or more different relief structure forming portions so that the visibility of the image display body having individual information is not lowered by mixing inorganic fine particles. Thus, since an image display body in which the entire surface of the image is formed of the same layer can be obtained, a high-quality image can be created.

  According to the third aspect of the present invention, it is possible to provide a method for producing an image display body having individual information regarding the owner, which is formed from the relief structure portion of the hologram layer.

1 is a plan view schematically showing an information medium according to an aspect of the present invention. FIG. 2 is an enlarged plan view showing a part of an image display body that can be thermally transferred to the information medium shown in FIG. 1. It is sectional drawing along the AA line of the image display body shown in FIG. It is the top view which expanded and showed other one part of the image display body which can be thermally transferred to the information medium shown in FIG. FIG. 5 is a cross-sectional view taken along line BB of the image display unit illustrated in FIG. 4. FIG. 6 is a plan view schematically showing an example of a hologram transfer foil that can be used for manufacturing the image display body shown in FIGS. 2 to 5. FIG. 7 is a cross-sectional view schematically showing an example of the hologram transfer foil shown in FIG. 6. It is sectional drawing which showed schematically the transfer method which transfers the hologram transfer foil shown in FIG. 7 to a to-be-transferred base material, and obtains an image display body. It is sectional drawing which showed roughly an example of the image display body produced with the transfer method shown in FIG. FIG. 10 is a cross-sectional conceptual diagram illustrating an example of an information medium produced by transferring the image display body illustrated in FIG. 9.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, the same reference numerals are given to the constituent elements that exhibit the same or similar functions of the present invention throughout all the drawings, and the overlapping description is omitted.

  FIG. 1 is a plan view schematically showing an information medium according to an aspect of the present invention.

  An information medium 100 shown in FIG. 1 is a booklet such as a passport. FIG. 1 depicts the open state.

In FIG. 1, an information medium 100 displays an image 1a, an image 1b, and a character image 2. The image 1a and the character image 2 are images that are displayed using light absorption. Specifically, the image 1a and the character image 2 are images that are visible when illuminated with white light and observed with the naked eye.

  The image 1a and the character image 2 can be comprised with dye and a pigment, for example. In this case, for the formation of the images 1a and 2, a thermal transfer recording method using a thermal head, an ink jet recording method, an electrophotographic method, or a combination of two or more of them can be used. It is also possible to form the image 1a and the character image 2 by forming a layer and drawing on this layer with a laser beam. Also, a combination of these methods can be used. At least a part of the character image 2 may be formed by a thermal transfer recording method using a hot stamp, a printing method, or a combination thereof.

  The image 1b is an image displayed by the relief structure of the hologram and / or diffraction grating. The image 1b is formed, for example, by performing thermal transfer recording using a thermal head and thermal transfer recording using a hot stamp or a heat roll in this order.

  The images 1a and 1b include face images of the same person. The face image included in the image 1a and the face image included in the image 1b may have the same or different dimensions. Each of the image 1a and the image 1b may include other biological information instead of the face image, and may further include biological information other than the face image in addition to the face image.

  The image 1b may include non-biological personal information instead of the biological information, and may further include non-biological personal information in addition to the biological information. Further, the image 1b may include non-personal information instead of personal information, and may further include non-personal information in addition to the personal information. The image 2 includes non-biological personal information, personal information, and non-personal information. The image 2 constitutes, for example, one or more of characters, symbols, symbols, and marks.

  Next, the structure of an image display body that can be thermally transferred to the information medium 100 will be described with reference to FIGS. FIG. 2 is an enlarged plan view showing a part of an image display body that can be thermally transferred to the information medium 100 shown in FIG. FIG. 3 is a cross-sectional view taken along line AA of the image display body 300 shown in FIG. 4 is an enlarged plan view showing another part of the image display body that can be thermally transferred to the information medium shown in FIG. FIG. 5 is a cross-sectional view taken along line BB of the image display unit shown in FIG.

  The image cell 32a, the image cell 32b, and the image cell 32c include a relief structure of a hologram or a diffraction grating. The structure and formation method of the image cell 32a, the image cell 32b, and the image cell 32c will be described in detail later. As shown in FIGS. 2 to 5, the image cell 32a and the image cell 32c have a pattern shape corresponding to the image 1b. In addition, as shown in FIGS. 2 to 5, the image cell 32 b fills the area other than the portion where the image cell 32 a and the image cell 32 c are formed. That is, it has a pattern shape corresponding to the negative image of the image 1b.

  The release layer 33 covers the image cell 32a, the image cell 32b, and the image cell 32c. The release layer 33 has light transmittance and is typically transparent. The release layer 33 is made of, for example, a resin.

  Next, the structure of the image cell 32a, the image cell 32b, and the image cell 32c, the method for manufacturing the image display body 300, and the method for manufacturing the information medium 100 will be described with reference to FIGS.

FIG. 6 is a plan view schematically showing an example of a hologram ribbon that can be used for manufacturing the image display body shown in FIGS. FIG. 7 is a cross-sectional view schematically showing an example of the hologram transfer foil shown in FIG. FIG. 8 is a cross-sectional view schematically showing a transfer method for transferring the hologram transfer foil shown in FIG. 7 to a transfer substrate to obtain an image display body. FIG. 9 is a cross-sectional view schematically showing an example of an image display body produced by the transfer method shown in FIG.

  The hologram transfer foil 200 shown in FIGS. 6 to 7 is, for example, a transfer ribbon. The hologram transfer foil 200 includes a base material 21, a release layer 23, a hologram layer 24, a transparent reflection layer 25, and an adhesive layer 26 containing inorganic fine particles.

  The base material 21 is a resin film or a sheet, for example. The base material 21 is made of, for example, a plastic material such as polyethylene terephthalate (PET), polypropylene (PP), polycarbonate (PC), polymethyl methacrylate (PMMA), or polyethylene (PE).

  The release layer 23 is for easily peeling the base material 21, and is formed on the surface of the base material 21. The release layer 23 may be made of any material that can be easily peeled off from the base material 21. For example, polycarbonate resin, acrylic resin, fluorine acrylic resin, silicone acrylic resin, epoxy acrylate resin, polystyrene resin, cycloolefin Polymers, methylstyrene resins, fluorene resins, PET, polypropylene, polyethylene terephthalate resins, polyacetal resins, and other thermoplastic resins with addition of silicone and fluorine additives, fluorine acrylic resins, silicone acrylic resins, etc. Is mentioned. The release layer 23 has light transmissivity and is typically transparent.

  The hologram layer 24 is formed on one surface of the hologram transfer foil 200 via a release layer 23. Examples of the material of the hologram layer 24 include polycarbonate resin, acrylic resin, fluorine acrylic resin, silicone acrylic resin, epoxy acrylate resin, polystyrene resin, cycloolefin polymer, methylstyrene resin, fluorene resin, PET, polypropylene, and the like. A photo-curable resin, or a thermosetting resin such as acrylonitrile styrene copolymer resin, phenol resin, melamine resin, urea resin, alkyd resin, or thermoplastic resin such as polypropylene resin, polyethylene terephthalate resin, polyacetal resin, etc. The hologram layer 24 can be formed on the surface of the release layer 23 by molding and curing the above resin into a desired structure.

  In addition, all the hardened | cured materials of the resin which form the hologram layer 24 are light-transmitting, and a refractive index is generally about 1.5. Further, the film thickness of the hologram layer 24 is preferably as thin as possible in order to improve heat resistance, foil breakage and thermal transfer properties, and is preferably 1.5 μm or less.

The hologram layer 24 includes a relief structure forming portion H1, a relief structure forming portion H2, and a relief structure forming portion H3 of a hologram and / or diffraction grating. As parameters of the relief structure forming portion H1, the relief structure forming portion H2, and the relief structure forming portion H3,
(1) Spatial frequency of relief structure (pitch of grid lines: number of grid lines per unit length)
(2) Relief structure direction (lattice line direction)
According to (1) above, the color in which the image cell appears to shine changes, and in accordance with (2) above, the direction in which the image cell appears to shine changes.

In the hologram transfer foil of the present invention, for example, as shown in FIG. 6, the relief structure forming portion H1, the relief structure non-forming portion H2 in which no relief structure is recorded, and the relief structure forming portion H1 are only the above (1). The relief structure forming portion H2 with the change in the height and the relief structure formation portion H3 are composed of the hologram layer 24 in which the relief structure formation portions H3 with only the change (2) are arranged in order. At this time, the color that can be seen at a fixed point is different between the relief structure forming portion H1 and the relief structure forming portion H2, and the visible angle is different between the relief structure forming portion H1, the relief structure forming portion H2, and the relief structure forming portion H3. Although not shown, for example, if three types of relief structure forming portions having different spatial frequencies of the relief structure are provided so that the color appearance at a fixed point is three colors of R, G, and B, a full color An image can be obtained.

  The transparent reflection layer 25 reflects light incident on the hologram layer 24 and is formed on the surface of the hologram layer 24. The transparent reflective layer 25 can be omitted, but the visibility of the image displayed by the relief structure forming portion is improved by providing the transparent reflective layer.

The transparent reflection layer 25 may be either a transparent film or a metal film. When the transparent reflection layer 25 is made of a transparent film, the dielectric layer, the dielectric multilayer film, or the constant refraction having a refractive index different from that of the hologram layer 24 is used. It is desirable to use an index material as the material for the transparent coating. In particular, it is preferable to use ZnS, TiO ₂ , PbTiO ₂ , ZrO, ZnTe, PbCrO ₄ or the like having a refractive index of 2.0 or more. This is because if the difference in refractive index from the hologram layer 24 is small, the visual effect of the diffracted light by the relief structure forming portion of the hologram layer 24 is weakened. Specifically, the difference in refractive index between the hologram layer 24 and the transparent film is preferably at least 0.5. Moreover, it is preferable that the film pressure of a transparent film is about 50 nm-100 nm.

  When the transparent reflective layer 25 is made of a metal film, a simple substance selected from chromium, nickel, aluminum, iron, titanium, silver, gold, copper, a mixture thereof, an alloy, or the like can be used. Also here, the film thickness is preferably 50 nm to 100 nm.

  The adhesive layer 26 is for adhering the transparent reflective layer 25 onto the surface of the substrate 301 to be transferred, and is formed on the surface of the hologram layer and the transparent reflective layer 25. Examples of the material of the adhesive layer 26 include thermoplastic resins such as polypropylene resin, polyethylene terephthalate resin, polyacetal resin, and polyester resin, and are obtained by adding inorganic fine particles to these resins.

  Examples of the inorganic fine particles to be added include silica. The inorganic fine particles are preferably added at a solid content ratio of 10 to 40 with respect to the solvent. The layer thickness of the adhesive layer 26 is preferably 0.2 to 1.0 μm.

  Since the hologram transfer foil 200 is transferred with a dot having a very small area or a line shape having a very small width, a foil cutting property is required. The reason for adding inorganic fine particles is to improve the cutting ability of the foil. In addition, the addition of inorganic fine particles improves the adhesion between the image cell transferred first and the image cell transferred later when transferring the image cell over the image cell as shown in FIGS. It also has an effect to make.

  FIG. 8 shows a method for obtaining the image display body by transferring the hologram transfer foil 200 onto the surface of the substrate 301 to be transferred. When the image display body 300 as shown in FIG. 8B is obtained from the hologram transfer foil 200 shown in FIG. 7, the hologram transfer foil 200 is placed on the surface of the substrate 301 to be transferred as shown in FIG. Then, the base material 21 of the hologram transfer foil 200 is placed on the upper side, and the hot pressure 15 is applied to the upper surface of the hologram transfer foil 200 between the broken lines shown in the figure.

  Thereafter, when a portion to which the thermal pressure 15 is not applied is peeled off from the transfer base material 301, peeling occurs between the substrate 21 and the release layer 23 in the portion to which the thermal pressure 15 is applied. As a result, as shown in FIG. 8B, only the hologram transfer foil 200 to which the thermal pressure 15 is applied is transferred onto the surface of the substrate to be transferred 301. The image display body 300 having the hologram transfer foil 200 transferred to the position can be obtained.

In manufacturing the image display body 300, for example, first, a human face is photographed using an imaging device. Alternatively, a face image or character information is read from the print. Thereby, image information is obtained as electronic information.

  Next, a transfer substrate 301 shown in FIG. 9 is prepared. This transferred substrate 301 includes a substrate 31, a release layer 33 and an image receiving layer 37. As the said base material 31, what was illustrated about the base material 21 of FIG. 7, for example can be used.

  The peeling layer 33 is for facilitating peeling of the peeling layer 33 and the image cells 32a, 32b, and 32c from the support 31. As the release layer 33, for example, those exemplified for the release layer 23 of FIG. 7 can be used.

  The image receiving layer 37 may include at least one of a hologram and a diffraction grating as a diffraction structure. For example, a relief structure as a diffractive structure may be provided on the surface of the image receiving layer 37. Thus, the image displayed by the diffraction structure and the image displayed by the image cell 32a and the image cell 32c can be overlapped or arranged.

  The transferred substrate 301 may further include a patterned metal reflection layer, for example, an opaque metal reflection layer. For example, a patterned metal reflective layer is provided on the image receiving layer 37 between the peeling layer 33 and the image receiving layer 37, and halftone dots, lines, other figures, or combinations thereof are displayed on the metal reflective layer. May be. Such a pattern can be used for authenticity determination of the image display body 300 or the information medium 100, for example.

  Next, image cells 32a, 32b, and 32c having a pattern corresponding to the previous face image or character information are formed on the substrate 301 to be transferred. Specifically, based on the previous image information, the image cells 32a, 32b and 32c are thermally transferred from the hologram transfer foil 200 shown in FIGS. 6 and 7 onto the image receiving layer 37 shown in FIG. This thermal transfer is performed using a thermal head so that the portion thermally transferred from the hologram transfer foil 200 to the image receiving layer 37 as an image cell has a pattern corresponding to the previous face image or character information.

  Here, the relief structure forming portion H1, the relief structure forming portion H2, and the relief structure forming portion H3 in FIGS. 6 and 7 correspond to the image cell 32a, the image cell 32b, and the image cell 32c, respectively.

  Since the image cell 32a, the image cell 32b, and the image cell 32c thus obtained are formed by thermal transfer using a thermal head, typically, a plurality of dot shapes or line shapes are used as shown in FIGS. Consists of. Each center of these dot-like portions or linear portions is located on a lattice point of a virtual planar lattice indicated by a broken line in FIGS.

  In FIG. 2 and FIG. 4, the previous planar lattice is a square lattice, but the planar lattice may be other lattices such as a triangular lattice and a rectangular lattice.

  The diameter of the dot-shaped portion or the line width of the linear portion is, for example, in the range of 0.085 to 0.508 mm (about 300 to about 50 dots per inch), and typically 0.085 to 0.169 mm ( About 300 to about 150 dots per inch). When this dimension is increased, when a face image is displayed in the image cell 12a, the image cell 12a ', the image cell 12b, and the image cell 12b', it becomes difficult to display a high-definition image. If this dimension is reduced, the reproducibility of the pattern shape of the image cell is lowered.

As shown in the description of the adhesive layer 26 in FIGS. 6 to 7, the adhesive layer 36 shown in FIG. 9 is obtained by adding inorganic fine particles to a resin as a main agent. The addition of the inorganic fine particles improves the cutability and adhesion of the foil, while the fine particles themselves scatter light, resulting in turbidity in the hologram transfer foil 200. The turbidity of the hologram transfer foil 200 is greatly reduced by transferring the image cell to the substrate 301 to be transferred. However, the turbidity of the hologram transfer foil 200 is not completely transparent. There is a difference. This minute difference does not affect the visibility at the angle at which the diffracted light is emitted from the image cell, but when observed at an angle at which the diffracted light is not emitted, only the portion to which the image cell is transferred becomes thin and turbid. It may appear and the visibility of the image display body 300 may be reduced.

  Therefore, in order to improve the above, in FIG. 9, the image cell 32b is transferred at a portion where the image cell 32a is not transferred, that is, at the previous face image or the negative pattern portion of the character information. As a result, the image information expressed by the transfer layer first layer on the upper surface of the image receiving layer 37 of the transfer target 301 has a uniform transmittance as a whole, and thus avoids a decrease in visibility due to the observation angle of the image display body. be able to.

  Further, instead of the image cell 32b, an image cell having a relief structure having parameters (spatial frequency or direction, or spatial frequency and direction) different from the image 32a may be arranged in the image cell 32b portion of FIG. As a result, the image information expressed by the transfer layer first layer on the upper surface of the image receiving layer 37 of the transfer target 301 not only has a uniform transmittance as a whole, but also changes the observation angle of the image to be displayed. While the pozy negative image is viewed and the visibility is improved, the anti-counterfeiting property can also be improved.

  Further, as shown in FIG. 9, the image display body in which the transfer portion first layer 320 is filled with the image cell 32a and the image cell 32b is used as a transfer portion second layer 321, which is different from the image cell 32a (spatial frequency and The image cell 32c having (or direction) may be transferred. Although not shown, an image cell having a relief structure having parameters (spatial frequency and / or direction) different from those of the image 32a and the image 32c in a portion where the image cell 32 of the transfer portion second layer 321 is not disposed. May be arranged, or the image cell 32b may be arranged.

  It is also possible to transfer a plurality of additional layers on the transfer portion second layer 321. At this time, for example, image cells of different spatial frequencies can be overlapped so that the color appearance at a fixed point is three colors of R, G, and B. In this case, a full-color image can be obtained, and the visibility of the display image is further improved.

  When a large number of image cells are stacked, a difference in transmittance between a portion where a large number of image cells overlap and a portion where the image cells are not transferred increases, which affects visibility. In order to improve this, at least in the first layer of the transfer portion, from the image cell / or relief structure non-forming portion having a parameter different from that in the portion other than the image cell arranged corresponding to the previous image information or character information. It is effective to arrange the image cells so that the entire layer has a uniform transmittance.

  As shown in the description of the adhesive layer 26 in FIGS. 6 to 7, the amount of inorganic fine particles added to the adhesive layer 36 is set to a solid content ratio of 10 to 40 with respect to the solvent. If the amount of inorganic fine particles added is 10 or less, the holographic transfer foil 200 has insufficient foil cutting properties. If the amount of the inorganic fine particles added exceeds 40, the turbidity is clearly confirmed even when the hologram transfer foil is transferred to the substrate to be transferred, and as a result, the visibility of the image display body is significantly reduced.

Here, the value obtained by dividing the solid content ratio of the inorganic fine particles by 100 is defined as the content ρ of the inorganic fine particles. The total turbidity ε of the adhesive layer 26 is obtained by integrating the total thickness of the adhesive layer 26 (the thickness of the adhesive layer × the number of layers in the transfer portion) with the content ρ of the inorganic particles.
Further, a value obtained by measuring a portion of the image display body 300 obtained by transferring the hologram transfer foil 200 to the transfer substrate, in which the relief structure is not formed, specifically, using a spectroscopic color change colorimeter, An average value obtained by dividing the spectral luminance value when the incident light angle is 45 degrees and the light receiver is received at an angle of 0 degrees by the spectral luminance value of the irradiation light source is defined as the transmittance η of the image display body.

The turbidity ε of the adhesive layer and the transmittance η of the image display body are in a proportional relationship. Here, the transmittance η of the image display body is a value smaller than the turbidity ε × 1.8 + 0.15 of the adhesive layer. Become. Further, the turbidity ε of the adhesive layer is set to be larger than 0.02 and smaller than 1.0. For example, when the amount of inorganic fine particles added is 10 and the total thickness of the adhesive layer is 0.2 μm (adhesive layer = 0.2 μm and the number of layers is 1), the turbidity ε = 0. 02. Further, for example, when the amount of inorganic fine particles added is 40 and the total thickness of the adhesive layer is 2.4 μm (adhesive layer = 0.6 μm and the number of layers is 4), the turbidity of the adhesive layer ε = 0.96.
Next, an information medium produced by thermal transfer of the image display body will be described with reference to FIG.

  FIG. 10 is a cross-sectional view schematically showing an example of an information medium produced by transferring the image display body 300 shown in FIG.

  The information medium 100 shown in FIG. 10 is obtained by thermally transferring the image display body 300 shown in FIG. 9 from the base material 31 to the base material 11. For this thermal transfer, for example, a hot stamp is used. Instead of thermal transfer using a hot stamp, thermal transfer using a thermal roll or a thermal head may be performed. The information medium 100 is obtained as described above.

  An adhesive anchor layer may be formed on the base material 11 in order to increase the adhesive strength.

  When it is difficult to adhere the information medium 100 to the base material 31 with high adhesive strength, the information medium 100 may be thermally transferred to the base material 11 through an adhesive layer. For example, an adhesive ribbon may be used. If this is used, the adhesive strength between the information medium 100 and the substrate 11 can be increased. According to this method, as shown in FIG. 10, a structure in which the adhesive layer 46 is interposed between the image cell and the substrate 11 is obtained.

  The information medium 100 as a passport has been exemplified above, but the technology described above for the information medium 100 can also be applied to other personal authentication media. For example, this technology can be applied to various cards such as a visa and an ID card.

  The material of the base material to which the image display body 300 is attached may be other than paper. For example, the base material to which the image display body 300 is attached may be a plastic substrate, a metal substrate, a ceramic substrate, or a glass substrate.

  When the base material to which the image display body 300 is attached is, for example, a base material having a small surface roughness, the portion other than the image cell forming the display image shown in FIG. The method of filling with image cells having different image cells / or relief structure non-formed portions is particularly effective. This is because the difference in turbidity due to the presence or absence of image cells is easily visible on a substrate having a small surface roughness.

<Example 1: Production of image display body D1>
A hologram transfer foil 200 was manufactured as follows. First, a polyethylene terephthalate film having a thickness of 12 μm was prepared as the base material 21. On this base material 21, the peeling layer 23 and the thermoplastic resin layer were formed in this order using the gravure coater, and these were dried in oven. An acrylic resin was used as the material of the release layer 23, and an acrylic polyol was used as the material of the thermoplastic resin layer. The film thickness after drying of the peeling layer 23 and the thermoplastic resin layer was 0.6 μm and 0.7 μm, respectively.

Next, two types of relief structures as holograms were formed on the surface of the thermoplastic resin by hot pressing using a roll embossing device. At this time, the depths of the formed diffraction structures were both about 100 nm, the spatial frequency was the same at 1000 lines / mm, and the grating angles were 0 degrees and 90 degrees, respectively.
Next, a transparent reflective layer 25 made of zinc sulfide was formed on the relief structure of the thermoplastic resin by vapor deposition. The film thickness of the transparent reflective layer 25 was 50 nm.

  Further, an adhesive layer 26 in which silica was added as inorganic fine particles to a polyester resin, which is a thermoplastic resin, was formed on the transparent reflective layer using a gravure coater. The amount of silica added was 20 in the solid content ratio with respect to the solvent, and the film thickness of the adhesive layer 26 was 0.6 μm. That is, the content ρ of the inorganic fine particles contained in the adhesive layer was set to 0.12, and the hologram transfer foil 200 was completed.

  Next, the image forming body 300 shown in FIGS. 2 to 3 was manufactured by the following method. First, a polyethylene terephthalate film having a thickness of 25 μm was prepared as the base material 31. On this base material 31, the peeling layer 33 and the image receiving layer 37 were formed in this order using the gravure coater, and these were dried in oven. An acrylic resin was used as the material for the release layer 33, and an acrylic polyol was used as the material for the image receiving layer 38. The film thickness after drying of the peeling layer 33 and the image receiving layer 38 was 1.2 μm and 1.0 μm, respectively.

  Next, by performing thermal transfer using a 300 dpi thermal head, an image cell 32b having a spatial frequency of 1000 lines / mm and a lattice angle of 0 degrees and an image cell 32c having a spatial frequency of 1000 lines / mm and a lattice angle of 90 degrees are formed on the basis. The material 21 was transferred onto the image receiving layer 37. In the transfer of the image cell, the image information is displayed in the image cell 32b, and the information that becomes the negative image of the image information is displayed in the image cell 32c. At this time, the transmittance η of the transferred portions of the image cells 32b and 32c was 0.3 to 0.35. The image display body produced as described above is referred to as “image display body D1”.

<Example 2: Production of image display body D2>
A hologram transfer foil 200 was manufactured as follows. First, a polyethylene terephthalate film having a thickness of 12 μm was prepared as the base material 21. On this base material 21, the peeling layer 23 and the thermoplastic resin layer were formed in this order using the gravure coater, and these were dried in oven. An acrylic resin was used as the material of the release layer 23, and an acrylic polyol was used as the material of the thermoplastic resin layer. The film thickness after drying of the peeling layer 23 and the thermoplastic resin layer was 0.6 μm and 0.7 μm, respectively.

Next, three types of relief structures as holograms were formed on the surface of the thermoplastic resin by hot pressing using a roll embossing device. At this time, the depths of the formed diffraction structures were all about 100 nm, and the spatial frequencies and angles were 500 lines / mm · 0 degrees, 1000 lines / mm · 0 degrees, and 500 lines / mm · 90 degrees, respectively. Moreover, the part which did not form the relief structure only by the same area as the relief structure was provided in the surface of the same thermoplastic resin.
Next, a transparent reflective layer 25 made of zinc sulfide was formed on the relief structure of the thermoplastic resin by vapor deposition. The film thickness of the transparent reflective layer 25 was 50 nm.

Further, an adhesive layer 26 in which silica was added as inorganic fine particles to a polyester resin, which is a thermoplastic resin, was formed on the transparent reflective layer using a gravure coater. The amount of silica added was 20 in terms of solid content with respect to the solvent, the thickness of the adhesive layer 26 was 0.6 μm, and the content ρ of the inorganic fine particles contained in the adhesive layer was 0.12. The hologram transfer foil 200 was completed as described above.

  Next, the image forming body 300 shown in FIG. 9 was manufactured by the following method. First, a polyethylene terephthalate film having a thickness of 25 μm was prepared as the base material 31. On this base material 31, the peeling layer 33 and the image receiving layer 37 were formed in this order using the gravure coater, and these were dried in oven. An acrylic resin was used as the material for the release layer 33, and an acrylic polyol was used as the material for the image receiving layer 38. The film thickness after drying of the peeling layer 33 and the image receiving layer 38 was 1.2 μm and 1.0 μm, respectively.

  Next, by performing thermal transfer using a 300 dpi thermal head, an image cell 32a having a spatial frequency of 500 lines / mm and a lattice angle of 0 degrees, an image cell 32b having a spatial frequency of 1000 lines / mm and a lattice angle of 0 degrees, and a spatial frequency The image cells 32c having 500 lines / mm and a lattice angle of 90 degrees were transferred from the substrate 21 onto the image receiving layer 37. In the transfer of the image cell, the character information of the image information is displayed in the image cell 32a, and then the negative image of the character information is displayed in the image cell 32c to obtain the transfer layer first layer. Is displayed in the image cell 32b. At this time, the transmittance η of the portion where the image cells 32a and 32b are transferred and overlapped and the portion where the image cells 32c and 32b are transferred and transferred are 0.4 to 0.5. The image display body produced as described above is referred to as “image display body D2”.

<Comparative Example 1: Production of image display body D3>
A hologram transfer foil 200 was manufactured as follows. First, a polyethylene terephthalate film having a thickness of 12 μm was prepared as the base material 21. On this base material 21, the peeling layer 23 and the thermoplastic resin layer were formed in this order using the gravure coater, and these were dried in oven. An acrylic resin was used as the material of the release layer 23, and an acrylic polyol was used as the material of the thermoplastic resin layer. The film thickness after drying of the peeling layer 23 and the thermoplastic resin layer was 0.6 μm and 0.7 μm, respectively.

  Next, two types of relief structures as holograms were formed on the surface of the thermoplastic resin by hot pressing using a roll embossing device. At this time, the depths of the formed diffraction structures were both about 100 nm, the spatial frequencies were 500 lines / mm and 1000 lines / mm, respectively, and the grating angles were 0 degrees and the same. Next, a transparent reflective layer 25 made of zinc sulfide was formed on the relief structure of the thermoplastic resin by vapor deposition. The film thickness of the transparent reflective layer 25 was 50 nm.

  Further, an adhesive layer 26 in which silica was added as inorganic fine particles to a polyester resin, which is a thermoplastic resin, was formed on the transparent reflective layer using a gravure coater. The amount of silica added was 20 in the solid content ratio with respect to the solvent, and the film thickness of the adhesive layer 26 was 0.6 μm. That is, the content ρ of the inorganic fine particles contained in the adhesive layer was set to 0.12. The hologram transfer foil 200 was completed as described above.

  Next, an image forming body 300 as a comparative example was manufactured by the following method.

  First, a polyethylene terephthalate film having a thickness of 25 μm was prepared as the base material 31. On this base material 31, the peeling layer 33 and the image receiving layer 37 were formed in this order using the gravure coater, and these were dried in oven. An acrylic resin was used as the material for the release layer 33, and an acrylic polyol was used as the material for the image receiving layer 38. The film thickness after drying of the peeling layer 33 and the image receiving layer 38 was 1.2 μm and 1.0 μm, respectively.

Next, by performing thermal transfer using a 300 dpi thermal head, image cells having different parameters were transferred from the substrate 21 onto the image receiving layer 37. In the transfer of the image cell, the character information of the image information is displayed in the image cell 32a having a spatial frequency of 500 lines / mm
Next, the face image of personal information was displayed in the image cell 32b with a spatial frequency of 1000 lines / mm. At this time, the transmittance η of the portion where the image cells 32a and 32b are transferred in an overlapping manner is 0.4 to 0.5. Further, the transmittance η of the portion where the image cells 32c and 32b are not printed is 0.15. The image display body produced as described above is referred to as “image display body D3”.

  Table 1 compares the image display body D1, the image display body D2, and the image display body D3.

When the image display body D1 manufactured as described above is observed at an angle at which diffracted light is not emitted, the difference between the image display portion and the other portions is not observed, and the image display body D2 is rotated by 90 degrees. The negative image of the image display portion was observed by emitting diffracted light, and an image display body with good visibility was obtained.

  Further, when the image display body D2 and the image display body D3 were compared, a difference in visibility occurred in the portion where the character information was formed. In the image display body D3, the character information was observed to be slightly turbid at the angle at which the face image is observed. However, the image display body D2 has no appearance of character information due to turbidity, and has better visibility than the image display body D3. An image display body was obtained.

DESCRIPTION OF SYMBOLS 1a ... Image 1b ... Image 2 ... Character image 11 ... Base material 15 ... Hot pressure 16 ... Location where the hot pressure is applied 21 ... Base material 23 ... Release layer 24 ... Hologram layer 25 ... Transparent reflective layer 26 ... Adhesive layer 31 containing inorganic fine particles ... Base material 32a ... Image cell 32b ... Image cell 32c ... Image cell 32d ...・
33 ... peeling layer 34 ... hologram layer 35 ... transparent reflective layer 36 ... adhesive layer 37 containing inorganic fine particles ... image receiving layer 46 ... adhesive layer 100 ... information medium 200 ... -Hologram transfer foil 300-Image display body 301-Transfer target substrate 320-Transfer portion first layer 321-Transfer portion second layer H1-Relief structure forming portion H2-Relief Structure forming part H3 ... Relief structure forming part

Claims (3)

An image display body obtained by thermally transferring a hologram transfer foil to a substrate to be transferred as a plurality of image cells, the image display body,
At least a base material and a release layer, an image receiving layer, an adhesive layer, a transparent reflection layer, and a hologram layer are laminated on one surface of the base material,
The hologram layer has two or more different relief structure forming portions, the content ρ of the inorganic fine particles contained in the adhesive layer is greater than 0.02 and less than 1.0, and The image display body, wherein the transmittance η of the image display body is smaller than a value obtained by adding 0.15 to 1.8 times the turbidity ε of the adhesive layer. The shape of the plurality of image cells is
The image display body according to claim 1, wherein the image display body has a minute dot shape or a line shape having a minute width. Laminating a release layer, a hologram forming layer made of a thermoplastic resin on one surface of the substrate, thermoforming a relief structure of a hologram with different spatial frequency and diffraction angle, and further laminating a transparent reflective layer,
Alternatively, a release layer, a hologram forming layer made of a thermoplastic resin, and a transparent reflective layer are laminated on one surface of the substrate, and a relief structure of a hologram having a different spatial frequency and diffraction angle is thermoformed,
Further, the content ρ of the inorganic fine particles contained is greater than 0.02 and less than 1.0, and the transmittance η of the image display body is 1.8 times the turbidity ε of the adhesive layer. Laminating an adhesive layer having a value smaller than the value obtained by adding 0.15,
A plurality of hologram transfer foils formed
A method for producing an image display body, wherein the image cell is formed by thermal transfer to a substrate to be transferred a plurality of times as image cells having a minute dot shape or a line shape having a minute width.