JP7183720B2 - Thermal transfer medium and information recording medium - Google Patents

Description

The present invention relates to a thermal transfer medium for producing an information recording medium such as a personal authentication medium represented by passports and ID cards, an information recording medium using the same, and a method of displaying the same.

Conventionally, printed materials with characters and patterns printed by various methods, especially personal authentication media such as passports and ID cards, credit cards, passbooks, and other information recording media that require security are given security and design. In order to do so, an image having a special visual effect is provided, which is said to have effects such as prevention of forgery, falsification, and forgery, and proof of authenticity.

Various methods for providing an image have been proposed, one of which is a thermal transfer recording method using a thermal transfer medium such as an ink ribbon. Thermal transfer recording methods include direct transfer, in which ink is directly transferred from a thermal transfer medium to an information recording medium, and indirect, in which ink is first transferred from the thermal transfer medium to an intermediate transfer foil and then retransferred from the intermediate transfer foil to the information recording medium. There is a transfer method, and it is widely used according to each feature.

As a method for providing an image having a special visual effect, for example, Patent Document 1 discloses a method of forming a latent image using fluorescent ink, and Patent Document 2 discloses a pattern combining a diffraction grating and a light scattering pattern. and Patent Document 3 discloses a method of forming an image with thermal transfer ink containing a pearl pigment that emits interference light.

The latent image with fluorescent ink in Patent Document 1 is formed by printing a colorless fluorescent ink containing a fluorescent material on a card using a conventional printing technique such as offset to form a latent image. It is suitable for providing a common latent image on the card base material, and is good for identifying whether the card base material is genuine or not. A printed version had to be created for each, which was not practical.

Patent document 2 proposes a method of printing individual information using a diffraction grating such as a hologram as a thermal transfer foil. In addition, by using an indirect transfer method, an optically variable element such as a hologram is provided between the transfer layers of the intermediate transfer foil to obtain anti-counterfeiting properties. However, in general, it has become relatively easy to obtain hologram transfer foil, so the anti-counterfeiting effect is still limited, and at first glance, it is replaced by something that exhibits a similar effect. However, there was also the problem that it was difficult for anyone other than a professional engineer to visually determine the authenticity of the product.

Patent Document 3 discloses a printing method for forming a second image using a pearl pigment, and discloses a technique for forming an image in the form of a thermal transfer ribbon. It is used for various decorative boxes and wrapping papers, and is generally easy to obtain.

Registered Utility Model No. 3029273 JP-A-2000-263910 JP 2004-142445 A

The present invention provides a thermal transfer medium on which a latent image can be formed with ink containing a luster pigment (pearl pigment), and an information recording medium provided with a latent image on the thermal transfer medium. A latent image can be provided in a special pattern by ink containing An object of the present invention is to provide a thermal transfer medium and an information recording medium which can provide high security.

In order to solve the above problems, the invention according to claim 1 of the present invention is
One or more thermal transfer ink layers containing pigments and at least two functional thermal transfer ink layers made of functional inks containing luster pigments are provided in a frame-sequential manner on one side of the support,
The functional thermal transfer ink layer has a functional thermal transfer ink layer A made of a functional ink A containing a bright pigment A and a functional thermal transfer ink layer B made of a functional ink B containing a bright pigment B. death,
The functional thermal transfer ink layer A and the functional thermal transfer ink layer B have the same interference color,
The thermal transfer medium is characterized in that the functional thermal transfer ink layer A and the functional thermal transfer ink layer B have different haze values.

Further, the invention according to claim 2 of the present invention is
2. The method according to claim 1, wherein the functional thermal transfer ink layer A has a haze value of 1% or more and less than 3%, and the functional thermal transfer ink layer B has a haze value of 3% or more and less than 6%. It is a thermal transfer medium.

Further, the invention according to claim 3 of the present invention is
on the substrate,
one or more thermal transfer ink layers containing pigments;
At least a functional thermal transfer ink layer A made of a functional ink A containing a bright pigment A and a functional thermal transfer ink layer B made of a functional ink B containing a bright pigment B are thermally transferred,
The functional thermal transfer ink layer A and the functional thermal transfer ink layer B have the same interference color, the functional thermal transfer ink layer A and the functional thermal transfer ink layer B have different haze values, and an overlay layer is an information recording medium laminated with
At least one image forming unit in which a predetermined display image is formed using the functional ink A and the functional ink B is provided, and the image forming unit has the functionality when viewed from a predetermined viewing angle. The information recording medium is characterized in that the same interference color exhibited by the thermal transfer ink layer A and the functional thermal transfer ink layer B can be seen, and the interference color disappears when the observation angle is changed.

Further, the invention according to claim 4 of the present invention is
4. The method according to claim 3, wherein the functional thermal transfer ink layer A has a haze value of 1% or more and less than 3%, and the functional thermal transfer ink layer B has a haze value of 3% or more and less than 6%. It is an information recording medium.

Further, the invention according to claim 5 of the present invention is
The image forming unit forms a predetermined display image using at least two types of cell patterns, a cell pattern A formed with the functional ink A and a cell pattern B formed with the functional ink B. 5. The information recording medium according to claim 3 or 4, characterized by:

Further, the invention according to claim 6 of the present invention is
A cell pattern C formed by a core dot α formed with a functional ink A and a peripheral dot β formed with a functional ink B adjacent to the core dot α and having the same area as the core dot α. ,
A cell pattern D formed of a core dot β formed with a functional ink B and a peripheral dot α formed with a functional ink A adjacent to the core dot β and having the same area as the core dot β. 5. The information recording medium according to claim 3, wherein a predetermined display image is formed by using at least two types of cell patterns.

Further, the invention according to claim 7 of the present invention is
By superimposing a convex lens array having the same pitch as the pitch at which the cell patterns are arranged on the information recording medium according to claim 6, the functional ink of the core dots α of the cell pattern C and the core dots β of the cell pattern D This is a method of displaying a cell pattern characterized by displaying only the background color of .

According to the first aspect of the present invention, there is provided a thermal transfer medium in which a functional thermal transfer ink layer is formed by functional ink A and functional ink B each containing different bright pigments, The functional thermal transfer ink layer A made of the ink A and the functional thermal transfer ink layer B made of the functional ink B exhibit the same interference color and have different haze values, and can be transferred to a recording medium or the like requiring security. When a display image is formed, when viewed from an angle exhibiting an interference color due to the effect of the bright pigment, even if patterns such as characters and images formed by the functional ink A and the functional ink B are provided as the display image, the same display image can be obtained. Since it exhibits interference color, it cannot be seen as a pattern such as characters or images. On the other hand, when viewed from different angles, the interference color disappears, and the color of the underlying portion, that is, the underlying color, looks different due to the different haze values of the functional thermal transfer ink layer A and the functional thermal transfer ink layer B. A pattern such as a predetermined character or image can be made to appear as a display image. In other words, it is possible to obtain a thermal transfer medium which can be made into a latent image or a visible image depending on the angle at which the recording medium is viewed, and which can be viewed in different ways to provide security.

According to the second aspect of the invention, it is possible to obtain a thermal transfer medium in which the difference in appearance of the base color when the interference color disappears can be suitably obtained.

According to the third aspect of the invention, the image forming portions formed using the functional ink A and the functional ink B are identical when viewed from an angle exhibiting interference colors due to the action of the bright pigment. On the other hand, when viewed from a different angle, the interference color disappears and the color of the base is visible. is different, and an information recording medium is obtained in which the formed predetermined display image appears to float. That is, the information recording medium can be obtained as a latent image or a visible image depending on the angle at which the recording medium is viewed, and can be viewed in different ways depending on the angle at which the recording medium is viewed.

According to the fourth aspect of the invention, it is possible to obtain an information recording medium in which the difference in appearance of the base color when the interference color disappears can be suitably obtained.

Further, according to the fifth aspect of the invention, the image forming unit is formed by the cell pattern A formed with the functional ink A and the cell pattern B formed with the functional ink B, and the angle at which the interference color disappears When viewed from above, the cell pattern A and the cell pattern B look different, so that an information recording medium in which a predetermined display image appears to emerge is obtained.

According to the sixth aspect of the present invention, the image forming section forms a predetermined image using two cell patterns in which core dots and peripheral dots having the same area and having different haze values are combined. Under normal visual observation, the two types of cell patterns have the same appearance of interference color and background color, and cannot be distinguished. Characters and symbols are recorded as latent images as images formed on the cell patterns. It is possible to obtain an information recording medium on which characters, symbols, etc. can be recorded as secret information, and on which an image formed by using a convex lens array can be seen as a visible image.

According to the seventh aspect of the invention, characters and symbols recorded as latent images in the cell pattern in the image forming member of the sixth aspect are displayed by enlarging only the nuclear dot portion by means of a convex lens array. Since the appearance of the color of the base portion is different, it is possible to display the latent image in such a manner that the latent image can be easily confirmed visually.

1A and 1B are diagrams showing an example of a thermal transfer medium of the present invention; FIG. 1 is a schematic configuration diagram of an example of an indirect thermal transfer printer; FIG. 4A and 4B are diagrams showing examples of forms of a cell pattern A and a cell pattern B; FIG. FIG. 4 is a diagram showing an example of an image formed by cell pattern A and cell pattern B; FIG. 3 is a diagram illustrating how an image forming portion formed by cell patterns A and B looks. BRIEF DESCRIPTION OF THE DRAWINGS It is the figure which planarly viewed one form of the information recording medium of this invention. 1 is a cross-sectional view of one embodiment of an information recording medium of the present invention; FIG. 4A and 4B are diagrams showing examples of forms of a cell pattern C and a cell pattern D; FIG. 4A and 4B are diagrams showing examples of images formed by a cell pattern C and a cell pattern D; FIG. FIG. 4A is a plan view and a cross-sectional view of a form example of a convex lens array; FIG. 3 is a plan view showing a state in which a convex lens array is superimposed on an image pattern formed by cell patterns C and D; FIG. 4 is a schematic diagram of how an image pattern formed by cell patterns C and D looks when a convex lens array is superimposed on the image pattern. It is the figure which planarly viewed the 2nd form of the information recording medium of this invention. FIG. 4 is a cross-sectional view of a second embodiment of the information recording medium of the present invention;

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the embodiments described below. Equivalent members and the like are denoted by the same reference numerals, and description thereof may be omitted.

FIG. 1 is a diagram showing an example of the thermal transfer medium of the present invention. The thermal transfer medium 1 comprises a base film 2 and a normal thermal transfer ink layer of three colors, cyan (C), magenta (M), and yellow (Y), which are sequentially provided on one surface of the substrate film 2 . Thermal transfer ink layers of functional ink A (P1) and functional ink B (P2) are provided. Here, the functional ink A contains a bright pigment A such that when the functional thermal transfer ink layer A is formed, the haze value is 1 or more and less than 3, and the functional ink B is when the functional thermal transfer ink layer B is formed. A luster pigment B having a haze value of 3 or more and less than 6 is included. Further, the functional thermal transfer ink layer A and the functional thermal transfer ink layer B exhibit the same interference color. In this manner, all the thermal transfer ink layers are provided on the same base film, and a single ink ribbon can be provided, which is easy to handle and does not complicate the construction of the printer.

If necessary, a black (Bk) ink layer may be provided, and a peeling layer may be provided between the substrate film and the thermal transfer ink layer on the other surface of the substrate film, that is, the surface in contact with the thermal head. You may provide a coat layer, respectively. Further, when using the indirect thermal transfer method, an adhesive layer may be further provided for adhering to the information recording medium at the time of retransfer. Further, it is known to provide a sensor mark for detecting the position of each ink layer, and it can be used as appropriate.

As the bright pigment A used in the functional thermal transfer ink layer A, for example, synthetic mica (synthetic glass) coated with titanium oxide (TiO ₂ ) to a thickness of 0.5 μm or more and 3 μm or less can be used. The haze value of the thermal transfer ink layer A is 1% or more and less than 3%. As the bright pigment B used in the functional thermal transfer ink layer B, natural mica coated with titanium oxide to a thickness of 0.5 μm or more and 3 μm or less can be used, and the haze value of the functional thermal transfer ink layer B is 3% or more. %. In either case, the titanium oxide can be further coated with iron oxide (FeO, Fe ₂ O ₃ ) or the like. For this reason, the base color of the portion to which the functional thermal transfer ink layer B has been transferred appears to be less transparent than the base color of the portion to which the functional thermal transfer ink layer A has been transferred, resulting in a difference in appearance. .

Various known pigments can be used as the pigments used in the cyan (C), magenta (M), and yellow (Y) ink layers. Specific examples include azo dyes such as phthalimide yellow, benzimidazolone orange, sulfonamide yellow, and benzimidazolone yellow, phthalocyanine pigments, diketopyrrolopyrrole, quinophthalone, isoindolinone, and diaminodianthraquinone. It is not limited to these.

As the base film 2, plastic sheets such as polyethylene terephthalate (PET), polypropylene (PP), polycarbonate (PC), polymethyl methacrylate (PMMA), polyethylene (PE), etc. are preferably used. The thickness of the base film 2 is generally about 1 to 100 μm, but a thinner thickness is preferable in order to improve transferability, and a thickness of about 1 to 10 μm is particularly preferable.

In the case of the thermal transfer recording system, there are a direct transfer recording system in which an image is directly transferred to an information recording medium and an indirect transfer recording system in which an image once transferred and recorded on an intermediate transfer medium is transferred again to an information recording medium. can be applied to either of them. FIG. 2 shows an example of using the thermal transfer medium 1 in an indirect thermal transfer printer.

The printer 100 includes a primary transfer section composed of a thermal head 101 and a platen roller 102 as main members, and a secondary transfer section composed of a heat roller 107 and a conveying roller 108 as main members. In the primary transfer portion, the thermal transfer medium 1 and the intermediate transfer medium 201 unwound from the unwind rolls 103 and 105 respectively pass between the thermal head 101 and the platen roller 102 , and the thermal transfer medium 1 is transferred to the take-up roll 104 . , and the intermediate transfer medium 201 is conveyed to the secondary transfer portion.

As the intermediate transfer medium, a resin film such as polyethylene terephthalate can be used, and a release layer and an image-receiving layer can be formed in this order and used as a laminate. Examples of materials for the image receiving layer include thermoplastic resins such as propylene resin, polyethylene terephthalate resin, polyacetal resin and polyester resin.

At the time of primary transfer, the thermal head 101 and the platen roller 102 are brought into pressure contact, and thermal transfer recording of each color is performed on the intermediate transfer medium 201 from the thermally transferable ink layer of each color of the thermal transfer medium 1 in accordance with the image information. . The intermediate transfer medium 201 is reciprocally moved by the number of colors to be recorded (five colors in this example), and the colors are superimposed on a predetermined portion. The order of color superimposition is not particularly limited, but in the case of the thermal transfer medium 1 in FIG. P2), and so on.

After the primary transfer is completed, the intermediate transfer medium 201 on which the predetermined image recording has been performed is conveyed to the secondary transfer portion. The intermediate transfer medium 201 is sandwiched between the heat roller 107 and the transport roller 108 and transported together with the recording medium 109 as an information recording medium transported by a transport mechanism (not shown) while being pressed against each other. The image is thermally and pressure-transferred onto the recording medium 109, completing the secondary transfer. After completing the secondary transfer, the intermediate transfer medium 201 is taken up by the take-up roll 106 or rewound by a predetermined amount for primary transfer of the next image.

An information recording medium according to the present invention, in which the thermal transfer medium 1 is used and a pattern such as a character or an image is formed as a display image with a functional ink containing a luster pigment, will be described. FIG. 3 shows an example of a cell pattern A11 formed by thermally transferring the functional ink A from the thermal transfer medium 1 and a cell pattern B12 formed by thermally transferring the functional ink B. FIG. The cell pattern A11 and the cell pattern B12 are composed of one or a plurality of dots thermally transferred by a thermal head, which is a recording head.

As described above, the functional ink A contains the glitter pigment A, the functional thermal transfer ink layer A has a haze value of 1% or more and less than 3%, the functional ink B contains the glitter pigment B, and has a functional The thermal transfer ink layer B has a haze value of 3% or more and less than 6%, and exhibits the same interference color. FIG. 3 is a diagram viewed from an angle at which the interference color disappears, and different haze values result in different appearances. The cell pattern A11 formed by thermally transferring the functional ink A from the functional thermal transfer ink layer A having a small haze value appears to have higher transparency, and the functional ink B is thermally transferred from the functional thermal transfer ink layer B having a large haze value. The cell pattern B12 thus formed is inferior in transparency and looks more cloudy.

FIG. 4 shows an example of forming a cell matrix by appropriately arranging the cell pattern A and the cell pattern B in combination. Similarly, it can be formed by thermal transfer from the thermal transfer medium 1 . FIG. 4A shows the cell matrix 10 viewed from an angle where the cell pattern A11 and the cell pattern B12 lose interference color. As shown in FIG. 3, the cell pattern A11 and the cell pattern B12 have different appearances due to the different haze values, so the pattern (OK characters) of the cell pattern B12 appears to stand out as a display image here. there is

FIG. 4B shows the cell matrix 10 viewed from an angle at which the cell pattern A11 and the cell pattern B12 exhibit interference colors. Since both cell patterns exhibit the same interference color, the cell patterns A and B are substantially uniform and appear on the surface 13 of the same color (for example, green), and no specific pattern appears on the cell matrix 10 .

FIG. 5 shows an example of an image pattern actually provided on an information recording medium such as a card. In the image pattern 20, a cell matrix is formed in the central portion by combining cell patterns A11 and B12 similar to the cell matrix 10, and a normal image 21 surrounds the periphery. The method of forming the normal image 21 is not particularly limited, and may be normal printing, optical elements such as holograms, normal pearl printing, or the like. It may be formed by transferring normal thermal transfer ink of three colors of yellow (Y).

FIG. 5(a) shows the image pattern 20 viewed from an angle where the cell pattern A11 and the cell pattern B12 do not exhibit an interference color. The characters appear to stand out as the displayed image.

FIG. 5(b) shows the image pattern 20 viewed from an angle where the cell pattern A11 and the cell pattern B12 exhibit interference colors. (e.g. green) surface 13 and the image pattern 20 does not show a particular display image.

FIG. 6 shows an example in which an image pattern equivalent to the image pattern 20 is provided on the surface of the information recording medium using the thermal transfer medium 1 as an image forming portion. The information recording medium 30 is a card-like medium, on the surface of which is formed a second image forming portion 32 consisting of ordinary characters and a face photograph, and on another portion a first image forming portion equivalent to the image pattern 20. 31 are formed. As described above, the first image forming unit 31 is operated when a predetermined display image appears to stand out depending on the viewing angle (FIG. 6(a)) and when a substantially uniform interference color is visible (FIG. 6(b)). becomes a mode in which it appears to switch. The second image forming unit 32 may be formed by a method such as normal printing, but the normal thermal transfer ink of three colors of cyan (C), magenta (M), and yellow (Y) of the thermal transfer medium 1 may be used. can also be formed by transferring.

FIG. 7 shows a cross section of the information recording medium 30 of FIG. 6(a) at the position of straight line XX'. The information recording medium 30 has a second image forming section 32 and a first image forming section 31 formed on a substrate 35 with an adhesive layer 34 interposed therebetween. In the first image forming section 31, the cell pattern A11 and the cell pattern B12 are appropriately arranged so that a predetermined display image can be displayed. Also, an overlay 33 is formed as a protective layer. Here, the information recording medium 30 is an example recorded by the indirect thermal transfer recording system, and the overlay 33 is obtained by transferring the image receiving layer of the intermediate transfer medium.

In the second image forming unit 32, dots 36 are formed by transferring normal thermal transfer inks of three colors of cyan (C), magenta (M), and yellow (Y) of the thermal transfer medium 1. It is

The material of the base material 35 is not particularly limited, but for example paper such as natural paper and synthetic paper, polyethylene terephthalate resin (PET), polyvinyl chloride resin (PVC), thermosetting polyester resin, polycarbonate resin, Synthetic resins such as polymethacrylic resin and polystyrene resin, ceramics such as glass, earthenware and porcelain, or metallic materials such as simple metals and alloys may be used.

As a result, the information recording medium 30 has a characteristic display image in which the pearl luster, which is the interference color of the luster pigment, and the display image in the pattern that emerges due to the difference in appearance due to the difference in the haze value, are switched depending on the viewing angle. Since it has a display effect, it is possible to obtain a recording medium with enhanced anti-counterfeiting and anti-counterfeiting effects and improved security. Moreover, the image forming section having such a unique effect can be formed by thermal transfer recording from one thermal transfer medium, and can be efficiently formed. In addition, different information can be recorded on each information recording medium, so that a forgery prevention medium having a higher forgery prevention effect can be obtained.

FIG. 8 shows a second embodiment of the cell pattern formed by thermally transferring the functional ink from the thermal transfer medium 1. A core dot α411 formed with the functional ink A and adjacent to the core dot α411 are shown in FIG. , a cell pattern C41 composed of a peripheral dot β412 formed with functional ink B, a core dot β421 formed with functional ink B, and a core dot β421 adjacent to the core dot β421. A cell pattern D42 consisting of a peripheral dot β422 formed with functional ink A and having the same area as the dot β421 is shown. Here, the aspect seen from the angle at which the interference color disappears is shown, but when viewed from the angle exhibiting the interference color, the core dots and the peripheral dots exhibit the same interference color (for example, green). Therefore, both the cell pattern C41 and the cell pattern D42 appear to have a substantially uniform color.

FIG. 9 shows an example of a cell matrix in which the cell patterns C41 and D42 are combined and arranged at equal pitches to form characters, numerals, symbols, and the like. In the cell matrix 50 of FIG. 9, the character pattern "123" is formed by the cell pattern D42 with the cell pattern C41 as the "ground". In addition, here, the aspect seen from the angle at which the interference color disappears is shown.

Although the cell matrix 50 is shown large in FIG. 9 for ease of understanding, if the areas of cell pattern C and cell pattern D are sufficiently small, the difference in appearance due to the difference in haze value is discernible under normal visual observation. and it is difficult to distinguish between core dots and margin dots. Further, since the core dot α411 and the peripheral dot β412 and the core dot β421 and the peripheral dot β422 have the same area, the cell pattern C and the cell pattern D cannot be distinguished from each other. As a result, the character pattern "123" becomes a latent image when viewed with normal eyes, and the portion of the cell matrix 50 appears to have a substantially uniform color. Here, "sufficiently small area" means that the length of one side is 0.25 to 1 mm or less.

In order to make the cell matrix 50 of FIG. 9 visible, a fly-eye convex lens array 60 as shown in FIG. 10 is used. As can be seen from the sectional view taken along the straight line YY' shown in FIG. 10B, the convex lens array 60 is formed by two-dimensionally arraying convex lenses 61 on a transparent substrate portion 62 at equal pitches. It is the same as the pitch of the cell matrix 50 . When this convex lens array 60 is superimposed on an image pattern 70 in which a cell matrix 50 is formed in the central portion of the same image pattern as the image pattern 20 exemplified in the previous embodiment, the portion of the cell pattern D42 is as shown in FIG. The core dots β formed with the functional ink B can be seen, and the core dots α formed with the functional ink A can be seen in the portion of the cell pattern C, which is a latent image with normal visual observation. The character pattern "123" can be visually recognized.

This is the case where the focus of the convex lens 61 is aligned with the core dot α411 formed with the functional ink A and the core dot β421 formed with the functional ink B, as schematically shown in FIG. Only the portion of the core dot α411 and the core dot β421 is magnified by the convex lens 61, and the portions of the peripheral dot α412 and the peripheral dot β422 become difficult to see. The latent image character pattern ("123" in this case) becomes visible.

At this time, if the shape of the core dots is easily magnified, for example, squares such as the core dots α411 and β421 shown in FIG. Note that the shape of the core dot may be any shape other than square as long as it is easy to focus, and may be circular, elliptical, or polygonal other than square, for example.

FIG. 13 shows an example in which an image pattern equivalent to the image pattern 70 is provided on the surface of the information recording medium using the thermal transfer medium 1 as an image forming portion. The information recording medium 80 is a card-like medium, on the surface of which is formed a second image forming portion 82 consisting of ordinary characters and a face photograph, and on another portion a first image forming portion equivalent to the image pattern 70. 81 is formed. The first image forming unit 81 usually does not show patterns as shown in FIG. 13(a), but by superimposing the convex lens array 60 as shown in FIG. 123”) appears to stand out. The second image forming unit 82 may be formed by a method such as normal printing, but the normal thermal transfer ink of three colors of cyan (C), magenta (M), and yellow (Y) of the thermal transfer medium 1 may be used. can also be formed by transferring.

FIG. 14 shows a cross section of the information recording medium 80 of FIG. 13(b) taken along line ZZ'. The information recording medium 80 has a second image forming portion 82 and a first image forming portion 81 formed on a substrate 85 with an adhesive layer 84 interposed therebetween. In the first image forming section 81, the cell pattern C41 and the cell pattern D42 are appropriately arranged so that a predetermined display image can be displayed. Also, an overlay 83 is formed as a protective layer. Here, the information recording medium 80 is an example recorded by the indirect thermal transfer recording system, and the overlay 83 is obtained by transferring the image receiving layer of the intermediate transfer medium.

As a result, when the information recording medium 80 is viewed with the naked eye, no particular image or character is visible in the first image forming section 81 . It has a characteristic display effect that a display image formed by a difference in appearance due to a difference in haze value appears, and a recording medium with enhanced anti-counterfeiting and anti-counterfeiting effects and improved security can be obtained. . Moreover, the image forming section having such a unique effect can be formed by thermal transfer recording from one thermal transfer medium 1, and can be formed efficiently. In addition, different information can be recorded on each information recording medium, and a forgery prevention medium having a higher forgery prevention effect can be obtained.

As described above, according to the thermal transfer medium and the information recording medium of the present invention, a displayed image has a unique visual effect of a difference in appearance due to a difference in the haze value of the functional thermal transfer ink layer containing the luster pigment. can be formed as a latent image pattern in a fine cell pattern, which not only makes counterfeiting difficult, but also makes the latent image pattern invisible under normal conditions, making it easy to see that the latent image pattern is provided. It is possible to adopt an aspect in which the information is not known, and the opportunity to induce forgery or falsification can be reduced, and a high anti-counterfeiting effect can be obtained.

The present invention will be specifically described below with reference to specific examples.
<Example 1>
・On the substrate film, functional ink A using a bright pigment made of synthetic mica coated with titanium oxide (TiO ₂ ) and functional ink B using a bright pigment made of natural mica coated with titanium oxide were applied. Using the processed thermal transfer medium, a 1 mm square cell pattern A and a cell pattern B were combined on a PVC card by an indirect thermal transfer printer to form an image pattern in the form of "OK" characters.
- At this time, the film thickness of the titanium oxide coated on the synthetic mica and the natural mica was the same.
The haze value of the functional thermal transfer ink layer A was 2%, and the haze value of the functional thermal transfer ink layer B was 4%.
・When the PVC card was viewed from the normal direction, the characters "OK" were visible due to the difference in the haze value.
- When the PVC card was tilted so that the interference color was visible, the cell pattern A and the cell pattern B exhibited the same interference color, and the image pattern was no longer visible.
As described above, an image pattern that can be recorded on demand as individual information by thermal transfer recording can be provided so as to be switchable between a latent image and a visible image.

<Comparative Example 1>
- Two types of transparent inks were applied to the areas where the functional inks were transferred in Example 1. A filler was added to one side of the transparent ink so that the haze value was different, and the haze value was set to 5.
- In the same manner as in Example 1, an image pattern of "OK" was formed on a PVC card.
・When the PVC card was viewed from the normal direction, the characters "OK" were visible due to the difference in the haze value.
• Even if the PVC card was tilted, the interference color could not be seen because it was not a bright pigment, and a latent image could not be formed.

<Example 2>
Using the same thermal transfer medium as in Example 1, a 1 mm square cell pattern C and a cell pattern D are combined on a PVC card by an indirect thermal transfer printer, and an image pattern is formed in the form of "OK" characters. formed.
- The image pattern was not visible when the PVC card was viewed from the normal direction.
・When the PVC card was tilted to make the interference color visible, the interference color was seen almost uniformly.
・When convex lens arrays with a pitch of 1 mm were superimposed, a difference in appearance occurred due to a difference in haze value, and the characters "OK" were visible.

<Comparative Example 2>
- A piece was prepared by applying one kind of general-purpose pearl ink to the part where the functional ink was transferred in Example 1.
・When viewed from an angle exhibiting interference color, a substantially uniform interference color was seen.
- Even if the same convex lens array as in Example 2 was superimposed, no image pattern appeared.

Reference Signs List 1 Thermal transfer medium 2 Base film 10 Cell matrix 11 Cell pattern A
12 Cell pattern B
13 Same-color surfaces 20, 70 Image pattern 21 Normal images 30, 80 Information recording bodies 31, 81 First image forming units 32, 82 Second 2 image forming portions 33, 83 overlays 34, 84 adhesive layers 35, 85 base material 36 dots 41 cell pattern C
411 ... Nuclear dot α
412 Peripheral dot β
42 Cell pattern D
421 ... Nuclear dot β
422 Peripheral edge dot α
50 Cell matrix 60 Convex lens array 61 Convex lens 62 Transparent substrate unit 100 Printer

Claims (7)

One or more thermal transfer ink layers containing pigments and at least two functional thermal transfer ink layers made of functional inks containing luster pigments are provided in a frame-sequential manner on one side of the support,
The functional thermal transfer ink layer has a functional thermal transfer ink layer A made of a functional ink A containing a bright pigment A and a functional thermal transfer ink layer B made of a functional ink B containing a bright pigment B. death,
The functional thermal transfer ink layer A and the functional thermal transfer ink layer B have the same interference color,
A thermal transfer medium, wherein the functional thermal transfer ink layer A and the functional thermal transfer ink layer B have different haze values. 2. The method according to claim 1, wherein the functional thermal transfer ink layer A has a haze value of 1% or more and less than 3%, and the functional thermal transfer ink layer B has a haze value of 3% or more and less than 6%. Thermal transfer media. on the substrate,
one or more thermal transfer ink layers containing pigments;
At least a functional thermal transfer ink layer A made of a functional ink A containing a bright pigment A and a functional thermal transfer ink layer B made of a functional ink B containing a bright pigment B are thermally transferred,
The functional thermal transfer ink layer A and the functional thermal transfer ink layer B have the same interference color, the functional thermal transfer ink layer A and the functional thermal transfer ink layer B have different haze values, and an overlay layer is an information recording medium laminated with
At least one image forming unit in which a predetermined display image is formed using the functional ink A and the functional ink B is provided, and the image forming unit has the functionality when viewed from a predetermined viewing angle. An information recording medium characterized in that the same interference color exhibited by the thermal transfer ink layer A and the functional thermal transfer ink layer B can be seen, and the interference color disappears when the observation angle is changed. 4. The method according to claim 3, wherein the functional thermal transfer ink layer A has a haze value of 1% or more and less than 3%, and the functional thermal transfer ink layer B has a haze value of 3% or more and less than 6%. information record. The image forming unit forms a predetermined display image using at least two types of cell patterns, a cell pattern A formed with the functional ink A and a cell pattern B formed with the functional ink B. 5. The information recording medium according to claim 3 or 4, characterized by: A cell pattern C formed by a core dot α formed with a functional ink A and a peripheral dot β formed with a functional ink B adjacent to the core dot α and having the same area as the core dot α. ,
A cell pattern D formed of a core dot β formed with a functional ink B and a peripheral dot α formed with a functional ink A adjacent to the core dot β and having the same area as the core dot β. 5. The information recording medium according to claim 3, wherein a predetermined display image is formed using at least two kinds of cell patterns of . By superimposing a convex lens array having the same pitch as the pitch at which the cell patterns are arranged on the information recording medium according to claim 6, the functional ink of the core dots α of the cell pattern C and the core dots β of the cell pattern D A method of displaying a cell pattern, characterized in that only the base color of the cell pattern is displayed.

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